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The role of laparoscopy in the treatment of endometriosis
m
Modern trends Edward E. Wallach} M.D., FERTILITY AND STERILITY
Asei(l~i.ate ~.
Printed on acid-free paper in U.S.A.
Copyright" 1991 The American Fertility Society
The role of laparoscopy in the treatment of endometriosis
AndrewS. Cook, M.D. John A. Rock, M.D.* The Johns Hopkins Hospital, Department of Gynecology and Obstetrics, Division of Reproductive Endocrinology, Baltimore, Maryland
The primary goal in the surgical treatment of endometriosis is complete removal of both typical and atypical endometrial implants. 1 The typical "powder burn" lesion has been traditionally taught as being the standard appearance of an endometriotic lesion. Although the pigmented implant is the most easily identified type of lesion, it is becoming apparent that these implants contain inactive glands and stoma embedded with hemosiderin. In contrast, the atypical or nonpigmented lesion contains active endometriotic glands and stroma that may result in progression of disease and symptomatology. The depth of the implant is also related to disease activity, with deep endometriosis containing very active disease. 2 It is believed, but not proven, that excision or ablation of the endometrial implants will increase the fertility potential of the patient. 3 The advent of operative laparoscopy represents an advancement in the treatment of endometriosis.4-10 The advantages of laparoscopic treatment include a decrease in patient morbidity, reduction in length of hospital stay and costs, as well as the opportunity to treat at the time of diagnosis, and potentially a reduction in postoperative adhesion formation with an increased pregnancy rate (PR). 11 Minimal postoperative adhesion formation is noted clinically with laparoscopic surgeryP- 14 The results of controlled animal studies have varied with some but not all studies demonstrating a significantly lower postoperative adhesion formation after operative laparoscopy in comparison with laparotomy.15·16 It has been demonstrated at second-look laparoscopy that 58% of patients without previous adhesions will experience adhesion formation, and 92% of patients who had adhesions lysed at laparotomy will have persistent or reformation of adhesions.17 Surgical treatment of endometriosis falls into two basic categories: (1) ablation and/or resection of enVol. 55, No.4, April1991
dometriotic implants in cases with normal pelvic anatomy and (2) ablation and/or resection of endometriotic implants and correction of abnormal pelvic anatomy. Resection or ablation of endometrial implants is best accomplished surgically through the laparoscope rather than through the open abdomen. Debate arises, however, over potential differences in PRs depending on which endoscopic method is used to ablate (electrocautery, endocoagulation, or laser) or resect the endometrial implants. The extent of anatomical distortion that can or should be treated through the laparoscope rather than at laparotomy is the subject of considerable controversy. Some surgeons feel that certain limitations encountered with laparoscopic surgery prevent the use of proper surgical technique and therefore acceptable results. There are several technical limitations unique to laparoscopic surgery. These include loss of depth perception, inability to directly palpate the tissue, limitation of the instrumentation including the number and orientation of the instruments, and the increased distance between the surgeon's hand and the operating field. The remote position of the operator's hands and lack of hand support can make some fine and exact movements difficult. The extent of endometriosis that can be treated laparoscopically is related to the restricted access of the surgical field. Many of the limitations encountered during laparoscopic surgery can be overcome by the skill of the surgeon; however, certain difficult microsurgical dissections cannot be adequately performed laparoscopically. In comparison with laparoscopy, laparotomy will provide (1) better identification of tissue planes through enhanced depth perception and direct palpation of tissue and (2) improved access to the tissue with greater precision of movements, increased flexibility in orientation of instrumentation, and a superior variety of available instrumenCook and Rock
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663
tation. Therefore the decision to perform the procedure through the laparoscope or through the open abdomen is not dependent on the stage of endometriosis encountered as determined by The American Fertility Society (AFS) classification system. Rather, the failure to perform the procedure endoscopically results from (1) the inability to safely dissect between tissue planes and (2) the need for improved access to the tissue for atraumatic manipulation and strict adherence to the principles of good surgical technique. Specific procedures involved in the treatment of endometriosis that can be treated laparoscopically include ablation of peritoneal endometriosis, adhesiolysis, ovarian cystectomy, oophorectomy, and salpingectomy. Procedures for the treatment of endometriosis that require laparotomy include bowel resection, complete presacral neurectomy, and excision or ablation of deep endometriosis that cannot safely be isolated from vital structures. Some large endometriomas will need to be treated at laparotomy and a wide range of opinion exists regarding the role of laparoscopic tubal reconstruction. The ultimate choice of modality must depend on the proven effectiveness of therapy. DIAGNOSIS OF ENDOMETRIOSIS
Awareness of the wide range of visual appearance of endometriosis is necessary to make an accurate diagnosis so that proper treatment can be instituted and the surgeon may avoid incorrectly labeling a patient as having unexplained infertility or pain. It has been estimated that the diagnosis of endometriosis has been missed in 7% of patients, and the extent of the disease has been underestimated in as many as 50% of patients. 1 Conversely, it has been shown that many other lesions have an appearance similar to the typical endometrial lesion. These lesions include old suture, ovarian cancer, residual carbon deposits from previous surgery, and hemangiomas. 18,i9 The diagnosis of endometriosis has traditionally been made by visual inspection with identification of the bluish or typical powder burn lesion. It has become evident, over the last several years, that the appearance of endometriosis can be quite varied in its presentation. Several recent articles have described atypical and nonpigmented forms of endometriosis. 1,2,19 Martin et al. l have described as many as 20 different morphological appearances of endometriosis including scarred lesions, red lesions, vesicular lesions, peritoneal windows, yellow-brown patches, and adhesions. The loss of depth perception 664
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Laparoscopic treatment of endometriosis
with the uniocular laparoscope makes diagnosis of some nonpigmented lesions difficult. Redwine 20 has even suggested painting the peritoneum with blood to enhance the diagnosis of subtle lesions. The atypical endometrial lesions may represent early active endometriosis that with time will progress to pigmented lesions. 19 Several studies have shown a 40% to 45% association of endometriosis with peritoneal defects or pockets. 21 ,22 An interesting study by Cornillie et a1. 2 demonstrates a correlation between the activity and the depth of the endometrial implant. Cellular activity was noted in 58% of the superficial implants «1 mm) and 68% of deep implants (?c5 mm). Yet only 25% of intermediate implants (2 to 4 mm) were noted to have cellular activity. The authors postulate that superficial implants represent the initial stage of proliferation of retrograde menstruation. As proliferation of the lesion progresses to an intermediate depth, many of the implants burn out under the influence of the high progesterone in the peritoneal fluid. Implants that survive and invade deeply (>5 mm) are primarily under the influence of circulating steroids and become very active. The assessment of the depth of the lesion at laparoscopy correlated well with the histologic measurements. Magnification with "near-contact laparoscopy" has been proposed to increase the sensitivity of visual diagnosis of endometriosis. 23 Increased magnification may allow identification of subtle peritoneal surface irregularities and excisional biopsy. Magnification up to 8X, depending on the working distance, can be obtained with the laparoscope (Table 1). Several studies using scanning electron microscopy, however, have documented endometriosis in normal appearing peritoneum. 25 - 28 A recent study demonstrated endometriosis (313 JLm ± 185 JLm) by light microscopy present in normal appearing
Table 1 Magnification Rates Obtained With Operating Laparoscopes· Magnification rate Operating laparoscope working distance
Wolf
Olympus
mm
3 5 10
3.19
15 20
1.71
30 50
1.7 1.2
0.73
0.7
8.2 5.7 3.2 2.2
• From Murphy et a1. 2' (Reproduced with permission of the publisher, The American Fertility Society).
Fertility and Sterility
endometrium in 13% of patients with endometriosis and 6% of infertility patients undergoing laparoscopy without endometriosis. 29 Recurrence rates of 13.5% and 40% at 3 and 5 years, respectively, have been documented after surgical treatment. 30 This recurrence of symptoms may represent persistence of microscopic «200 JLm) or retroperitoneal disease. Surgical treatment of endometriosis is therefore most likely cytoreductive rather than ablative. Identification of deep ovarian endometriomas is important for correct staging. A recent study demonstrated the presence of small deep ovarian endometriomas in 48% of patients who had slightly enlarged ovaries (maximum diameter 3.5 to 5 cm) but were otherwise normal in their appearance. 31 Using the Revised American Fertility Society classification system32 (R-AFS), 32% of the patients in this study had stage I endometriosis, 36% stage II endometriosis, none with stage III or IV, and 32% of the patients had no endometriosis. The diagnosis and determination of the diameter of occult ovarian endometriomas was accomplished with ovarian puncture using a 16-gauge needle. After restaging, 8% of patients had stage I endometriosis, 16% stage II endometriosis, 64% stage III endometriosis, and 12% stage IV endometriosis. The authors found preoperative sonographic evaluation to be useful in screening for small ovarian endometriomas.
TREATMENT OF ENDOMETRIOTIC IMPLANTS
Several basic techniques are used in the surgical ablation of endometriosis. Endometrial implants can be resected, coagulated, or vaporized. IS Coagulation can be achieved by using the unipolar or bipolar electrocautery, the endocoagulator, or the various surgical lasers. A complete working knowledge ofthe biophysical principles of the various modalities (electrocautery, endocoagulation, surgical lasers) is necessary before their clinical use. Many patients are under the impression that the surgical laser offers a new and improved form of treatment with a marked increase in the success rate over other modalities, and some members of the medical profession have contributed to this impression. Much of this misperception is based on the lack of understanding of the basic physical principles of various available modalities, including surgical lasers and the laser-tissue interaction. An understanding of these principles will allow the surgeon to both realize the limitations and utilize the advantages of a given treatment modality. Vol. 55, No.4, Aprii1991
All of the above mentioned treatment modalities work through the generation of thermal energy. Blood vessels and lymphatic ducts act as convective systems to dissipate excessive heat. When energy accumulates faster in the tissue than it can be dissipated by these systems, the temperature of the tissue will rise. Coagulation occurs at temperatures < 100°C, whereas vaporization and cutting occur at temperatures> 100°C. Coagulation results in denaturation of macromolecules, primarily proteins, with breakage of the bonds that stabilize the conformation of the molecule. Denaturation of enzymes occurs in the range of 40°C to 65°C and denaturation of deoxyribonucleic acid occurs above 80°C. Conversion of intracellular and extracellular water to vapor, with a 1,670-fold increase in volume, occurs at temperatures> 100°C. The rapid expansion of vapor results in transformation of thermal energy to mechanical energy. The mechanical energy performs work on the remaining solid tissue, tearing the cellular membranes and displacing cellular components, causing tissue separation. Biophysical Principles of Electrocautery
The standard household current is an alternating current with a frequency of 60 cycles/so Muscles and nerves respond to frequencies below 10,000 Hz. Electrocautery generators increase the frequency of the electrical current from 60 Hz to frequencies between 300,000 and 4 million Hz. The first surgical electrocautery generator was designed by William Bovie and is the basis for the term Bovie cautery.33 Electrocautery generators have two basic modes, cutting and coagulation. The cutting current is a continuous current, whereas the coagulating current is a current that is interrupted with periods of electrical inactivity (Fig. 1). The cutting current results in a rapid increase in temperature with vaporization, whereas the coagulating current allows for a less intense rise in the temperature, resulting in coagulation. Electrocauterization requires a closed circuit to work. Unipolar cautery incorporates the patient's entire body into the circuit. High-frequency electrical current flows from the generator through the laparoscopic electroinstrument, through the patient, and then exits through the grounding pad and returns to the generator. The potential disadvantages of unipolar cautery are related to (1) the unpredictable route of the electrical current and its potential thermal damage and necrosis to vital structures (e.g., bowel) and (2) the relatively large area of thermal damage and necrosis that is not visible at the time of surgery. Peritoneal damage may result in inCook and Rock
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A
element at the tip of the Teflon-coated probe generating temperatures of up to 120°C. The major suggested advantages of endocoagulation are (1) limitation of the area of necrosis and (2) elimination of the high-frequency electrical current in the abdominal cavity, thus eliminating the potential for electrical burns. Studies have shown that coagulation only occurs to a depth of 1 to 2 mm and thus is not effective in ablation of deep endometrial implants. 36 The primary role of endocoagulation is ablation of superficial endometrial implants and coagulation of intact vessels or minor oozing. The endocoagulator does not work well in obtaining hemostasis of actively bleeding vessels, which dissipate the heat generated by this relatively low energy source.
B
Biophysical Principles of Lasers Figure 1 Electrocoagulation currents. (A), "Cutting current." (B), "Coagulating current."
creased adhesion formation, and unrecognized bowel injuries have resulted in death. 34 The risk of the above complications occurring is related to several factors. The newer generators are much safer than the original spark gap generators, and the skill of the surgeon is paramount in the safe use of intraperitoneal electrocautery. The extent of tissue penetration is related to the duration of application, power and type of current, and the size of the electrode. Thus, the application of monopolar fine needle electrocautery of short duration with blended current may be safely used in adhesiolysis with minimal damage to surrounding tissue. Endoscopic use of the bipolar electrocautery is usually safer than unipolar cautery. High-frequency current from the generator passes from one paddle of the bipolar instrument, through the intervening tissue, to the other paddle and back up the laparoscope to the generator, completing the circuit. As a result, essentially, the only tissue exposed to electrical current, and thus cauterization, is that between the paddles of the bipolar instrument. The area of tissue necrosis is more controlled and limited than that seen with unipolar cautery, provided lateral thermal spread is limited by electrical current applications of short duration. Biophysical Principles of Endocoagulation
Endocoagulation, developed by Semm, utilizes direct application of heat to the tissue for coagulation. 35 Electrical current passes through a resistance 666
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The laser (an acronym for light amplification by stimulated emission of radiation) is a useful instrument in the armamentarium of surgical tools. Four basic phenomena may occur in tissue when it is struck by laser light. These include (1) absorption by the tissue; (2) scattering within the tissue; (3) reflection from the surface, which results in decreased efficiency of the laser; and (4) transmission through the tissue. The power of the laser beam is attenuated as a result of both absorption (primarily by cellular water) and scattering as it moves through the depth of the tissue. The absorption oflaser light in a given tissue results in an increase in the kinetic and vibrational energy within the atoms and the molecules, which is manifested as thermal energy. Thermal energy is the means by which the surgical laser performs all of its functions. Scattering of the laser beam results in a change in direction of a portion of the laser light without an overall loss of energy. There is a decrease in the power of the initial direction of the laser beam and a measurable power density in directions not parallel with the axis of the laser beam. Scattering of the laser light results in a lateral spread ofthe thermal effect on the tissue. The wavelength of a laser determines the absorption to scattering ratio, which is primarily responsible for the individual characteristic of the various surgicallasers (Table 2). Lasers with a long wavelength (>3,000 nm) have a low scatter to absorption ratio and are thus effective for tissue vaporization but poor for coagulation. Lasers with a short wavelength (700 to 1,400 nm) have good coagulation abilities but are poor vaporizers. The scatter to absorption ratio of visible lasers (e.g., potassium-titanyl-phosphate [KTP] and argon lasers) is highly dependent on the color of the target Fertility and Sterility
Table 2
Biophysical Properties of the Different Lasers a Maximum power output
Wavelength
Laser
CO 2 Argon
Extinction length b
Fiber compatible
Primary effect
Secondary effect
~m
w
mm
10.6 0.488 to 0.514
500 20
0.05 0.2
No Yes
Vaporization Coagulation
1.06
100
0.8-2.0
Yes
Coagulation (vaporization at high power)
Nd:YAG
None Delayed thermal damage Significant backscatter
a From Vancaillie and Schenken. 37 (Reproduced with permission of the publisher).
b Extinction length is the depth of tissue that absorbs 90% of energy at standardized power and exposure time. An index of the laser's ability to penetrate tissue.
tissue. These lasers have fairly good coagulating ability but are poor vaporizers. The ideal laser would have a variable wavelength that could be changed and thus the degree of coagulation or vaporization selected. The parameters of the laser that effect the energy delivered to the tissue include power, duration, and the wavelength of the electromagnetic radiation. The power of the laser beam, which is proportional to the number of photons per second, is known as watts. The power density, which is the number of watts per cm 2 , is more reflective of the energy delivered to a unit area. For any given power (watt), the power density is directly proportional to the spot size (Table 3). Thus, the amount of energy to which a given tissue is exposed is dependent on both the power setting of the laser and the spot size of the beam. Duration of exposure affects both the depth of penetration and the relative degree of vaporization or coagulation necrosis. The wavelength of the electromagnetic radiation emitted by a laser is unique to the active medium ofthe laser (e.g., carbon dioxide [C0 2 ] or argon).
but poor for the purpose of coagulation. As demonstrated in Figure 2, the power density of the laser beam is in a Gaussian distribution with a higher power density in the middle portion of the beam and decreasing levels toward the periphery.39 The zone of thermal necrosis with CO 2 laser is minimal initially and is further minimized by the progressive elongation of the bore contour secondary to the relative increased central bore speed (Fig. 2). The zone of thermal necrosis in the superpulse mode is approximately one third of the zone of thermal necrosis in the continuous setting. This setting is therefore used in situations in which maximal tissue vaporization (cutting or ablation) and minimal tissue necrosis or coagulation is desired. The clinical relevance of the contour of the bore hole created by the CO 2 laser is demonstrated by its excellent vaporization and poor coagulation ability. As a CO 2 bore hole reaches and begins to penetrate the wall of a blood vessel, vaporization creates a small hole yet only minimal coagulation occurs. With the creation of a hole in the wall of a blood vessel, there is release of plasma. The plasma then acts to dissipate the heat and prevents further vaporization as well as preventing coagulation of the blood vessel and thus hemostasis.
