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Frontoethmoidectomy with sewall-boyden reconstruction
CURRENT CONCEPTS IN THE SURGICAL MANAGEMENTOF FRONTAL SINUS DISEASE
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FRONTOETHMOIDECTOMY WITH SEWALL-BOYDEN RECONSTRUCTION Indications, Technique, and Philosophy Andrew H. Murr, MD, and Herbert H. Dedo, MD
This article discusses an interesting spin on an old approach to the surgical management of frontal sinus disease: frontoethmoidectomy with Sewall-Boyden flap reconstruction. The discussion emphasizes technique, because a lack of understanding of the intricacies of the technique is clearly the main impediment to widespread use of the approach. Also included are the authors' experience with the approach over many years and a discussion of indications, risks, and complications. HISTORY It is ironic that nearly all the anatomic and surgical innovations in frontal sinus surgery and the understanding of the frontal recess are more than 100 years old. Turn-of-the-century textbooks are replete with detailed anatomic and surgical descriptions of the frontal sinus and the surgical approaches to it. Hajek has exquisitely detailed anatomic descriptions of the frontal recess in the English translation of his 1926 text.17In this same textbook, an extraordinary discussion of transnasal and open surgical approaches is exhaustively reviewed with references to then-current literature which fill many pages of bibli~graphy.'~ In the United States, the great anatomist at Jefferson Medical College, J. Parsons Schaeffer, published a From the Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco School of Medicine, San Francisco, California
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textbook in 1920 that could be mistaken for a modern publication, right down to his anatomic and embryologic descriptions of the frontal recess and his actual use of the term frontal ~ecess.’~ Schaeffer also includes descriptions and illustrations of what has been recently classified as a type I F frontal recess cell, predating this new classificationby 70 years.29Interestingly, Schaeffer’s work was an expansion of a text written by Warren B. Davis, also of the Jefferson Medical College, in 1914. Davis’ text also delineates the frontal recess boundaries and discusses the structure of agger nasi cells as they relate to the uncinate process.1° It is relatively easy to understand why anatomists and physicians at the turn of the century were so interested in the frontal sinus and frontal recess. In that era before antibiotics empyema of the frontal sinus was relatively common, and fulminant acute sinusitis often led to meningitis and subsequent death. A. Logan Turner has a seemingly mundane chapter, including clinical photographs, of just such problems in his 1932 textbook Diseuses of the Eau, Nose, and Thuoat.3l In fact, authors including Turner and Reynolds,3* Grunewald,’6 and Braun7 wrote entire textbooks on septic thrombophlebitic complications.Catheterization of the frontal sinus was discussed in almost every textbook, usually in the early chapters where the more basic procedures used in everyday practice were positioned.20Obviously, this exhaustive coverage of the frontal sinus was stimulated by the frequently severe and sometimes fulminant infection of these awkwardly positioned paranasal sinus cells. With this frequency of frontal sinus infection and the possibility of devastating subsequent intracranial complication, surgeons became quite adept at interveningin an attempt to limit osteomyelitis,progressivethrombophlebitis,meningitis,brain suppuration, and death. Procedures involved two approaches: direct external drainage or transnasal drainage. The former was often accompanied by scarring at the site of incision, and the latter was often accompanied by failure to drain the infected sinus adequately or by intracranial penetration. The tendency for intracranial penetration led Harris P. Mosher to proclaim that the transnasal approach was one of the easiest ways to kill a patient.’l In both types of procedures, long-term clinical follow-up often revealed stubborn restenosis of the drainage opening. Without modern endoscopes or the luxury of computed tomographic (CT) imaging, follow-up was accomplished with plain film radiology and blind probing of the opening. The frontoethmoidectomy with Sewall reconstruction was an external approach based on the standard Lynch procedure described by Lynch in 1921= but with one major difference: there was an attempt to use a local septal mucosal flap to reconstruct the newly cleared frontal drainage t r a ~ k .The ~ ~modification ,~~ was deemed necessary because with the Lynch procedure stenosis of the neoduct was experienced approximately one third of the time.24McNaughP3and SewalPO reported the use of the septal mucosal flap in the mid-l930s, and Boyden: Ogura,26and Baron and Dedo’ resurrected the concept in the late 1950s and early 1960s. Other literature on the Lynch procedure was almost totally devoted to trying to find the perfect stent material so that the track would remain patent.25Many
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clinicians tried a great array of substances, including tantalum, polytetrafluoroethylene, silicone rubber, and red rubber, either as a tube, a roll, a stent, or a sheet. None of the variations seemed to prevent stenosis. What did seem to lessen the frequency of stenosis, however, was the mucosal flap, for which very high permanent patency rates were reported. At this time, however, the popularity of the obliterative approach, as resurrected by Bergara; and Goodale and M~ntgomery,'~ was also growing. As this obliterative approach became more popular, the Sewall-Boyden approach fell into disuse and was used by only a few surgeons. INDICATIONS There are no absolute indications for the Sewall-Boyden frontoethmoidectomy technique; rather, there are relative indications based on the type and extent of frontal sinus disease and the surgeon's preference for and comfort with a variety of available technologies. In broadest terms, the Sewall-Boyden technique should be considered for acute frontal sinusitis that is refractory to antibiotic therapy. These situations are sometimes complicated by periorbital cellulitis and abscess or anterior table cellulitis and Pott's puffy tumor. These situations are rare today with the widespread use of powerful antibiotics, but the occasional urgent case still requires surgical drainage. Other treatment options include a frontal trephination or an endoscopic approach to the frontal recess, but the Sewall-Boyden technique remains a reasonable option providing quick and direct access to the disease in what is sure to be a hyperemic and inflamed surgical field. Chronic frontal sinusitis refractory to adequate medical therapy is another relative indication for Sewall-Boyden