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Pneumatic device for the automated advancement of the fiberoptic endoscope for total colonoscopy—a preliminary report
Figure 9. Biliary endoprosthesis in a patient with large, noncrushable bile duct stones.
papillary biliary stent is effective, thus preventing stone impaction. We use the second generation lithotripter primarily in cases where any doubt exists as to whether the stone can be extracted in the conventional way. Technical failures can be corrected either by use of a second lithotripter or with the aid of other instruments, such as biopsy forceps or polypectomy snare.
Pneumatic device for the automated advancement of the fiberoptic endoscope for total colonoscopy-a preliminary report Paul H. Sugarbaker, MD William Z. Penland, MS James Lyddy, MS
Total colonscopy is not used as a method for screening the large bowel for cancer and polyps because it has been too expensive in terms of physician time and instrument cost to offset the number of carcinomas found in a general population.! Total colonscopy requires a highly trained physician for insertion and complete navigation of the endoscope and proper visual interpretation of the endoscopic findings. There are insufficient personnel and an inadequate number of endoscopes to consider colonoscopy for screening a large population. Moreover, total colonoscopy as a screening tool is not known or accepted as necessary From the Surgery Branch, Division of Cancer Treatment, National Cancer Institute, National Institutes of Health, Bethesda, Maryland. Reprint requests: Paul H. Sugarbaker, MD, Colorectal Cancer Section, Surgery Branch, National Cancer Institute, Bldg. 10, Room 2B07, Bethesda, Maryland 20205.
210
REFERENCES 1. Demling L, Koch H, Classen M, et a1. Endoskopische Papillotomie und Gallensteinentfemung. Dtsch Med Wochenschr 1974;99:2255. 2. Safrany L, Schott B, Gniige E, Neuhaus B. Spontanabgang groper Steine aus dem Choledochus. Dtsch Med Wochenschr 1981;108:1135. 3. Koch H, ROsch W, Walz V. Endoscopic lithotripsy in the bile duct. Gastrointest Endosc 1980;26:16. 4. Riemann JF, Seuberth K, Demling L. Clinical application of a new mechanicallithotripter for common bile duct stones. Scand J GastroenterolI982;17(supp1.)78:378. 5. Riemann JF, Seuberth K, Demling L. Mechanische Zertriimmenmg von Gallengangssteinen. Dtsch Med Wochenschr 1983;108:373. 6. Riemann JF, Demling L. Lithotripsy of bile duct stones. Endoscopy 1983;15:191. 7. Demling L, Seuberth K, Riemann JF. A mechanicallithotripter. Endoscopy 1982;14:100. 8. Riemann JF, Seuberth K, Demling L. Mechanical lithotripsy through the intact papilla of Vater. Endoscopy 1983;15:111. 9. Stock KP, Riemann JF. Tonnensteine im Ductus choledochus-Verlauf nach erfolgloser endoskopischer Extraktion. Therapiewoche 1983;33:5239. 10. Frimberger E, KUhner W, Weingart J, Ottenjann R. Eine neue Methode der elektrohydraulischen Cholelithotripsie (Lithoklasie). Dtsch Med Wochenschr 1982;107:213. 11. Staritz M, Ewe K, Meyer zum Biischenfelde KH. Endoscopic papillary dilatation, a possible alternative to endoscopic papillotomy? Lancet 1982;1:1306. 12. Riemann JF, Gierth K, Lux G, et a1. Die belassene Steingallenblase-ein Risikofaktor nach endoskopischer Papillotomie? Z Gastroenterol 1984;22:188.
