Revision stapedectomy: intraoperative findings, results, and review of the literature

The Impact of Surgical Expertise on the Cost-Effectiveness of Stapes Surgery

INTRODUCTION

Otosclerosis is the primary cause of conductive hearing loss with normal otoscopy. As the condition worsens, certain patients may develop a sensorineural component. Patients with successful surgeries may still need hearing aids, which creates a dilemma for health professionals as there are insufficient data to make informed decisions. This study investigated the influence of the surgeon's proficiency level, individual patient factors (e.g., age at the time of intervention and survival rates), and surgery costs on the cost-effectiveness of stapes surgery.

METHODS

We performed a cost-effectiveness analysis using an adapted Markov model incorporating annual all-cause mortalities. In addition, we introduced sensitivity analyses to address the effects of surgical expertise on adults with bilateral conductive hearing loss due to otosclerosis. A model was developed based on a decision tree with treatment options and complication scenarios for otosclerosis patients undergoing stapes surgery or receiving hearing aids. Annual all-cause mortality was considered. A sensitivity analysis was performed assigned to different training levels ("experts" and "less experienced") to simulate the effects of surgical experience on the cost-effectiveness of surgical outcomes. Successful surgery was defined as closing of the air-bone gap to 10 dB or less. Based on published data, "experts" were simulated with a 93.7% success rate, and "less experienced" were manufactured with a 68.9% success rate.

RESULTS

Stapes surgery provides improved quality of life (QoL) compared to hearing aids with lower cumulative costs up to 87 years of age in the case of "expert" surgeons and up to 78 years of age, when performed by "less experienced" surgeons.

CONCLUSIONS

Primary stapes surgery is highly cost-effective and delivers improved QoL compared to hearing aids with lower cumulative costs. Additionally, undergoing stapes surgical training remains highly cost-effective.

Recurrence of conductive hearing loss after stapes surgery: a narrative review

Among the functional failures of stapes surgery is recurrent conductive hearing loss, which can occur after a variable period of hearing improvement, from days/months up to many years after surgery. The most common cause of recurrent conductive hearing loss is prosthesis displacement, while fibrous adhesions or stapedotomy hole/oval window re-obliteration due to otosclerosis, occur less frequently. High resolution computed tomography plays an important role in the identification of the cause of hearing loss recurrence. Parallel to this, intra-operative exploration of the middle ear is crucial to confirm the cause of failure and address its treatment, possibly restoring hearing. While generally worse than after primary surgery, hearing outcomes after revision stapes surgery have improved thanks to advancements in pre-operative assessment, intra-operative view and technical refinements.

Long Process Incus necrosis in Revision Stapedotomy: Retrospective Clinical Study

OBJECTIVES

We describe our experience with long process incus (LPI) necrosis in revision stapedotomy and discuss the different management methods proposed in the literature to identify surgical techniques that can lead to satisfactory results over time.

METHODS

Twenty-two stapedotomy revisions, in 21 patients with the necrosis of the long process of the incus, are performed from 1997 to 2017. In cases of erosion or minimal necrosis of LPI, a new prosthesis of the same type or an angled prosthesis was applied higher on the residual incus stump. In cases of partial necrosis of LPI, a Donaldson type ventilation tube reshaped and placed on the residual incus stump to stabilize prosthesis, or glass ionomer bone cement was used. In cases of subtotal necrosis of LPI, a cup piston prosthesis in polycel was applied on incus residual stump. Pre- and postoperative (≥1 year) pure tone audiometry was performed for all cases. Air conduction threshold, bone conduction (BC) threshold, and air-bone gap (ABG) were documented according to the American Academy of Otolaryngology Head and Neck Surgery Committee of Hearing and Equilibrium guidelines.

RESULTS

At 1-year follow-up, postoperative ABG was reduced to ≤10 dB in 13 (59%) cases and ≤20 dB in 19 (86.4%) cases. The mean postoperative ABG significantly decreased in each group. There was no significant change in postoperative BC thresholds, and there were no cases with postoperative SNHL.