frontoethmoidectomy. The procedure typically receives more serious consideration after endoscopic surgical approaches have failed and is often considered at the same time that frontal drillout2,'2 procedures enter the clinical algorithm. The SewallBoyden approach offers the familiarity and comfort of binocular and normal vision and the use of readily available instrumentation and drills. Most centers recommending the endoscopic Lothrop approach are equipped with special drills, microd6briders, and computerized stereotactic navigation systems. The cases requiring this type of surgery are infrequently encountered, and if specialized equipment is lacking it may be more prudent to rely on more readily and easily available instrumentation. A large frontal mucocele resting on dura is another excellent indication for the Sewall-Boyden approach. Here, the risk of leaving retained mucocele lining on the dura would be difficult to avoid and is therefore an obvious limitation of the osteoplastic obliteration approach, in which all mucosa must absolutely be removed. The Sewall-Boyden technique eliminates the need to remove the mucosal lining of the mucocele completely. The reconstruction of the frontal drainage tract allows complete marsupialization of the sinus, preventing recurrence of the mucocele. It also allows endoscopic and radiologic follow-up of the sinus; the preclusion of such follow-up is a limitation of the obliterative approach. A good alternative
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approach for a mucocele on dura is the endoscopic approach as popularized by Kennedy." Nevertheless, the Sewall-Boyden technique offers an equally functional method for marsupializing a mucocele on dura. Finally, the Sewell-Boyden frontoethmoidectomy is an alternative for addressing certain types of bone tumors such as osteomas. Here, the endoscopic approach is obviously limited in terms of access, whereas the external frontoethmoid approach offers good exposure for a drill and the Sewall mucosal flap preserves good frontal sinus drainage and aeration, eliminating the need for osteoplastic obliteration. TECHNIQUE
The surgical technique" for frontoethmoidectomywith Sewall-Boyden reconstruction is familiar to most surgeons who have been schooled in the technique of external frontoethmoidectomy.The Sewell-Boyden modification simply adds a mucosal rotational flap from the dorsum of the nose which relines the frontal recess, rather than relying on a stent or tube to attempt to force scar tissue to reline the recess (Fig. 1A and B). The procedure is conducted under general anesthesia. A tarsorrhaphy stitch or corneal shield is placed in the usual fashion. An external ethmoidectomy incision is outlined midway between the medial canthus and the nasion. The incision is brought to the medial tip of the eyebrow and to the bottom of the nasal pyramid, but it does not need to extend to the level of the nostril (Fig. 2 4 . It can be helpful to include a running W-plasty in the incision to prevent webbing and shortening of the future scar. Branches of the angular artery are encountered just beneath the skin,
Figure 1. A, Sagittal view of flap location on septum. 6,Frontal view of lateral Sewall-Boyden flap in place. (FromDedo HH, Broberg TA, Murr AH: Frontoethmoidectomywith Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
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Figure 2. A, Incision only to inferior medial edge of eyebrow. 6,Area of bone removal: lateral nasal bone and over anterior inferior frontal sinus. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 123, 1998; with permission.)
and care should be taken to identify and ligate the vessels securely or to use a bipolar cautery on them individually. If they are not arrested properly, they can obscure the field with blood throughout the procedure. The incision is brought down to periosteum which is divided with #15 blade. Using a Cottle elevator in one hand and a Frazier suction in the other, the surgeon raises the periosteum back to the level of the anterior ethmoid artery along the frontoethmoid suture line. This suture line delineates the approximate level of the skull base, and the anterior ethmoid artery delineates the level where the fovea ethmoidalis begins its rise to become the back wall of the frontal sinus. A hemaclip is placed on the anterior ethmoid artery. The lacrimal sac is retracted laterally but not incised, and the orbital periosteum and its contents are retracted with a Sewall retractor. The trochlea may be elevated with the orbital periosteal contents in continuity. An external ethmoidectomy is accomplished in the usual fashion, beginning by entering the ethmoid cavity in the lacrimal sac fossa and working posteriorly to the sphenoid and anteriorly into the frontal sinus. An otologic drill is used to outline a roughly rectangular nasal bony plate that is then removed. Grooves are made with a small rotating cutting burr down to the level of the internal nasal mucoperiostium (Fig. 2 B ) . This bone rectangle includes the nasal bone, nasal process of the frontal bone, and the nasal process of the maxilla. The bone plate is elevated with technique similar to that used for elevating a retrosigmoid bone flap in neurotologic surgery (Fig. 3). This procedure exposes the nasal mucosa of the upper nasal vault, the area where osteotomies in rhinoplasty are usually cut with a medially and laterally placed osteotome.
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Figure 3. Lateral nasal pyramid bony plate removal to expose flap. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction:Alive and well, a 25 year experience. American Journal of Rhinology 12:3,1998; with permission.)
The delta area or nasal beak is then drilled under direct visualization with a diamond or cutting otologic burr to the plane of the septum (Fig. 4). A Cottle elevator is used to elevate the septal mucosal flap off the perpendicular plate of the ethmoid and quadrangular cartilage (Fig. 5 ) . Two perpendicular cuts are made (designated A and B in Figure 6 ) . A fair amount of bleeding results from these cuts. A third parallel cut is made (designated C in Figure 7) which allows the septal mucosal flap to be swung up against the orbital periosteum and into the frontal sinus (Fig. 8A and B ) . The flap can then be secured with one or two 4-0 plain gut tacking sutures to the orbital periosteum (Fig. 9). If desired, a stent or 14-French red rubber catheter can be placed to hold the flap gently in position for 7 or 10 days. The timing of the stent placement is variable. The incisionis closed in a routine, careful fashion with special attention paid to reconstituting the medial canthal tendon attachment. The skin is usually closed with a 6-0 nylon, or a subcuticular type suture may be used. A drain is not placed, but a nasal pack may be placed if needed.
