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Retrograde Mastoidectomy
Otolaryngol Clin N Am 39 (2006) 1115–1127
Retrograde Mastoidectomy John L. Dornhoffer, MDa,b,c,* a
Division of Neurotology, Department of Otolaryngology/Head and Neck Surgery, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 543 Little Rock, AR 72205, USA b ENT Clinic and Audiology Services, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 543 Little Rock, AR 72205, USA c Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 543 Little Rock, AR 72205, USA
After nearly 5 decades of debate, the management of the posterior canal wall in cholesteatoma surgery remains a controversial issue. The canal wall up (CWU) tympanomastoidectomy preserves the normal anatomy of the ear canal, thus avoiding the risk of bowl problems and the necessity for periodic cleaning and leading to reduced healing time and, possibly, better hearing results [1]. Likewise, one must consider that surgery for cholesteatoma, which frequently involves complex ossicular reconstruction, may require hearing rehabilitation, with the need for amplification postoperatively. Hearing aid fitting after CWU surgery is generally straightforward and associated with fewer complications than that after canal wall down (CWD) tympanomastoidectomy. However, a high recitative rate (cholesteatoma left behind) and recurrence rate (recurrent retractions leading to cholesteatoma formation) continue to be major drawbacks to CWU surgery. At issue is the exposure of the critical anatomic regions for cholesteatoma removal: the epitympanum and associated supratubal recess and the mesotympanum. These are the two areas associated with most recurrent disease [2]. Primary acquired cholesteatomas typically begin as retraction pockets in the pars flaccida (epitympanic cholesteatoma) or posterior pars tensa (mesotympanic cholesteatoma). In the former situation, the sac typically forms in Prussak’s space, lateral to the malleus, and exits posteriorly or inferiorly, with some evidence of erosion of the scutum. The sac typically egresses lateral to the body of the incus into the antrum. With larger epitympanic cholesteatomas, one should anticipate extensive involvement of the epitympanic space and supratubal recess. The sinus tympani and facial recess can also be problematic, but are involved secondarily through inferior extension of the * Corresponding author. E-mail address: [email protected] 0030-6665/06/$ - see front matter Ó 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.otc.2006.08.002
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cholesteatoma into the mesotympanum. Mesotympanic cholesteatomas, on the other hand, arise from posterior retraction of the pars tensa and extend toward the antrum medial to the incus. In these cases, involvement of the sinus tympani and facial recess is very frequent, with extension to the epitympanum between the facial nerve and incus. CWU surgery, especially in cases with poorly developed zygomatic root cells and a low tegmun, can provide very limited exposure of the epitympanum and posterior mesotympanum, leading to blind and piecemeal removal of the cholesteatoma, which contributes to the high recitative rate. Frequently, the surgeon believes that the anterior epitympanic space has been reached, while in actuality only the bony cog has been exposed and disease is still present in the supratubal recess. Because of these short comings, second-stage surgery is frequently recommended 9 to 12 months after the initial CWU tympanomastoidectomy [3–5]. A review of the literature shows a wide variation in the reported recurrence rates with this technique. Sheehy and Robinson [6] initially reported recurrence rates of 5%, whereas Glasscock [7] reported a 14% recurrence rate. Recurrence rates up to 20% to 40% have also been reported [3,4]. As pointed out so aptly by Smyth [2], long-term results with CWU cholesteatoma can be very humbling, with recurrence rates of between 15% and 50%, even after staging. Nyrop and Bonding’s 10-year follow-up of CWU cases in Copenhagen showed that 70% required a later CWD surgery [8]. The CWD technique creates an open cavity after removal of the bony posterior canal wall, providing excellent exposure for cholesteatoma removal. The epitympanum, cog, and supratubal recess are widely exposed, facilitating complete removal of the cholesteatoma sac and lowering the recurrence rate to 5% to 10% [9,10]. Taking the canal wall down to the level of the facial ridge deals adequately with facial recess disease and affords improved, but by no means complete, view of the sinus tympani. In cases without sinus tympani involvement, this technique can also frequently be performed as a single-stage surgery. The main disadvantages of this technique are related to the necessity for periodic cleaning of the mastoid cavity [9,10]. Subsequent bowl infections can occur, especially when the cavity becomes wet, causing significant lifestyle changes, particularly in the pediatric age group [9]. In addition, the hearing results are frequently worse due to the shallow middle ear cleft [9,10]. Although bone-anchored hearing aids and open-mold technology have offered some new possibilities for amplification in this group, traditional hearing aid fitting can be very problematic due to a wet cavity, or widened, distorted meatus. Evolution of retrograde tympanomastoidectomy with canal reconstruction There has been a trend toward the development of surgical techniques that involve temporary removal of the canal wall, offering the exposure of CWD surgery for cholesteatoma extirpation, followed by reconstitution of the canal
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wall defect using autologous (bone, cartilage) or alloplastic (hydroxyapatite cement, titanium) graft materials [11–17]. The retrograde tympanomastoidectomy is one such technique that involves temporary removal of the upper canal wall, in association with a retrograde-type mastoidectomy, followed by reconstruction of the canal defect using Cymba cartilage. The posterior tympanic membrane is reconstructed with the cartilage palisade technique in close approximation with the canal reconstruction to inhibit recurrent retractions. Our 15-year experience with this technique has shown that the exposure of the epitympanum and upper mesotympanum is similar to CWD surgery, allowing single-stage surgery in 90% of cases, with 10-year recurrence rates very similar to those reported for CWD surgery. The primary indication for second-look or staged surgery is involvement of the sinus tympani with uncertain removal, which continues to be a difficulty with all techniques. Primary reconstruction of the ossicular chain is done in all cases, regardless of the need for a planned second surgery, as it acts as a scaffolding for the primary reconstruction. Before a detailed description of this technique is provided, it is worthwhile to consider its evolution. Conceptually, this technique seems to resemble an extended atticotomy; however, it actually represents a union of two divergent approaches: the osteoplastic flap of Wu¨llstein [14] and the small-cavity technique of Smyth [2]. Wu¨llstein recognized the advantage of this concept when he described osteoplastic flap surgery in 1974 [14]. A traditional CWU surgery was performed, followed by removal of the canal wall for exposure of the epitympanum, with subsequent reinsertion of the bony segment after cholesteatoma extirpation. Others have modified this technique by rigidly fixing the canal remnant with microplates and frequently using a vascularized pedicled flap for coverage [17]. Good preliminary results have been reported with these modifications [17]. However, the problem of a technically challenging fit, coupled with late bony necrosis of the reinserted graft, limited the routine acceptance of this technique [13]. Likewise, we have found that after the bony segment was removed, it was often necessary to drill anteriorly to further expose the supratubal recess, resulting in the bony segment becoming too small to be reused. Smyth’s small cavity surgery, on the other hand, described a technique that involved a CWD surgery by starting from the canal side, gradually enlarging it until complete exposure of the cholesteatoma was accomplished. This ended up creating a much smaller cavity than traditional CWD techniques, which involve a complete mastoidectomy, skeletonizing the sigmoid sinus and tegmen, and removing the canal wall when deemed necessary. With Smyth’s technique, it was found that when the mastoid was sclerotic, as is often the case with adult cholesteatomas, the cholesteatoma extended only to the antrum, resulting in a very small cavity. Professor Jan Helms, who succeeded Wu¨llstein at the University of Wu¨rzburg, performed an approach similar to Smyth’s, starting with a posterior canaloplasty and widening the canal until the air cells were first visible
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through the bone. The drilling then turned superiorly, skeletonizing the tegmun to the anterior malleolar ligament and following the cholesteatoma posteriorly into the antrum. The cholesteatoma frequently extended just to the antrum, in which case the canal wall defect was reconstructed with cartilage from the conchal bowl. The defect was typically small enough that the cartilage was supported superiorly at the zygomatic buttress, inferiorly at the posterior canal wall, and laterally at the mastoid cortex. If the cholesteatoma was more extensive, ‘‘turning the corner’’ into the mastoid tip, the canal could be taken down as described by Smyth [2]. This author has modified the technique to suit the large number of pediatric patients with cholesteatoma seen in his practice. These young patients tend to have larger cholesteatomas in more developed mastoids, requiring CWD surgery using the technique of Helms. This technique was then slightly modified to allow the cholesteatoma to be followed posteriorly, but if the disease ‘‘turned the corner’’ invading the mastoid tip, it was possible to follow the disease while leaving the lower two thirds of the posterior canal wall intact. This resulted in the need to perform more extensive grooving at the zygomatic buttress as well as the posterior canal wall to facilitate a cartilage reconstruction that would be supported only superiorly and inferiorly. This results in an optimized technique for cholesteatoma removal that represents the best of what the CWU and CWD procedures have to offer. It is described in detail below.