CONCLUSION

Excellent functional results can also be achieved in cases of long incus process necrosis. The choice of technique should be considered according to the degree of necrosis. Piston replacement with the same type or angled type prosthesis, in cases of erosion or minimal LPI necrosis, and modified Donaldson type ventilation tube, in cases of partial LPI necrosis, provided excellent hearing results.

Incus Necrosis and Blood Supply: A Micro-CT and Synchrotron Imaging Study

BACKGROUND

Incus necrosis is a common complication following stapes surgery and is associated with impaired microcirculation. The objective of this study was to investigate the vascular anatomy of the human incus by using light microscopy, micro-computed tomography (micro-CT), and synchrotron phase-contrast imaging (SR-PCI) for a novel three-dimensional (3D) analysis of the middle ear, mucosal folds, major vascular pathways, and intraosseous vascular bone channels.

METHODS

One-hundred-and-fifty temporal bones from the Uppsala collection were analyzed under light microscopy. Twenty temporal bones underwent high-resolution micro-CT scanning, and an additional seven specimens underwent SR-PCI at the Canadian Lightsource in Saskatoon, Canada. One of these specimens was from an individual who had undergone stapes surgery. Data were processed with volume-rendering software to create 3D reconstructions using scalar opacity mapping for bone transparency, cropping, and soft tissue analyses.

RESULTS

Micro-CT and SR-PCI with 3D rendering revealed the extensive vascular plexus within the un-decalcified incus bone communicating with the exterior surface. The relationship between the vessels, lenticular process, and incudostapedial joint were clearly observed. SR-PCI allowed for histologic-level detail while preserving the specimen and its 3D relationships.

CONCLUSION

SR-PCI with 3D reconstructions confirmed the main vascular supply to the lenticular process along the intraosseous lenticular vessels. This is the first synchrotron analysis of a patient having undergone stapes surgery, and it suggests that incus necrosis associated with stapes surgery may be caused by a disruption of the lenticular blood flow induced by the prosthesis loop, and not by strangulation of mucosal vessels as has been previously described.

Revision Stapes Surgery in a Tertiary Referral Center: Surgical and Audiometric Outcomes

Objectives:

To evaluate pure-tone audiometric results in otosclerosis patients undergoing revision stapes surgery following previous middle ear interventions.

Methods:

A retrospective cohort study was performed in a tertiary referral center. Consecutive otosclerosis patients who underwent revision stapes surgeries, following previous middle ear interventions, for persistent conductive hearing loss, recurrent conductive hearing loss, or vertigo and had available postoperative pure-tone audiometry were included. Mean pre- and postoperative air conduction, bone conduction, and air-bone gap averaged over 0.5, 1, 2, and 3 kHz were obtained. Audiometric outcomes were obtained at 7 weeks postoperatively.

Results:

In total, 63 consecutive otosclerosis patients who underwent 66 revision stapes surgeries were included. Air-bone gap improved significantly with a mean gain of 19 dB (95% CI, 15-22). Air conduction improved significantly with a mean gain of 18 dB (95% CI, 14-23). Bone conduction did not change significantly, with a mean deterioration of 0 dB (95% CI, –2 to 1). Air-bone gap closure to 10 dB or less was achieved in 38% of cases and to 20 dB or less in 80% of cases. Indication for surgery, previous type of procedure, primary cause of failure, and current surgical technique were not significantly associated with air-bone gap closure to 10 dB or less. Indication for surgery and primary cause of failure were associated with one another.

Conclusions:

Compared to the available literature, a slightly larger gain in air conduction and air-bone gap was achieved in our study. Air-bone gap closure to 10 dB or less was achieved less often in our study.

Assessing ototoxicity and patients' satisfaction of topical local anaesthesia in myringotomy and ventilation tube insertion

OBJECTIVES

Animal studies have suggested that exposure of the middle ear to topical local anaesthesia may be ototoxic. This study aimed to report sensorineural hearing outcomes and patients' satisfaction in those who underwent myringotomy and ventilation tube insertion using topical local anaesthesia.

METHODS

Twenty-nine patients (32 ears) were operated on. Pre- and post-operative audiology findings were compared. A Likert-type questionnaire on treatment satisfaction was completed at the end of the procedure.