RESULTS The experience on which this article is based is a 25-year surgical practice. The results were published in 1998 in The American Journal of Rhinology." Forty-one patients were reviewed, encompassing 25 years of
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Figure 4. Removal of delta area. Frontal sinus and nasal mucosa is exposed. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
Figure 5. Entering frontal sinus with creation of microflap, and elevating nasal mucosa off upper septum. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with SewallBoyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
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Figure 6. Making posterior Sewall incision in septa1 and lateral nasal mucosa (Cut A). (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomywith Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
practice from 1970 to 1995. Thirty-six of the 41 who had adequate records for the purposes of documentation were included in the review. Follow-up ranged from 2 months to 24 years and 8 months. The nasofrontal track remained open in 35 of 36 patients in this report. One patient with aspergillosis for whom surgery was not initially successful had successful revision surgery. Twenty patients had either postoperative CT scans (13) or plain
Figure 7. Anterior incision in nasal rnucosa (Cut 6). (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectorny with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
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Figure 8. A, Cut C betweenends of A and B on septa1 mucosa alone has freed Sewall-Boyden flap. B, Flap based on lateral nasal wall with free end rotating up into frontal sinus. (FromDedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3;1998; with permission.)
film radiographs (7),and 85% (17 of 20) of these demonstrated aeration of the frontal sinus. In two patients, polyps requiring further removal caused the lack of aeration. The other patient had an interval infection which cleared with antibiotic therapy. This report indicates that the technique of mucosal flap reconstruction after frontoethmoidectomy is more successful than using stents or tubes alone. This finding is no surprise. Boyden
Figure 9. Laterally based flap in place with upper end extending to the floor of the frontal sinus. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction:Alive and well, a 25 year experience.American Journal of Rhinology 12:3,1998; with permission.)
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reported a 100% symptom-free rate over a 17-year period using the technique in 57 patient^.^ In 1960, Ogura reported success in 19 of 20 patients.26 More recently, Porto reviewed 50 cases with long-term follow-up and reported an 86% success rate.27
DISCUSSION With the demonstrated success of the Sewall-Boydentechnique firmly reported in the literature, why do so few surgeons embrace the procedure? The lack of enthusiasm for it is based first on the difficulty in visualizing exactly where the flap is created. The location is difficult to diagram and difficult to learn from drawings, because the location of the flap is not intuitive. The flap technique is nevertheless easy to practice in the anatomy laboratory and to teach in the operating room. The attempt to avoid obliterating the frontal sinus and to create a functional drainage track is quite in vogue of late. The advantages of a functioning sinus include the ability to follow the sinus radiologically in the future, and the ability to examine the sinus in the office setting with rigid or flexible scopes. Preservation of a functioning sinus can also be helpful when it would be difficult to exenterate the frontal sinus mucosa completely, as when a mucocele rests on dura or when there is extensive supraorbital pneumatization. Problems with osteoplastic obliteration can also arise many years after surgery and therefore require very extensive follow-up. Because of this potential for postoperative mucocele formation and postoperative infection many years after the original surgery, many surgeons argue that transnasal frontal sinus preservation is often better than obliteration by an osteoplastic approach. Reports of transnasal frontal sinus marsupialization abound in the literature. Techniques have been l5 Draf,” Casiano; Jacobs,’s and other^.^ reported by Schaefer,2s Enthusiasm has built for an endoscopic Lothrop approach to the frontal sinus whereby the top of the nasal septum is drilled away to approach the frontal sinus septum: excellent, though short-term, results have been reported with regard to patency? l4 The Sewall-Boyden frontoethmoidectomy is conceptually equivalent to these endoscopic approaches except that it is accomplished by a small external ethmoidectomy incision. It has all the advantages of these endoscopic approaches in preserving function and has the further advantages of relative technical simplicity, excellent exposure of the external ethmoidectomy approach, and the ability to create a septa1 mucosal flap to line the frontal recess. Certainly, the longterm follow-up of the technique has been well established during the last 50 years. Disadvantages of the Sewall-Boyden technique include the external scar in the medial canthal region. In most patients the scar can be cosmetically well hidden. Concerns about diplopia are valid, but problems should be minimal if care is taken to reapproximate the medial canthal tendon and to leave the bone over the trochlea intact. Concern about orbital contents prolapsing into the frontal recess can be assuaged by meticulously
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keeping the orbital periosteum intact and by using a laterally based flap which serves to reinforce and mucosalize the orbital periosteum. It has been argued that the Sewell-Boyden approach is useful only for unilateral disease, but this is not the case: the frontal sinus septum can be drilled down under direct visualization through the external ethmoidectomy incision. The first requirement of surgery is adequate exposure. The SewallBoyden frontoethmoidectomy offers excellent exposure to the critical portions of the frontal recess, agger nasi, superior nasal septum, and frontal sinus septum to allow routine and commonly available drills and instruments to be brought into the surgical field. Visualization is binocular, excellent, and is much less affected by bleeding than functional endoscopic sinus surgery (FESS) approaches. No endoscope or microscope is necessary. The creation of a septa1 mucosal flap should improve the overall long-term patency rate to the range of 85%,a benchmark for the relatively new endoscopic transnasal frontal sinus approaches.'8 As with any surgical technique, laboratory dissection time and solid anatomic knowledge and study are necessary to achieve success. One further cautionary point needs to be made. Perhaps the best way to avoid consideration of all frontal sinus procedures in this day of elective surgery is through prevention at the time of initial, elective functional endoscopic sinus surgery. Attention to detail during functional endoscopic ethmoidectomy should help prevent scarring in the critical frontal recess area and thereby reduce the incidence of iatrogenic chronic frontal sinusitis which can be produced if the recess becomes traumatized during surgical intervention. It is striking that in entire careers in otolaryngology in the 1950s, but also in the 1980s and 1990s, only 50 or so patients required a frontoethmoidectomy with Sewall-Boyden reconstruction.",27Furthermore, these cases occurred in the practices of surgeons who are quite facile with the technique. So, although the frontoethmoidectomy with SewallBoyden reconstruction is an excellent approach with a good track record, its indications in busy practices are actually uncommon. Its relative rarity, however, does not diminish its usefulness in the properly selected patient. SUMMARY The Sewall-Boyden frontoethmoidectomy offers excellent visualization of the frontal recess and upper nasal septum to bring commonly available instruments to bear on the frontal sinus drainage track without the need for endoscopic instrumentation. In concept, the technique is similar to the transnasal frontal sinus drillout procedures designed to preserve frontal sinus aeration in the treatment of severe frontal sinus disease, and it shares the inherent advantages of these approaches. The technique has a track record spanning more than 50 years with a long-term patency rate ranging upwards of 85%.The Sewall Boyden frontoethmoidectomy should be retained in the surgical armamentarium.