by the general public. The inconvenience, discomfort, and cost that a patient must experience during this examination is not perceived to be commensurate with the gains from large bowel cancer screening. We describe an innovative approach to facilitate colonoscopy, especially screening procedures. When fully developed, the concept promises to expedite and simplify advancement of the colonic endoscope. INSTRUMENTATION AND METHODS
The problems of improved colonoscope navigation were addressed in 1976 by the Surgery Branch, National Cancer Institute, Bethesda, Maryland, in collaboration with Arthur D. Little, Inc., Cambridge, Massachusetts. Several concepts were considered which used inflatable cuffs to facilitate advancement of the colonoscope tip within the colon. A two-cuff system was developed in which cuff movement was accomplished by mechanical bellows, pistons, wire and pulleys, and finally, by a movable sleeve. Initial experience involved testing advancement principles with a glass tube colon model. The pneumatic rubber cuffs and sleeve advanced the endoscope easily, traversing a 90-cm distance in approximately 4 min; the concept was used for subsequent animal and human studies. GASTROINTESTINAL ENDOSCOPY
The self-advancing colonic endoscope (SACE) consists of an inflatable cuff system adapted to a single channel Olympus colonoscope (90 cm) and a separate air control unit (Fig. 1). Two low pressure inflatable latex rubber cuffs, approximately 20 mm diameter x 25 mm length, deflated, are mounted on the colonoscope (Fig. 2). The front cuff is fixed 70 mm from the tip of the colonoscope just behind the polydirectional tip. The rear cuff is fixed to a flexible sleeve. The sleeve is made of flexible plastic 15 cm shorter in length than the shaft of the colonoscope. Its internal diameter is 11 mm and its external diameter is 13 mm. This sleeve and rear cuff are moved back and forth
along the scope with a variable stroke (typically of 5.5 cm) under manual control of the endoscopist. Small diameter flexible air lines connect both cuffs to an air controller programmed to automatically inflate and deflate the cuffs. Control of cuff inflation pressures (4 to 7 pounds per square inch) and timing cycles is determined by the endoscopist through a pressure regulator, timing device, and gauge indicators. An external source of compressed CO 2 is required. The principles of scope advancement are illustrated in Figure 3. Introduction of the colonoscope into the anus is accomplished manually with both cuffs deflated and placed together in a closed position. In an
Figure 1. Early prototype SACE apparatus. Two inflatable cuffs and a sleeve are mounted on the gO-cm colonoscope. The inflatable cuffs are attached to air lines from a control unit that permits either automatic or manual cuff inflation/deflation and timing. The cuff inflation is controlled by a foot switch and sleeve movement by the endoscopist.
Figure 2. Latex cuffs with individual air lines. The position of the front cuff is fixed immediately below the flexible tip. The rear cuff is shown inflated. It is fixed to a flexible, free sliding sleeve that permits a 5-em stroke with the spiral air line.
VOLUME 31, NO.3, 1985
211
Figure 3.
Mode of action of SACE as described in the text.
idealized procedure repetitive advancement starts (step 1) when the rear cuff is inflated and gentle retrograde traction is placed on the sleeve. This straightens the colon and permits the endoscope to be pushed through the sleeve to advance the endoscope tip and the forward cuff. At this point (step 2), the forward cuff is inflated until it grips the colon wall and the rear cuff is deflated and brought forward by manual advance of the sleeve. Having reached a closed position, the rear cuff is inflated (step 3); with both cuffs gripping the colon wall and with gentle retrograde pressure, the colon is straightened for several centimeters. Endoscope advancement is accomplished in step 4, a repeat of step 1. This sequence of maneuvers would be repeated until the cecum is reached. When the cecum is entered light transmitted through the abdominal wall appears at McBurney's point and characteristic anatomic features of this portion of the large bowel are recognized (patulous lumen, appendiceal orifice, and ileocecal valve). At this point the control unit would be shut off. Although orientation within a particular anatomic segment of the colon is maintained while advancing SACE, careful visualization of the colon lumen would be performed while the endoscope is being withdrawn. The front cuff can be alternatively inflated and deflated to vary the lumen opening and facilitate visualization during withdrawal of the endoscope. Dogs were used as an experimental animal. Magnesium citrate was given by gastric intubation, a clear fluid diet was instituted, and 1% peroxide enemas were used to cleanse the large bowel. The endoscope was inserted with the automated advancing tip. The device moved through the dog colon without difficulty to the level of the hepatic flexure. Under continued general anesthesia the dog's abdomen was opened with a midline incision and the colon inspected. No damage 212