Surgical technique Cholesteatoma removal The mastoid cortex is widely exposed through a traditional postauricular skin incision. A tympanomeatal flap is then developed, and the middle ear is entered inferiorly, away from the cholesteatoma, to determine the extent of disease in the middle ear. As this technique involves extensive drilling in close proximity and just lateral to the head of the malleus and the body of the incus, it is necessary to visualize the incudostapedial joint and the integrity of the lenticular process of the incus as an initial step. Except in cases of very limited retraction pockets, the incudostapedial joint is disarticulated to avoid trauma to the inner ear from the subsequent drilling. A canaloplasty is performed posteriorly until air cells can just be visualized through the intact cortical bone of the ear canal. This improves the view of the posterior mesotympanum in cases of mesotympanic cholesteatomas and facilitates subsequent drilling of the upper canal wall as the cholesteatoma is followed up and back into the epitympanum and antrum. A prominent tympanosquamous suture and spine are taken off at this point to increase exposure of the pars flaccida. The drilling for cholesteatoma removal begins on the canal side with a 3 mm to 4 mm cutting burr at the upper posterior quadrant of the posterior
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canal wall, leaving a thin layer of bone at the scutum to protect the neck of the cholesteatoma, which is removed later with a diamond bur. This drilling differs from a traditional atticotomy in that it extends all the way to the lateral external canal as a groove, with exposure of the tegmun tympani. Anatomic landmarks that can be used for extent of canal wall removal would be the area between the anterior malleolar spine and, inferiorly, the approximate exit of the chorda tympani from the bone (9 o’clock to 1 o’clock in a right ear.) There are two important points to keep in mind during this portion of the drilling. One is that if more than 30% of the canal wall is removed, reconstruction becomes difficult. The most common mistake is to initiate drilling at too low a point relative to the anterior malleolar spine, underestimating the extent of anterior superior involvement. Subsequent drilling to expose the supratubal recess then leaves a larger canal wall defect than initially expected. It is always better to initiate this drilling high at the anterior malleolar spine, as approximated by the short process of the malleus. The other important point is that the tegmen at the lateral external canal frequently is more inferior than the more medial tegmen at the level of the epitympanum, so care must be taken to avoid injury to the dura laterally. While preoperative CT is not routinely performed, it can help predict the height of the tegmen on the coronal view; thus, its use may be advisable for those uninitiated with this technique. As bone removal continues posteriorly, the antrum is opened and the extent of the cholesteatoma can be appreciated. The goal is to remove only the bone necessary to expose the back edge of the sac, and a complete mastoidectomy is not necessary. With a small cholesteatoma in a sclerotic mastoid, the surgeon may frequently find the cholesteatoma extends only to the antrum, so minimal drilling is needed. The sac is followed back as posteriorly as necessary until normal air cell or cholesterol granuloma is encountered behind the sac. This technique differs from that described by Tos [18], in which a small cavity is created should extensive cholesteatoma be encountered. Instead, we follow the sac toward the mastoid tip, referred to as ‘‘turning the corner,’’ leaving the lower two thirds of the canal wall intact to facilitate reconstruction. This modification allows the removal of extensive cholesteatoma in a well-aerated mastoid, as frequently found in children, thus avoiding a CWD situation (Fig. 1). The diamond burr is then used to remove the thin bone over the cholesteatoma sac, taking extreme care not to violate the sac. The posterior edge of the sac is then identified, and this is dissected upward out of the mastoid cavity, following a posterior-to-anterior direction. This allows visualization of any fistula of the bony labyrinth (horizontal semicircular canal). When the mastoid portion of the cholesteatoma has been dissected free, the incus is removed, followed by the head of the malleus, to complete the exposure. At this point, the sac remains intact, and its neck entering the retraction in the tympanic membrane can be visualized and resected from this area, leaving a small defect in the tympanic membrane (Fig. 2).
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Fig. 1. Cholesteatoma is followed back posteriorly with exposure of entire sac at its origin from the tympanic membrane.
The exposure for cholesteatoma removal is very similar to a CWD situation and allows a nice progression of disease removal, with direct visualization of the horizontal canal, facial nerve, and oval window/stapes area. If necessary, one can drill the cog to follow disease in the supratubal recess. If disease extends anteriorly into the tubal orifice, it is possible to gain increased exposure by cutting the tensor tympani tendon. If possible, the tendon is left intact to facilitate and secure the ossicular reconstruction. Reconstruction Although removal of the cholesteatoma is important to reduce residual disease, reconstruction is equally important to prevent recurrence of
Fig. 2. Sac is resected, including the incus and head of malleus.
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retraction pockets. Primary ossicular reconstruction is performed in all ears, even when second-look surgery is planned, because the prosthesis acts as a scaffolding to support the cartilage reconstruction of the tympanic membrane and maintain the middle ear space during the healing phase. To reconstruct the canal wall, a 1 mm to 2 mm diamond burr is used to form grooves in the bone at the tegmen superiorly and in the inferior canal wall. The superior groove at the zygomatic root is very important and must be drilled properly to insure a good fit. The groove should be 1 mm to 2 mm wide and 2 mm deep and should be oriented parallel to the inferior canal to avoid torsion of the graft. Medially, the groove and subsequent reconstruction should extend down to and just posterior to the anterior malleolar spine and ligament so that is will approximate the cut edge of the malleus precisely. The inferior groove should be drilled carefully as the canal is frequently thin due to a combination of the canaloplasty and subsequent mastoidectomy. Often, a shelf, as opposed to a groove, is drilled here. Although we have experimented with other materials, autologous cartilage appears to be the ideal material for canal wall reconstruction. A piece of cartilage is harvested from the cymba of the conchal bowl to reconstruct the posterior canal wall. Because of its appropriate curvature, cartilage from the cymba is ideal for this purpose, and it generally has a uniform thickness of 1 mm. Generally, the cartilage will be 1 mm to 2 mm wider than the bony defect, allowing the canal wall reconstruction to snap into place under a little tension. The medial fit of the canal wall reconstruction is the most critical, and it is essential that a good fit between the cartilage and the residual bony canal wall be achieved and that the superior edge of the cartilage reconstruction be placed medially so that it closely approximates the handle of the malleus (Fig. 3). For ossicular reconstruction, we typically use hydroxyapatite prostheses and attempt to use the malleus in the reconstruction. It has been shown that incorporation of the malleus in ossicular reconstruction provides an acoustic gain, possibly due to its cantenary action in the tympanic membrane [19].