RESULTS

Median patient age was 55 years (range, 27-88 years). Pre- and post-operative bone conduction pure tone averages were 26.76 dB and 25.26 dB respectively (mean reduction of -1.22 dB, 95 per cent confidence interval of -5.91 to 8.13 dB; p = 0.7538). One ear (3 per cent) had a reduction in pure tone average of 10 dB.

CONCLUSION

The results suggest that sensorineural hearing loss is not a complication of ear exposure to topical local anaesthesia during myringotomy and ventilation tube insertion. The procedure was well perceived.

Conductive hearing loss with a "dry middle ear cleft"-A comprehensive pictorial review with CT

Conductive hearing loss (CHL) commonly results from middle ear fluid and inflammation (otitis media). Less commonly in patients with CHL, the middle ear cleft is well aerated or 'dry' with absence of soft tissue or fluid clinically and on imaging. There are numerous causes for this but they can be clinically challenging to diagnose. This pictorial review aims to illustrate and discuss the CT features of both common and less common causes of CHL in patients with a "dry middle ear cavity".

Predictable prosthesis length on a high-resolution CT scan before a stapedotomy

OBJECTIVE

(1) To assess the correlation between preoperative high-resolution CT (HRCT) imaging measurement from the long process of the incus to the footplate and the length of intraoperative selected prosthesis. (2) To determine if HRCT has a predictive value of prolapsed facial nerve during stapedotomy.

MATERIALS AND METHODS

We evaluated in our tertiary care center, in a retrospective case series, 94 patients undergoing primary stapedotomy. Preoperative temporal bone HRCT scans were reformatted in the plane of the stapes to measure on the same section the distance between the long process of the incus and the footplate. Measurement was performed by otolaryngology resident and neurotologist. We analyze the interobserver correlation and the mean length measured on the HRCT to the selected prosthesis size intraoperatively.

RESULTS

Mean HRCT measurement of the incus long process/footplate distance assessed by the otolaryngology resident and neurotologist was 4.34 and 4.38 mm, respectively. Interobserver correlation was statistically significant [intraclass correlation coefficient (ICC) of 0.679 (p < 0.001)]. Mean selected prosthesis length intraoperatively was 4.36 mm. Correlation between the mean selected length prosthesis and the mean HRCT measurement was also statistically significant [ICC of 0.791 (p < 0.001)]. Postoperatively, a statistical improvement was shown in air conduction (p < 0.001), bone conduction (p < 0.001) and air-bone gap reduction (p < 0.001). 2 cases of facial nerve covering one-half of the oval window were identified by HRCT and confirmed intraoperatively.

CONCLUSION

HRCT is a valuable tool to predict preoperatively the length of the stapedotomy prosthesis. Moreover, it might be helpful to identify a potential prolapsed facial nerve, to confirm the diagnosis of otosclerosis and to rule out other abnormalities. Ultimately, it may optimize the stapedotomy procedure planning.

Revision surgery for otosclerosis: An overview

Stapes surgery for otosclerosis has been proved to be a very satisfying procedure. However, the condition is difficult for the patients with no or little hearing gain after surgery and for those who had sudden or gradual hearing loss after a successful air-bone gap closure in the follow-up period. The issue of re-exploring the middle ear is challenging. A general review of this subject from several points of view remains lacking. In this study, articles related with the revision surgery for otosclerosis have been reviewed after a PubMed research and common and/or contradictory points were documented. The aim of this study is to give an insight to diagnostic and therapeutic approaches for the clinicians in patients who need a revision surgery. In conclusion, prosthesis problems, loose prosthesis in stapedotomy and migrated prosthesis in stapedectomy are the most common causes for revision surgery. Most important indicators which effect better hearing outcome following revision surgery are those ears with the presence of incus, with no obliteration of oval window, with small fenestra stapedotomy and the experience of surgeon. The risk of neurosensorial hearing loss in revision cases is not high but the hearing gain is limited as compared to primary cases. The rate of 10 dB air-bone gap closure is around 60%-70% at most and even less promising results have been reported. Patient’s demands and expectations have to be clarified in a realistic way.