to the colon wall from the pneumatic cuffs was observed by careful gross inspection of the large bowel. A protocol (NIH 79-C-175) for limited use of this device in humans was prepared and given approval by the NIH Institutional Review Board. After obtaining informed consent, three patients with familial polyposis were colonoscoped by using the automated advancer prior to subtotal colectomy. Under general anesthesia a midline abdominal incision was performed to allow observation of SACE in action. The self-advancing colonic endoscope was introduced through the rectum. The apparatus was seen to move from the rectosigmoid, through the sigmoid, around the junction of sigmoid and descending colon, and up the descending colon to the hepatic flexure. It moved past the spleen without trauma, and the examination was completed to the midtransverse colon. The two cuffs, sleeve, and control apparatus functioned as expected. The latex balloons, which did not completely collapse, appeared to grip improperly and rupture. Rupture of one or the other latex balloons required the examination to be discontinued in all three patients. The colon was removed as planned and submitted to pathology. Careful gross and histologic study of the complete large bowel specimen gave no evidence of colonic damage from the pneumatic cuffs. DISCUSSION
It seems likely that the SACE could change, significantly, the cost-effectiveness ratio for total colonoscopy. By lowering the required skill level to advance the scope, by reducing procedure time, and by simplifying endoscope construction, the cost per procedure could be lowered. With present colonoscopic techniques the major limitation in the procedure is reaching the site of colon pathology. Navigation from anus GASTROINTESTINAL ENDOSCOPY
to cecum can be difficult and the requirement in terms of time difficult to predict. With this apparatus procedure time would be more predictable and routine colonic endoscopy would be greatly facilitated for the physician. A major portion of the physician's time could be spent in observation of the colon lumen rather than in endoscope advancement. A major problem with any screening procedure comes in acceptance of the procedure by a large segment of the population. It is hoped that SACE presents the possibility for less painful and rapid visualization of the entire large bowel. When using this device the endoscope is advanced by pulling the instrument into the colon rather than by pushing; therefore, painful stretching of the bowel wall and its mesentery should not occur with automated advancement. Secondly, the size and stiffness of endoscopes currently in use may not be required if the endoscope is pulled rather than pushed into the large bowel. An endoscope much smaller in diameter with much
Splenic cyst-definitive treatment by laparoscopy Barry Salky, MD, FACS Maurice Zimmerman, MD Joel Bauer, MD, FACS Irwin Gelemt, MD, FACS Isadore Kreel, MD, FACS
The historical treatment for symptomatic benign nonparasitic splenic cysts has been total splenectomy. A recent report has emphasized a more conservative approach using partial splenectomy whenever possible. I The rationale is to preserve viable, functioning splenic tissue, thereby eliminating the potentially fatal complication of post splenectomy sepsis. 2• 3 However, partial splenectomy is a technically challenging procedure with significant morbidity possible including total splenectomy. We recently treated a benign splenic cyst with decompression by direct laparoscopic puncture. To ensure against recurrence, creation of a splenic cystperitoneal window was performed laparoscopically. This report describes the technique and discusses the advantage over laparotomy and partial splenectomy. CASE REPORT
A 42-year-old white woman presented with a 4-year history of increasing epigastric pain and retrosternal discomfort. She dated the symptoms to an automobile accident 4 From the Departments of Surgery and Gastroenterology, Mount Sinai Sclwol of Medicine of the City University of New York and The Mount Sinai Hospital, New York, New York. Reprint requests: Barry Salky, MD, 25 East 69th Street, New York, New York 10021. VOLUME 31, NO.3, 1985
greater flexibility may be used if the automated advancer moves the endoscopic tip. In the future we see a multicuffed pneumatic apparatus which exerts a peristaltic-like propulsive force for advancing the endoscope through the colon. This apparatus would propel itself in a proximal direction into the colon very similarly to the way a bolus of stool is propelled distally within the large bowel. Commercial development and clinical trials are now in progress to establish improved instrumentation, technique, and patient acceptance. * REFERENCE 1. Sugarbaker PH, McDonald JS, Gunderson LL. Colorectal can-
cer. In: DeVita VT Jr, Hellman S, Rosenberg SA, eds. Principles and practice of oncology. Philadelphia: JB Lippincott, 1982:643-723.