Fig. 3. Canal wall defect reconstructed with Cymba cartilage, with close proximity to the cut edge of the manubrium.
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Likewise, the presence of the malleus with an intact anterior malleolar ligament offers improved prosthesis stability by allowing precise length adjustments and ultimate fit, leading to optimal hearing results [20]. When the malleus handle and suspensory ligaments are present, we have found that a partial ossicular replacement prosthesis (PORP), which is 2 mm in length, and a total ossicular replacement prosthesis (TORP), cut to 4.0 mm to 4.5 mm, can be consistently used for precise reconstruction when the notch of the prosthesis is placed just inferior to the insertion of the tensor tympani (Fig. 4A and B). After precise ossicular reconstruction is performed, the posterior half of the tympanic membrane is reconstructed with pieces of cartilage using the modified palisade technique. With this technique, the tympanic membrane is put together like a jigsaw puzzle: the half moon-shaped piece is placed on top of the prosthesis first, abutting the malleus handle, followed by the scutum piece; any spaces left between these two plates and the canal wall are reconstructed with slivers of cartilage cut to fit precisely in these areas (Fig. 5A and B). The trifurcation of the malleus handle, canal reconstruction, and tympanic membrane reconstruction has proven to be critical for recurrence prevention, so small chips of cartilage are very important in this area. Likewise, if the drilling proceeds superior to the anterior malleolar ligament, care should be taken to reinforce this small area with cartilage. The reconstruction is then covered with perichondrium or fascia and the tympanic membrane remnant, if available. No space is left between the canal wall and reconstructed tympanic membrane to prevent cholesteatoma or retraction pocket recurrence. The anterior half of the tympanic membrane is typically not reconstructed with cartilage to allow postoperative surveillance and tube insertion, if necessary.
Fig. 4. (A) Schematic showing reconstruction of the ossicular chain after canal reconstruction. (B) Interoperative picture demonstrating reconstruction.
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Fig. 5. (A) Schematic showing reconstruction of the posterior tympanic membrane with the palisade technique. (B) Interoperative picture demonstrating precise fit between palisade reconstruction of the tympanic membrane and canal wall reconstruction.
The canal is then packed with antibiotic ointment, and a Pope Otowick (Xomed Co., Jacksonville, Florida) is placed in the ear canal. The packing is removed 10 days postsurgery, and the patient is instructed to perform the Valsalva maneuver three times a day, starting 2 weeks after the surgery. The Otovent (Abigo Medical, Sweden) has been used in children who are unable to perform this maneuver. The first postoperative audiogram is obtained 6 to 8 weeks postsurgery. If the patient is unable to perform the Valsalva maneuver or if the postoperative period is complicated by an effusion or retraction of the reconstructed tympanic membrane, a ventilation tube is placed 3 to 4 months after the surgery. Primary ventilation tube insertion is generally avoided. For the most part, the retrograde mastoidectomy allows removal of the cholesteatoma sac in one piece, with direct exposure, so second-look surgery is only performed in those cases where the cholesteatoma sac was violated and had to be removed piecemeal. The area of the sinus tympani is the most problematic region, as exposure here is difficult even with the retrograde mastoidectomy. Results with the retrograde mastoidectomy As of this writing, the retrograde technique has been used at our institution as the primary surgery for cholesteatoma removal for 13 consecutive years, resulting in an experience with over 400 ears. Short-term (2-year) and longer-term (8-year) results have been reported [21,22], indicating a dramatic reduction in recurrence rates and in need for a second surgery compared with our experience with CWU surgery [23]. We no longer perform CWD surgery as a primary surgery unless more than 50% of the canal wall is destroyed by disease or exterioration is needed because of large labyrinthine or cochlear fistulae, where the matrix cannot be safely removed. In our longer term study [22], we examined the results of 46 patients (representing 50 ears undergoing this procedure) who had an average 7-year follow-up. Second-look surgery was performed in 4% for questionable
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incomplete removal of disease in the sinus tympani or footplate area. One of these patients had residual disease at the footplate. We found recurrent cholesteatoma in eight ears (six adult and two pediatric), representing a recurrence rate of 16%. The site of the original cholesteatoma was evenly divided between the epitympanum and the mesotympanum. However, of the recurrent cholesteatomas, 63% had originally been mesotympanic and 37% had originally been epitympanic, suggesting a higher recurrence rate for mesotympanic cholesteatomas. This finding is not totally unexpected. The exposure of the epitympanum and supratubal recess is superior to the standard CWU approaches, and the removal is quite direct. The reason some ears develop epitympanic disease as opposed to mesotympanic cholesteatomas in the first place, from seemingly the same pathophysiologic mechanism (ie, Eustachian tube dysfunction), is unknown. It is possible that mesotympanic cholesteatomas result from more pervasive Eustachian tube dysfunction compared with epitympanic cholesteatomas, the latter of which may reflect anatomic or structural blockage of the antrum, which could be more easily corrected with surgical removal of the disease. Likewise, it appears that a ‘‘stable retraction’’ after cholesteatoma surgery may be an oxymoron. Both of the ears noted to have stable epitympanic retractions at the short-term assessment eventually developed cholesteatomas at longer follow-up. Thus, earlier or more aggressive intubation may need to be performed in those ears with early signs of retraction. The site of recurrence after reconstruction was typically in the epitympanic area (six of eight ears), just above the malleus handle, between the canal wall reconstruction and the tympanic membrane reconstruction. All six of these eight ears were revised, with removal of the previously inserted canal wall cartilage to expose the recurrent retraction, removal of the retraction, and reinsertion of the canal wall with reinforcement of the epitympanum. This recurrence pattern points out a relative weakness of the retrograde technique. Removal of the canal wall allows excellent exposure for complete removal of the cholesteatoma, leading to very low incidence of residual disease with a single-stage approach like CWD surgery. However, the reconstruction of the canal wall and posterior tympanic membrane is challenging, with a definite learning curve. Most of the recurrences in this series (four) were noted during the initial 2-year follow-up, and the area between the canal wall and tympanic membrane cartilage reconstruction was identified as a high-risk site. Because of this, much greater care is now taken to reinforce this area with chips of cartilage (Fig. 6). The effect of this modification is felt to be positive, but longer follow-up will be important in this cohort of patients. The negative impact of smoking on long-term results was apparent in our follow-up study [22] and has changed the way we counsel and treat patients who are smokers. If one includes as complications the presence of recurrent disease, need to intubate the ear postoperatively, occurrence of a perforation,
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Fig. 6. Postoperative picture after the retrograde technique. Area in ellipse demonstrates ‘‘high-risk’’ area reinforced with additional pieces of cartilage.