CO2 Laser
The CO 2 laser has a wavelength of 10,600 nm and thus is excellent for ablation and cutting of tissue Table 3
Power Density Charta Power
Spot size
2
5
10
15
20
25
30
40
50
5,497 1,374 611 220 98 55 35 24
13,743 3,436 1,527 550 244 137 88 61
27,485 6,871 3,054 1,099 489 275 176 122
41,228 10,307 4,581 1,649 733 412 264 183
54,970 13,743 6,108 2,199 977 550 352 244
68,713 17,178 7,635 2,749 1,222 687 440 305
82,455 20,614 9,162 3,298 1,466 825 528 366
109,940 27,485 12,216 4,398 1,954 1,099 704 489
137,425 34,356 15,269 5,497 2,443 1,374 880 611
mm
0.2 0.4 0.6 1.0 1.5 2.0 2.5 3.0
a Power density is W /cm2 • From Fuller TA.38 (Reproduced with permission of the publisher). Vol. 55, No.4, April 1991
Cook and Rock Laparoscopic treatment of endometriosis
667
sure, and automatically adjusts the flow rate, thus maintaining an adequate pneumoperitoneum. Neodymium Yttrium-Aluminum-Garnet (Nd:YAG) Laser
Figure 2 Cross section of CO 2 laser bore hole with elongation of vaporization with time (t). (From Fisher. 3• Reproduced with permission of the publisher).
The primary disadvantages of the CO 2 laser are its poor coagulation potential, its need for use of an articulating arm system, and its relatively high degree of smoke production. The potential for modification of the CO 2 laser to coagulate tissue is limited because of the wavelength characteristic. When in alignment, the articulating arm system works quite well. However, because of the need for a multiple mirror system, maladjustment of anyone of these mirrors or fatigue of any portion of the articulating arm will result in malalignment of the laser beam with movement of the articulating system. The waveguide system minimizes malalignment problems encountered with the articulation system. 40 Fiberoptic delivery systems are currently under development for the CO 2 laser but are not available clinically at this time. Smoke production, along with carbonization, is a result of burning of the solid residues that are expelled upwardly from the laser bore. This results in significant smoke production along with carbonization. There are no data currently available on potential side effects of the carbonization, therefore, the pelvis should be lavaged to remove as much of the residual carbon particles as possible. The smoke can be removed with a smoke evacuator and high-flow delivery systems. The stateof-the-art insufflator delivers CO 2 gas into the peritoneal cavity at a maximum rate of 6 Ljmin, simultaneously monitors the intra-abdominal pres668
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Laparoscopic treatment of endometriosis
The Nd:YAG laser has a wavelength of 1,064 nm, which results in properties of good coagulation and poor vaporization. The high degree of scatter of the Nd:YAG beam within tissue results in lateral dispersement of the thermal effect. In contrast to the CO 2 laser, the diameter of the affected area is much greater than that of the laser beam (Fig. 3). When coagulation of the tissue has occurred, there is a dramatic increase in the scattering coefficient, and the affected volume spreads laterally with minimal increase in the depth of penetration. The degree of lateral dispersement of the thermal energy also is time dependent. The Nd:YAG laser beam is delivered by a quartz optical fiber. The waves of the laser emerge from the tip with a divergence of 5 to 15 degrees, thus there is a marked decrease in the power density as the distance from the target tissue increases. As a result, the tip of the fiber must be placed in close proximity to the tissue to afford effective coagulation and vaporization. In 1984, the sapphire tip was introduced for use with the Nd:YAG laser.39 A variety of contours that had the effect of either focusing or defocusing the laser beam for the desired effect were introduced. 41 •42 A focusing or convergence of the laser beam results
LLr-A..----
QUlrtz Fiber
to-Witt Glussi.n BUJI of Md-YAG lner
Figure 3 Cross section of Nd:YAG laser bore hole with divergence of beam from quartz fiber. (From Fisher.39 Reproduced with permission of the publisher).
Fertility and Sterility
in an increase in cutting and vaporizing ability. In addition, the sapphire tip was designed to be used in contact with the tissue, which not only helped reduce the scattering of the beam but also eliminated the 50% reflection at the surface of the tissue and thus greatly enhanced the efficiency of this laser.43 The primary drawbacks of the sapphire tip are the disposable nature (the tip melts with each use and thus must be discarded) and its expense. A microcontact probe has recently been developed for use with the Nd:YAG laser. This works in principle much like the sapphire tip. It is used in contact with the target tissue and is disposable; however, the cost of fiber is approximately one third that of the sapphire tip. Potassium-Titanyl-Phosphate Laser
The active medium in the KTP laser is the same as an Nd:YAG laser. The wavelength of the KTP laser is 532 nm (one half of the wavelength of the Nd:YAG laser), which is a result of the beam passing through a KTP crystal. The KTP laser has a wavelength similar to the argon laser and thus has similar characteristics. The beam, delivered through a quartz fiber, has a primary effect of vaporization when the fiber is in contact with the tissue. As the distance between the fiber and the tissue increases, the primary effect becomes coagulation. The main disadvantage of the KTP laser is the need for the use of a filter because irreparable retinal damage can occur through an unprotected laparoscope via back scatter. Argon Laser
The argon laser has a wavelength of 514 nm and thus the scatter to absorption ratio is somewhat dependent on the color of the target tissue. Treatment of endometriosis with the argon laser is most efficient in coagulation or vaporization of pigmented lesions. 44 Recent studies have, however, shown that a significant percentage of endometrial lesions are nonpigmented. 1,19,45 Another potential clinical use of the argon laser would be in excitation of hematoporphyrin in photodynamic therapy. In summary, the goal in the treatment of superficial endometriosis is selective ablation of endometrial implants while simultaneously preservin~ the surrounding healthy tissue. The decision to mechanically excise (with the knife or scissors) or to use electrocauterization, endocoagulation, or one of the currently available surgical lasers should be based on the clinical situation and the operator's skill in the use of these instruments. There is no Vol. 55, No.4, April 1991
evidence that anyone of these treatment modalities is more successful than another in affecting the end result (e.g., pregnancy or relief of pain). The selection of modality and surgical technique, therefore, depend on the skill of the operator and the location and nature of the lesion. TREATMENT OF ADVANCED ENDOMETRIOSIS
Treatment of advanced endometriosis includes ablation of deep or retroperitoneal endometriosis and correction of abnormal pelvic anatomy, including adhesiolysis, ovarian cystectomy, oophorectomy, salpingectomy, and tubal reconstruction. In the majority of cases, these conditions are best treated by operative laparoscopy. Surgical treatment at laparotomy is required in cases in which technical limitations preclude operative laparoscopy. Adhesiolysis
The range of adhesions encountered in patients with endometriosis varies from transparent, avascular adhesions to extremely dense, cohesive adhesions that completely obliterate the tissue planes. The basic surgical maxim, to operate with minimal tissue trauma, applies to laparoscopic lysis of adhesions. Forceful blunt dissection of adhesions, which is successful but leaves a bloody, traumatized field, invariably results in reformation of adhesions and is thus unacceptable. Laparoscopic lysis of adhesions must be a meticulous delicate process with minimal trauma to the tissue and complete hemostasis. Transparent, avascular adhesions, which approximate two structures, may be lysed by delicate pressure, with scissors or aquadissection. When adhesions are dense and cohesive, a combination of blunt and sharp dissection is used. As the adhesions become more vascular, bleeding will be encountered and hemostasis should be accomplished using one of the coagulation methods described above. In the presence of vascular adhesions in which there is a space between the two structures, vessels encountered along the transection line should be coagulated before division. Dense adhesions may be lysed sharply or with a surgical laser while on "the stretch."46 Use of the surgical laser for adhesiolysis offers the advantages of (1) simultaneous coagulation of small vessels/capillaries during lysis of adhesions (Nd:YAG laser> CO 2 laser) and (2) improved visualization of the surgical field (scissors used through the operating channel of the laparoscope partially occlude the operating field).47 Cook and Rock
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Technical difficulties arise in limitation of the approach to the surgical field and inability to palpate the tissue. If necessary, one can use the second or third puncture site to insert a 5-mm laparoscope to gain a different field of view to better identify the tissue planes. Vital structures that may be involved in the adhesive complex (e.g., bowel, ureter, or vessels) must be clearly identified before dissection. If this is not possible, laparotomy is indicated. Secondlook laparoscopy may playa vital role in minimizing . a dh' 4849 postoperative eSlOns.' Resection of an Ovarian Endometrioma
Resection of endometriomas < 3 cm frequently occurs at laparoscopy. Endoscopic resection oflarger endometriomas is feasible. Factors that limit the size of endometriomas that can be resected are primarily related to the technical limitations experienced in endoscopic surgery. Endoscopic resection of endometriomas can be performed using two basic methods. The first method involves exposure, aspiration of contents, and removal of the cyst capsule. The second method requires dissection of the intact cyst with subsequent drainage and removal through the laparoscope. Simple drainage of the endometrioma is not adequate; the cyst wall must be excised or ablated. 50.51 Some authors feel that all periovarian adhesions must be removed before resection of the endometrioma. 52 If the adhesions do not limit access or visualization of the surgical field, they may actually make dissection of the endometrioma easier by holding the ovary in place and thus allow the surgeon to use the instruments for dissection rather than for retraction. Therefore, in select cases the periovarian adhesions may be lysed after resection of an endometrioma. Using the first method, the ovarian capsule overlying the endometrioma is incised. The cyst is drained, the ovarian capsule is stabilized with atraumatic forceps, and the cyst wall is grasped with forceps and peeled out with a corkscrew maneuver (Fig. 4). Occasionally, the cyst wall is friable and difficult to remove. If this situation is encountered, blunt and sharp dissection of the cyst from the ovarian capsule may be needed. Vessels encountered during removal of the cyst should be coagulated with the bipolar cautery before transection. If the cyst cannot be removed completely, remaining fragments of the cyst wall should be vaporized with the laser or fulgurated with electrocautery.51 Alternatively, the cyst can be shelled out intact using traction with sharp and blunt dissection while avoiding traumatizing the ovarian cortex. When the 670
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Laparoscapic treatment af endometriosis
Figure 4 Laparoscopic dissection of a cyst wall from the ovarian cortex, (From Vancaillie and Schenken. 37 Reproduced with permission of the publisher).
cyst is removed from the ovary, it is drained and removed through the laparoscope. This latter technique allows for better visualization of the tissue plane and assures complete removal of the cyst wall. Through the open abdomen, after an ovarian cystectomy, the edges of the ovarian cortex should be reapproximated using microsurgical techniques to close the defect and thus prevent adhesion formation to the raw surface. Sutures should not penetrate the ovarian capsule, thus a subcortical closure is recommended. A recent study by Brumsted et aI.,53 using a rabbit model suggests these techniques may be unnecessary. The authors found that if the ovarian cortex was left open, after a wedge resection, adhesion formation was less (but not significant) than if the cortex was reapproximated using microsurgical techniques. Comparison of surgical techniques used to perform the wedge resection (cold knife versus Nd:YAG laser) failed to show a difference in postoperative adhesion formation. These data suggest that endometriomas may be removed endoscopically and the defect left open, provided that the cyst wall can be completely removed with atraumatic techniques. However, because there is no supportive evidence in the human, this issue should be addressed through investigations with randomized controlled studies. Laparoscopic Salpingectomy
If the fallopian tube has been irreparably damaged in a patient undergoing laparoscopic treatment of Fertility and Sterility
endometriosis, the decision may be made to perform a salpingectomy. One of two techniques may be used to perform a laparoscopic salpingectomy. The fallopian tube should be adhesion-free before performing the salpingectomy. The fallopian tube may be doubly ligated with endoloop sutures and excised with the laparoscopic scissors. Alternatively, the fallopian tube and mesosalpinx may be serially electrocoagulated with the bipolar forceps and cut with the laparoscopic scissors. A combination of the above methods has also been applied successfully. Laparoscopic Oophorectomy
Occasionally, treatment of a patient for endometriosis will involve removal of one or both ovaries. Most commonly, this would apply to the patient who has chronic pelvic pain secondary to ovarian endometriosis and has completed her family. Rarely, the ovary is functionally destroyed and is removed to prevent further adhesion formation. The infundibulopelvic ligament may be ligated with three endoloop sutures and then transected. Alternatively, serial coagulation or clips using a laparoscopic stapling device may be used for hemostasis before cutting vascular pedicles. The ovary is then morcellated. Laparoscopic Tubal Reconstruction
Peritubal adhesions and tubal damage along the length of the fallopian tube may be encountered in patients with advanced endometriosis. Endometri0sis and sequelae of pelvic inflammatory disease may coexist and result in tubal occlusion. Tubal obstruction, however, rarely occurs solely as a result of involvement with endometriosis. If obstruction is present, it is often associated with extensive adhesion formation, ovarian, and peritoneal endometri0sis. Laparoscopic tubal reconstruction includes salpingo-ovariolysis, fimbrioplasty, and neosalpingostomy.54-58 The role oflaparoscopic neosalpingostomy is one of the most controversial areas of operative laparoscopy. The central issue to laparoscopic neosalpingostomy is comparative PRs with laparotomy.59-61 The overall reported PR after laparoscopic neosalpingostomy is approximately 27%; however, these studies either exclude patients with endometriosis or do not specify if endometriosis is a factor. 62- 65 There are few data regarding the extent to which laparoscopic neosalpingostomy alters fertility of patients with endometriosis-associated tubal obstruction. Treatment of Retroperitoneal and Deep Endometriosis
Deep (>5 mm) and very deep (>10 mm) endometrial implants represent a very active form of enVol. 55, No.4, April 1991
dometriosis. Estimation ofthe depth of endometrial implants at the time of laparoscopic resection correlate well with histologic measurements. 2The depth of penetration of endometrial implants roughly correlates with the percent of patients presenting with pelvic pain. Very deep implants have been demonstrated exclusively in patients with pain.2 Endometriosis infiltrates through the septa of loose connective tissue and is stopped by adipose tissue. This is probably the reason deep endometriosis is found in the posterior cul-de-sac and the uterosacralligaments but not in the ovarian fossa. 2 In addition to visualization, the diagnosis of retroperitoneal endometriosis is made by preoperative rectovaginal palpation and blunt probe palpation. 66 Laparoscopic treatment of retroperitoneal and deep endometriosis is often complicated by close proximity of vital structures (e.g., ureter, bladder, or vessels). The use of hydrodissection has recently been reported. 67 Hydrodissection may be used in conjunction with any surgical modality. A small hole is created in the peritoneum, and a sufficient amount of lactated Ringer's solution is injected retroperitoneally with the hydrodissection system. This technique provides two functions: (1) separation of the lesion from underlying structures and (2) buffer action to protect underlying structures from thermal damage from the surgical laser (the water disperses the thermal energy of the laser). Peritoneal endometriosis overlying a vital structure can be safely vaporized after hydrodissection. If the electrocautery is used, this technique reduces, but does not eliminate, the transmission of current. Endometriosis that superficially involves the muscularis of the bowel or bladder (but is not full thickness, as determined by preoperative cystoscopy and colonoscopy) may be ablated by laser vaporization. If retroperitoneal disease is present, the laser or laparoscopic scissors may be used to incise the peritoneum, the retroperitoneum may then be explored, and all implants ablated or excised. Peritoneal windows are usually associated with endometriosis, and thus the edges of the window should be opened and vaporized even if they appear grossly norma1. 21 ,22,68 This can be safely accomplished with a buffer of retroperitoneal water. If the lesions cannot be adequately isolated or completely ablated, laparotomy or adjunctive medical therapy should be considered. Retroperitoneal dissection may be facilitated by placing a bougie in the rectum and sponge forceps in the vagina. Traction in either direction may help open the rectovaginal and pararectal spaces. Care should be taken to develop the spaces and to identify Cook and Rock