* Collaborative studies are currently in progress between the National Cancer Institute, Bethesda, Maryland, and Medquest, Inc., a subsidiary of Plasmedics, Inc., Englewood, Colorado.
years earlier in which a steering wheel injury to the left anterior chest occurred. No rib fractures or intraabdominal pathology were documented. She required no further medical attention until 3 years later. At that time, her primary complaints were epigastric pain, belching, and retrosternal discomfort. Upper gastrointestinal series and oral cholecystogram were normal. Because of increasing symptomatology, a sonogram was obtained which revealed a large cystic mass in the left upper quadrant. CT scan confirmed a large splenic cyst with compression of the lateral wall of the stomach (Fig. 1). Upper gastrointestinal endoscopy demonstrated a hiatal hernia with reflux esophagitis on biopsy. Physical examination was within normal limits. Because of the left upper quadrant pain and recent increase in reflux esophagitis thought secondary to pressure from the cyst, laparoscopy was performed. General anesthesia was used as significant electrocautery was necessary. A large benign epidermoid splenic cyst was confirmed. Decompression was accomplished and a splenic cyst-peritoneal window was created. The patient's esophageal reflux symptoms stopped immediately after laparoscopy. Minimal doses of Percocet@ were required for analgesia. She was discharged on postoperative day 4. CT scan 2 months after laparoscopy revealed a 2-cm defect in the spleen. Repeat CT scan 8 months later showed a minimal splenic defect with demonstration of the splenoperitoneal window (Fig. 2). She has remained asymptomatic 11 months following the procedure.
TECHNIQUE
After induction of general anesthesia and sterile preparation of the abdominal wall, pneumoperitoneum and lO-mm laparoscopic trocar placement were 213
papillary biliary stent is effective, thus preventing stone impaction. We use the second generation lithotripter primarily in cases where any doubt exists as to whether the stone can be extracted in the conventional way. Technical failures can be corrected either by use of a second lithotripter or with the aid of other instruments, such as biopsy forceps or polypectomy snare.
Pneumatic device for the automated advancement of the fiberoptic endoscope for total colonoscopy-a preliminary report Paul H. Sugarbaker, MD William Z. Penland, MS James Lyddy, MS
Total colonscopy is not used as a method for screening the large bowel for cancer and polyps because it has been too expensive in terms of physician time and instrument cost to offset the number of carcinomas found in a general population.! Total colonscopy requires a highly trained physician for insertion and complete navigation of the endoscope and proper visual interpretation of the endoscopic findings. There are insufficient personnel and an inadequate number of endoscopes to consider colonoscopy for screening a large population. Moreover, total colonoscopy as a screening tool is not known or accepted as necessary From the Surgery Branch, Division of Cancer Treatment, National Cancer Institute, National Institutes of Health, Bethesda, Maryland. Reprint requests: Paul H. Sugarbaker, MD, Colorectal Cancer Section, Surgery Branch, National Cancer Institute, Bldg. 10, Room 2B07, Bethesda, Maryland 20205.