and need for a second-look surgery due to poor hearing results, the longterm complication rate of smokers was 79% (15/19 ears), compared with 16% (5/31 ears) for nonsmokers, making overall complications in smokers five times that seen in nonsmokers. Postoperative intubation for persistent effusion was necessary in nine individuals in this study, of which seven were smokers. Tobacco use has been reported to have a negative impact on graft take and hearing results during tympanoplasty [24], but its effect on long-term cholesteatoma recurrence has not been reported until recently. All but two of the recurrent cholesteatomas in our series were in individuals who routinely smoked cigarettes, making cholesteatoma recurrence almost five times higher for individuals who used tobacco. Long-term hearing results with the retrograde mastoidectomy technique have been encouraging, and compare favorably with those reported in staged ossiculoplasty [7]. In our longer term study, there was a slight trend toward worsening hearing compared with the earlier follow-up, especially in the pediatric group, but the decrease was not significant, and the original gain from the preoperative level was maintained (see Table 1) [22]. The type of ossicular reconstruction (PORP versus TORP) had no apparent impact on hearing results. Because there may have been a trend for those patients experiencing Table 1 Comparison of short- and long-term hearing results in 50 ears undergoing retrograde mastoidectomy with canal wall reconstruction 2-Year postoperative
8-Year postoperative
Air–bone gap/dB
Number
Preoperative %
Number
%
Number
%
0–10 (excellent) 11–20 (good) 21–30 (fair) O30 (poor)
5 10 19 16
10 20 38 32
24 23 3 0
48 46 6 0
23 21 6 0
46 42 12 0
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no complaints to disregard long-term follow-up (all but one of the 14 patients who had not been recently seen were doing well), it is possible that our longer term data are biased toward worse outcomes. However, whether patients did not return for follow-up because they were doing well or because they were doing poorly is impossible to know with any degree of certainty. Summary The single-stage technique for cholesteatoma removal and canal wall reconstruction described here appears to be a valid procedure that can be performed as a single-stage surgery in greater that 90% of patients, both pediatric and adult. We found no difference between adults and children in either recurrence rates or hearing results. Nearly all primary cholesteatomas can be dealt with using this technique, except when more than 50% of the canal wall is destroyed with disease. Although our longer-term results have been encouraging, the need for long-term follow-up and continued management of Eustachian tube dysfunction is essential, as recurrences can be quite delayed. However, because cholesteatoma can recur fairly rapidly between the canal wall and tympanic membrane reconstruction, rigorous reconstruction with cartilage chips is advocated in this area. When recurrences do occur, they can be managed with removal and reinsertion of the canal, avoiding a CWD procedure in greater than 90% of cases. It appears that mesotympanic cholesteatomas may have a higher recurrence rate compared with epitympanic disease. Likewise, tobacco use is associated with a higher long-term complication rate, including recurrent cholesteatoma, perforation, poor hearing, and need for middle ear intubation as a second procedure. References [1] Arriaga MA. Cholesteatoma in children. Otolaryngol Clin North Am 1994;27(3):573–91. [2] Smyth GD. Cholesteatoma surgery: the influence of the canal wall. Laryngoscope 1985; 95(1):92–6. [3] Hirsch BE, Kamerer DB, Doshi S. Single-stage management of cholesteatoma. Otolaryngol Head Neck Surg 1992;106(4):351–4. [4] Austin DF. Single-stage surgery for cholesteatoma: an actuarial analysis. Am J Otol 1989; 10(6):419–25. [5] Schuring AG, Lippy WH, Rizer FM, et al. Staging for cholesteatoma in the child, adolescent, and adult. Ann Otol Rhinol Laryngol 1990;99(4 Pt 1):256–60. [6] Sheehy JL, Robinson JV. Revision tympanoplasty: residual and recurrent cholesteatoma. Paper presented at the Second International Conference on Cholesteatoma and Mastoid Surgery, Tel Aviv, Israel; 1982. [7] Glasscock ME 3rd. Results in cholesteatoma surgery. Paper presented at the First International Conference on Cholesteatoma, Birmingham, Alabama; 1977. [8] Nyrop M, Bonding P. Achievement of stable ears in cholesteatoma surgery: long-term results of three surgical techniques. Paper presented at the Fourth International Conference on Cholesteatoma and Mastoid Surgery, Niigata, Japan; 1993.
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[9] Cody DT, McDonald TJ. Mastoidectomy for acquired cholesteatoma: follow-up to 20 years. Laryngoscope 1984;94(8):1027–30. [10] Smyth GD. Surgical treatment of cholesteatoma: the role of staging in closed operations. Ann Otol Rhinol Laryngol 1988;97(6 Pt 1):667–9. [11] Black B. Mastoidectomy elimination: obliterate, reconstruct, or ablate? Am J Otol 1998; 19(5):551–7. [12] Grote JJ. Reconstruction of the middle ear with hydroxylapatite implants: long-term results. Ann Otol Rhinol Laryngol Suppl 1990;144:12–6. [13] Magnan J, Chays A, Pencroffi E, et al. Canal wall prosthesisdnew devices. Rev Laryngol Otol Rhinol (Bord) 1995;116(1):19–21. [14] Wullstein SR. Osteoplastic epitympanotomy. Ann Otol Rhinol Laryngol 1974;83(5):663–9. [15] Wiet RJ, Harvey SA, Pyle MG. Canal wall reconstruction: a newer implantation technique. Laryngoscope 1993;103(6):594–9. [16] Zini C, Quaranta N, Piazza F. Posterior canal wall reconstruction with titanium micro-mesh and bone pate. Laryngoscope 2002;112(4):753–6. [17] McElveen JT Jr, Chung AT. Reversible canal wall down mastoidectomy for acquired cholesteatomas: preliminary results. Laryngoscope 2003;113(6):1027–33. [18] Tos M. Mastoid surgery and reconstructive procedures. Vol. 2. New York: Thieme Publishers; 1995. [19] Dornhoffer JL, Gardner E. Prognostic factors in ossiculoplasty: a statistical staging system. Otol Neurotol 2001;22(3):299–304. [20] Dornhoffer JL. Hearing results with the Dornhoffer ossicular replacement prostheses. Laryngoscope 1998;108(4 Pt 1):531–6. [21] Dornhoffer JL. Retrograde mastoidectomy with canal wall reconstruction: a single-stage technique for cholesteatoma removal. Ann Otol Rhinol Laryngol 2000;109(11):1033–9. [22] Dornhoffer JL. Retrograde mastoidectomy with canal wall reconstruction: a follow-up report. Otol Neurotol 2004;25(5):653–60. [23] Stern SJ, Fazekas-May M. Cholesteatoma in the pediatric population: prognostic indicators for surgical decision making. Laryngoscope 1992;102(12 Pt 1):1349–52. [24] Becvarovski Z, Kartush JM. Smoking and tympanoplasty: implications for prognosis and the Middle Ear Risk Index (MERI). Laryngoscope 2001;111(10):1806–11.