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References 1. Baron SH, Dedo HH, Henry C R The mucoperiosteal flap in frontal sinus surgery. Laryngoscope 83:12661280,1973 2. Becker DG: Modified transnasal endoscopic Lothrop procedure: Further considerations. Laryngoscope 1051161-1166,1995 3. Bent JP 111, Cuilty-SillerC, Kuhn FA The frontal cell as a cause of frontal sinus obstruction. Am J Rhinol 33185-192,1994 4. Bergara AR Osteoplastic operation on large frontal sinus in chronic suppurative sinusities: End results. Transactions of the American Academy of Ophthalmology and Otolaryngology 51:643447,1947 5. Boyden GL: Chronic frontal sinusitis: End results of surgical treatment. Transactions of the American Academy of Ophthalmology and Otolaryngology 61:588-591,1957 6. Boyden G L Surgical treatment of chronic frontal sinusitis. Ann Otol Rhinol Laryngol 61:558-566,1952 7. Braun A Sinus Thrombophlebitis, New York, Paul B. Hoeber, 1928 8. Casiano RR, Livingston J A Endoscopic Lothrop procedure: The University of Miami experience. Am J Rhinol 12335-339,1998 9. Close LG, Lee NK, Leach JL, et a 1 Endoscopic resection of the intranasal frontal sinus floor. Ann Otol Rhinol Laryngol103:952-958,1994 10. Davis WB Development and Anatomy of the Nasal Accessory Sinuses in Man. Philadelphia, WB Saunders, 1914, p 51 11. Dedo HH, Broberg TG, Murr AH: Frontoethmoidectomy with Sewall-Boydenreconstruction: Alive and well, a 25-year experience. Am J Rhinol 12:191-198,1998 12. Draf S Endonasal micro-endoscopic frontal sinus surgery: The Fulda concept. Operative Techniques in Otolaryngology-Head and Neck Surgery 2:234-240,1991 13. Goodale RL, Montgomery WW: Experiences with osteoplastic anterior wall approach to frontal sinus. Archives of Otolaryngology 68:271-283,1958 14. Gross CW, Zachmann GC, Becker DG, et al: Follow-up of University of Virginia experience with the modified Lothrop procedure. Am J Rhinol 11:49-54,1997 15. Gross WE: Modified transnasal endoscopic Lothrop procedure as an alternative to frontal sinus obliteration. Otolaryngol Head Neck Surg 113427434,1995 16. Grunewald L (Lamb W, trans): A Treatise on Nasal Suppuration. New York, William Wood, 1900 17. Hajek M (Heitger JD, Hansel FK, trans): Pathology and Treatment of the Inflammatory Diseases of the Nasal Accessory Sinuses, Vol 1.St. Louis, Mosby, 1926, pp 141-143,374379 18. Jacobs JB: 100 Years of frontal sinus surgery. Laryngoscope 107 (suppl83):1-36,1997 19. Kennedy DW Endoscopic sinus surgery for mucoceles: A viable alternative. Laryngoscope 99:885895,1989 20. Lack H L The Diseases of the Nose and its Accessory Sinuses. London, Longman, Green, 1906, p 19 21. Lawson W The intranasal ethmoidectomy: Evaluation and an assessment of the procedure. Laryngoscope 104 (suppl64):149,1994 22. Lynch RC: The technique of a radical frontal sinus operation which has given me the best results. Laryngoscope 31:l-5,1921 23. McNaught RC: A refinement of the external frontoethmosphenoid operation: A new nasofrontal pedicle flap. Arch Otolaryngol23:544-549,1936 24. Neel HB 111, McDonald TJ, Facer G W Modified Lynch procedure for chronic frontal sinus diseases: Rationale, technique, and long-term results. Laryngoscope 9712741279,1987 25. Neel HB, Whicker JH, Lake C F Thin rubber sheeting in frontal sinus surgery: Animal and clinical studies. Laryngoscope 863526536,1976 26. Ogura JH, Watson RK, Jurema AA:Frontal sinus surgery. The use of mucoperiosteal flap for reconstruction of a nasofrontal duct. Laryngoscope 70:1229-1243,1960 27. Porto DP, Duvall AJ I11 Long-term results with nasofrontal duct reconstruction. Laryngoscope 96:858-862,1986 28. Schaefer SD, Close LG: Endoscopic management of frontal sinus disease. Laryngoscope 100:155-1 60,1990
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29. Schaeffer JP: The Nose, Paranasal Sinuses, Nasolacrimal Passageways, and Olfactory Organ in Man. Philadelphia, P. Blakiston’s Son, 1920, pp 95,152 30. Sewall EC: The operative treatment of nasal sinus disease. Ann Otol Rhino1 Laryngol 44~307-316,1935 31. Turner AL: Diseases of the Nose, Throat and Ear. Bristol, John Wright and Sons, 1932, pp 95-100 32. Turner AL, Reynolds FE: Intracranial Pyogenic Diseases. London, Oliver and Boyd, 1931
Address reprint requests to Andrew H. Murr, MD Department of Otolaryngology-Head and Neck Surgery University of California San Francisco 400 Parnassus Avenue, A739 San Francisco, CA 94143 e-mail: ahmurrQorca.ucsf.edu
0030-6665/01 $15.00 + .OO
FRONTOETHMOIDECTOMY WITH SEWALL-BOYDEN RECONSTRUCTION Indications, Technique, and Philosophy Andrew H. Murr, MD, and Herbert H. Dedo, MD
This article discusses an interesting spin on an old approach to the surgical management of frontal sinus disease: frontoethmoidectomy with Sewall-Boyden flap reconstruction. The discussion emphasizes technique, because a lack of understanding of the intricacies of the technique is clearly the main impediment to widespread use of the approach. Also included are the authors' experience with the approach over many years and a discussion of indications, risks, and complications. HISTORY It is ironic that nearly all the anatomic and surgical innovations in frontal sinus surgery and the understanding of the frontal recess are more than 100 years old. Turn-of-the-century textbooks are replete with detailed anatomic and surgical descriptions of the frontal sinus and the surgical approaches to it. Hajek has exquisitely detailed anatomic descriptions of the frontal recess in the English translation of his 1926 text.17In this same textbook, an extraordinary discussion of transnasal and open surgical approaches is exhaustively reviewed with references to then-current literature which fill many pages of bibli~graphy.'~ In the United States, the great anatomist at Jefferson Medical College, J. Parsons Schaeffer, published a From the Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco School of Medicine, San Francisco, California