210
REFERENCES 1. Demling L, Koch H, Classen M, et a1. Endoskopische Papillotomie und Gallensteinentfemung. Dtsch Med Wochenschr 1974;99:2255. 2. Safrany L, Schott B, Gniige E, Neuhaus B. Spontanabgang groper Steine aus dem Choledochus. Dtsch Med Wochenschr 1981;108:1135. 3. Koch H, ROsch W, Walz V. Endoscopic lithotripsy in the bile duct. Gastrointest Endosc 1980;26:16. 4. Riemann JF, Seuberth K, Demling L. Clinical application of a new mechanicallithotripter for common bile duct stones. Scand J GastroenterolI982;17(supp1.)78:378. 5. Riemann JF, Seuberth K, Demling L. Mechanische Zertriimmenmg von Gallengangssteinen. Dtsch Med Wochenschr 1983;108:373. 6. Riemann JF, Demling L. Lithotripsy of bile duct stones. Endoscopy 1983;15:191. 7. Demling L, Seuberth K, Riemann JF. A mechanicallithotripter. Endoscopy 1982;14:100. 8. Riemann JF, Seuberth K, Demling L. Mechanical lithotripsy through the intact papilla of Vater. Endoscopy 1983;15:111. 9. Stock KP, Riemann JF. Tonnensteine im Ductus choledochus-Verlauf nach erfolgloser endoskopischer Extraktion. Therapiewoche 1983;33:5239. 10. Frimberger E, KUhner W, Weingart J, Ottenjann R. Eine neue Methode der elektrohydraulischen Cholelithotripsie (Lithoklasie). Dtsch Med Wochenschr 1982;107:213. 11. Staritz M, Ewe K, Meyer zum Biischenfelde KH. Endoscopic papillary dilatation, a possible alternative to endoscopic papillotomy? Lancet 1982;1:1306. 12. Riemann JF, Gierth K, Lux G, et a1. Die belassene Steingallenblase-ein Risikofaktor nach endoskopischer Papillotomie? Z Gastroenterol 1984;22:188.
by the general public. The inconvenience, discomfort, and cost that a patient must experience during this examination is not perceived to be commensurate with the gains from large bowel cancer screening. We describe an innovative approach to facilitate colonoscopy, especially screening procedures. When fully developed, the concept promises to expedite and simplify advancement of the colonic endoscope. INSTRUMENTATION AND METHODS
The problems of improved colonoscope navigation were addressed in 1976 by the Surgery Branch, National Cancer Institute, Bethesda, Maryland, in collaboration with Arthur D. Little, Inc., Cambridge, Massachusetts. Several concepts were considered which used inflatable cuffs to facilitate advancement of the colonoscope tip within the colon. A two-cuff system was developed in which cuff movement was accomplished by mechanical bellows, pistons, wire and pulleys, and finally, by a movable sleeve. Initial experience involved testing advancement principles with a glass tube colon model. The pneumatic rubber cuffs and sleeve advanced the endoscope easily, traversing a 90-cm distance in approximately 4 min; the concept was used for subsequent animal and human studies. GASTROINTESTINAL ENDOSCOPY
The self-advancing colonic endoscope (SACE) consists of an inflatable cuff system adapted to a single channel Olympus colonoscope (90 cm) and a separate air control unit (Fig. 1). Two low pressure inflatable latex rubber cuffs, approximately 20 mm diameter x 25 mm length, deflated, are mounted on the colonoscope (Fig. 2). The front cuff is fixed 70 mm from the tip of the colonoscope just behind the polydirectional tip. The rear cuff is fixed to a flexible sleeve. The sleeve is made of flexible plastic 15 cm shorter in length than the shaft of the colonoscope. Its internal diameter is 11 mm and its external diameter is 13 mm. This sleeve and rear cuff are moved back and forth
along the scope with a variable stroke (typically of 5.5 cm) under manual control of the endoscopist. Small diameter flexible air lines connect both cuffs to an air controller programmed to automatically inflate and deflate the cuffs. Control of cuff inflation pressures (4 to 7 pounds per square inch) and timing cycles is determined by the endoscopist through a pressure regulator, timing device, and gauge indicators. An external source of compressed CO 2 is required. The principles of scope advancement are illustrated in Figure 3. Introduction of the colonoscope into the anus is accomplished manually with both cuffs deflated and placed together in a closed position. In an
Figure 1. Early prototype SACE apparatus. Two inflatable cuffs and a sleeve are mounted on the gO-cm colonoscope. The inflatable cuffs are attached to air lines from a control unit that permits either automatic or manual cuff inflation/deflation and timing. The cuff inflation is controlled by a foot switch and sleeve movement by the endoscopist.