Retrograde Mastoidectomy John L. Dornhoffer, MDa,b,c,* a
Division of Neurotology, Department of Otolaryngology/Head and Neck Surgery, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 543 Little Rock, AR 72205, USA b ENT Clinic and Audiology Services, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 543 Little Rock, AR 72205, USA c Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 543 Little Rock, AR 72205, USA
After nearly 5 decades of debate, the management of the posterior canal wall in cholesteatoma surgery remains a controversial issue. The canal wall up (CWU) tympanomastoidectomy preserves the normal anatomy of the ear canal, thus avoiding the risk of bowl problems and the necessity for periodic cleaning and leading to reduced healing time and, possibly, better hearing results [1]. Likewise, one must consider that surgery for cholesteatoma, which frequently involves complex ossicular reconstruction, may require hearing rehabilitation, with the need for amplification postoperatively. Hearing aid fitting after CWU surgery is generally straightforward and associated with fewer complications than that after canal wall down (CWD) tympanomastoidectomy. However, a high recitative rate (cholesteatoma left behind) and recurrence rate (recurrent retractions leading to cholesteatoma formation) continue to be major drawbacks to CWU surgery. At issue is the exposure of the critical anatomic regions for cholesteatoma removal: the epitympanum and associated supratubal recess and the mesotympanum. These are the two areas associated with most recurrent disease [2]. Primary acquired cholesteatomas typically begin as retraction pockets in the pars flaccida (epitympanic cholesteatoma) or posterior pars tensa (mesotympanic cholesteatoma). In the former situation, the sac typically forms in Prussak’s space, lateral to the malleus, and exits posteriorly or inferiorly, with some evidence of erosion of the scutum. The sac typically egresses lateral to the body of the incus into the antrum. With larger epitympanic cholesteatomas, one should anticipate extensive involvement of the epitympanic space and supratubal recess. The sinus tympani and facial recess can also be problematic, but are involved secondarily through inferior extension of the * Corresponding author. E-mail address: [email protected] 0030-6665/06/$ - see front matter Ó 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.otc.2006.08.002
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cholesteatoma into the mesotympanum. Mesotympanic cholesteatomas, on the other hand, arise from posterior retraction of the pars tensa and extend toward the antrum medial to the incus. In these cases, involvement of the sinus tympani and facial recess is very frequent, with extension to the epitympanum between the facial nerve and incus. CWU surgery, especially in cases with poorly developed zygomatic root cells and a low tegmun, can provide very limited exposure of the epitympanum and posterior mesotympanum, leading to blind and piecemeal removal of the cholesteatoma, which contributes to the high recitative rate. Frequently, the surgeon believes that the anterior epitympanic space has been reached, while in actuality only the bony cog has been exposed and disease is still present in the supratubal recess. Because of these short comings, second-stage surgery is frequently recommended 9 to 12 months after the initial CWU tympanomastoidectomy [3–5]. A review of the literature shows a wide variation in the reported recurrence rates with this technique. Sheehy and Robinson [6] initially reported recurrence rates of 5%, whereas Glasscock [7] reported a 14% recurrence rate. Recurrence rates up to 20% to 40% have also been reported [3,4]. As pointed out so aptly by Smyth [2], long-term results with CWU cholesteatoma can be very humbling, with recurrence rates of between 15% and 50%, even after staging. Nyrop and Bonding’s 10-year follow-up of CWU cases in Copenhagen showed that 70% required a later CWD surgery [8]. The CWD technique creates an open cavity after removal of the bony posterior canal wall, providing excellent exposure for cholesteatoma removal. The epitympanum, cog, and supratubal recess are widely exposed, facilitating complete removal of the cholesteatoma sac and lowering the recurrence rate to 5% to 10% [9,10]. Taking the canal wall down to the level of the facial ridge deals adequately with facial recess disease and affords improved, but by no means complete, view of the sinus tympani. In cases without sinus tympani involvement, this technique can also frequently be performed as a single-stage surgery. The main disadvantages of this technique are related to the necessity for periodic cleaning of the mastoid cavity [9,10]. Subsequent bowl infections can occur, especially when the cavity becomes wet, causing significant lifestyle changes, particularly in the pediatric age group [9]. In addition, the hearing results are frequently worse due to the shallow middle ear cleft [9,10]. Although bone-anchored hearing aids and open-mold technology have offered some new possibilities for amplification in this group, traditional hearing aid fitting can be very problematic due to a wet cavity, or widened, distorted meatus. Evolution of retrograde tympanomastoidectomy with canal reconstruction There has been a trend toward the development of surgical techniques that involve temporary removal of the canal wall, offering the exposure of CWD surgery for cholesteatoma extirpation, followed by reconstitution of the canal
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wall defect using autologous (bone, cartilage) or alloplastic (hydroxyapatite cement, titanium) graft materials [11–17]. The retrograde tympanomastoidectomy is one such technique that involves temporary removal of the upper canal wall, in association with a retrograde-type mastoidectomy, followed by reconstruction of the canal defect using Cymba cartilage. The posterior tympanic membrane is reconstructed with the cartilage palisade technique in close approximation with the canal reconstruction to inhibit recurrent retractions. Our 15-year experience with this technique has shown that the exposure of the epitympanum and upper mesotympanum is similar to CWD surgery, allowing single-stage surgery in 90% of cases, with 10-year recurrence rates very similar to those reported for CWD surgery. The primary indication for second-look or staged surgery is involvement of the sinus tympani with uncertain removal, which continues to be a difficulty with all techniques. Primary reconstruction of the ossicular chain is done in all cases, regardless of the need for a planned second surgery, as it acts as a scaffolding for the primary reconstruction. Before a detailed description of this technique is provided, it is worthwhile to consider its evolution. Conceptually, this technique seems to resemble an extended atticotomy; however, it actually represents a union of two divergent approaches: the osteoplastic flap of Wu¨llstein [14] and the small-cavity technique of Smyth [2]. Wu¨llstein recognized the advantage of this concept when he described osteoplastic flap surgery in 1974 [14]. A traditional CWU surgery was performed, followed by removal of the canal wall for exposure of the epitympanum, with subsequent reinsertion of the bony segment after cholesteatoma extirpation. Others have modified this technique by rigidly fixing the canal remnant with microplates and frequently using a vascularized pedicled flap for coverage [17]. Good preliminary results have been reported with these modifications [17]. However, the problem of a technically challenging fit, coupled with late bony necrosis of the reinserted graft, limited the routine acceptance of this technique [13]. Likewise, we have found that after the bony segment was removed, it was often necessary to drill anteriorly to further expose the supratubal recess, resulting in the bony segment becoming too small to be reused. Smyth’s small cavity surgery, on the other hand, described a technique that involved a CWD surgery by starting from the canal side, gradually enlarging it until complete exposure of the cholesteatoma was accomplished. This ended up creating a much smaller cavity than traditional CWD techniques, which involve a complete mastoidectomy, skeletonizing the sigmoid sinus and tegmen, and removing the canal wall when deemed necessary. With Smyth’s technique, it was found that when the mastoid was sclerotic, as is often the case with adult cholesteatomas, the cholesteatoma extended only to the antrum, resulting in a very small cavity. Professor Jan Helms, who succeeded Wu¨llstein at the University of Wu¨rzburg, performed an approach similar to Smyth’s, starting with a posterior canaloplasty and widening the canal until the air cells were first visible
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through the bone. The drilling then turned superiorly, skeletonizing the tegmun to the anterior malleolar ligament and following the cholesteatoma posteriorly into the antrum. The cholesteatoma frequently extended just to the antrum, in which case the canal wall defect was reconstructed with cartilage from the conchal bowl. The defect was typically small enough that the cartilage was supported superiorly at the zygomatic buttress, inferiorly at the posterior canal wall, and laterally at the mastoid cortex. If the cholesteatoma was more extensive, ‘‘turning the corner’’ into the mastoid tip, the canal could be taken down as described by Smyth [2]. This author has modified the technique to suit the large number of pediatric patients with cholesteatoma seen in his practice. These young patients tend to have larger cholesteatomas in more developed mastoids, requiring CWD surgery using the technique of Helms. This technique was then slightly modified to allow the cholesteatoma to be followed posteriorly, but if the disease ‘‘turned the corner’’ invading the mastoid tip, it was possible to follow the disease while leaving the lower two thirds of the posterior canal wall intact. This resulted in the need to perform more extensive grooving at the zygomatic buttress as well as the posterior canal wall to facilitate a cartilage reconstruction that would be supported only superiorly and inferiorly. This results in an optimized technique for cholesteatoma removal that represents the best of what the CWU and CWD procedures have to offer. It is described in detail below.