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the ureter before coagulation or vaporization of disease. These safeguards apply to surgery performed through the open abdomen or through the laparoscope. Laparoscopic Uterosacral Transection
Transection of the uterosacral ligaments for relief of dysmenorrhea was originally described by Ruggi and Crosser. 69 More recently, Doyle70 and Doyle and Des Rosiers 71 have discussed the use of paracervical uterine denervation for the relief of dysmenorrhea and pelvic pain. Frangenheim and Kleindienst 72 were the first to propose laparoscopic transection of the uterosacral ligaments, but they had no data to demonstrate efficacy of this treatment modality. Feste73 reported a series of patients who were treated by laparoscopic laser ablation of the uterosacralligaments for relief of dysmenorrhea. Seventy-one percent of the 42 patients treated with laser neurectomy had little or no dysmenorrhea 1 year after treatment. Lichten and Bombard74 utilized bipolar cautery and transection of the uterosacral ligaments in a double-blind study of21 patients (11 treatment, 10 control). Significant improvement or relief of symptoms was noted in 9 of 11 patients 3 months postoperatively and in 5 patients after 1 year. None of the patients in the control group experienced relief of dysmenorrhea. A significant difference (P < 0.02) was observed at both 3 and 12 months postoperatively. Relief of pain may also be related to the ablation of uterosacral endometriosis at the time of transection. Seventy-five percent of 80 patients with endometriosis undergoing laparoscopic ablation of the uterosacral ligaments with the KTP laser in an uncontrolled study reported improved symptoms at 6 months of follow-up.65 The efficacy of this procedure should be established through well-designed randomized clinical trials. SUCCESS IN THE TREATMENT OF ENDOMETRIOSIS
Successful treatment of endometriosis can be defined as either attainment of a viable pregnancy or alleviation of pain. The nature of endometriosis is such that a significant portion of patients treated for pain experience recurrence of symptoms. Success, therefore, is additionally defined as the length of time the patient is symptom free and the percentage of patients that experience recurrence. Determination of the success rates of the various treatment modalities for endometriosis is difficult for several reasons, including: (1) numerous classifications systems; (2) lack of randomized prospective trials; (3) common use ofthe crude PR; and (4) lack 672
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of controls. Numerous classification systems have been used over the years, with the most recent classification system adopted in 1985.32 Thus, comparison of a consistent group or subset of patients with various degrees of severity of endometriosis is difficult. To date, no comprehensive prospective randomized clinical trial has been performed. Indeed, such a trial would require randomization of patients with the various stages of endometriosis with each of the currently available treatment modalities (expectant management, medical treatment, surgical treatment). The vast majority of articles in the literature report the success rate based on the crude PRo The crude PR is the number of patients who attain pregnancy divided by the number of patients treated. Therefore, a study with a longer follow-up period will have a more successful outcome than a study with a shorter follow-up period. Retrospective studies with varying lengths of patient follow-up may reflect different success rates related solely to this factor. Several different statistical models are available to help compensate for this factor including life table analysis and monthly fecundity rate. 75-80 These statistical models must be instituted routinely in future publications if we are to truly gain an appreciation for the success of a particular treatment modality as compared with a previous form of treatment. It is presumed that the presence of endometriosis results in a reduction, but not an elimination, of the fertility potential of an individual. Therefore, evaluation of a treatment modality must judge treatment success against the baseline PR (a control group). The use of operative laparoscopy for the treatment of endometriosis may involve resection or ablation of the endometrial implants with electrocautery, endothermy, or various surgical lasers, and restoration of normal anatomy.8! The majority of published reports describing the use of laparoscopy for the treatment of endometriosis involves less severe forms of the disease (e.g., stage I and 11). Thus, much ofthe debate in the literature revolves around which laparoscopic method of ablation (electrocautery, endocoagulation, or laser) of superficial implants is most successful. More recently, operative laparoscopy has assumed a progressively larger role in the treatment of advanced cases of endometriosis with correction of abnormal pelvic anatomy.65 The debate then focuses on what extent of disease should be treated through the laparoscope rather than through the open abdomen. Laparoscopic Treatment Utilizing Electrocautery
Laparoscopic treatment of endometriosis to enhance fertility initially utilized electrocautery for coagulation of endometrial implants.82 The overall Fertility and Sterility
crude PR reported in the literature, using this treatment modality irrespective of the stage of endometriosis, is 52%. The crude PR for minimal, mild, and moderate endometriosis is 64%, 52% and 36%, respectively (Table 4). The crude PR for severe endometriosis is 50%; however, this is based on two small studies with four of eight patients becoming pregnant. 84 ,90 The first reported use of endoscopic treatment of endometriosis with electrocautery was by Eward in 1978.82 Overall, 24 of 43 patients in this study became pregnant. Only two of the studies in the literature on laparoscopic treatment of endometriosis with electrocautery used a control group (expectant management). In the first of these two studies, 28 patients with endometriosis documented at laparoscopy presented with complaints of infertility or pelvic pain. 84 Nineteen patients underwent fulguration of endometriosis with electrocautery (11 patients with pelvic pain and 8 with infertility), whereas the other 9 patients (5 with pain and 4 with infertility) did not receive electrocautery. In the treatment group, 6 of 8 patients became pregnant and 7 of 11 patients experienced complete relief of pain, whereas in the control group only 1 of 4 patients became pregnant and 1 of 5 patients with pain had relief. The number of patients in this study is too small to be statistically significant. The second study that used a control group was a prospective randomized study of patients with mild endometriosis by Nowroozi et al. 89 One hundred twenty-three patients underwent laparoscopy and were assigned to either the treatment group, in which the endometrial implants were coagulated using electrocautery, or the control group, in which the endometrial Table 4
implants were left intact. Forty-two of 69 patients in the treatment group (60.8%) became pregnant, whereas only 10 of 54 (18.5%) patients in the control group became pregnant after 8 months. Laparoscopic cauterization of endometriosis may increase the rate at which patients initially become pregnant. Sulewski et al. 85 treated 100 consecutive patients with mild or moderate endometriosis with laparoscopic electrocautery. This resulted in a crude PR of 40% over a 37-month follow-up. Of the 40 patients who became pregnant, 73% of the pregnancies occurred in the 1st 6 months and 88% of the pregnancies occurred in the 1st twelve months, which is higher than traditionally reported with medical treatment or laparotomy. Seventy-five percent of pregnancies after laparoscopic resection of an endometrioma occurred within the first six months. 50 No significant difference was noted between treatment with danazol and laparoscopic electrocautery. Seiler et al. 88 randomized patients with moderate endometriosis between danazol therapy and electrocoagulation of endometrial implants. The danazol group experienced pregnancy in 16 of 41 patients (39%), whereas the electrocautery group experienced pregnancy in 20 of 45 patients (44%) over a 7-month period of follow-up. Murphy et al.,90 using life table analysis and the two-parameter exponential method, studied 72 patients with stage I or stage II endometriosis who underwent laparoscopic electrocoagulation of the endometrial implants. The crude PR with an average follow-up period of 7.9 months was 74% for stage I and 57% for stage II. The estimated cure rates, using the two-parameter model, for stage I and II were
Pregnancy Rates After Laparoscopic Electrocoagulation of Endometriosis No. of pregnancies/no. treated
Author
Minimal
Mild
Moderate
Severe
Combined
Length of follow-up mo
Eward82 Hasson84,c Sulewski et al.85,d Daniell and PittawayBS Reich and McGiynn50 Seiler et al. 88" Nowroozi et al. 89.t Murphy et al.oo.t Total
4/7
(57)a
10/18 (56)b
0/1 (0) 20/42 (48)
4/5 (80)
24/36 (67)
20/45 (44) 42/69 (61) 18/36 (50)
2/7 (29)
0/3 (0)
28/44 (64)
110/210 (52)
24/67 (36)
4/8 (50)
a Values in parentheses are percents. Stage I by classification system of Mitchell and Farber.83 b Stage II by classification system of Mitchell and Farber. 83 C Clinical judgment used to evaluate the extent of disease: 1 = minimal; 2 = moderate; 3 = fairly extensive.
Vol. 55, No.4, April 1991
2/2 (100) 20/58 (35)
14/25 6/8 40/100 33/60 15/23 20/45 42/69 44/82
(56) (75) (40) (55) (65) (44) (61) (54)
13 7 37 18 7 8 8
214/412 (52)
Classification system not specified. Acosta classification system used. 87 f The Revised American Fertility Society classification system used. 32 d
e
Cook and Rock
Laparoscopic treatment of endometriosis
673
98.2% and 76.6%, respectively. The monthly fecundity for patients with endometriosis was only 10.3% for stage I and 7.59% for stage II. It is interesting to note that the majority of pregnancies in this study occurred within the 1st 6 months (71 %). Laparoscopic Treatment Utilizing Endocoagulation
Endocoagulation of endometrial implants has not been studied as widely in the English literature as electrocautery or laser vaporization. 35,62 Forty percent of 90 women with endometriosis treated with operative endoscopy and endocoagulation became pregnant.62 Laparoscopic Treatment Utilizing the Surgical Laser
The CO 2 laser has recently been the most widely used surgical laser for the treatment of endometriOSiS. 91 - 101 Use of the surgical laser in conjunction with operative laparoscopy offers the theoretical advantage of a more selective ablation of the endometrial implants while preserving normal tissue.102 The N d: YAG, argon, and KTP lasers have also been used to treat endometriosis. 43 ,103-105 Use of the surgicallaser has not improved the crude PR in comparison with other methods of ablation of endometriosis. The overall crude PR described in the literature for laparoscopic CO 2 laser vaporization of endometriosis is 59%, which is similar to the 52% described for both treatment at laparotomy and laparoscopic electrocoagulation of endometriosis. The overall crude PR reported in the literature for stage I, stage II, stage III, and stage IV is 59%, 58%, 58%, and 64%, respectively (Table 5). The results for stage IV are derived primarily from one study.ll2 Bruhat et al. 114 were the first to publish the use of the CO 2 laser through the laparoscope in 1979 followed by Tadir et al. ll5 in 1981. Use of the laparoscopic CO 2 laser in the United States was first reported in 1982 in both rabbits and 10 humans with mild or moderate endometriosis. The length of follow-up and the success rate (PR) were not reported. 101 Kelly and Roberts 100 were among the first to report PRs of patients with endometriosis treated laparoscopically with the CO 2 laser. A 6-month follow-up of 10 patients with stage I and II endometriosis resulted in a 60% crude PR. 1OO This study showed that laparoseopic treatment of endometriosis with the CO 2 laser was a viable alternative. Feste73 published the first large study describing his experience with laser laparoseopy of 202 patients, including laser transection of the uterosacral liga674
Cook and Rock
Laparoscopic treatment of endometriosis
ments and vaporization of endometriotic implants on the bladder and bowel. A laser, 1 cm by 1 em, ablation of the uterosacral ligaments was performed on 42 patients with dysmenorrhea. Seventy-one percent of the patients had minimal or no dysmenorrhea after the procedure, whereas 23% had no change in symptoms and 4 % had worse symptoms. He also reported a 72% crude PR in 58 patients with stage I and II endometriosis, without other factors, treated by laparoscopic CO 2 laser with a follow-up period of 1 year. As late as 1985, a report was published that stated that laser laparoscopy was an effective form of treatment. 1OO This study required the use of a second 10-mm puncture site for delivery of the laser beam with a 2-mm spot size and power densities of 400 to 600 W /cm2' Martin published two similar reports in 1985 and 1986. 102 ,107 The data of the first study were included in the second. Thirty-four patients with endometriosis (stage I, II, or III) as the only identifiable etiology of infertility experienced an overall PR of 68% with a follow-up period of 12 to 44 months. Eighty-one additional patients with other associated infertility factors had a crude PR of 40% with the same follow-up period. Nezhat et al.97,112,116 have published a series of articles describing their clinical experience with videomonitoring systems and laparoscopic CO 2 laser vaporization of endometriosis. All patients were classified using the original AFS classification system. 113 A crude PR of 75.1%,62.7%,42.1%, and 50% for stages I, II, III, and IV, respectively, was reported in the initial series of 102 patients with an 18-month follow-up.97 The most recent study observed a crude PR of 71.8%,69.8%, 67.2%, and 68.6% for stages I, II, III, and IV, respectively, in a total of 243 patients. 112 The length of follow-up was not specified in the latter report, however, in the initial study 66% of the pregnancies occurred in the 1st 8 months after treatment, 29% 8 to 12 months after treatment, and only 5% 12 to 18 months after treatment. The majority of pregnancies occurred within the 1st 6 months after treatment, similar to the findings of Sulewski et al. 85 and Murphy et a1. 90 with laparoscopic electrocoagulation of endometriosis. The first study to use the R-AFS classification system32 reported an overall crude PR of 57% after 15 months of follow-up.96 The PRs for stages I to II, III, and IV were 64.5%, 57.7%, and 28.8%, respectively. Endometriomas were treated ifpenetration into the ovary was <3 cm. Patients were excluded from the study if the endometrioma was >5 cm in diameter. The cyst was aspirated and the cyst wall vaporized with the CO 2 laser. Fertility and Sterility
Table 5
Pregnancy Rates After Laparoscopic CO 2 Laser Vaporization of Endometriosis· No. of pregnancies/no. treated Stage I
Author
Stage II
Stage IV
Stage III
Length of follow-up
Combined
mo
Daniell and Brown 'OI Daniell and PittawayBS Kelly and Roberts 'OO Chong'06 Feste 73 Martin 102 Martin '07 Davis96•e Olive and Martin '08•f Donnez '09 •• Paulsen and Asmer95 •• Gast et al. 110,. Fayez et aU"·c Nezhat et al. '12•• Total
3/3 21/32 24/47 7/27 25/56
(100)
3/7
(43)
(66)b
(51) (26)
4/6 (66) 3/19 (16) (45)d 22/45 (49)d 20/31 (65)
2/5 1/4 9/14 15/26
(40) (25)C (64)C
(58)
2/7 (29)
3/10
(30)
5
3/15
(20)
6
6/10 21/32 30/58 11/50 56/115 37/64
(60) (66) (52) (22) (49) (58)
6 12 12 9 12 15
23/59 (39) 26/42 (62)
22/48 (46) 11/21 (52)
10/20 (50) 3/7 (43)
55/127 (43) 40/70 (57)
18
109/140 (78) 36/70 (51) 27/38 (71)
60/88 (68) 12/33 (38) 33/44 (75)
9/19 (47)
169/228 (74) 50/122 (41) 60/82 (73)
8 to 32 10 12
28/39 (72)
60/86 (70)
45/67 (67)
35/51 (69)
168/243 (69)
329/553 (59)
230/397 (58)
94/162 (58)
37/58 (64)
690/1170 (59)
• Values in parentheses are percents. The original American Fertility Society classification system is used unless noted. ll3 b Postop danazol X 132 days. c Postop danazol X 6 months. d 3-month course of danazol6 to 18 months postop if not pregnant.
Revised American Fertility Society classification system. 32 Patients treated with either a combination of laser laparoscopy only or a combination of laser laparoscopy and preop or postop danazol. • Patients with factors other than endometriosis excluded from study.
A large retrospective study by Olive and Martin 108 is one of the few in the literature using more in depth statistical analysis. Patient groups analyzed included: endometriosis only, endometriosis with other factors, the stage of endometriosis, and treatment with laser laparoscopy only or in combination with danazol treatment. Kaplan Meyer life table analysis was performed with monthly fecundity rates. There was no significant difference in the predicted PRs at 1, 2, or 3 years by stage of endometriosis. There were no statistically significant differences among any of the subgroups and the monthly fecundity rates. The monthly fecundity rates of stage I and stage II endometriosis with laser laparoscopy were comparable with those found with expectant management, danazol, and conservative surgery. It is interesting to note that the monthly fecundity rate in stage III endometriosis is 4.5%, whereas that observed with danazol and conservative surgery is approximately 1.5%. Using the two-parameter exponential model of Guzick and Rock,77 cumulative PRs of patients treated with laser laparoscopy are approximately the same as those observed with conservative surgery and danazol. It is also interesting to note that cu-
mulative PRs for stage I and stage II endometriosis treated with laser laparoscopy, danazol, and conservative surgery, as determined by the two-parameter exponential model, reveals a much higher initial cumulative PR with laser laparoscopy than with the other two treatment modalities (Fig. 5). Another retrospective study of 70 patients without controls, yielded crude PRs at 18 months of 62%,
Vol. 55, No.4, April 1991
e
f
0.7 0.6 ~
~
o.s
>
~
~
0.4
I 0.3 ~
;;;
~
(i
0.2
- . - . - LMer l8piIroecopy --------- ~ Surgery
0.0
o
, 6
12
,
1.
---00".,,,
,
,
,
24
30
31
Months
Figure 5 Cumulative PRs of patients with endometriosis treated with laparoscopic surgery, laparotomy, or danazol. (From Olive and Martin. 'OB Reproduced with permission of the publisher, The American Fertility Society).