Revision Stapes Surgery

Objectives. Surgery for otosclerosis has a highly satisfactory hearing outcome, for both the patient and the otologic surgeon. However, subsequent conductive hearing loss, dizziness/vertigo, or sound distortion could necessitate revision surgery. The aim of the present study is to evaluate the surgical findings and hearing outcomes of 84 revision stapes surgeries.

Study Design. Case series with chart review.

Setting. Tertiary referral center.

Subjects and Methods. At our institution, 84 revision cases were performed between 1998 and 2009. Conductive hearing loss was the revision indication in 69 cases, severe dizziness/vertigo in 8 patients, sound distortion in 5 cases, and progressive hearing loss with dizziness in 2 patients. Operative findings were noted in every case and evaluated separately.

Results. Surgical intervention revealed problems related to prosthesis in 51 cases, fibrotic bands in 26 cases, adhesions in 13 cases, incus necrosis in 15 cases, perilymphatic fistula in 3 cases, intact footplate in 5 cases, incus-malleus fixation in 2 cases, and reobliteration in 2 cases. Mean follow-up period was 19 months (range, 12-53 months). Successful hearing results (air-bone gap <10 dB) were reached in 58% of the cases, and satisfactory hearing results (air-bone gap <20 dB) were reached in 71% of the cases.

Conclusions. The ideal patient for revision stapes surgery is one who benefits from the initial surgery but complained of conductive hearing loss. In the present study, improvement in pure-tone average was 13.2 dB, and the mean air-bone gap was 9.6 dB.

Persistent and recurrent conductive deafness following stapedotomy

Background:

Stapedotomy produces the best hearing results of any otological operation. However, in a small number of cases the air–bone gap is not successfully closed, or conductive hearing loss recurs.

Objective:

To investigate the proportion of cases in the senior author's series which required revision surgery and to determine the medium to long term success rate of surgery, taking into account the results of revision surgery.

Methods:

Review of a series of 233 primary stapedotomy operations and 100 revision procedures carried out by one surgeon over a 20-year period.

Results:

Closure of the air–bone gap to within 10 dB was achieved in 80 per cent of cases following the primary procedure. Fifteen per cent of patients developed a recurrence of conductive hearing loss. When the results of revision surgery were taken into account, the proportion of ears with a mean air–bone gap of less than 10 dB was 86 per cent. However, of the patients undergoing revision surgery, air–bone gap closure to within 10 dB was only achieved in 52 per cent of cases.

Conclusion:

The best chance of obtaining a successful outcome in stapedotomy is to achieve this for the first procedure. However, revision surgery does increase the medium to long term success rate.

A review of 89 revision stapes surgeries for otosclerosis

OBJECTIVES

The aim of this study was to identify the causes and the audiometric results of revision surgery following stapedotomies and stapedectomies.

PATIENTS AND METHODS

We retrospectively reviewed a series of 89 revisions after surgery for otosclerosis between 1993 and 2008. Intraoperative findings, causes of failure, and pre- and postoperative audiometric results were noted retrospectively.

RESULTS

The leading causes of failure found intraoperatively included dislocated prosthesis and necrosis of the long process of the incus. The average postoperative air-bone gap was 13 dB. Closure of the air-bone gap to within 10 dB was achieved in 52% of patients.

CONCLUSION

Stapes revisions had less satisfactory results compared with primary procedures in this series. However, certain precautions during initial surgery should decrease the number of stapes surgery revisions.

Revision stapes surgery: the “lateralized piston syndrome”. Otol Neurotol. 2009;30:1138-1144. [PMID: 19953702 DOI: 10.1097/mao.0b013e3181c0e80f]

OBJECTIVE

The need for revision stapes surgery has many causes, and among these, we describe a particular displacement of the piston: the "lateralized piston syndrome". The goal of this study is to define criteria and surgical management of this syndrome.

STUDY DESIGN

Retrospective study over 13 years.

SETTING

Tertiary reference center.

PATIENTS

A review of 1,289 consecutive stapes operations revealed 119 revisions (9%) from which 22 cases (18.5%) could be classified under the lateralized piston syndrome.