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textbook in 1920 that could be mistaken for a modern publication, right down to his anatomic and embryologic descriptions of the frontal recess and his actual use of the term frontal ~ecess.’~ Schaeffer also includes descriptions and illustrations of what has been recently classified as a type I F frontal recess cell, predating this new classificationby 70 years.29Interestingly, Schaeffer’s work was an expansion of a text written by Warren B. Davis, also of the Jefferson Medical College, in 1914. Davis’ text also delineates the frontal recess boundaries and discusses the structure of agger nasi cells as they relate to the uncinate process.1° It is relatively easy to understand why anatomists and physicians at the turn of the century were so interested in the frontal sinus and frontal recess. In that era before antibiotics empyema of the frontal sinus was relatively common, and fulminant acute sinusitis often led to meningitis and subsequent death. A. Logan Turner has a seemingly mundane chapter, including clinical photographs, of just such problems in his 1932 textbook Diseuses of the Eau, Nose, and Thuoat.3l In fact, authors including Turner and Reynolds,3* Grunewald,’6 and Braun7 wrote entire textbooks on septic thrombophlebitic complications.Catheterization of the frontal sinus was discussed in almost every textbook, usually in the early chapters where the more basic procedures used in everyday practice were positioned.20Obviously, this exhaustive coverage of the frontal sinus was stimulated by the frequently severe and sometimes fulminant infection of these awkwardly positioned paranasal sinus cells. With this frequency of frontal sinus infection and the possibility of devastating subsequent intracranial complication, surgeons became quite adept at interveningin an attempt to limit osteomyelitis,progressivethrombophlebitis,meningitis,brain suppuration, and death. Procedures involved two approaches: direct external drainage or transnasal drainage. The former was often accompanied by scarring at the site of incision, and the latter was often accompanied by failure to drain the infected sinus adequately or by intracranial penetration. The tendency for intracranial penetration led Harris P. Mosher to proclaim that the transnasal approach was one of the easiest ways to kill a patient.’l In both types of procedures, long-term clinical follow-up often revealed stubborn restenosis of the drainage opening. Without modern endoscopes or the luxury of computed tomographic (CT) imaging, follow-up was accomplished with plain film radiology and blind probing of the opening. The frontoethmoidectomy with Sewall reconstruction was an external approach based on the standard Lynch procedure described by Lynch in 1921= but with one major difference: there was an attempt to use a local septal mucosal flap to reconstruct the newly cleared frontal drainage t r a ~ k .The ~ ~modification ,~~ was deemed necessary because with the Lynch procedure stenosis of the neoduct was experienced approximately one third of the time.24McNaughP3and SewalPO reported the use of the septal mucosal flap in the mid-l930s, and Boyden: Ogura,26and Baron and Dedo’ resurrected the concept in the late 1950s and early 1960s. Other literature on the Lynch procedure was almost totally devoted to trying to find the perfect stent material so that the track would remain patent.25Many
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clinicians tried a great array of substances, including tantalum, polytetrafluoroethylene, silicone rubber, and red rubber, either as a tube, a roll, a stent, or a sheet. None of the variations seemed to prevent stenosis. What did seem to lessen the frequency of stenosis, however, was the mucosal flap, for which very high permanent patency rates were reported. At this time, however, the popularity of the obliterative approach, as resurrected by Bergara; and Goodale and M~ntgomery,'~ was also growing. As this obliterative approach became more popular, the Sewall-Boyden approach fell into disuse and was used by only a few surgeons. INDICATIONS There are no absolute indications for the Sewall-Boyden frontoethmoidectomy technique; rather, there are relative indications based on the type and extent of frontal sinus disease and the surgeon's preference for and comfort with a variety of available technologies. In broadest terms, the Sewall-Boyden technique should be considered for acute frontal sinusitis that is refractory to antibiotic therapy. These situations are sometimes complicated by periorbital cellulitis and abscess or anterior table cellulitis and Pott's puffy tumor. These situations are rare today with the widespread use of powerful antibiotics, but the occasional urgent case still requires surgical drainage. Other treatment options include a frontal trephination or an endoscopic approach to the frontal recess, but the Sewall-Boyden technique remains a reasonable option providing quick and direct access to the disease in what is sure to be a hyperemic and inflamed surgical field. Chronic frontal sinusitis refractory to adequate medical therapy is another relative indication for Sewall-Boyden frontoethmoidectomy. The procedure typically receives more serious consideration after endoscopic surgical approaches have failed and is often considered at the same time that frontal drillout2,'2 procedures enter the clinical algorithm. The SewallBoyden approach offers the familiarity and comfort of binocular and normal vision and the use of readily available instrumentation and drills. Most centers recommending the endoscopic Lothrop approach are equipped with special drills, microd6briders, and computerized stereotactic navigation systems. The cases requiring this type of surgery are infrequently encountered, and if specialized equipment is lacking it may be more prudent to rely on more readily and easily available instrumentation. A large frontal mucocele resting on dura is another excellent indication for the Sewall-Boyden approach. Here, the risk of leaving retained mucocele lining on the dura would be difficult to avoid and is therefore an obvious limitation of the osteoplastic obliteration approach, in which all mucosa must absolutely be removed. The Sewall-Boyden technique eliminates the need to remove the mucosal lining of the mucocele completely. The reconstruction of the frontal drainage tract allows complete marsupialization of the sinus, preventing recurrence of the mucocele. It also allows endoscopic and radiologic follow-up of the sinus; the preclusion of such follow-up is a limitation of the obliterative approach. A good alternative