Cook and Rock
Laparoscopic treatment of endometriosis
675
52%, and 42% for AFS stages I, II, and III, respectively.109 Gast et al. 110 studied 122 patients, 95 with at least one contributing factor in addition to endometriosis, using the R-AFS classification system. With a follow-up period of 2 to 32 months, the corrected crude PRs were 61 %,47%, and 54%, and the uncorrected crude PRs were 51 %,38%, and 47% for stages I, II, and III, respectively. No pregnancies occurred after 18 months of follow-up. Fayez et a1. 111 performed a retrospective study comparing the results of 238 patients with minimal and mild endometriosis treated with laparoscopy alone, danazol alone, or a combination of laparoscopy and danazol. The combination group used danazol postoperatively, 800 mg/d, for 6 months. The crude PRs for patients with minimal endometriosis treated with laparoscopy, danazol, and a combination of the two was 71%, 28%, and 55%, respectively. The crude PRs for patients with mild endometriosis were 75%, 25%, and 52%, respectively. The majority of pregnancies occurred within the 1st 6 months post-treatment. Second-look laparoscopy showed complete resolution of endometriosis in 84%, 0%, and 75%, respectively, of patients treated with laparoscopy, danazol, and a combination of the two.
of patients treated with operative laparoscopy become pregnant within the 1st 6 months after treatment.85,90,97,108 The monthly fecundity rates with laser laparoscopy alone or combination therapy are similar (Table 6). In light of the potential disadvantages of preoperative medical therapy and the lack of objective data demonstrating efficacy, the use of preoperative medical therapy may be best reserved for patients with severe disease in which preoperative medical treatment may allow for less extensive resection of disease and preservation of reproductive system. Postoperative medical therapy offers the theoretical advantage of eradicating residual or microscopic disease. The results of studies using postoperative danazol in patients with severe endometriosis are contradictory with both decreased and increased PRs in comparison with surgery aloneY7,1l8 Because most patients become pregnant within the first 6 months after laparoscopic treatment of endometriosis, postoperative medical treatment is probably best reserved for patients with residual disease or patients who are not actively pursuing pregnancy during this period. THE FUTURE
Combination Therapy
Combination treatment of endometriosis involves the use of either preoperative or postoperative medical treatment in an effort to improve treatment success. The use of preoperative medical treatment suppresses ovarian activity so that cystic structures related to ovulatory activity are not confused with endometriosis. Preoperative medical treatment also results in decreased inflammation, vascularity, and size of implants, which may allow for less extensive resection at surgery and potentially less adhesion formation. The potential disadvantages of preoperative medical treatment include: (1) the appearance of endometriosis during medical treatment may be more difficult to diagnose, resulting in a less complete resection; (2) the cost and potential side effects of medical treatment; and (3) the delay in the time to which the patient can begin to attempt pregnancy.53 Postoperative medical therapy may be beneficial if complete resection of endometriotic lesions cannot be accomplished or to eradicate remaining microscopic disease. The presence of microscopic disease has been demonstrated in normal appearing peritoneum and may contribute to both treatment failure and recurrence of endometriosis. 25 Postoperative medical treatment precludes the patient attempting pregnancy the 1st 6 months. The majority 676
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Laparoscopic treatment of endometriosis
Fiber Optic Microendoscopy
Endoscopic surgery is rapidly evolving. Current technological developments may revolutionize the diagnosis and treatment of endometriosis. The currently available laparoscopes use a lens system developed by Dr. Hopkins in the 1960s. 119 The major
Table 6 Monthly Fecundity Rates With Laser Laparoscopy and Adjunctive Therapy·
Disease severity and treatment
No, of patients
Monthly fecundity rate
95% confidence limits %
Stage I endometriosis Laser only Preoperative danazol Postoperative danazol Stage II Laser only Preoperative danazol Postoperative danazol Stage III Laser only Preoperative danazol Postoperative danazol
44 13 2
3.5 1.6 3.5
1.8 to 4.9 o to 3,1 o to 10.2
22 21 5
2.5 4.4 2.5
0.7 to 4.4 2.0 to 6.8 o to 4.4
12 4 4
5.6 6.1 1.5
1.5 to 10.1 o to 14.5 o to 4.4
• Adapted from Olive and MartinYlS (Reproduced with permission of the publisher, The American Fertility Society).
Fertility and Sterility
disadvantage of this type of laparoscope is that it requires the use of general anesthesia. Fiber optic endoscopes are being developed with diameters as small as 0.25 mm. The diameter of the individual fibers in a fiber optic bundle is becoming smaller (the current limit is about 6 ~m), which allows for more elements in a given bundle size and thus increased resolution. In the future, diagnosis and staging of endometriosis may, be made in the office with local anesthesia and the fiber optic endoscope. The best treatment modality could then be selected before the need for general anesthesia. The potential even exists for the treatment of endometriosis at the time of microendoscopy with photodynamic therapy. Photodynamic Therapy
Photodynamic therapy is an experimental technique that may be used in conjunction with the laparoscope for the treatment of endometriosis in the future. This process utilizes selectively absorbed photosensitive chemicals that cause tissue destruction when exposed to a certain wavelength of light. The photosensitive chemical used currently is a purified hematoporphyrin derivative, dihematoporphyrin ether (DHE).120 A recent study used rabbit endometrial transplants to evaluate the potential use of photodynamic therapy in the treatment of endometriosis. l2l The animals were intravenously injected with DHE and exposed to 630 nm light (argon laser) 24 hours later. A power density of 100 J/cm2 resulted in complete destruction of 81 % of the transplants. There was no tissue destruction in the control animals that did not receive DHE but were exposed to the argon laser. The results of these studies using animal models are encouraging, however, further studies are needed before one can extrapolate these results to patients with endometriosis in the clinical setting.
of anatomic damage secondary to endometriosis is continually expanding. The experience of the surgeon is paramount in overcoming the technical difficulties encountered in endoscopic surgery. The primary advantage of the surgical laser lies in a more controlled penetration of tissue. Discussion pertaining to which treatment modality (excision, endocoagulation, electrocautery, or anyone of the various types of lasers) is most successful in the treatment of superficial endometriosis is missing the central issue. It does not matter how the endometriosis is ablated (all of the various treatment modalities available are capable of ablating endometriotic lesions). The critical issue is the ability of the surgeon to correctly identify endometriosis with its wide range of appearances and to utilize the various treatment modalities correctly to fully treat the disease. Variation in the success of reports utilizing different modes of ablation of superficial endometriosis is most likely related to a difference in the patient population, the skill of the surgeon, or inadequate statistical analysis. The most common form of statistical analysis used in reporting and comparing the success rates in the treatment of endometriosis has been the crude PRo The time has come to discard this outmoded and inaccurate definition of success. Both as individuals and as a group of physicians providing care to the infertile patient, we strive to provide the patient with the form of treatment that is most efficacious. The continued use of the crude PR as the primary statistical tool makes comparison of results difficult and hinders identification of successful treatment modalities. We call for inclusion of uniform in depth statistical analysis, including monthly fecundity, life table analysis, and two-parameter exponential analysis in future publications. This will allow for clarification of treatment success and continue to promote the advancement of the patient care provided by this medical subspecialty.
CONCLUSIONS
Laparoscopic treatment of endometriosis offers several advantages over other forms of therapy. The patient will usually undergo laparoscopy for diagnosis of endometriosis and thus can be treated without having to undergo a second surgical procedure. In addition, the patient does not have to accept the extended time or potential side effects of medical treatment. Laparoscopic treatment of endometriosis clearly results in reduced length of hospital stay and cost in comparison with laparotomy. The role of laparoscopic surgery in the correction Vol. 55, No.4, April 1991
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nancy with operative laparoscopy for endometriosis in an in vitro fertilization program. Fertil Steril 50:463, 1988 Wood G P: Laparoscopic examination of the normal infertile woman. Obstet Gynecol 62:642, 1983 Surrey MW, Friedman S: Second-look laparoscopy after reconstructive pelvic surgery for infertility. J Reprod Med 27: 658, 1982 Cohen MR: Laparoscopy in the diagnosis and management of endometriosis. J Reprod Med 27:240, 1982 McBride N, Newman RL: Diagnostic laparoscopy. Int J Gynaecol Obstet 15:556, 1978 Semchyshyn S, Strickler RC: Laparoscopy: is it replacing clinical acumen? Obstet GynecoI48:615, 1976 Nezhat C, Winer WK, Cooper JD, Nezhat F: Endoscopic infertility surgery. J Reprod Med 34:127, 1989 Gomel V: Salpingo-ovariolysis by laparoscopy in infertility. Fertil Steril 40:607, 1983 Gomel V: Principles of infertility microsurgery. In Microsurgery in Female Infertility. Boston, Little, Brown and Co, 1983, p 143 Nezhat CR, Nezhat FR, Metzger DA, Luciano AA: Adhesion reformation after reproductive surgery by videolaseroscopy. Fertil Steril 53:1008, 1990 Filmer S, Gomel V, McComb PF: Operative laparoscopy versus open abdominal surgery: a comparative study on postoperative adhesion formation in the rat model. Fertil SteriI48:486,1987 Luciano AA, Maier DB, Koch EI, Nulsen JC, Whitman GF: A comparative study of postoperative adhesions following laser surgery by laparoscopy versus laparotomy in the rabbit model. Obstet Gynecol 74:220, 1989 Jansen RPS: Early laparoscopy after pelvic operations to prevent adhesions: safety and efficacy. Fertil Steril 49:26, 1988 Martin DC, Vander Zwagg R: Excisional techniques for endometriosis with the CO 2 laser laparoscope. J Reprod Med 32:753, 1987 Jansen RP, Russell P: Nonpigmented endometriosis: clinical, laparoscopic, and pathologic definition. Am J Obstet Gynecol 155:1154, 1986 Redwine DB: Peritoneal blood painting: an aid in the diagnosis of endometriosis. Am J Obstet GynecoI161:865, 1989 Chatman DL, Zbella EA: Pelvic peritoneal defects and endometriosis: further observations. Fertil Steril46:711, 1986 Chatman DL: Pelvic peritoneal defects and endometriosis; Allen-Masters syndrome revisited. Fertil Steril36:751, 1981 Redwine DB: The distribution of endometriosis in the pelvis by age groups and fertility. Fertil Steril 47:173, 1987 Murphy AA, Guzick DS, Rock JA: Microscopic peritoneal endometriosis. (Letter) Fertil SteriI51:1072, 1989 Murphy AA, Green WR, Bobbie D, dela Cruz ZC, Rock JA: Unsuspected endometriosis documented by scanning elec· tron microscopy in visually normal peritoneum. Fertil Steril 46:522, 1986 Comillie FJ, Bronsens lA, Vasquez G, Riphagen I: Histologic and ultrastructural changes in human endometriotic implants treated with the antiprogesterone steroid erthylnorgestrienone (Gestrinone) during two months. Int J Gynecol Pathol 5:95, 1986 Brosens I, Vasquez G, Gordts S: Scanning electron microscopy study ofthe pelvic peritoneum in unexplained infertility and endometriosis. (Abstr. 48) Fertil Steril 41:21S, 1984 Vasques G, Comillie F, Brosens IA: Peritoneal endometri-
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osis: scanning electron microscopy and histology of minimal pelvic endometriotic lesions. Fertil Steril 42:696, 1984 Nisolle M, Paindaveine B, Bourdon A, Berliere M, CasanasRoux F, Donnez J: Histologic study of peritoneal endometriosis in infertile women. Fertil Steril 53:984, 1990 Wheeler JM, Malinak LR: Recurrent endometriosis: incidence, management, and prognosis. Am J Obstet Gynecol 146:247, 1983 Candiani GB, Vercellini P, Fedele L: Laparoscopic ovarian puncture for correct staging of endometriosis. Fertil Steril 53:994, 1990 The American Fertility Society: Revised American Fertility Society Classification of Endometriosis: 1985. Fertil Steril 43:351, 1985 Cushing H, Bovie WT: Electro-surgery as an aid to the removal of intracranial tumors. With a preliminary note on a new surgical-current generator. Surg Gynecol Obstet 47: 751, 1928 Ohlgisser M, Sorokin Y, Heifetz M: Gynecologic laparoscopy. A review article. Obstet Gynecol Surv 40:385, 1985 Semm K: The laparoscopic instrumentation. In Atlas of Gynecologic Laparoscopy and Hysteroscopy. Philadelphia, W.B. Saunders Co., 1977, p 30 Keye WR, Jr: Laparoscopic treatment of endometriosis. Obstet Gynecol Clin North Am 16:157, 1989 Vancaillie T, Schenken RS: Endoscopic surgery. In Endometriosis, Contemporary Concepts in Clinical Management, Edited by RS Schenken. Philadelphia, J.B. Lippincott Company, 1989, p 249 Fuller T A: Fundamentals of lasers in surgery and medicine. In Surgical Application of Lasers, 2nd edition, Edited by JA Dixon. Chicago, Yearbook Medical Publishers Inc., 1987, p 21 Fisher JC: Basic laser physics and interaction of laser light with soft tissue. In Endoscopic Laser Surgery Handbook, Edited by SM Shapshay. New York, Marcel Dekker Inc., 1987, p 118 Baggish MS, ElBakry MM: A flexible CO. laser fiber for operative laparoscopy. Fertil Steril 46:16, 1986 Shirk GJ: Use of the Nd:YAG laser for the treatment of endometriosis. Am J Obstet Gynecol 160:1344, 1989 Corson SL, Unger M, Kwa D, Batzer FR, Gocial B: Laparoscopic laser treatment of endometriosis with the Nd: YAG sapphire probe. Am J Obstet Gynecol 160:718, 1989 Brumsted JR, Shirk G: A second puncture probe for laparoscopic delivery of the Nd:YAG laser. Obstet Gynecol 73: 672, 1989 Keye WR, Jr, Hansen LW, Astin M, Poulson AM, Jr: Argon laser therapy of endometriosis: a review of 92 consecutive patients. Fertil Steril 47:208, 1987 Stripling MC, Martin DC, Chatman DL, Vander Zwaag R, Poston WM: Subtle appearance of pelvic endometriosis. Fertil Steril 49:427, 1988 Gomel V: Operative laparoscopy: time for acceptance. Fertil Steril 52:1, 1989 Borten M, Friedman EA: Visual field obstruction in singlepuncture operative laparoscopy. J Reprod Med 31:1102, 1986 Pittaway DE, Daniell JF, Maxson WS: Ovarian surgery in an infertility patient as an indication for a short-interval second-look laparoscopy: a preliminary study. Fertil Steril 44:611, 1985 McLaughlin DS: Evaluation of adhesion reformation by early second-look laparoscopy following microlaser ovarian wedge resection. Fertil Steril 42:531, 1984 Reich H, McGlynn F: Treatment of ovarian endometriomas
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using laparoscopic surgical techniques. J Reprod Med 31: 577, 1986 Corson SL, Unger M, Kwa D, Batzer FR, Gocial B: Laparoscopic laser treatment of endometriosis with the Nd: YAG sapphire probe. Am J Obstet Gynecol 160:718, 1989 Murphy AA: Operative laparoscopy. Fertil Steril47:1, 1987 Brumsted JR, Deaton J, Lavigne E, Riddick DH: Postoperative adhesion formation after ovarian wedge resection with and without ovarian reconstruction in the rabbit. Fertil Steril 53:723, 1990 Gomel V: Laparoscopic tubal surgery in infertility. Obstet GynecoI46:47,1975 Fayez JA: An assessment of the role of operative laparoscopy in tuboplasty. Fertil Steril 39:476, 1983 Bruhat MA, Mage G, Mandes H, Soualhat C, Ropert JF, Pouly JL: Laparoscopy procedures to promote fertility ovariolysis and salpingolysis: results of 93 selected cases. Acta Eur FertiI14:113, 1983 Gomel V, Taylor PJ, Yuzpe AA, Rioux JE: Laparoscopy and Hysteroscopy in Gynecologic Practice. Chicago, Year Book Medical Publishers, 1986, p 77 Bruhat MA, Mage G, Pouly JL: Use of the CO2 laser in neosalpingostomy. In Laser Surgery: Proceedings of the 3rd International Symposium on Laser Surgery, Edited by I Kaplan, PW Ascher. Tel Aviv, OT-PAZ Press, 1979, p 271 Rock JA, Karayama KP, Martin EJ, Woodruff JD, Jones HW, Jr: Factors influencing the success of salpingostomy techniques for distal fimbrial obstruction. Obstet Gynecol 52:591, 1978 Boer-Meisel ME, te Velde ER, Habbema JDF, Kardaun JWPF: Predicting the pregnancy outcome in patients treated for hydrosalpinx: a prospective study. Fertil Steril 45:23, 1986 Donnez J, Casanas-Roux F: Prognostic factors of fimbrial microsurgery. Fertil SteriI46:200, 1986 Mettler L, Giesel H, Semm K: Treatment of female infertility due to tubal obstruction by operative laparoscopy. Fertil Steril 32:384, 1979 Daniell JF, Herbert CM: Laparoscopic salpingectomy utilizing the CO 2 laser. Fertil Steril 41:558, 1984 Gomel V: Salpingostomy by laparoscopy. J Reprod Med 18: 265, 1977 Daniell JF: Laser laparoscopy: KTP. In Laser Surgery in Gynecology and Obstetrics, Edited by WR Keye, Jr. Chicago, Year Book Medical Publishers, 1990, p 222 Martin DC, Hubert GD, Levy BS: Depth of infiltration of endometriosis. J Gynecol Surg 5:55, 1989 Nezhat C, Nezhat FR: Safe laser endoscopic excision of vaporization of peritoneill endometriosis. Fertil Steril52:149, 1989 Dmowski WP: Pitfalls in clinical, laparoscopic and histologic diagnosis of endometriosis. Acta Obstet Gynecol Scand Suppl 123:61, 1984 Ruggi J, Crosser HS: Gynecology, Edited by J Ruggi, HS Crosser. St. Louis, C.V. Mosby, 1915 Doyle JB: Paracervical uterine denervation by transection of the cervical plexus for the relief of dysmenorrhea. Am J Obstet Gynecol 70:11, 1955 Doyle JB, Des Rosiers JJ: Paracervical uterine denervation for relief of pelvic pain. Clin Obstet Gynecol 6:742, 1963 Frangenheim H, Kleindienst W: Chronic pelvic disease of unknown origin. In Gynecologic Laparoscopy, Edited by JM Phillips, L Keith. New York, Stratton, 1974, p 52 Feste JR: Laser laparoscopy: a new modality. J Reprod Med 30:413, 1985