Figure 2. Latex cuffs with individual air lines. The position of the front cuff is fixed immediately below the flexible tip. The rear cuff is shown inflated. It is fixed to a flexible, free sliding sleeve that permits a 5-em stroke with the spiral air line.
VOLUME 31, NO.3, 1985
211
Figure 3.
Mode of action of SACE as described in the text.
idealized procedure repetitive advancement starts (step 1) when the rear cuff is inflated and gentle retrograde traction is placed on the sleeve. This straightens the colon and permits the endoscope to be pushed through the sleeve to advance the endoscope tip and the forward cuff. At this point (step 2), the forward cuff is inflated until it grips the colon wall and the rear cuff is deflated and brought forward by manual advance of the sleeve. Having reached a closed position, the rear cuff is inflated (step 3); with both cuffs gripping the colon wall and with gentle retrograde pressure, the colon is straightened for several centimeters. Endoscope advancement is accomplished in step 4, a repeat of step 1. This sequence of maneuvers would be repeated until the cecum is reached. When the cecum is entered light transmitted through the abdominal wall appears at McBurney's point and characteristic anatomic features of this portion of the large bowel are recognized (patulous lumen, appendiceal orifice, and ileocecal valve). At this point the control unit would be shut off. Although orientation within a particular anatomic segment of the colon is maintained while advancing SACE, careful visualization of the colon lumen would be performed while the endoscope is being withdrawn. The front cuff can be alternatively inflated and deflated to vary the lumen opening and facilitate visualization during withdrawal of the endoscope. Dogs were used as an experimental animal. Magnesium citrate was given by gastric intubation, a clear fluid diet was instituted, and 1% peroxide enemas were used to cleanse the large bowel. The endoscope was inserted with the automated advancing tip. The device moved through the dog colon without difficulty to the level of the hepatic flexure. Under continued general anesthesia the dog's abdomen was opened with a midline incision and the colon inspected. No damage 212
to the colon wall from the pneumatic cuffs was observed by careful gross inspection of the large bowel. A protocol (NIH 79-C-175) for limited use of this device in humans was prepared and given approval by the NIH Institutional Review Board. After obtaining informed consent, three patients with familial polyposis were colonoscoped by using the automated advancer prior to subtotal colectomy. Under general anesthesia a midline abdominal incision was performed to allow observation of SACE in action. The self-advancing colonic endoscope was introduced through the rectum. The apparatus was seen to move from the rectosigmoid, through the sigmoid, around the junction of sigmoid and descending colon, and up the descending colon to the hepatic flexure. It moved past the spleen without trauma, and the examination was completed to the midtransverse colon. The two cuffs, sleeve, and control apparatus functioned as expected. The latex balloons, which did not completely collapse, appeared to grip improperly and rupture. Rupture of one or the other latex balloons required the examination to be discontinued in all three patients. The colon was removed as planned and submitted to pathology. Careful gross and histologic study of the complete large bowel specimen gave no evidence of colonic damage from the pneumatic cuffs. DISCUSSION
It seems likely that the SACE could change, significantly, the cost-effectiveness ratio for total colonoscopy. By lowering the required skill level to advance the scope, by reducing procedure time, and by simplifying endoscope construction, the cost per procedure could be lowered. With present colonoscopic techniques the major limitation in the procedure is reaching the site of colon pathology. Navigation from anus GASTROINTESTINAL ENDOSCOPY
to cecum can be difficult and the requirement in terms of time difficult to predict. With this apparatus procedure time would be more predictable and routine colonic endoscopy would be greatly facilitated for the physician. A major portion of the physician's time could be spent in observation of the colon lumen rather than in endoscope advancement. A major problem with any screening procedure comes in acceptance of the procedure by a large segment of the population. It is hoped that SACE presents the possibility for less painful and rapid visualization of the entire large bowel. When using this device the endoscope is advanced by pulling the instrument into the colon rather than by pushing; therefore, painful stretching of the bowel wall and its mesentery should not occur with automated advancement. Secondly, the size and stiffness of endoscopes currently in use may not be required if the endoscope is pulled rather than pushed into the large bowel. An endoscope much smaller in diameter with much