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approach for a mucocele on dura is the endoscopic approach as popularized by Kennedy." Nevertheless, the Sewall-Boyden technique offers an equally functional method for marsupializing a mucocele on dura. Finally, the Sewell-Boyden frontoethmoidectomy is an alternative for addressing certain types of bone tumors such as osteomas. Here, the endoscopic approach is obviously limited in terms of access, whereas the external frontoethmoid approach offers good exposure for a drill and the Sewall mucosal flap preserves good frontal sinus drainage and aeration, eliminating the need for osteoplastic obliteration. TECHNIQUE
The surgical technique" for frontoethmoidectomywith Sewall-Boyden reconstruction is familiar to most surgeons who have been schooled in the technique of external frontoethmoidectomy.The Sewell-Boyden modification simply adds a mucosal rotational flap from the dorsum of the nose which relines the frontal recess, rather than relying on a stent or tube to attempt to force scar tissue to reline the recess (Fig. 1A and B). The procedure is conducted under general anesthesia. A tarsorrhaphy stitch or corneal shield is placed in the usual fashion. An external ethmoidectomy incision is outlined midway between the medial canthus and the nasion. The incision is brought to the medial tip of the eyebrow and to the bottom of the nasal pyramid, but it does not need to extend to the level of the nostril (Fig. 2 4 . It can be helpful to include a running W-plasty in the incision to prevent webbing and shortening of the future scar. Branches of the angular artery are encountered just beneath the skin,
Figure 1. A, Sagittal view of flap location on septum. 6,Frontal view of lateral Sewall-Boyden flap in place. (FromDedo HH, Broberg TA, Murr AH: Frontoethmoidectomywith Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
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Figure 2. A, Incision only to inferior medial edge of eyebrow. 6,Area of bone removal: lateral nasal bone and over anterior inferior frontal sinus. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 123, 1998; with permission.)
and care should be taken to identify and ligate the vessels securely or to use a bipolar cautery on them individually. If they are not arrested properly, they can obscure the field with blood throughout the procedure. The incision is brought down to periosteum which is divided with #15 blade. Using a Cottle elevator in one hand and a Frazier suction in the other, the surgeon raises the periosteum back to the level of the anterior ethmoid artery along the frontoethmoid suture line. This suture line delineates the approximate level of the skull base, and the anterior ethmoid artery delineates the level where the fovea ethmoidalis begins its rise to become the back wall of the frontal sinus. A hemaclip is placed on the anterior ethmoid artery. The lacrimal sac is retracted laterally but not incised, and the orbital periosteum and its contents are retracted with a Sewall retractor. The trochlea may be elevated with the orbital periosteal contents in continuity. An external ethmoidectomy is accomplished in the usual fashion, beginning by entering the ethmoid cavity in the lacrimal sac fossa and working posteriorly to the sphenoid and anteriorly into the frontal sinus. An otologic drill is used to outline a roughly rectangular nasal bony plate that is then removed. Grooves are made with a small rotating cutting burr down to the level of the internal nasal mucoperiostium (Fig. 2 B ) . This bone rectangle includes the nasal bone, nasal process of the frontal bone, and the nasal process of the maxilla. The bone plate is elevated with technique similar to that used for elevating a retrosigmoid bone flap in neurotologic surgery (Fig. 3). This procedure exposes the nasal mucosa of the upper nasal vault, the area where osteotomies in rhinoplasty are usually cut with a medially and laterally placed osteotome.
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Figure 3. Lateral nasal pyramid bony plate removal to expose flap. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction:Alive and well, a 25 year experience. American Journal of Rhinology 12:3,1998; with permission.)
The delta area or nasal beak is then drilled under direct visualization with a diamond or cutting otologic burr to the plane of the septum (Fig. 4). A Cottle elevator is used to elevate the septal mucosal flap off the perpendicular plate of the ethmoid and quadrangular cartilage (Fig. 5 ) . Two perpendicular cuts are made (designated A and B in Figure 6 ) . A fair amount of bleeding results from these cuts. A third parallel cut is made (designated C in Figure 7) which allows the septal mucosal flap to be swung up against the orbital periosteum and into the frontal sinus (Fig. 8A and B ) . The flap can then be secured with one or two 4-0 plain gut tacking sutures to the orbital periosteum (Fig. 9). If desired, a stent or 14-French red rubber catheter can be placed to hold the flap gently in position for 7 or 10 days. The timing of the stent placement is variable. The incisionis closed in a routine, careful fashion with special attention paid to reconstituting the medial canthal tendon attachment. The skin is usually closed with a 6-0 nylon, or a subcuticular type suture may be used. A drain is not placed, but a nasal pack may be placed if needed.