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74. Lichten EM, Bombard J: Surgical treatment of primary dysmenorrhea with laparoscopic uterine nerve ablation. J Reprod Med 32:37, 1987 75. Cutler SJ, Ederer F: Maximum utilization of the life table method in analyzing survival. J Chronic Dis 8:699, 1958 76. Cramer DW, Walker AM, Schiff I: Statistical methods in evaluating the outcome of infertility therapy. Fertil Steril 32:80,1979 77. Guzick DS, Rock JA: Estimation of a model of cumulative pregnancy following infertility therapy. Am J Obstet Gynecol 140:573, 1981 78. Marquardt DW: An algorithm for least-squares estimation of nonlinear parameters. J Soc Ind Appl Math 11:431, 1963 79. Olive DL: Analysis of clinical fertility trials: a methodologic review. Fertil Steril45:157, 1986 80. Olive DL, Haney AF: Endometriosis-associated infertility: a critical review of therapeutic approaches. Obstet Gynecol Surv 41:538, 1986 81. Davis GD, Brooks RA: Excision of pelvic endometriosis with the carbon dioxide laser laparoscope. Obstet Gynecol 72: 816, 1988 82. Eward RD: Cauterization of stages I and II endometriosis and the resulting pregnancy rate. In Endoscopy in Gynecology: the Proceedings of the Third International Congress on Gynecologic Endoscopy, Edited by JM Phillips. Downey, American Association of Gynecologic Laparoscopists, 1978, p 276 83. Mitchell GW, Farber M: Medical versus surgical management of endometriosis. In Controversy in Obstetrics and Gynecology, Vol 2, Edited by DE Reid and CO Christian. Philadelphia, W.B. Saunders, 1974, p 631 84. Hasson HM: Electrocoagulation of pelvic endometriotic lesions with laparoscopic control. Am J Obstet Gynecol 135: 115,1979 85. Sulewski JM, Curcio FD, Bronitsky C, Stenger VG: The treatment of endometriosis at laparoscopy for infertility. Am J Obstet GynecoI138:128, 1980 86. Daniell JF, Pittaway DE: Use of the CO 2 laser in laparoscopic surgery: initial experience with the second puncture technique. Infertil 5:15, 1982 87. Acosta AA, Buttram VC, Jr, Besch PK, Malinak LR, Franklin RR, Vanderheyden JD: A proposed classification of pelvic endometriosis. Obstet Gynecol 42:19, 1973 88. Seiler JC, Gidwani G, Ballard L: Laparoscopic cauterization of endometriosis for fertility: a controlled study. Fertil Steril 46:1098, 1986 89. Nowroozi K, Chase JS, Check JH, Wu CH: The importance of laparoscopic coagulation of mild endometriosis in infertile women. Int J Fertil 32:442, 1987 90. Murphy AA, Schlaff WD, Hassiakos D, Durmusoglu F, Damewood MD, Rock JA: Laparoscopic cautery in the treatment of endometriosis-related infertility. Fertil Steril. In press 91. Adamson GD, Lu J, Subak LL: Laparoscopic CO2 laser vaporization of endometriosis compared with traditional treatments. Fertil Steril 50:704, 1988 92. Goldfarb HA: The use of the carbon dioxide laser during laparoscopic surgery. N J Med 85:27,1988 93. Baggish MS, Sze E, Badawy S, Choe J: Carbon dioxide laser laparoscopy by means of a 3.0-mm diameter rigid wave guide. Fertil Steril 50:419, 1988 94. Mage G, Canis M, Pouly JL, Manhes H, Wattiez A, Bruhat MA: CO2 laser laparoscopy: a ten-year experience. Eur J Obstet Gynecol Reprod Bioi 28:120, 1988
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95. Paulsen JD, Asmar P: The use of CO 2 laser laparoscopy for treating endometriosis. Int J Fertil 32:237, 1987 96. Davis G D: Management of endometriosis and its associated adhesions with the CO 2 laser laparoscope. Obstet Gynecol 68:422, 1986 97. Nezhat C, Crowgey SR, Garrison CP: Surgical treatment of endometriosis via laser laparoscopy. Fertil Steril45:778, 1986 98. Daniell JF, Herbert CM: A new second-puncture probe for CO 2 laser laparoscopy. J Reprod Med 30:89, 1985 99. Tadir Y, Kaplan I, Zuckerman Z, Edelstein T, Ovadia J: New instrumentation and technique for laparoscopic carbon dioxide laser operations: a preliminary report. Obstet Gynecol 63:582, 1984 100. Kelly RW, Roberts DK: CO 2 laser laparoscopy. A potential alternative to danazol in the treatment of stage I and II endometriosis. J Reprod Med 28:638, 1983 101. Daniell JF, Brown DH: Carbon dioxide laser laparoscopy: initial experience in experimental animals and humans. Obstet Gynecol 59:761, 1982 102. Martin DC: CO 2 laser laparoscopy for the treatment of endometriosis associated with infertility. J Reprod Med 30: 409, 1985 103. Daniell JF, Miller W, Tosh R: Initial evaluation of the use of the potassium-titanyl-phosphate (KTP /532) laser in gynecologic laparoscopy. Fertil Steril 46:373, 1986 104. Lomano JM: Photocoagulation of early pelvic endometriosis with the Nd:YAG laser through the laparoscope. J Reprod Med 30:77, 1985 105. Keye WR, Dixon J: Photocoagulation of endometriosis by the argon laser through the laparoscope. Obstet Gynecol 62: 383, 1983 106. Chong AP: Danazol versus carbon dioxide laser plus postoperative danazol. Treatment of infertility due to mild pelvic endometriosis. Lasers Surg Med 5:571, 1985 107. Martin DC: CO 2 laser laparoscopy for endometriosis associated with infertility. J Reprod Med 31:1089, 1986 108. Olive DL, Martin DC: Treatment of endometriosis-associated infertility with CO 2 laser laparoscopy: the use of oneand two-parameter exponential models. Fertil Steril48:18, 1987
109. Donnez J: CO 2 laser laparoscopy in infertile women with endometriosis and women with adnexal adhesions. Fertil Steril 48:390, 1987 1l0. Gast MJ, Tobler R, Strickler RC, Odem R, Pineda J: Laser vaporization of endometriosis in an infertile population: the role of complicating factors. Fertil Steril 49:32, 1988 Ill. Fayez JA, Collazo LM, Vernon C: Comparison of different modalities of treatment for minimal and mild endometriosis. Am J Obstet GynecoI159:927, 1988 ll2. Nezhat C, Crowgey S, Nezhat F: Videolaseroscopy for the treatment of endometriosis associated with infertility. Fertil Steril 51:237, 1989 113. Classification of endometriosis. The American Fertility Society. Fertil Steril 32:633, 1979 ll4. Bruhat MA, Mage G, Pouly JL: Use of the CO 2 laser in laparoscopy. In Laser Surgery: Proceedings of the 3rd International Symposium on Laser Surgery, Edited by I Kaplan, PW Ascher. Tel Aviv, OT-PAZ Press, 1979, p 274 ll5. Tadir Y, Ovadia J, Zuckerman Z, Kaplan I: Laparoscopic application of the CO 2 laser. In Proceedings of the Fourth Congress of the International Society for Laser Surgery. Edited by K Atsumi, N Nimsakul. Tokyo, Japanese Society for Laser Medicine, 1981, p 25 ll6. Nezhat C, Crowgey SR, Garrison CP: Surgical treatment of endometriosis via laser laparoscopy and videolaseroscopy. Contrib Gynecol Obstet 16:303, 1987 ll7. Buttram VC, Jr, Reiter RC, Ward S: Treatment of endometriosis with danazol: report of a 6-year study. Fertil Steril 43:353, 1985 118. Wheeler JM, Malinak LR: Postoperative danazol therapy in infertility patients with severe endometriosis. Fertil Steril 36:460, 1981 ll9. Hulka JF: Biophysics and physiology. In Textbook of Laparoscopy. Orlando, Grune and Stratton, Inc., 1985, p 7 120. Dougherty TJ: Photodynamic therapy. In Endoscopic Laser Surgery Handbook, Edited by SM Shapshay. New York, Marcel Dekker Inc., 1987, p 424 121. Manyak MJ, Nelson LM, Solomon D, Russo A, Thomas GF, Stillman RJ: Photodynamic therapy of rabbit endometrial implants: a model treatment of endometriosis. Fertil Steril 52:140, 1989
Received September 4, 1990. * Reprint requests: John A. Rock, M.D., The Johns Hopkins Hospital, Department of Gynecology and Obstetrics, Division of Reproductive Endocrinology, Houck 247, 600 North Wolfe Street, Baltimore, Maryland 21205.
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Fertility and Sterility
Modern trends Edward E. Wallach} M.D., FERTILITY AND STERILITY
Asei(l~i.ate ~.
Printed on acid-free paper in U.S.A.
Copyright" 1991 The American Fertility Society
The role of laparoscopy in the treatment of endometriosis
AndrewS. Cook, M.D. John A. Rock, M.D.* The Johns Hopkins Hospital, Department of Gynecology and Obstetrics, Division of Reproductive Endocrinology, Baltimore, Maryland
The primary goal in the surgical treatment of endometriosis is complete removal of both typical and atypical endometrial implants. 1 The typical "powder burn" lesion has been traditionally taught as being the standard appearance of an endometriotic lesion. Although the pigmented implant is the most easily identified type of lesion, it is becoming apparent that these implants contain inactive glands and stoma embedded with hemosiderin. In contrast, the atypical or nonpigmented lesion contains active endometriotic glands and stroma that may result in progression of disease and symptomatology. The depth of the implant is also related to disease activity, with deep endometriosis containing very active disease. 2 It is believed, but not proven, that excision or ablation of the endometrial implants will increase the fertility potential of the patient. 3 The advent of operative laparoscopy represents an advancement in the treatment of endometriosis.4-10 The advantages of laparoscopic treatment include a decrease in patient morbidity, reduction in length of hospital stay and costs, as well as the opportunity to treat at the time of diagnosis, and potentially a reduction in postoperative adhesion formation with an increased pregnancy rate (PR). 11 Minimal postoperative adhesion formation is noted clinically with laparoscopic surgeryP- 14 The results of controlled animal studies have varied with some but not all studies demonstrating a significantly lower postoperative adhesion formation after operative laparoscopy in comparison with laparotomy.15·16 It has been demonstrated at second-look laparoscopy that 58% of patients without previous adhesions will experience adhesion formation, and 92% of patients who had adhesions lysed at laparotomy will have persistent or reformation of adhesions.17 Surgical treatment of endometriosis falls into two basic categories: (1) ablation and/or resection of enVol. 55, No.4, April1991
dometriotic implants in cases with normal pelvic anatomy and (2) ablation and/or resection of endometriotic implants and correction of abnormal pelvic anatomy. Resection or ablation of endometrial implants is best accomplished surgically through the laparoscope rather than through the open abdomen. Debate arises, however, over potential differences in PRs depending on which endoscopic method is used to ablate (electrocautery, endocoagulation, or laser) or resect the endometrial implants. The extent of anatomical distortion that can or should be treated through the laparoscope rather than at laparotomy is the subject of considerable controversy. Some surgeons feel that certain limitations encountered with laparoscopic surgery prevent the use of proper surgical technique and therefore acceptable results. There are several technical limitations unique to laparoscopic surgery. These include loss of depth perception, inability to directly palpate the tissue, limitation of the instrumentation including the number and orientation of the instruments, and the increased distance between the surgeon's hand and the operating field. The remote position of the operator's hands and lack of hand support can make some fine and exact movements difficult. The extent of endometriosis that can be treated laparoscopically is related to the restricted access of the surgical field. Many of the limitations encountered during laparoscopic surgery can be overcome by the skill of the surgeon; however, certain difficult microsurgical dissections cannot be adequately performed laparoscopically. In comparison with laparoscopy, laparotomy will provide (1) better identification of tissue planes through enhanced depth perception and direct palpation of tissue and (2) improved access to the tissue with greater precision of movements, increased flexibility in orientation of instrumentation, and a superior variety of available instrumenCook and Rock
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tation. Therefore the decision to perform the procedure through the laparoscope or through the open abdomen is not dependent on the stage of endometriosis encountered as determined by The American Fertility Society (AFS) classification system. Rather, the failure to perform the procedure endoscopically results from (1) the inability to safely dissect between tissue planes and (2) the need for improved access to the tissue for atraumatic manipulation and strict adherence to the principles of good surgical technique. Specific procedures involved in the treatment of endometriosis that can be treated laparoscopically include ablation of peritoneal endometriosis, adhesiolysis, ovarian cystectomy, oophorectomy, and salpingectomy. Procedures for the treatment of endometriosis that require laparotomy include bowel resection, complete presacral neurectomy, and excision or ablation of deep endometriosis that cannot safely be isolated from vital structures. Some large endometriomas will need to be treated at laparotomy and a wide range of opinion exists regarding the role of laparoscopic tubal reconstruction. The ultimate choice of modality must depend on the proven effectiveness of therapy. DIAGNOSIS OF ENDOMETRIOSIS
Awareness of the wide range of visual appearance of endometriosis is necessary to make an accurate diagnosis so that proper treatment can be instituted and the surgeon may avoid incorrectly labeling a patient as having unexplained infertility or pain. It has been estimated that the diagnosis of endometriosis has been missed in 7% of patients, and the extent of the disease has been underestimated in as many as 50% of patients. 1 Conversely, it has been shown that many other lesions have an appearance similar to the typical endometrial lesion. These lesions include old suture, ovarian cancer, residual carbon deposits from previous surgery, and hemangiomas. 18,i9 The diagnosis of endometriosis has traditionally been made by visual inspection with identification of the bluish or typical powder burn lesion. It has become evident, over the last several years, that the appearance of endometriosis can be quite varied in its presentation. Several recent articles have described atypical and nonpigmented forms of endometriosis. 1,2,19 Martin et al. l have described as many as 20 different morphological appearances of endometriosis including scarred lesions, red lesions, vesicular lesions, peritoneal windows, yellow-brown patches, and adhesions. The loss of depth perception 664
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with the uniocular laparoscope makes diagnosis of some nonpigmented lesions difficult. Redwine 20 has even suggested painting the peritoneum with blood to enhance the diagnosis of subtle lesions. The atypical endometrial lesions may represent early active endometriosis that with time will progress to pigmented lesions. 19 Several studies have shown a 40% to 45% association of endometriosis with peritoneal defects or pockets. 21 ,22 An interesting study by Cornillie et a1. 2 demonstrates a correlation between the activity and the depth of the endometrial implant. Cellular activity was noted in 58% of the superficial implants «1 mm) and 68% of deep implants (?c5 mm). Yet only 25% of intermediate implants (2 to 4 mm) were noted to have cellular activity. The authors postulate that superficial implants represent the initial stage of proliferation of retrograde menstruation. As proliferation of the lesion progresses to an intermediate depth, many of the implants burn out under the influence of the high progesterone in the peritoneal fluid. Implants that survive and invade deeply (>5 mm) are primarily under the influence of circulating steroids and become very active. The assessment of the depth of the lesion at laparoscopy correlated well with the histologic measurements. Magnification with "near-contact laparoscopy" has been proposed to increase the sensitivity of visual diagnosis of endometriosis. 23 Increased magnification may allow identification of subtle peritoneal surface irregularities and excisional biopsy. Magnification up to 8X, depending on the working distance, can be obtained with the laparoscope (Table 1). Several studies using scanning electron microscopy, however, have documented endometriosis in normal appearing peritoneum. 25 - 28 A recent study demonstrated endometriosis (313 JLm ± 185 JLm) by light microscopy present in normal appearing
Table 1 Magnification Rates Obtained With Operating Laparoscopes· Magnification rate Operating laparoscope working distance
Wolf
Olympus
mm
3 5 10
3.19
15 20
1.71
30 50
1.7 1.2
0.73
0.7
8.2 5.7 3.2 2.2
• From Murphy et a1. 2' (Reproduced with permission of the publisher, The American Fertility Society).
Fertility and Sterility
endometrium in 13% of patients with endometriosis and 6% of infertility patients undergoing laparoscopy without endometriosis. 29 Recurrence rates of 13.5% and 40% at 3 and 5 years, respectively, have been documented after surgical treatment. 30 This recurrence of symptoms may represent persistence of microscopic «200 JLm) or retroperitoneal disease. Surgical treatment of endometriosis is therefore most likely cytoreductive rather than ablative. Identification of deep ovarian endometriomas is important for correct staging. A recent study demonstrated the presence of small deep ovarian endometriomas in 48% of patients who had slightly enlarged ovaries (maximum diameter 3.5 to 5 cm) but were otherwise normal in their appearance. 31 Using the Revised American Fertility Society classification system32 (R-AFS), 32% of the patients in this study had stage I endometriosis, 36% stage II endometriosis, none with stage III or IV, and 32% of the patients had no endometriosis. The diagnosis and determination of the diameter of occult ovarian endometriomas was accomplished with ovarian puncture using a 16-gauge needle. After restaging, 8% of patients had stage I endometriosis, 16% stage II endometriosis, 64% stage III endometriosis, and 12% stage IV endometriosis. The authors found preoperative sonographic evaluation to be useful in screening for small ovarian endometriomas.