Splenic cyst-definitive treatment by laparoscopy Barry Salky, MD, FACS Maurice Zimmerman, MD Joel Bauer, MD, FACS Irwin Gelemt, MD, FACS Isadore Kreel, MD, FACS
The historical treatment for symptomatic benign nonparasitic splenic cysts has been total splenectomy. A recent report has emphasized a more conservative approach using partial splenectomy whenever possible. I The rationale is to preserve viable, functioning splenic tissue, thereby eliminating the potentially fatal complication of post splenectomy sepsis. 2• 3 However, partial splenectomy is a technically challenging procedure with significant morbidity possible including total splenectomy. We recently treated a benign splenic cyst with decompression by direct laparoscopic puncture. To ensure against recurrence, creation of a splenic cystperitoneal window was performed laparoscopically. This report describes the technique and discusses the advantage over laparotomy and partial splenectomy. CASE REPORT
A 42-year-old white woman presented with a 4-year history of increasing epigastric pain and retrosternal discomfort. She dated the symptoms to an automobile accident 4 From the Departments of Surgery and Gastroenterology, Mount Sinai Sclwol of Medicine of the City University of New York and The Mount Sinai Hospital, New York, New York. Reprint requests: Barry Salky, MD, 25 East 69th Street, New York, New York 10021. VOLUME 31, NO.3, 1985
greater flexibility may be used if the automated advancer moves the endoscopic tip. In the future we see a multicuffed pneumatic apparatus which exerts a peristaltic-like propulsive force for advancing the endoscope through the colon. This apparatus would propel itself in a proximal direction into the colon very similarly to the way a bolus of stool is propelled distally within the large bowel. Commercial development and clinical trials are now in progress to establish improved instrumentation, technique, and patient acceptance. * REFERENCE 1. Sugarbaker PH, McDonald JS, Gunderson LL. Colorectal can-
cer. In: DeVita VT Jr, Hellman S, Rosenberg SA, eds. Principles and practice of oncology. Philadelphia: JB Lippincott, 1982:643-723.
* Collaborative studies are currently in progress between the National Cancer Institute, Bethesda, Maryland, and Medquest, Inc., a subsidiary of Plasmedics, Inc., Englewood, Colorado.
years earlier in which a steering wheel injury to the left anterior chest occurred. No rib fractures or intraabdominal pathology were documented. She required no further medical attention until 3 years later. At that time, her primary complaints were epigastric pain, belching, and retrosternal discomfort. Upper gastrointestinal series and oral cholecystogram were normal. Because of increasing symptomatology, a sonogram was obtained which revealed a large cystic mass in the left upper quadrant. CT scan confirmed a large splenic cyst with compression of the lateral wall of the stomach (Fig. 1). Upper gastrointestinal endoscopy demonstrated a hiatal hernia with reflux esophagitis on biopsy. Physical examination was within normal limits. Because of the left upper quadrant pain and recent increase in reflux esophagitis thought secondary to pressure from the cyst, laparoscopy was performed. General anesthesia was used as significant electrocautery was necessary. A large benign epidermoid splenic cyst was confirmed. Decompression was accomplished and a splenic cyst-peritoneal window was created. The patient's esophageal reflux symptoms stopped immediately after laparoscopy. Minimal doses of Percocet@ were required for analgesia. She was discharged on postoperative day 4. CT scan 2 months after laparoscopy revealed a 2-cm defect in the spleen. Repeat CT scan 8 months later showed a minimal splenic defect with demonstration of the splenoperitoneal window (Fig. 2). She has remained asymptomatic 11 months following the procedure.
TECHNIQUE
After induction of general anesthesia and sterile preparation of the abdominal wall, pneumoperitoneum and lO-mm laparoscopic trocar placement were 213