INTERVENTION

Revision stapedotomy.

MAIN OUTCOME MEASURES

Medical files, preoperative and postoperative audiograms, computed tomographic scans, and operative reports.

RESULTS

The 22 cases presented as a delayed conductive hearing loss in 95.5% of cases. Preoperative computed tomographic scans showed a lateralized piston out of the stapedotomy in 81% of cases and touching the tympanic membrane in 54.5% of cases. Revisions revealed a lateral displacement of the piston out of the entire oval window in 86% of cases, with closure of the stapedotomy in all cases and incus necrosis in 77% of cases. Conventional pistons were fitted in 12 cases. In case of a significantly eroded incus, total prostheses (TORPs) in 6 cases and offset pistons in 4 cases were placed. Air-bone gap (ABG) was closed to within 20 dB in 82% of cases. Air-conduction puretone audiometry improvement was 17.2 dB (standard deviation [SD], 19.2), with a mean postoperative ABG of 16.2 dB (SD, 12.7). Only 1 ear, operated with TORP, had a sensorineural deterioration of 20 dB. With offset pistons, ABG was closed to within 20 dB in 100% of cases with a mean postoperative ABG of 8.8 dB (SD, 7.2).

CONCLUSION

The lateralized piston syndrome was found in 18.5% of stapes surgery revisions. Surgical management was effective in correcting the conductive hearing loss. In the event of significant eroded incus, we observed better results with offset pistons than with TORPs.

Prospective electrophysiologic findings of round window stimulation in a model of experimentally induced stapes fixation. Otol Neurotol. 2009;30:1215-1224. [PMID: 19779388 DOI: 10.1097/mao.0b013e3181bc3c06]

HYPOTHESIS

Mechanical stimulation of the round window (RW) with an active middle ear implant (AMEI) with and without experimentally induced stapes fixation (SF) results in equivalent electrophysiologic measures of cochlear microphonic (CM), compound action potential (CAP), and auditory brainstem response (ABR).

BACKGROUND

Where normal oval window functionality is mitigated, the RW provides a pathway to mechanically stimulate the inner ear.

METHODS

Measurements of the CM, CAP, and ABR were made in 5 ears of 4 chinchillas with acoustic stimulation and with application of the AMEI to the RW with and without experimentally induced SF using pure-tone stimuli (0.25-20 kHz) presented at differing intensities (-20 to 80 dB SPL vs. 0.01 mV to 3.16 V).

RESULTS

Morphologies of the CM, CAP, and ABR were similar between acoustic and RW stimulation with and without SF. Stapes fixation increased CM thresholds relative to RW stimulation without fixation by a frequency-dependent 4- to 13-dB mV (mean, 7.9 +/- 3.2 dB mV). Although the thresholds changed with SF, CM sensitivities and amplitude dynamic range were identical to normal. The CAP in all conditions demonstrated equivalent decreasing amplitudes and increasing latency with decreasing intensity (decibel sound pressure level versus decibel millivolt). Stapes fixation increased the CAP thresholds at all frequencies, ranging from 9 to 24 dB mV (mean, 17.7 +/- 4.9 dB mV). Auditory brainstem response waveforms were preserved across experimental conditions.

CONCLUSION

Mechanical stimulation of the RW in an animal model of SF generates functionally similar inputs to the cochlea as normal acoustic and RW mechanical inputs but with increased thresholds. With further study, AMEIs may provide a surgical option for correction of otosclerosis and ossicular chain disruption.

Failures in stapedotomy for otosclerosis

OBJECTIVE

To review the results of 78 revision stapedotomies, determining the causes of failure and the predictors of surgical success.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary referral center.

SUBJECTS AND METHODS

Seventy-eight operations were performed in a tertiary referral center on 72 patients between 1995 and 2005. Indication for surgery was recurrent or persistent conductive hearing loss.