TREATMENT OF ENDOMETRIOTIC IMPLANTS
Several basic techniques are used in the surgical ablation of endometriosis. Endometrial implants can be resected, coagulated, or vaporized. IS Coagulation can be achieved by using the unipolar or bipolar electrocautery, the endocoagulator, or the various surgical lasers. A complete working knowledge ofthe biophysical principles of the various modalities (electrocautery, endocoagulation, surgical lasers) is necessary before their clinical use. Many patients are under the impression that the surgical laser offers a new and improved form of treatment with a marked increase in the success rate over other modalities, and some members of the medical profession have contributed to this impression. Much of this misperception is based on the lack of understanding of the basic physical principles of various available modalities, including surgical lasers and the laser-tissue interaction. An understanding of these principles will allow the surgeon to both realize the limitations and utilize the advantages of a given treatment modality. Vol. 55, No.4, Aprii1991
All of the above mentioned treatment modalities work through the generation of thermal energy. Blood vessels and lymphatic ducts act as convective systems to dissipate excessive heat. When energy accumulates faster in the tissue than it can be dissipated by these systems, the temperature of the tissue will rise. Coagulation occurs at temperatures < 100°C, whereas vaporization and cutting occur at temperatures> 100°C. Coagulation results in denaturation of macromolecules, primarily proteins, with breakage of the bonds that stabilize the conformation of the molecule. Denaturation of enzymes occurs in the range of 40°C to 65°C and denaturation of deoxyribonucleic acid occurs above 80°C. Conversion of intracellular and extracellular water to vapor, with a 1,670-fold increase in volume, occurs at temperatures> 100°C. The rapid expansion of vapor results in transformation of thermal energy to mechanical energy. The mechanical energy performs work on the remaining solid tissue, tearing the cellular membranes and displacing cellular components, causing tissue separation. Biophysical Principles of Electrocautery
The standard household current is an alternating current with a frequency of 60 cycles/so Muscles and nerves respond to frequencies below 10,000 Hz. Electrocautery generators increase the frequency of the electrical current from 60 Hz to frequencies between 300,000 and 4 million Hz. The first surgical electrocautery generator was designed by William Bovie and is the basis for the term Bovie cautery.33 Electrocautery generators have two basic modes, cutting and coagulation. The cutting current is a continuous current, whereas the coagulating current is a current that is interrupted with periods of electrical inactivity (Fig. 1). The cutting current results in a rapid increase in temperature with vaporization, whereas the coagulating current allows for a less intense rise in the temperature, resulting in coagulation. Electrocauterization requires a closed circuit to work. Unipolar cautery incorporates the patient's entire body into the circuit. High-frequency electrical current flows from the generator through the laparoscopic electroinstrument, through the patient, and then exits through the grounding pad and returns to the generator. The potential disadvantages of unipolar cautery are related to (1) the unpredictable route of the electrical current and its potential thermal damage and necrosis to vital structures (e.g., bowel) and (2) the relatively large area of thermal damage and necrosis that is not visible at the time of surgery. Peritoneal damage may result in inCook and Rock
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A
element at the tip of the Teflon-coated probe generating temperatures of up to 120°C. The major suggested advantages of endocoagulation are (1) limitation of the area of necrosis and (2) elimination of the high-frequency electrical current in the abdominal cavity, thus eliminating the potential for electrical burns. Studies have shown that coagulation only occurs to a depth of 1 to 2 mm and thus is not effective in ablation of deep endometrial implants. 36 The primary role of endocoagulation is ablation of superficial endometrial implants and coagulation of intact vessels or minor oozing. The endocoagulator does not work well in obtaining hemostasis of actively bleeding vessels, which dissipate the heat generated by this relatively low energy source.
B
Biophysical Principles of Lasers Figure 1 Electrocoagulation currents. (A), "Cutting current." (B), "Coagulating current."
creased adhesion formation, and unrecognized bowel injuries have resulted in death. 34 The risk of the above complications occurring is related to several factors. The newer generators are much safer than the original spark gap generators, and the skill of the surgeon is paramount in the safe use of intraperitoneal electrocautery. The extent of tissue penetration is related to the duration of application, power and type of current, and the size of the electrode. Thus, the application of monopolar fine needle electrocautery of short duration with blended current may be safely used in adhesiolysis with minimal damage to surrounding tissue. Endoscopic use of the bipolar electrocautery is usually safer than unipolar cautery. High-frequency current from the generator passes from one paddle of the bipolar instrument, through the intervening tissue, to the other paddle and back up the laparoscope to the generator, completing the circuit. As a result, essentially, the only tissue exposed to electrical current, and thus cauterization, is that between the paddles of the bipolar instrument. The area of tissue necrosis is more controlled and limited than that seen with unipolar cautery, provided lateral thermal spread is limited by electrical current applications of short duration. Biophysical Principles of Endocoagulation
Endocoagulation, developed by Semm, utilizes direct application of heat to the tissue for coagulation. 35 Electrical current passes through a resistance 666
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Laparoscopic treatment of endometriosis
The laser (an acronym for light amplification by stimulated emission of radiation) is a useful instrument in the armamentarium of surgical tools. Four basic phenomena may occur in tissue when it is struck by laser light. These include (1) absorption by the tissue; (2) scattering within the tissue; (3) reflection from the surface, which results in decreased efficiency of the laser; and (4) transmission through the tissue. The power of the laser beam is attenuated as a result of both absorption (primarily by cellular water) and scattering as it moves through the depth of the tissue. The absorption oflaser light in a given tissue results in an increase in the kinetic and vibrational energy within the atoms and the molecules, which is manifested as thermal energy. Thermal energy is the means by which the surgical laser performs all of its functions. Scattering of the laser beam results in a change in direction of a portion of the laser light without an overall loss of energy. There is a decrease in the power of the initial direction of the laser beam and a measurable power density in directions not parallel with the axis of the laser beam. Scattering of the laser light results in a lateral spread ofthe thermal effect on the tissue. The wavelength of a laser determines the absorption to scattering ratio, which is primarily responsible for the individual characteristic of the various surgicallasers (Table 2). Lasers with a long wavelength (>3,000 nm) have a low scatter to absorption ratio and are thus effective for tissue vaporization but poor for coagulation. Lasers with a short wavelength (700 to 1,400 nm) have good coagulation abilities but are poor vaporizers. The scatter to absorption ratio of visible lasers (e.g., potassium-titanyl-phosphate [KTP] and argon lasers) is highly dependent on the color of the target Fertility and Sterility
Table 2
Biophysical Properties of the Different Lasers a Maximum power output
Wavelength
Laser
CO 2 Argon
Extinction length b
Fiber compatible
Primary effect
Secondary effect
~m
w
mm
10.6 0.488 to 0.514
500 20
0.05 0.2
No Yes
Vaporization Coagulation
1.06
100
0.8-2.0
Yes
Coagulation (vaporization at high power)
Nd:YAG
None Delayed thermal damage Significant backscatter
a From Vancaillie and Schenken. 37 (Reproduced with permission of the publisher).
b Extinction length is the depth of tissue that absorbs 90% of energy at standardized power and exposure time. An index of the laser's ability to penetrate tissue.
tissue. These lasers have fairly good coagulating ability but are poor vaporizers. The ideal laser would have a variable wavelength that could be changed and thus the degree of coagulation or vaporization selected. The parameters of the laser that effect the energy delivered to the tissue include power, duration, and the wavelength of the electromagnetic radiation. The power of the laser beam, which is proportional to the number of photons per second, is known as watts. The power density, which is the number of watts per cm 2 , is more reflective of the energy delivered to a unit area. For any given power (watt), the power density is directly proportional to the spot size (Table 3). Thus, the amount of energy to which a given tissue is exposed is dependent on both the power setting of the laser and the spot size of the beam. Duration of exposure affects both the depth of penetration and the relative degree of vaporization or coagulation necrosis. The wavelength of the electromagnetic radiation emitted by a laser is unique to the active medium ofthe laser (e.g., carbon dioxide [C0 2 ] or argon).
but poor for the purpose of coagulation. As demonstrated in Figure 2, the power density of the laser beam is in a Gaussian distribution with a higher power density in the middle portion of the beam and decreasing levels toward the periphery.39 The zone of thermal necrosis with CO 2 laser is minimal initially and is further minimized by the progressive elongation of the bore contour secondary to the relative increased central bore speed (Fig. 2). The zone of thermal necrosis in the superpulse mode is approximately one third of the zone of thermal necrosis in the continuous setting. This setting is therefore used in situations in which maximal tissue vaporization (cutting or ablation) and minimal tissue necrosis or coagulation is desired. The clinical relevance of the contour of the bore hole created by the CO 2 laser is demonstrated by its excellent vaporization and poor coagulation ability. As a CO 2 bore hole reaches and begins to penetrate the wall of a blood vessel, vaporization creates a small hole yet only minimal coagulation occurs. With the creation of a hole in the wall of a blood vessel, there is release of plasma. The plasma then acts to dissipate the heat and prevents further vaporization as well as preventing coagulation of the blood vessel and thus hemostasis.
CO2 Laser
The CO 2 laser has a wavelength of 10,600 nm and thus is excellent for ablation and cutting of tissue Table 3
Power Density Charta Power
Spot size
2
5
10
15
20
25
30
40
50
5,497 1,374 611 220 98 55 35 24
13,743 3,436 1,527 550 244 137 88 61
27,485 6,871 3,054 1,099 489 275 176 122
41,228 10,307 4,581 1,649 733 412 264 183
54,970 13,743 6,108 2,199 977 550 352 244
68,713 17,178 7,635 2,749 1,222 687 440 305
82,455 20,614 9,162 3,298 1,466 825 528 366
109,940 27,485 12,216 4,398 1,954 1,099 704 489
137,425 34,356 15,269 5,497 2,443 1,374 880 611
mm
0.2 0.4 0.6 1.0 1.5 2.0 2.5 3.0
a Power density is W /cm2 • From Fuller TA.38 (Reproduced with permission of the publisher). Vol. 55, No.4, April 1991
Cook and Rock Laparoscopic treatment of endometriosis
667
sure, and automatically adjusts the flow rate, thus maintaining an adequate pneumoperitoneum. Neodymium Yttrium-Aluminum-Garnet (Nd:YAG) Laser
Figure 2 Cross section of CO 2 laser bore hole with elongation of vaporization with time (t). (From Fisher. 3• Reproduced with permission of the publisher).
The primary disadvantages of the CO 2 laser are its poor coagulation potential, its need for use of an articulating arm system, and its relatively high degree of smoke production. The potential for modification of the CO 2 laser to coagulate tissue is limited because of the wavelength characteristic. When in alignment, the articulating arm system works quite well. However, because of the need for a multiple mirror system, maladjustment of anyone of these mirrors or fatigue of any portion of the articulating arm will result in malalignment of the laser beam with movement of the articulating system. The waveguide system minimizes malalignment problems encountered with the articulation system. 40 Fiberoptic delivery systems are currently under development for the CO 2 laser but are not available clinically at this time. Smoke production, along with carbonization, is a result of burning of the solid residues that are expelled upwardly from the laser bore. This results in significant smoke production along with carbonization. There are no data currently available on potential side effects of the carbonization, therefore, the pelvis should be lavaged to remove as much of the residual carbon particles as possible. The smoke can be removed with a smoke evacuator and high-flow delivery systems. The stateof-the-art insufflator delivers CO 2 gas into the peritoneal cavity at a maximum rate of 6 Ljmin, simultaneously monitors the intra-abdominal pres668
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Laparoscopic treatment of endometriosis
The Nd:YAG laser has a wavelength of 1,064 nm, which results in properties of good coagulation and poor vaporization. The high degree of scatter of the Nd:YAG beam within tissue results in lateral dispersement of the thermal effect. In contrast to the CO 2 laser, the diameter of the affected area is much greater than that of the laser beam (Fig. 3). When coagulation of the tissue has occurred, there is a dramatic increase in the scattering coefficient, and the affected volume spreads laterally with minimal increase in the depth of penetration. The degree of lateral dispersement of the thermal energy also is time dependent. The Nd:YAG laser beam is delivered by a quartz optical fiber. The waves of the laser emerge from the tip with a divergence of 5 to 15 degrees, thus there is a marked decrease in the power density as the distance from the target tissue increases. As a result, the tip of the fiber must be placed in close proximity to the tissue to afford effective coagulation and vaporization. In 1984, the sapphire tip was introduced for use with the Nd:YAG laser.39 A variety of contours that had the effect of either focusing or defocusing the laser beam for the desired effect were introduced. 41 •42 A focusing or convergence of the laser beam results
LLr-A..----
QUlrtz Fiber
to-Witt Glussi.n BUJI of Md-YAG lner
Figure 3 Cross section of Nd:YAG laser bore hole with divergence of beam from quartz fiber. (From Fisher.39 Reproduced with permission of the publisher).
Fertility and Sterility
in an increase in cutting and vaporizing ability. In addition, the sapphire tip was designed to be used in contact with the tissue, which not only helped reduce the scattering of the beam but also eliminated the 50% reflection at the surface of the tissue and thus greatly enhanced the efficiency of this laser.43 The primary drawbacks of the sapphire tip are the disposable nature (the tip melts with each use and thus must be discarded) and its expense. A microcontact probe has recently been developed for use with the Nd:YAG laser. This works in principle much like the sapphire tip. It is used in contact with the target tissue and is disposable; however, the cost of fiber is approximately one third that of the sapphire tip. Potassium-Titanyl-Phosphate Laser
The active medium in the KTP laser is the same as an Nd:YAG laser. The wavelength of the KTP laser is 532 nm (one half of the wavelength of the Nd:YAG laser), which is a result of the beam passing through a KTP crystal. The KTP laser has a wavelength similar to the argon laser and thus has similar characteristics. The beam, delivered through a quartz fiber, has a primary effect of vaporization when the fiber is in contact with the tissue. As the distance between the fiber and the tissue increases, the primary effect becomes coagulation. The main disadvantage of the KTP laser is the need for the use of a filter because irreparable retinal damage can occur through an unprotected laparoscope via back scatter. Argon Laser
The argon laser has a wavelength of 514 nm and thus the scatter to absorption ratio is somewhat dependent on the color of the target tissue. Treatment of endometriosis with the argon laser is most efficient in coagulation or vaporization of pigmented lesions. 44 Recent studies have, however, shown that a significant percentage of endometrial lesions are nonpigmented. 1,19,45 Another potential clinical use of the argon laser would be in excitation of hematoporphyrin in photodynamic therapy. In summary, the goal in the treatment of superficial endometriosis is selective ablation of endometrial implants while simultaneously preservin~ the surrounding healthy tissue. The decision to mechanically excise (with the knife or scissors) or to use electrocauterization, endocoagulation, or one of the currently available surgical lasers should be based on the clinical situation and the operator's skill in the use of these instruments. There is no Vol. 55, No.4, April 1991
evidence that anyone of these treatment modalities is more successful than another in affecting the end result (e.g., pregnancy or relief of pain). The selection of modality and surgical technique, therefore, depend on the skill of the operator and the location and nature of the lesion. TREATMENT OF ADVANCED ENDOMETRIOSIS
Treatment of advanced endometriosis includes ablation of deep or retroperitoneal endometriosis and correction of abnormal pelvic anatomy, including adhesiolysis, ovarian cystectomy, oophorectomy, salpingectomy, and tubal reconstruction. In the majority of cases, these conditions are best treated by operative laparoscopy. Surgical treatment at laparotomy is required in cases in which technical limitations preclude operative laparoscopy. Adhesiolysis
The range of adhesions encountered in patients with endometriosis varies from transparent, avascular adhesions to extremely dense, cohesive adhesions that completely obliterate the tissue planes. The basic surgical maxim, to operate with minimal tissue trauma, applies to laparoscopic lysis of adhesions. Forceful blunt dissection of adhesions, which is successful but leaves a bloody, traumatized field, invariably results in reformation of adhesions and is thus unacceptable. Laparoscopic lysis of adhesions must be a meticulous delicate process with minimal trauma to the tissue and complete hemostasis. Transparent, avascular adhesions, which approximate two structures, may be lysed by delicate pressure, with scissors or aquadissection. When adhesions are dense and cohesive, a combination of blunt and sharp dissection is used. As the adhesions become more vascular, bleeding will be encountered and hemostasis should be accomplished using one of the coagulation methods described above. In the presence of vascular adhesions in which there is a space between the two structures, vessels encountered along the transection line should be coagulated before division. Dense adhesions may be lysed sharply or with a surgical laser while on "the stretch."46 Use of the surgical laser for adhesiolysis offers the advantages of (1) simultaneous coagulation of small vessels/capillaries during lysis of adhesions (Nd:YAG laser> CO 2 laser) and (2) improved visualization of the surgical field (scissors used through the operating channel of the laparoscope partially occlude the operating field).47 Cook and Rock
Laparoscopic treatment of endometriosis
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Technical difficulties arise in limitation of the approach to the surgical field and inability to palpate the tissue. If necessary, one can use the second or third puncture site to insert a 5-mm laparoscope to gain a different field of view to better identify the tissue planes. Vital structures that may be involved in the adhesive complex (e.g., bowel, ureter, or vessels) must be clearly identified before dissection. If this is not possible, laparotomy is indicated. Secondlook laparoscopy may playa vital role in minimizing . a dh' 4849 postoperative eSlOns.' Resection of an Ovarian Endometrioma
Resection of endometriomas < 3 cm frequently occurs at laparoscopy. Endoscopic resection oflarger endometriomas is feasible. Factors that limit the size of endometriomas that can be resected are primarily related to the technical limitations experienced in endoscopic surgery. Endoscopic resection of endometriomas can be performed using two basic methods. The first method involves exposure, aspiration of contents, and removal of the cyst capsule. The second method requires dissection of the intact cyst with subsequent drainage and removal through the laparoscope. Simple drainage of the endometrioma is not adequate; the cyst wall must be excised or ablated. 50.51 Some authors feel that all periovarian adhesions must be removed before resection of the endometrioma. 52 If the adhesions do not limit access or visualization of the surgical field, they may actually make dissection of the endometrioma easier by holding the ovary in place and thus allow the surgeon to use the instruments for dissection rather than for retraction. Therefore, in select cases the periovarian adhesions may be lysed after resection of an endometrioma. Using the first method, the ovarian capsule overlying the endometrioma is incised. The cyst is drained, the ovarian capsule is stabilized with atraumatic forceps, and the cyst wall is grasped with forceps and peeled out with a corkscrew maneuver (Fig. 4). Occasionally, the cyst wall is friable and difficult to remove. If this situation is encountered, blunt and sharp dissection of the cyst from the ovarian capsule may be needed. Vessels encountered during removal of the cyst should be coagulated with the bipolar cautery before transection. If the cyst cannot be removed completely, remaining fragments of the cyst wall should be vaporized with the laser or fulgurated with electrocautery.51 Alternatively, the cyst can be shelled out intact using traction with sharp and blunt dissection while avoiding traumatizing the ovarian cortex. When the 670
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Laparoscapic treatment af endometriosis
Figure 4 Laparoscopic dissection of a cyst wall from the ovarian cortex, (From Vancaillie and Schenken. 37 Reproduced with permission of the publisher).