RESULTS The experience on which this article is based is a 25-year surgical practice. The results were published in 1998 in The American Journal of Rhinology." Forty-one patients were reviewed, encompassing 25 years of
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Figure 4. Removal of delta area. Frontal sinus and nasal mucosa is exposed. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
Figure 5. Entering frontal sinus with creation of microflap, and elevating nasal mucosa off upper septum. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with SewallBoyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
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Figure 6. Making posterior Sewall incision in septa1 and lateral nasal mucosa (Cut A). (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomywith Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
practice from 1970 to 1995. Thirty-six of the 41 who had adequate records for the purposes of documentation were included in the review. Follow-up ranged from 2 months to 24 years and 8 months. The nasofrontal track remained open in 35 of 36 patients in this report. One patient with aspergillosis for whom surgery was not initially successful had successful revision surgery. Twenty patients had either postoperative CT scans (13) or plain
Figure 7. Anterior incision in nasal rnucosa (Cut 6). (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectorny with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3, 1998; with permission.)
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Figure 8. A, Cut C betweenends of A and B on septa1 mucosa alone has freed Sewall-Boyden flap. B, Flap based on lateral nasal wall with free end rotating up into frontal sinus. (FromDedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction: Alive and well, a 25 year experience. American Journal of Rhinology 12:3;1998; with permission.)
film radiographs (7),and 85% (17 of 20) of these demonstrated aeration of the frontal sinus. In two patients, polyps requiring further removal caused the lack of aeration. The other patient had an interval infection which cleared with antibiotic therapy. This report indicates that the technique of mucosal flap reconstruction after frontoethmoidectomy is more successful than using stents or tubes alone. This finding is no surprise. Boyden
Figure 9. Laterally based flap in place with upper end extending to the floor of the frontal sinus. (From Dedo HH, Broberg TA, Murr AH: Frontoethmoidectomy with Sewall-Boyden reconstruction:Alive and well, a 25 year experience.American Journal of Rhinology 12:3,1998; with permission.)
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reported a 100% symptom-free rate over a 17-year period using the technique in 57 patient^.^ In 1960, Ogura reported success in 19 of 20 patients.26 More recently, Porto reviewed 50 cases with long-term follow-up and reported an 86% success rate.27
DISCUSSION With the demonstrated success of the Sewall-Boydentechnique firmly reported in the literature, why do so few surgeons embrace the procedure? The lack of enthusiasm for it is based first on the difficulty in visualizing exactly where the flap is created. The location is difficult to diagram and difficult to learn from drawings, because the location of the flap is not intuitive. The flap technique is nevertheless easy to practice in the anatomy laboratory and to teach in the operating room. The attempt to avoid obliterating the frontal sinus and to create a functional drainage track is quite in vogue of late. The advantages of a functioning sinus include the ability to follow the sinus radiologically in the future, and the ability to examine the sinus in the office setting with rigid or flexible scopes. Preservation of a functioning sinus can also be helpful when it would be difficult to exenterate the frontal sinus mucosa completely, as when a mucocele rests on dura or when there is extensive supraorbital pneumatization. Problems with osteoplastic obliteration can also arise many years after surgery and therefore require very extensive follow-up. Because of this potential for postoperative mucocele formation and postoperative infection many years after the original surgery, many surgeons argue that transnasal frontal sinus preservation is often better than obliteration by an osteoplastic approach. Reports of transnasal frontal sinus marsupialization abound in the literature. Techniques have been l5 Draf,” Casiano; Jacobs,’s and other^.^ reported by Schaefer,2s Enthusiasm has built for an endoscopic Lothrop approach to the frontal sinus whereby the top of the nasal septum is drilled away to approach the frontal sinus septum: excellent, though short-term, results have been reported with regard to patency? l4 The Sewall-Boyden frontoethmoidectomy is conceptually equivalent to these endoscopic approaches except that it is accomplished by a small external ethmoidectomy incision. It has all the advantages of these endoscopic approaches in preserving function and has the further advantages of relative technical simplicity, excellent exposure of the external ethmoidectomy approach, and the ability to create a septa1 mucosal flap to line the frontal recess. Certainly, the longterm follow-up of the technique has been well established during the last 50 years. Disadvantages of the Sewall-Boyden technique include the external scar in the medial canthal region. In most patients the scar can be cosmetically well hidden. Concerns about diplopia are valid, but problems should be minimal if care is taken to reapproximate the medial canthal tendon and to leave the bone over the trochlea intact. Concern about orbital contents prolapsing into the frontal recess can be assuaged by meticulously
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keeping the orbital periosteum intact and by using a laterally based flap which serves to reinforce and mucosalize the orbital periosteum. It has been argued that the Sewell-Boyden approach is useful only for unilateral disease, but this is not the case: the frontal sinus septum can be drilled down under direct visualization through the external ethmoidectomy incision. The first requirement of surgery is adequate exposure. The SewallBoyden frontoethmoidectomy offers excellent exposure to the critical portions of the frontal recess, agger nasi, superior nasal septum, and frontal sinus septum to allow routine and commonly available drills and instruments to be brought into the surgical field. Visualization is binocular, excellent, and is much less affected by bleeding than functional endoscopic sinus surgery (FESS) approaches. No endoscope or microscope is necessary. The creation of a septa1 mucosal flap should improve the overall long-term patency rate to the range of 85%,a benchmark for the relatively new endoscopic transnasal frontal sinus approaches.'8 As with any surgical technique, laboratory dissection time and solid anatomic knowledge and study are necessary to achieve success. One further cautionary point needs to be made. Perhaps the best way to avoid consideration of all frontal sinus procedures in this day of elective surgery is through prevention at the time of initial, elective functional endoscopic sinus surgery. Attention to detail during functional endoscopic ethmoidectomy should help prevent scarring in the critical frontal recess area and thereby reduce the incidence of iatrogenic chronic frontal sinusitis which can be produced if the recess becomes traumatized during surgical intervention. It is striking that in entire careers in otolaryngology in the 1950s, but also in the 1980s and 1990s, only 50 or so patients required a frontoethmoidectomy with Sewall-Boyden reconstruction.",27Furthermore, these cases occurred in the practices of surgeons who are quite facile with the technique. So, although the frontoethmoidectomy with SewallBoyden reconstruction is an excellent approach with a good track record, its indications in busy practices are actually uncommon. Its relative rarity, however, does not diminish its usefulness in the properly selected patient. SUMMARY The Sewall-Boyden frontoethmoidectomy offers excellent visualization of the frontal recess and upper nasal septum to bring commonly available instruments to bear on the frontal sinus drainage track without the need for endoscopic instrumentation. In concept, the technique is similar to the transnasal frontal sinus drillout procedures designed to preserve frontal sinus aeration in the treatment of severe frontal sinus disease, and it shares the inherent advantages of these approaches. The technique has a track record spanning more than 50 years with a long-term patency rate ranging upwards of 85%.The Sewall Boyden frontoethmoidectomy should be retained in the surgical armamentarium.