Surgical technique Cholesteatoma removal The mastoid cortex is widely exposed through a traditional postauricular skin incision. A tympanomeatal flap is then developed, and the middle ear is entered inferiorly, away from the cholesteatoma, to determine the extent of disease in the middle ear. As this technique involves extensive drilling in close proximity and just lateral to the head of the malleus and the body of the incus, it is necessary to visualize the incudostapedial joint and the integrity of the lenticular process of the incus as an initial step. Except in cases of very limited retraction pockets, the incudostapedial joint is disarticulated to avoid trauma to the inner ear from the subsequent drilling. A canaloplasty is performed posteriorly until air cells can just be visualized through the intact cortical bone of the ear canal. This improves the view of the posterior mesotympanum in cases of mesotympanic cholesteatomas and facilitates subsequent drilling of the upper canal wall as the cholesteatoma is followed up and back into the epitympanum and antrum. A prominent tympanosquamous suture and spine are taken off at this point to increase exposure of the pars flaccida. The drilling for cholesteatoma removal begins on the canal side with a 3 mm to 4 mm cutting burr at the upper posterior quadrant of the posterior
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canal wall, leaving a thin layer of bone at the scutum to protect the neck of the cholesteatoma, which is removed later with a diamond bur. This drilling differs from a traditional atticotomy in that it extends all the way to the lateral external canal as a groove, with exposure of the tegmun tympani. Anatomic landmarks that can be used for extent of canal wall removal would be the area between the anterior malleolar spine and, inferiorly, the approximate exit of the chorda tympani from the bone (9 o’clock to 1 o’clock in a right ear.) There are two important points to keep in mind during this portion of the drilling. One is that if more than 30% of the canal wall is removed, reconstruction becomes difficult. The most common mistake is to initiate drilling at too low a point relative to the anterior malleolar spine, underestimating the extent of anterior superior involvement. Subsequent drilling to expose the supratubal recess then leaves a larger canal wall defect than initially expected. It is always better to initiate this drilling high at the anterior malleolar spine, as approximated by the short process of the malleus. The other important point is that the tegmen at the lateral external canal frequently is more inferior than the more medial tegmen at the level of the epitympanum, so care must be taken to avoid injury to the dura laterally. While preoperative CT is not routinely performed, it can help predict the height of the tegmen on the coronal view; thus, its use may be advisable for those uninitiated with this technique. As bone removal continues posteriorly, the antrum is opened and the extent of the cholesteatoma can be appreciated. The goal is to remove only the bone necessary to expose the back edge of the sac, and a complete mastoidectomy is not necessary. With a small cholesteatoma in a sclerotic mastoid, the surgeon may frequently find the cholesteatoma extends only to the antrum, so minimal drilling is needed. The sac is followed back as posteriorly as necessary until normal air cell or cholesterol granuloma is encountered behind the sac. This technique differs from that described by Tos [18], in which a small cavity is created should extensive cholesteatoma be encountered. Instead, we follow the sac toward the mastoid tip, referred to as ‘‘turning the corner,’’ leaving the lower two thirds of the canal wall intact to facilitate reconstruction. This modification allows the removal of extensive cholesteatoma in a well-aerated mastoid, as frequently found in children, thus avoiding a CWD situation (Fig. 1). The diamond burr is then used to remove the thin bone over the cholesteatoma sac, taking extreme care not to violate the sac. The posterior edge of the sac is then identified, and this is dissected upward out of the mastoid cavity, following a posterior-to-anterior direction. This allows visualization of any fistula of the bony labyrinth (horizontal semicircular canal). When the mastoid portion of the cholesteatoma has been dissected free, the incus is removed, followed by the head of the malleus, to complete the exposure. At this point, the sac remains intact, and its neck entering the retraction in the tympanic membrane can be visualized and resected from this area, leaving a small defect in the tympanic membrane (Fig. 2).
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Fig. 1. Cholesteatoma is followed back posteriorly with exposure of entire sac at its origin from the tympanic membrane.
The exposure for cholesteatoma removal is very similar to a CWD situation and allows a nice progression of disease removal, with direct visualization of the horizontal canal, facial nerve, and oval window/stapes area. If necessary, one can drill the cog to follow disease in the supratubal recess. If disease extends anteriorly into the tubal orifice, it is possible to gain increased exposure by cutting the tensor tympani tendon. If possible, the tendon is left intact to facilitate and secure the ossicular reconstruction. Reconstruction Although removal of the cholesteatoma is important to reduce residual disease, reconstruction is equally important to prevent recurrence of
Fig. 2. Sac is resected, including the incus and head of malleus.
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retraction pockets. Primary ossicular reconstruction is performed in all ears, even when second-look surgery is planned, because the prosthesis acts as a scaffolding to support the cartilage reconstruction of the tympanic membrane and maintain the middle ear space during the healing phase. To reconstruct the canal wall, a 1 mm to 2 mm diamond burr is used to form grooves in the bone at the tegmen superiorly and in the inferior canal wall. The superior groove at the zygomatic root is very important and must be drilled properly to insure a good fit. The groove should be 1 mm to 2 mm wide and 2 mm deep and should be oriented parallel to the inferior canal to avoid torsion of the graft. Medially, the groove and subsequent reconstruction should extend down to and just posterior to the anterior malleolar spine and ligament so that is will approximate the cut edge of the malleus precisely. The inferior groove should be drilled carefully as the canal is frequently thin due to a combination of the canaloplasty and subsequent mastoidectomy. Often, a shelf, as opposed to a groove, is drilled here. Although we have experimented with other materials, autologous cartilage appears to be the ideal material for canal wall reconstruction. A piece of cartilage is harvested from the cymba of the conchal bowl to reconstruct the posterior canal wall. Because of its appropriate curvature, cartilage from the cymba is ideal for this purpose, and it generally has a uniform thickness of 1 mm. Generally, the cartilage will be 1 mm to 2 mm wider than the bony defect, allowing the canal wall reconstruction to snap into place under a little tension. The medial fit of the canal wall reconstruction is the most critical, and it is essential that a good fit between the cartilage and the residual bony canal wall be achieved and that the superior edge of the cartilage reconstruction be placed medially so that it closely approximates the handle of the malleus (Fig. 3). For ossicular reconstruction, we typically use hydroxyapatite prostheses and attempt to use the malleus in the reconstruction. It has been shown that incorporation of the malleus in ossicular reconstruction provides an acoustic gain, possibly due to its cantenary action in the tympanic membrane [19].