cyst is removed from the ovary, it is drained and removed through the laparoscope. This latter technique allows for better visualization of the tissue plane and assures complete removal of the cyst wall. Through the open abdomen, after an ovarian cystectomy, the edges of the ovarian cortex should be reapproximated using microsurgical techniques to close the defect and thus prevent adhesion formation to the raw surface. Sutures should not penetrate the ovarian capsule, thus a subcortical closure is recommended. A recent study by Brumsted et aI.,53 using a rabbit model suggests these techniques may be unnecessary. The authors found that if the ovarian cortex was left open, after a wedge resection, adhesion formation was less (but not significant) than if the cortex was reapproximated using microsurgical techniques. Comparison of surgical techniques used to perform the wedge resection (cold knife versus Nd:YAG laser) failed to show a difference in postoperative adhesion formation. These data suggest that endometriomas may be removed endoscopically and the defect left open, provided that the cyst wall can be completely removed with atraumatic techniques. However, because there is no supportive evidence in the human, this issue should be addressed through investigations with randomized controlled studies. Laparoscopic Salpingectomy
If the fallopian tube has been irreparably damaged in a patient undergoing laparoscopic treatment of Fertility and Sterility
endometriosis, the decision may be made to perform a salpingectomy. One of two techniques may be used to perform a laparoscopic salpingectomy. The fallopian tube should be adhesion-free before performing the salpingectomy. The fallopian tube may be doubly ligated with endoloop sutures and excised with the laparoscopic scissors. Alternatively, the fallopian tube and mesosalpinx may be serially electrocoagulated with the bipolar forceps and cut with the laparoscopic scissors. A combination of the above methods has also been applied successfully. Laparoscopic Oophorectomy
Occasionally, treatment of a patient for endometriosis will involve removal of one or both ovaries. Most commonly, this would apply to the patient who has chronic pelvic pain secondary to ovarian endometriosis and has completed her family. Rarely, the ovary is functionally destroyed and is removed to prevent further adhesion formation. The infundibulopelvic ligament may be ligated with three endoloop sutures and then transected. Alternatively, serial coagulation or clips using a laparoscopic stapling device may be used for hemostasis before cutting vascular pedicles. The ovary is then morcellated. Laparoscopic Tubal Reconstruction
Peritubal adhesions and tubal damage along the length of the fallopian tube may be encountered in patients with advanced endometriosis. Endometri0sis and sequelae of pelvic inflammatory disease may coexist and result in tubal occlusion. Tubal obstruction, however, rarely occurs solely as a result of involvement with endometriosis. If obstruction is present, it is often associated with extensive adhesion formation, ovarian, and peritoneal endometri0sis. Laparoscopic tubal reconstruction includes salpingo-ovariolysis, fimbrioplasty, and neosalpingostomy.54-58 The role oflaparoscopic neosalpingostomy is one of the most controversial areas of operative laparoscopy. The central issue to laparoscopic neosalpingostomy is comparative PRs with laparotomy.59-61 The overall reported PR after laparoscopic neosalpingostomy is approximately 27%; however, these studies either exclude patients with endometriosis or do not specify if endometriosis is a factor. 62- 65 There are few data regarding the extent to which laparoscopic neosalpingostomy alters fertility of patients with endometriosis-associated tubal obstruction. Treatment of Retroperitoneal and Deep Endometriosis
Deep (>5 mm) and very deep (>10 mm) endometrial implants represent a very active form of enVol. 55, No.4, April 1991
dometriosis. Estimation ofthe depth of endometrial implants at the time of laparoscopic resection correlate well with histologic measurements. 2The depth of penetration of endometrial implants roughly correlates with the percent of patients presenting with pelvic pain. Very deep implants have been demonstrated exclusively in patients with pain.2 Endometriosis infiltrates through the septa of loose connective tissue and is stopped by adipose tissue. This is probably the reason deep endometriosis is found in the posterior cul-de-sac and the uterosacralligaments but not in the ovarian fossa. 2 In addition to visualization, the diagnosis of retroperitoneal endometriosis is made by preoperative rectovaginal palpation and blunt probe palpation. 66 Laparoscopic treatment of retroperitoneal and deep endometriosis is often complicated by close proximity of vital structures (e.g., ureter, bladder, or vessels). The use of hydrodissection has recently been reported. 67 Hydrodissection may be used in conjunction with any surgical modality. A small hole is created in the peritoneum, and a sufficient amount of lactated Ringer's solution is injected retroperitoneally with the hydrodissection system. This technique provides two functions: (1) separation of the lesion from underlying structures and (2) buffer action to protect underlying structures from thermal damage from the surgical laser (the water disperses the thermal energy of the laser). Peritoneal endometriosis overlying a vital structure can be safely vaporized after hydrodissection. If the electrocautery is used, this technique reduces, but does not eliminate, the transmission of current. Endometriosis that superficially involves the muscularis of the bowel or bladder (but is not full thickness, as determined by preoperative cystoscopy and colonoscopy) may be ablated by laser vaporization. If retroperitoneal disease is present, the laser or laparoscopic scissors may be used to incise the peritoneum, the retroperitoneum may then be explored, and all implants ablated or excised. Peritoneal windows are usually associated with endometriosis, and thus the edges of the window should be opened and vaporized even if they appear grossly norma1. 21 ,22,68 This can be safely accomplished with a buffer of retroperitoneal water. If the lesions cannot be adequately isolated or completely ablated, laparotomy or adjunctive medical therapy should be considered. Retroperitoneal dissection may be facilitated by placing a bougie in the rectum and sponge forceps in the vagina. Traction in either direction may help open the rectovaginal and pararectal spaces. Care should be taken to develop the spaces and to identify Cook and Rock
Laparoscapic treatment of endometriosis
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the ureter before coagulation or vaporization of disease. These safeguards apply to surgery performed through the open abdomen or through the laparoscope. Laparoscopic Uterosacral Transection
Transection of the uterosacral ligaments for relief of dysmenorrhea was originally described by Ruggi and Crosser. 69 More recently, Doyle70 and Doyle and Des Rosiers 71 have discussed the use of paracervical uterine denervation for the relief of dysmenorrhea and pelvic pain. Frangenheim and Kleindienst 72 were the first to propose laparoscopic transection of the uterosacral ligaments, but they had no data to demonstrate efficacy of this treatment modality. Feste73 reported a series of patients who were treated by laparoscopic laser ablation of the uterosacralligaments for relief of dysmenorrhea. Seventy-one percent of the 42 patients treated with laser neurectomy had little or no dysmenorrhea 1 year after treatment. Lichten and Bombard74 utilized bipolar cautery and transection of the uterosacral ligaments in a double-blind study of21 patients (11 treatment, 10 control). Significant improvement or relief of symptoms was noted in 9 of 11 patients 3 months postoperatively and in 5 patients after 1 year. None of the patients in the control group experienced relief of dysmenorrhea. A significant difference (P < 0.02) was observed at both 3 and 12 months postoperatively. Relief of pain may also be related to the ablation of uterosacral endometriosis at the time of transection. Seventy-five percent of 80 patients with endometriosis undergoing laparoscopic ablation of the uterosacral ligaments with the KTP laser in an uncontrolled study reported improved symptoms at 6 months of follow-up.65 The efficacy of this procedure should be established through well-designed randomized clinical trials. SUCCESS IN THE TREATMENT OF ENDOMETRIOSIS
Successful treatment of endometriosis can be defined as either attainment of a viable pregnancy or alleviation of pain. The nature of endometriosis is such that a significant portion of patients treated for pain experience recurrence of symptoms. Success, therefore, is additionally defined as the length of time the patient is symptom free and the percentage of patients that experience recurrence. Determination of the success rates of the various treatment modalities for endometriosis is difficult for several reasons, including: (1) numerous classifications systems; (2) lack of randomized prospective trials; (3) common use ofthe crude PR; and (4) lack 672
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of controls. Numerous classification systems have been used over the years, with the most recent classification system adopted in 1985.32 Thus, comparison of a consistent group or subset of patients with various degrees of severity of endometriosis is difficult. To date, no comprehensive prospective randomized clinical trial has been performed. Indeed, such a trial would require randomization of patients with the various stages of endometriosis with each of the currently available treatment modalities (expectant management, medical treatment, surgical treatment). The vast majority of articles in the literature report the success rate based on the crude PRo The crude PR is the number of patients who attain pregnancy divided by the number of patients treated. Therefore, a study with a longer follow-up period will have a more successful outcome than a study with a shorter follow-up period. Retrospective studies with varying lengths of patient follow-up may reflect different success rates related solely to this factor. Several different statistical models are available to help compensate for this factor including life table analysis and monthly fecundity rate. 75-80 These statistical models must be instituted routinely in future publications if we are to truly gain an appreciation for the success of a particular treatment modality as compared with a previous form of treatment. It is presumed that the presence of endometriosis results in a reduction, but not an elimination, of the fertility potential of an individual. Therefore, evaluation of a treatment modality must judge treatment success against the baseline PR (a control group). The use of operative laparoscopy for the treatment of endometriosis may involve resection or ablation of the endometrial implants with electrocautery, endothermy, or various surgical lasers, and restoration of normal anatomy.8! The majority of published reports describing the use of laparoscopy for the treatment of endometriosis involves less severe forms of the disease (e.g., stage I and 11). Thus, much ofthe debate in the literature revolves around which laparoscopic method of ablation (electrocautery, endocoagulation, or laser) of superficial implants is most successful. More recently, operative laparoscopy has assumed a progressively larger role in the treatment of advanced cases of endometriosis with correction of abnormal pelvic anatomy.65 The debate then focuses on what extent of disease should be treated through the laparoscope rather than through the open abdomen. Laparoscopic Treatment Utilizing Electrocautery
Laparoscopic treatment of endometriosis to enhance fertility initially utilized electrocautery for coagulation of endometrial implants.82 The overall Fertility and Sterility
crude PR reported in the literature, using this treatment modality irrespective of the stage of endometriosis, is 52%. The crude PR for minimal, mild, and moderate endometriosis is 64%, 52% and 36%, respectively (Table 4). The crude PR for severe endometriosis is 50%; however, this is based on two small studies with four of eight patients becoming pregnant. 84 ,90 The first reported use of endoscopic treatment of endometriosis with electrocautery was by Eward in 1978.82 Overall, 24 of 43 patients in this study became pregnant. Only two of the studies in the literature on laparoscopic treatment of endometriosis with electrocautery used a control group (expectant management). In the first of these two studies, 28 patients with endometriosis documented at laparoscopy presented with complaints of infertility or pelvic pain. 84 Nineteen patients underwent fulguration of endometriosis with electrocautery (11 patients with pelvic pain and 8 with infertility), whereas the other 9 patients (5 with pain and 4 with infertility) did not receive electrocautery. In the treatment group, 6 of 8 patients became pregnant and 7 of 11 patients experienced complete relief of pain, whereas in the control group only 1 of 4 patients became pregnant and 1 of 5 patients with pain had relief. The number of patients in this study is too small to be statistically significant. The second study that used a control group was a prospective randomized study of patients with mild endometriosis by Nowroozi et al. 89 One hundred twenty-three patients underwent laparoscopy and were assigned to either the treatment group, in which the endometrial implants were coagulated using electrocautery, or the control group, in which the endometrial Table 4
implants were left intact. Forty-two of 69 patients in the treatment group (60.8%) became pregnant, whereas only 10 of 54 (18.5%) patients in the control group became pregnant after 8 months. Laparoscopic cauterization of endometriosis may increase the rate at which patients initially become pregnant. Sulewski et al. 85 treated 100 consecutive patients with mild or moderate endometriosis with laparoscopic electrocautery. This resulted in a crude PR of 40% over a 37-month follow-up. Of the 40 patients who became pregnant, 73% of the pregnancies occurred in the 1st 6 months and 88% of the pregnancies occurred in the 1st twelve months, which is higher than traditionally reported with medical treatment or laparotomy. Seventy-five percent of pregnancies after laparoscopic resection of an endometrioma occurred within the first six months. 50 No significant difference was noted between treatment with danazol and laparoscopic electrocautery. Seiler et al. 88 randomized patients with moderate endometriosis between danazol therapy and electrocoagulation of endometrial implants. The danazol group experienced pregnancy in 16 of 41 patients (39%), whereas the electrocautery group experienced pregnancy in 20 of 45 patients (44%) over a 7-month period of follow-up. Murphy et al.,90 using life table analysis and the two-parameter exponential method, studied 72 patients with stage I or stage II endometriosis who underwent laparoscopic electrocoagulation of the endometrial implants. The crude PR with an average follow-up period of 7.9 months was 74% for stage I and 57% for stage II. The estimated cure rates, using the two-parameter model, for stage I and II were
Pregnancy Rates After Laparoscopic Electrocoagulation of Endometriosis No. of pregnancies/no. treated
Author
Minimal
Mild
Moderate
Severe
Combined
Length of follow-up mo
Eward82 Hasson84,c Sulewski et al.85,d Daniell and PittawayBS Reich and McGiynn50 Seiler et al. 88" Nowroozi et al. 89.t Murphy et al.oo.t Total
4/7
(57)a
10/18 (56)b
0/1 (0) 20/42 (48)
4/5 (80)
24/36 (67)
20/45 (44) 42/69 (61) 18/36 (50)
2/7 (29)
0/3 (0)
28/44 (64)
110/210 (52)
24/67 (36)
4/8 (50)
a Values in parentheses are percents. Stage I by classification system of Mitchell and Farber.83 b Stage II by classification system of Mitchell and Farber. 83 C Clinical judgment used to evaluate the extent of disease: 1 = minimal; 2 = moderate; 3 = fairly extensive.