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References 1. Baron SH, Dedo HH, Henry C R The mucoperiosteal flap in frontal sinus surgery. Laryngoscope 83:12661280,1973 2. Becker DG: Modified transnasal endoscopic Lothrop procedure: Further considerations. Laryngoscope 1051161-1166,1995 3. Bent JP 111, Cuilty-SillerC, Kuhn FA The frontal cell as a cause of frontal sinus obstruction. Am J Rhinol 33185-192,1994 4. Bergara AR Osteoplastic operation on large frontal sinus in chronic suppurative sinusities: End results. Transactions of the American Academy of Ophthalmology and Otolaryngology 51:643447,1947 5. Boyden GL: Chronic frontal sinusitis: End results of surgical treatment. Transactions of the American Academy of Ophthalmology and Otolaryngology 61:588-591,1957 6. Boyden G L Surgical treatment of chronic frontal sinusitis. Ann Otol Rhinol Laryngol 61:558-566,1952 7. Braun A Sinus Thrombophlebitis, New York, Paul B. Hoeber, 1928 8. Casiano RR, Livingston J A Endoscopic Lothrop procedure: The University of Miami experience. Am J Rhinol 12335-339,1998 9. Close LG, Lee NK, Leach JL, et a 1 Endoscopic resection of the intranasal frontal sinus floor. Ann Otol Rhinol Laryngol103:952-958,1994 10. Davis WB Development and Anatomy of the Nasal Accessory Sinuses in Man. Philadelphia, WB Saunders, 1914, p 51 11. Dedo HH, Broberg TG, Murr AH: Frontoethmoidectomy with Sewall-Boydenreconstruction: Alive and well, a 25-year experience. Am J Rhinol 12:191-198,1998 12. Draf S Endonasal micro-endoscopic frontal sinus surgery: The Fulda concept. Operative Techniques in Otolaryngology-Head and Neck Surgery 2:234-240,1991 13. Goodale RL, Montgomery WW: Experiences with osteoplastic anterior wall approach to frontal sinus. Archives of Otolaryngology 68:271-283,1958 14. Gross CW, Zachmann GC, Becker DG, et al: Follow-up of University of Virginia experience with the modified Lothrop procedure. Am J Rhinol 11:49-54,1997 15. Gross WE: Modified transnasal endoscopic Lothrop procedure as an alternative to frontal sinus obliteration. Otolaryngol Head Neck Surg 113427434,1995 16. Grunewald L (Lamb W, trans): A Treatise on Nasal Suppuration. New York, William Wood, 1900 17. Hajek M (Heitger JD, Hansel FK, trans): Pathology and Treatment of the Inflammatory Diseases of the Nasal Accessory Sinuses, Vol 1.St. Louis, Mosby, 1926, pp 141-143,374379 18. Jacobs JB: 100 Years of frontal sinus surgery. Laryngoscope 107 (suppl83):1-36,1997 19. Kennedy DW Endoscopic sinus surgery for mucoceles: A viable alternative. Laryngoscope 99:885895,1989 20. Lack H L The Diseases of the Nose and its Accessory Sinuses. London, Longman, Green, 1906, p 19 21. Lawson W The intranasal ethmoidectomy: Evaluation and an assessment of the procedure. Laryngoscope 104 (suppl64):149,1994 22. Lynch RC: The technique of a radical frontal sinus operation which has given me the best results. Laryngoscope 31:l-5,1921 23. McNaught RC: A refinement of the external frontoethmosphenoid operation: A new nasofrontal pedicle flap. Arch Otolaryngol23:544-549,1936 24. Neel HB 111, McDonald TJ, Facer G W Modified Lynch procedure for chronic frontal sinus diseases: Rationale, technique, and long-term results. Laryngoscope 9712741279,1987 25. Neel HB, Whicker JH, Lake C F Thin rubber sheeting in frontal sinus surgery: Animal and clinical studies. Laryngoscope 863526536,1976 26. Ogura JH, Watson RK, Jurema AA:Frontal sinus surgery. The use of mucoperiosteal flap for reconstruction of a nasofrontal duct. Laryngoscope 70:1229-1243,1960 27. Porto DP, Duvall AJ I11 Long-term results with nasofrontal duct reconstruction. Laryngoscope 96:858-862,1986 28. Schaefer SD, Close LG: Endoscopic management of frontal sinus disease. Laryngoscope 100:155-1 60,1990
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29. Schaeffer JP: The Nose, Paranasal Sinuses, Nasolacrimal Passageways, and Olfactory Organ in Man. Philadelphia, P. Blakiston’s Son, 1920, pp 95,152 30. Sewall EC: The operative treatment of nasal sinus disease. Ann Otol Rhino1 Laryngol 44~307-316,1935 31. Turner AL: Diseases of the Nose, Throat and Ear. Bristol, John Wright and Sons, 1932, pp 95-100 32. Turner AL, Reynolds FE: Intracranial Pyogenic Diseases. London, Oliver and Boyd, 1931
Address reprint requests to Andrew H. Murr, MD Department of Otolaryngology-Head and Neck Surgery University of California San Francisco 400 Parnassus Avenue, A739 San Francisco, CA 94143 e-mail: ahmurrQorca.ucsf.edu