Fig. 3. Canal wall defect reconstructed with Cymba cartilage, with close proximity to the cut edge of the manubrium.
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Likewise, the presence of the malleus with an intact anterior malleolar ligament offers improved prosthesis stability by allowing precise length adjustments and ultimate fit, leading to optimal hearing results [20]. When the malleus handle and suspensory ligaments are present, we have found that a partial ossicular replacement prosthesis (PORP), which is 2 mm in length, and a total ossicular replacement prosthesis (TORP), cut to 4.0 mm to 4.5 mm, can be consistently used for precise reconstruction when the notch of the prosthesis is placed just inferior to the insertion of the tensor tympani (Fig. 4A and B). After precise ossicular reconstruction is performed, the posterior half of the tympanic membrane is reconstructed with pieces of cartilage using the modified palisade technique. With this technique, the tympanic membrane is put together like a jigsaw puzzle: the half moon-shaped piece is placed on top of the prosthesis first, abutting the malleus handle, followed by the scutum piece; any spaces left between these two plates and the canal wall are reconstructed with slivers of cartilage cut to fit precisely in these areas (Fig. 5A and B). The trifurcation of the malleus handle, canal reconstruction, and tympanic membrane reconstruction has proven to be critical for recurrence prevention, so small chips of cartilage are very important in this area. Likewise, if the drilling proceeds superior to the anterior malleolar ligament, care should be taken to reinforce this small area with cartilage. The reconstruction is then covered with perichondrium or fascia and the tympanic membrane remnant, if available. No space is left between the canal wall and reconstructed tympanic membrane to prevent cholesteatoma or retraction pocket recurrence. The anterior half of the tympanic membrane is typically not reconstructed with cartilage to allow postoperative surveillance and tube insertion, if necessary.
Fig. 4. (A) Schematic showing reconstruction of the ossicular chain after canal reconstruction. (B) Interoperative picture demonstrating reconstruction.
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Fig. 5. (A) Schematic showing reconstruction of the posterior tympanic membrane with the palisade technique. (B) Interoperative picture demonstrating precise fit between palisade reconstruction of the tympanic membrane and canal wall reconstruction.
The canal is then packed with antibiotic ointment, and a Pope Otowick (Xomed Co., Jacksonville, Florida) is placed in the ear canal. The packing is removed 10 days postsurgery, and the patient is instructed to perform the Valsalva maneuver three times a day, starting 2 weeks after the surgery. The Otovent (Abigo Medical, Sweden) has been used in children who are unable to perform this maneuver. The first postoperative audiogram is obtained 6 to 8 weeks postsurgery. If the patient is unable to perform the Valsalva maneuver or if the postoperative period is complicated by an effusion or retraction of the reconstructed tympanic membrane, a ventilation tube is placed 3 to 4 months after the surgery. Primary ventilation tube insertion is generally avoided. For the most part, the retrograde mastoidectomy allows removal of the cholesteatoma sac in one piece, with direct exposure, so second-look surgery is only performed in those cases where the cholesteatoma sac was violated and had to be removed piecemeal. The area of the sinus tympani is the most problematic region, as exposure here is difficult even with the retrograde mastoidectomy. Results with the retrograde mastoidectomy As of this writing, the retrograde technique has been used at our institution as the primary surgery for cholesteatoma removal for 13 consecutive years, resulting in an experience with over 400 ears. Short-term (2-year) and longer-term (8-year) results have been reported [21,22], indicating a dramatic reduction in recurrence rates and in need for a second surgery compared with our experience with CWU surgery [23]. We no longer perform CWD surgery as a primary surgery unless more than 50% of the canal wall is destroyed by disease or exterioration is needed because of large labyrinthine or cochlear fistulae, where the matrix cannot be safely removed. In our longer term study [22], we examined the results of 46 patients (representing 50 ears undergoing this procedure) who had an average 7-year follow-up. Second-look surgery was performed in 4% for questionable
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incomplete removal of disease in the sinus tympani or footplate area. One of these patients had residual disease at the footplate. We found recurrent cholesteatoma in eight ears (six adult and two pediatric), representing a recurrence rate of 16%. The site of the original cholesteatoma was evenly divided between the epitympanum and the mesotympanum. However, of the recurrent cholesteatomas, 63% had originally been mesotympanic and 37% had originally been epitympanic, suggesting a higher recurrence rate for mesotympanic cholesteatomas. This finding is not totally unexpected. The exposure of the epitympanum and supratubal recess is superior to the standard CWU approaches, and the removal is quite direct. The reason some ears develop epitympanic disease as opposed to mesotympanic cholesteatomas in the first place, from seemingly the same pathophysiologic mechanism (ie, Eustachian tube dysfunction), is unknown. It is possible that mesotympanic cholesteatomas result from more pervasive Eustachian tube dysfunction compared with epitympanic cholesteatomas, the latter of which may reflect anatomic or structural blockage of the antrum, which could be more easily corrected with surgical removal of the disease. Likewise, it appears that a ‘‘stable retraction’’ after cholesteatoma surgery may be an oxymoron. Both of the ears noted to have stable epitympanic retractions at the short-term assessment eventually developed cholesteatomas at longer follow-up. Thus, earlier or more aggressive intubation may need to be performed in those ears with early signs of retraction. The site of recurrence after reconstruction was typically in the epitympanic area (six of eight ears), just above the malleus handle, between the canal wall reconstruction and the tympanic membrane reconstruction. All six of these eight ears were revised, with removal of the previously inserted canal wall cartilage to expose the recurrent retraction, removal of the retraction, and reinsertion of the canal wall with reinforcement of the epitympanum. This recurrence pattern points out a relative weakness of the retrograde technique. Removal of the canal wall allows excellent exposure for complete removal of the cholesteatoma, leading to very low incidence of residual disease with a single-stage approach like CWD surgery. However, the reconstruction of the canal wall and posterior tympanic membrane is challenging, with a definite learning curve. Most of the recurrences in this series (four) were noted during the initial 2-year follow-up, and the area between the canal wall and tympanic membrane cartilage reconstruction was identified as a high-risk site. Because of this, much greater care is now taken to reinforce this area with chips of cartilage (Fig. 6). The effect of this modification is felt to be positive, but longer follow-up will be important in this cohort of patients. The negative impact of smoking on long-term results was apparent in our follow-up study [22] and has changed the way we counsel and treat patients who are smokers. If one includes as complications the presence of recurrent disease, need to intubate the ear postoperatively, occurrence of a perforation,
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Fig. 6. Postoperative picture after the retrograde technique. Area in ellipse demonstrates ‘‘high-risk’’ area reinforced with additional pieces of cartilage.