Vol. 55, No.4, April 1991
2/2 (100) 20/58 (35)
14/25 6/8 40/100 33/60 15/23 20/45 42/69 44/82
(56) (75) (40) (55) (65) (44) (61) (54)
13 7 37 18 7 8 8
214/412 (52)
Classification system not specified. Acosta classification system used. 87 f The Revised American Fertility Society classification system used. 32 d
e
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98.2% and 76.6%, respectively. The monthly fecundity for patients with endometriosis was only 10.3% for stage I and 7.59% for stage II. It is interesting to note that the majority of pregnancies in this study occurred within the 1st 6 months (71 %). Laparoscopic Treatment Utilizing Endocoagulation
Endocoagulation of endometrial implants has not been studied as widely in the English literature as electrocautery or laser vaporization. 35,62 Forty percent of 90 women with endometriosis treated with operative endoscopy and endocoagulation became pregnant.62 Laparoscopic Treatment Utilizing the Surgical Laser
The CO 2 laser has recently been the most widely used surgical laser for the treatment of endometriOSiS. 91 - 101 Use of the surgical laser in conjunction with operative laparoscopy offers the theoretical advantage of a more selective ablation of the endometrial implants while preserving normal tissue.102 The N d: YAG, argon, and KTP lasers have also been used to treat endometriosis. 43 ,103-105 Use of the surgicallaser has not improved the crude PR in comparison with other methods of ablation of endometriosis. The overall crude PR described in the literature for laparoscopic CO 2 laser vaporization of endometriosis is 59%, which is similar to the 52% described for both treatment at laparotomy and laparoscopic electrocoagulation of endometriosis. The overall crude PR reported in the literature for stage I, stage II, stage III, and stage IV is 59%, 58%, 58%, and 64%, respectively (Table 5). The results for stage IV are derived primarily from one study.ll2 Bruhat et al. 114 were the first to publish the use of the CO 2 laser through the laparoscope in 1979 followed by Tadir et al. ll5 in 1981. Use of the laparoscopic CO 2 laser in the United States was first reported in 1982 in both rabbits and 10 humans with mild or moderate endometriosis. The length of follow-up and the success rate (PR) were not reported. 101 Kelly and Roberts 100 were among the first to report PRs of patients with endometriosis treated laparoscopically with the CO 2 laser. A 6-month follow-up of 10 patients with stage I and II endometriosis resulted in a 60% crude PR. 1OO This study showed that laparoseopic treatment of endometriosis with the CO 2 laser was a viable alternative. Feste73 published the first large study describing his experience with laser laparoseopy of 202 patients, including laser transection of the uterosacral liga674
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Laparoscopic treatment of endometriosis
ments and vaporization of endometriotic implants on the bladder and bowel. A laser, 1 cm by 1 em, ablation of the uterosacral ligaments was performed on 42 patients with dysmenorrhea. Seventy-one percent of the patients had minimal or no dysmenorrhea after the procedure, whereas 23% had no change in symptoms and 4 % had worse symptoms. He also reported a 72% crude PR in 58 patients with stage I and II endometriosis, without other factors, treated by laparoscopic CO 2 laser with a follow-up period of 1 year. As late as 1985, a report was published that stated that laser laparoscopy was an effective form of treatment. 1OO This study required the use of a second 10-mm puncture site for delivery of the laser beam with a 2-mm spot size and power densities of 400 to 600 W /cm2' Martin published two similar reports in 1985 and 1986. 102 ,107 The data of the first study were included in the second. Thirty-four patients with endometriosis (stage I, II, or III) as the only identifiable etiology of infertility experienced an overall PR of 68% with a follow-up period of 12 to 44 months. Eighty-one additional patients with other associated infertility factors had a crude PR of 40% with the same follow-up period. Nezhat et al.97,112,116 have published a series of articles describing their clinical experience with videomonitoring systems and laparoscopic CO 2 laser vaporization of endometriosis. All patients were classified using the original AFS classification system. 113 A crude PR of 75.1%,62.7%,42.1%, and 50% for stages I, II, III, and IV, respectively, was reported in the initial series of 102 patients with an 18-month follow-up.97 The most recent study observed a crude PR of 71.8%,69.8%, 67.2%, and 68.6% for stages I, II, III, and IV, respectively, in a total of 243 patients. 112 The length of follow-up was not specified in the latter report, however, in the initial study 66% of the pregnancies occurred in the 1st 8 months after treatment, 29% 8 to 12 months after treatment, and only 5% 12 to 18 months after treatment. The majority of pregnancies occurred within the 1st 6 months after treatment, similar to the findings of Sulewski et al. 85 and Murphy et a1. 90 with laparoscopic electrocoagulation of endometriosis. The first study to use the R-AFS classification system32 reported an overall crude PR of 57% after 15 months of follow-up.96 The PRs for stages I to II, III, and IV were 64.5%, 57.7%, and 28.8%, respectively. Endometriomas were treated ifpenetration into the ovary was <3 cm. Patients were excluded from the study if the endometrioma was >5 cm in diameter. The cyst was aspirated and the cyst wall vaporized with the CO 2 laser. Fertility and Sterility
Table 5
Pregnancy Rates After Laparoscopic CO 2 Laser Vaporization of Endometriosis· No. of pregnancies/no. treated Stage I
Author
Stage II
Stage IV
Stage III
Length of follow-up
Combined
mo
Daniell and Brown 'OI Daniell and PittawayBS Kelly and Roberts 'OO Chong'06 Feste 73 Martin 102 Martin '07 Davis96•e Olive and Martin '08•f Donnez '09 •• Paulsen and Asmer95 •• Gast et al. 110,. Fayez et aU"·c Nezhat et al. '12•• Total
3/3 21/32 24/47 7/27 25/56
(100)
3/7
(43)
(66)b
(51) (26)
4/6 (66) 3/19 (16) (45)d 22/45 (49)d 20/31 (65)
2/5 1/4 9/14 15/26
(40) (25)C (64)C
(58)
2/7 (29)
3/10
(30)
5
3/15
(20)
6
6/10 21/32 30/58 11/50 56/115 37/64
(60) (66) (52) (22) (49) (58)
6 12 12 9 12 15
23/59 (39) 26/42 (62)
22/48 (46) 11/21 (52)
10/20 (50) 3/7 (43)
55/127 (43) 40/70 (57)
18
109/140 (78) 36/70 (51) 27/38 (71)
60/88 (68) 12/33 (38) 33/44 (75)
9/19 (47)
169/228 (74) 50/122 (41) 60/82 (73)
8 to 32 10 12
28/39 (72)
60/86 (70)
45/67 (67)
35/51 (69)
168/243 (69)
329/553 (59)
230/397 (58)
94/162 (58)
37/58 (64)
690/1170 (59)
• Values in parentheses are percents. The original American Fertility Society classification system is used unless noted. ll3 b Postop danazol X 132 days. c Postop danazol X 6 months. d 3-month course of danazol6 to 18 months postop if not pregnant.
Revised American Fertility Society classification system. 32 Patients treated with either a combination of laser laparoscopy only or a combination of laser laparoscopy and preop or postop danazol. • Patients with factors other than endometriosis excluded from study.
A large retrospective study by Olive and Martin 108 is one of the few in the literature using more in depth statistical analysis. Patient groups analyzed included: endometriosis only, endometriosis with other factors, the stage of endometriosis, and treatment with laser laparoscopy only or in combination with danazol treatment. Kaplan Meyer life table analysis was performed with monthly fecundity rates. There was no significant difference in the predicted PRs at 1, 2, or 3 years by stage of endometriosis. There were no statistically significant differences among any of the subgroups and the monthly fecundity rates. The monthly fecundity rates of stage I and stage II endometriosis with laser laparoscopy were comparable with those found with expectant management, danazol, and conservative surgery. It is interesting to note that the monthly fecundity rate in stage III endometriosis is 4.5%, whereas that observed with danazol and conservative surgery is approximately 1.5%. Using the two-parameter exponential model of Guzick and Rock,77 cumulative PRs of patients treated with laser laparoscopy are approximately the same as those observed with conservative surgery and danazol. It is also interesting to note that cu-
mulative PRs for stage I and stage II endometriosis treated with laser laparoscopy, danazol, and conservative surgery, as determined by the two-parameter exponential model, reveals a much higher initial cumulative PR with laser laparoscopy than with the other two treatment modalities (Fig. 5). Another retrospective study of 70 patients without controls, yielded crude PRs at 18 months of 62%,
Vol. 55, No.4, April 1991
e
f
0.7 0.6 ~
~
o.s
>
~
~
0.4
I 0.3 ~
;;;
~
(i
0.2
- . - . - LMer l8piIroecopy --------- ~ Surgery
0.0
o
, 6
12
,
1.
---00".,,,
,
,
,
24
30
31
Months
Figure 5 Cumulative PRs of patients with endometriosis treated with laparoscopic surgery, laparotomy, or danazol. (From Olive and Martin. 'OB Reproduced with permission of the publisher, The American Fertility Society).
Cook and Rock
Laparoscopic treatment of endometriosis
675
52%, and 42% for AFS stages I, II, and III, respectively.109 Gast et al. 110 studied 122 patients, 95 with at least one contributing factor in addition to endometriosis, using the R-AFS classification system. With a follow-up period of 2 to 32 months, the corrected crude PRs were 61 %,47%, and 54%, and the uncorrected crude PRs were 51 %,38%, and 47% for stages I, II, and III, respectively. No pregnancies occurred after 18 months of follow-up. Fayez et a1. 111 performed a retrospective study comparing the results of 238 patients with minimal and mild endometriosis treated with laparoscopy alone, danazol alone, or a combination of laparoscopy and danazol. The combination group used danazol postoperatively, 800 mg/d, for 6 months. The crude PRs for patients with minimal endometriosis treated with laparoscopy, danazol, and a combination of the two was 71%, 28%, and 55%, respectively. The crude PRs for patients with mild endometriosis were 75%, 25%, and 52%, respectively. The majority of pregnancies occurred within the 1st 6 months post-treatment. Second-look laparoscopy showed complete resolution of endometriosis in 84%, 0%, and 75%, respectively, of patients treated with laparoscopy, danazol, and a combination of the two.
of patients treated with operative laparoscopy become pregnant within the 1st 6 months after treatment.85,90,97,108 The monthly fecundity rates with laser laparoscopy alone or combination therapy are similar (Table 6). In light of the potential disadvantages of preoperative medical therapy and the lack of objective data demonstrating efficacy, the use of preoperative medical therapy may be best reserved for patients with severe disease in which preoperative medical treatment may allow for less extensive resection of disease and preservation of reproductive system. Postoperative medical therapy offers the theoretical advantage of eradicating residual or microscopic disease. The results of studies using postoperative danazol in patients with severe endometriosis are contradictory with both decreased and increased PRs in comparison with surgery aloneY7,1l8 Because most patients become pregnant within the first 6 months after laparoscopic treatment of endometriosis, postoperative medical treatment is probably best reserved for patients with residual disease or patients who are not actively pursuing pregnancy during this period. THE FUTURE
Combination Therapy
Combination treatment of endometriosis involves the use of either preoperative or postoperative medical treatment in an effort to improve treatment success. The use of preoperative medical treatment suppresses ovarian activity so that cystic structures related to ovulatory activity are not confused with endometriosis. Preoperative medical treatment also results in decreased inflammation, vascularity, and size of implants, which may allow for less extensive resection at surgery and potentially less adhesion formation. The potential disadvantages of preoperative medical treatment include: (1) the appearance of endometriosis during medical treatment may be more difficult to diagnose, resulting in a less complete resection; (2) the cost and potential side effects of medical treatment; and (3) the delay in the time to which the patient can begin to attempt pregnancy.53 Postoperative medical therapy may be beneficial if complete resection of endometriotic lesions cannot be accomplished or to eradicate remaining microscopic disease. The presence of microscopic disease has been demonstrated in normal appearing peritoneum and may contribute to both treatment failure and recurrence of endometriosis. 25 Postoperative medical treatment precludes the patient attempting pregnancy the 1st 6 months. The majority 676
Cook and Rock
Laparoscopic treatment of endometriosis
Fiber Optic Microendoscopy
Endoscopic surgery is rapidly evolving. Current technological developments may revolutionize the diagnosis and treatment of endometriosis. The currently available laparoscopes use a lens system developed by Dr. Hopkins in the 1960s. 119 The major
Table 6 Monthly Fecundity Rates With Laser Laparoscopy and Adjunctive Therapy·
Disease severity and treatment
No, of patients
Monthly fecundity rate
95% confidence limits %
Stage I endometriosis Laser only Preoperative danazol Postoperative danazol Stage II Laser only Preoperative danazol Postoperative danazol Stage III Laser only Preoperative danazol Postoperative danazol
44 13 2
3.5 1.6 3.5
1.8 to 4.9 o to 3,1 o to 10.2
22 21 5
2.5 4.4 2.5
0.7 to 4.4 2.0 to 6.8 o to 4.4
12 4 4
5.6 6.1 1.5
1.5 to 10.1 o to 14.5 o to 4.4
• Adapted from Olive and MartinYlS (Reproduced with permission of the publisher, The American Fertility Society).
Fertility and Sterility
disadvantage of this type of laparoscope is that it requires the use of general anesthesia. Fiber optic endoscopes are being developed with diameters as small as 0.25 mm. The diameter of the individual fibers in a fiber optic bundle is becoming smaller (the current limit is about 6 ~m), which allows for more elements in a given bundle size and thus increased resolution. In the future, diagnosis and staging of endometriosis may, be made in the office with local anesthesia and the fiber optic endoscope. The best treatment modality could then be selected before the need for general anesthesia. The potential even exists for the treatment of endometriosis at the time of microendoscopy with photodynamic therapy. Photodynamic Therapy
Photodynamic therapy is an experimental technique that may be used in conjunction with the laparoscope for the treatment of endometriosis in the future. This process utilizes selectively absorbed photosensitive chemicals that cause tissue destruction when exposed to a certain wavelength of light. The photosensitive chemical used currently is a purified hematoporphyrin derivative, dihematoporphyrin ether (DHE).120 A recent study used rabbit endometrial transplants to evaluate the potential use of photodynamic therapy in the treatment of endometriosis. l2l The animals were intravenously injected with DHE and exposed to 630 nm light (argon laser) 24 hours later. A power density of 100 J/cm2 resulted in complete destruction of 81 % of the transplants. There was no tissue destruction in the control animals that did not receive DHE but were exposed to the argon laser. The results of these studies using animal models are encouraging, however, further studies are needed before one can extrapolate these results to patients with endometriosis in the clinical setting.
of anatomic damage secondary to endometriosis is continually expanding. The experience of the surgeon is paramount in overcoming the technical difficulties encountered in endoscopic surgery. The primary advantage of the surgical laser lies in a more controlled penetration of tissue. Discussion pertaining to which treatment modality (excision, endocoagulation, electrocautery, or anyone of the various types of lasers) is most successful in the treatment of superficial endometriosis is missing the central issue. It does not matter how the endometriosis is ablated (all of the various treatment modalities available are capable of ablating endometriotic lesions). The critical issue is the ability of the surgeon to correctly identify endometriosis with its wide range of appearances and to utilize the various treatment modalities correctly to fully treat the disease. Variation in the success of reports utilizing different modes of ablation of superficial endometriosis is most likely related to a difference in the patient population, the skill of the surgeon, or inadequate statistical analysis. The most common form of statistical analysis used in reporting and comparing the success rates in the treatment of endometriosis has been the crude PRo The time has come to discard this outmoded and inaccurate definition of success. Both as individuals and as a group of physicians providing care to the infertile patient, we strive to provide the patient with the form of treatment that is most efficacious. The continued use of the crude PR as the primary statistical tool makes comparison of results difficult and hinders identification of successful treatment modalities. We call for inclusion of uniform in depth statistical analysis, including monthly fecundity, life table analysis, and two-parameter exponential analysis in future publications. This will allow for clarification of treatment success and continue to promote the advancement of the patient care provided by this medical subspecialty.
CONCLUSIONS
Laparoscopic treatment of endometriosis offers several advantages over other forms of therapy. The patient will usually undergo laparoscopy for diagnosis of endometriosis and thus can be treated without having to undergo a second surgical procedure. In addition, the patient does not have to accept the extended time or potential side effects of medical treatment. Laparoscopic treatment of endometriosis clearly results in reduced length of hospital stay and cost in comparison with laparotomy. The role of laparoscopic surgery in the correction Vol. 55, No.4, April 1991
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109. Donnez J: CO 2 laser laparoscopy in infertile women with endometriosis and women with adnexal adhesions. Fertil Steril 48:390, 1987 1l0. Gast MJ, Tobler R, Strickler RC, Odem R, Pineda J: Laser vaporization of endometriosis in an infertile population: the role of complicating factors. Fertil Steril 49:32, 1988 Ill. Fayez JA, Collazo LM, Vernon C: Comparison of different modalities of treatment for minimal and mild endometriosis. Am J Obstet GynecoI159:927, 1988 ll2. Nezhat C, Crowgey S, Nezhat F: Videolaseroscopy for the treatment of endometriosis associated with infertility. Fertil Steril 51:237, 1989 113. Classification of endometriosis. The American Fertility Society. Fertil Steril 32:633, 1979 ll4. Bruhat MA, Mage G, Pouly JL: Use of the CO 2 laser in laparoscopy. In Laser Surgery: Proceedings of the 3rd International Symposium on Laser Surgery, Edited by I Kaplan, PW Ascher. Tel Aviv, OT-PAZ Press, 1979, p 274 ll5. Tadir Y, Ovadia J, Zuckerman Z, Kaplan I: Laparoscopic application of the CO 2 laser. In Proceedings of the Fourth Congress of the International Society for Laser Surgery. Edited by K Atsumi, N Nimsakul. Tokyo, Japanese Society for Laser Medicine, 1981, p 25 ll6. Nezhat C, Crowgey SR, Garrison CP: Surgical treatment of endometriosis via laser laparoscopy and videolaseroscopy. Contrib Gynecol Obstet 16:303, 1987 ll7. Buttram VC, Jr, Reiter RC, Ward S: Treatment of endometriosis with danazol: report of a 6-year study. Fertil Steril 43:353, 1985 118. Wheeler JM, Malinak LR: Postoperative danazol therapy in infertility patients with severe endometriosis. Fertil Steril 36:460, 1981 ll9. Hulka JF: Biophysics and physiology. In Textbook of Laparoscopy. Orlando, Grune and Stratton, Inc., 1985, p 7 120. Dougherty TJ: Photodynamic therapy. In Endoscopic Laser Surgery Handbook, Edited by SM Shapshay. New York, Marcel Dekker Inc., 1987, p 424 121. Manyak MJ, Nelson LM, Solomon D, Russo A, Thomas GF, Stillman RJ: Photodynamic therapy of rabbit endometrial implants: a model treatment of endometriosis. Fertil Steril 52:140, 1989
Received September 4, 1990. * Reprint requests: John A. Rock, M.D., The Johns Hopkins Hospital, Department of Gynecology and Obstetrics, Division of Reproductive Endocrinology, Houck 247, 600 North Wolfe Street, Baltimore, Maryland 21205.
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Laparoscopic treatment of endometriosis
Fertility and Sterility