and need for a second-look surgery due to poor hearing results, the longterm complication rate of smokers was 79% (15/19 ears), compared with 16% (5/31 ears) for nonsmokers, making overall complications in smokers five times that seen in nonsmokers. Postoperative intubation for persistent effusion was necessary in nine individuals in this study, of which seven were smokers. Tobacco use has been reported to have a negative impact on graft take and hearing results during tympanoplasty [24], but its effect on long-term cholesteatoma recurrence has not been reported until recently. All but two of the recurrent cholesteatomas in our series were in individuals who routinely smoked cigarettes, making cholesteatoma recurrence almost five times higher for individuals who used tobacco. Long-term hearing results with the retrograde mastoidectomy technique have been encouraging, and compare favorably with those reported in staged ossiculoplasty [7]. In our longer term study, there was a slight trend toward worsening hearing compared with the earlier follow-up, especially in the pediatric group, but the decrease was not significant, and the original gain from the preoperative level was maintained (see Table 1) [22]. The type of ossicular reconstruction (PORP versus TORP) had no apparent impact on hearing results. Because there may have been a trend for those patients experiencing Table 1 Comparison of short- and long-term hearing results in 50 ears undergoing retrograde mastoidectomy with canal wall reconstruction 2-Year postoperative
8-Year postoperative
Air–bone gap/dB
Number
Preoperative %
Number
%
Number
%
0–10 (excellent) 11–20 (good) 21–30 (fair) O30 (poor)
5 10 19 16
10 20 38 32
24 23 3 0
48 46 6 0
23 21 6 0
46 42 12 0
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no complaints to disregard long-term follow-up (all but one of the 14 patients who had not been recently seen were doing well), it is possible that our longer term data are biased toward worse outcomes. However, whether patients did not return for follow-up because they were doing well or because they were doing poorly is impossible to know with any degree of certainty. Summary The single-stage technique for cholesteatoma removal and canal wall reconstruction described here appears to be a valid procedure that can be performed as a single-stage surgery in greater that 90% of patients, both pediatric and adult. We found no difference between adults and children in either recurrence rates or hearing results. Nearly all primary cholesteatomas can be dealt with using this technique, except when more than 50% of the canal wall is destroyed with disease. Although our longer-term results have been encouraging, the need for long-term follow-up and continued management of Eustachian tube dysfunction is essential, as recurrences can be quite delayed. However, because cholesteatoma can recur fairly rapidly between the canal wall and tympanic membrane reconstruction, rigorous reconstruction with cartilage chips is advocated in this area. When recurrences do occur, they can be managed with removal and reinsertion of the canal, avoiding a CWD procedure in greater than 90% of cases. It appears that mesotympanic cholesteatomas may have a higher recurrence rate compared with epitympanic disease. Likewise, tobacco use is associated with a higher long-term complication rate, including recurrent cholesteatoma, perforation, poor hearing, and need for middle ear intubation as a second procedure. References [1] Arriaga MA. Cholesteatoma in children. Otolaryngol Clin North Am 1994;27(3):573–91. [2] Smyth GD. Cholesteatoma surgery: the influence of the canal wall. Laryngoscope 1985; 95(1):92–6. [3] Hirsch BE, Kamerer DB, Doshi S. Single-stage management of cholesteatoma. Otolaryngol Head Neck Surg 1992;106(4):351–4. [4] Austin DF. Single-stage surgery for cholesteatoma: an actuarial analysis. Am J Otol 1989; 10(6):419–25. [5] Schuring AG, Lippy WH, Rizer FM, et al. Staging for cholesteatoma in the child, adolescent, and adult. Ann Otol Rhinol Laryngol 1990;99(4 Pt 1):256–60. [6] Sheehy JL, Robinson JV. Revision tympanoplasty: residual and recurrent cholesteatoma. Paper presented at the Second International Conference on Cholesteatoma and Mastoid Surgery, Tel Aviv, Israel; 1982. [7] Glasscock ME 3rd. Results in cholesteatoma surgery. Paper presented at the First International Conference on Cholesteatoma, Birmingham, Alabama; 1977. [8] Nyrop M, Bonding P. Achievement of stable ears in cholesteatoma surgery: long-term results of three surgical techniques. Paper presented at the Fourth International Conference on Cholesteatoma and Mastoid Surgery, Niigata, Japan; 1993.
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[9] Cody DT, McDonald TJ. Mastoidectomy for acquired cholesteatoma: follow-up to 20 years. Laryngoscope 1984;94(8):1027–30. [10] Smyth GD. Surgical treatment of cholesteatoma: the role of staging in closed operations. Ann Otol Rhinol Laryngol 1988;97(6 Pt 1):667–9. [11] Black B. Mastoidectomy elimination: obliterate, reconstruct, or ablate? Am J Otol 1998; 19(5):551–7. [12] Grote JJ. Reconstruction of the middle ear with hydroxylapatite implants: long-term results. Ann Otol Rhinol Laryngol Suppl 1990;144:12–6. [13] Magnan J, Chays A, Pencroffi E, et al. Canal wall prosthesisdnew devices. Rev Laryngol Otol Rhinol (Bord) 1995;116(1):19–21. [14] Wullstein SR. Osteoplastic epitympanotomy. Ann Otol Rhinol Laryngol 1974;83(5):663–9. [15] Wiet RJ, Harvey SA, Pyle MG. Canal wall reconstruction: a newer implantation technique. Laryngoscope 1993;103(6):594–9. [16] Zini C, Quaranta N, Piazza F. Posterior canal wall reconstruction with titanium micro-mesh and bone pate. Laryngoscope 2002;112(4):753–6. [17] McElveen JT Jr, Chung AT. Reversible canal wall down mastoidectomy for acquired cholesteatomas: preliminary results. Laryngoscope 2003;113(6):1027–33. [18] Tos M. Mastoid surgery and reconstructive procedures. Vol. 2. New York: Thieme Publishers; 1995. [19] Dornhoffer JL, Gardner E. Prognostic factors in ossiculoplasty: a statistical staging system. Otol Neurotol 2001;22(3):299–304. [20] Dornhoffer JL. Hearing results with the Dornhoffer ossicular replacement prostheses. Laryngoscope 1998;108(4 Pt 1):531–6. [21] Dornhoffer JL. Retrograde mastoidectomy with canal wall reconstruction: a single-stage technique for cholesteatoma removal. Ann Otol Rhinol Laryngol 2000;109(11):1033–9. [22] Dornhoffer JL. Retrograde mastoidectomy with canal wall reconstruction: a follow-up report. Otol Neurotol 2004;25(5):653–60. [23] Stern SJ, Fazekas-May M. Cholesteatoma in the pediatric population: prognostic indicators for surgical decision making. Laryngoscope 1992;102(12 Pt 1):1349–52. [24] Becvarovski Z, Kartush JM. Smoking and tympanoplasty: implications for prognosis and the Middle Ear Risk Index (MERI). Laryngoscope 2001;111(10):1806–11.