RESULTS

The most common causes of failure were prosthesis displacement, incus necrosis, and oval window fibrosis. Postoperative air-bone gap was closed to within 10 dB in 54 percent of cases, and mean postoperative air-bone gap was 13.6 dB. Overclosure occurred in five percent of cases, sensorineural hearing loss in six percent of cases, and we had one postoperative dead ear. Success rates were higher in cases presenting prosthesis or ossicular malfunction than in cases with oval window problems. Hearing results did not differ if the prosthesis was crimped to either the malleus or the remnant of the long incudal process. Outcomes were similar for local or general anesthesia, and the nitinol piston did not significantly improve the hearing results.

CONCLUSION

Revision stapedotomy is less successful than primary procedure. Lessening the surgical trauma provides the most favorable results.

The influence of postoperative tissue formation on sound transmission after stapes surgery

In the surgical treatment of otosclerosis, the coupling between the stapes prosthesis and the long process of the incus is critical. After surgery, connective tissue and mucosa may grow over the coupling area and thereby influence the sound transmission properties of the incus-prosthesis interface. It was the hypothesis of this study that tissue ongrowth in the incus-prosthesis interface has little influence on sound transmission following stapes surgery. The goals of the study were to: (1) investigate the extent of postoperative tissue ongrowth over the stapes prosthesis; (2) objectively evaluate intra- and postoperative sound transmission properties of revision stapes surgery and compare the findings to those from primary surgery; (3) quantify the influence of ongrown tissue on sound transmission after stapes surgery. A group of 10 patients undergoing revision stapes surgery was investigated with audiological evaluations and intraoperative laser Doppler interferometry, and with scanning electron microscopy of the explanted incus with its adherent prosthesis in 6 patients. Results were compared to a group of patients undergoing primary otosclerosis surgery and temporal bone experiments. Results indicated that tissue grows over the prosthesis, as identified in all specimens. Sound transmission properties were evaluated intraoperatively (i.e., incus mobility and prosthesis-fixation quality), and found to correlate well with the functional hearing results. Ongrowing mucosa in the incus-prosthesis interface had only a minimal effect on sound transmission properties and cannot compensate adequately for insufficient prosthesis fixation. Therefore, it is essential that the stapes prosthesis is properly fixed during primary otosclerosis surgery.

The Effect of CO(2) and KTP laser on the cat saccule and utricle

OBJECTIVES/HYPOTHESIS

To assess the potential carbon dioxide (CO(2)) and potassium-titanyl-phosphate (KTP) laser-related trauma to the saccule and utricle in a cat model.

STUDY DESIGN

Basic science experiment utilizing cat model.

METHODS

Twelve adult male cats were divided into two groups-CO(2) and KTP-to assess the potential saccule and/or utricle trauma with direct discharge of laser energy into the vestibule after the stapes was removed. Both groups were subdivided to assess the effects with acute sacrifice and three-month survival. Bone conduction auditory brain-stem response thresholds were used to monitor auditory function. Clinical observation was used to monitor vestibular function. The temporal bones were harvested, processed, and stained with hematoxylin and eosin (H&E) in all animals with the uninvolved side serving as the control.

RESULTS

None of the animals demonstrated changes in bone conduction auditory brain-stem responses. None of the animals in the survival group demonstrated clinical vestibular dysfunction. Saccular and utricular wall rupture was observed in all animals sacrificed acutely. None of the saccular and utricular wall ruptures were of a size and location that could be attributed to laser trauma, and none of the saccular and utricular wall ruptures were associated with neuroepithelial trauma.

CONCLUSIONS

There is no evidence of a difference between the CO(2) and KTP laser in potential laser-related trauma. Using bone-conducting auditory brain-stem response threshold and clinical monitoring of vestibular function, there was no evidence of clinical auditory or vestibular dysfunction. The histologic evidence of saccular and utricular wall rupture is more consistent with stapes extraction trauma than laser-related trauma.

Preliminary results of applying the inverse stapedotomy

The authors have analyzed a group of 90 patients (105 operations) that have underwent stapes surgery over three years period. First group of 40 patients (45 operations) have been operated on by a classic stapedotomy from 2006 to 2007 and the second group of 50 patients (60 operations) by inverse stapedotomy in 2007. Manual perforator has been used in all of the patients. In a group of patients operated by inverse technique not a single case of floating basal plate has occurred during surgery. Rate of postoperative complaints regarding nausea and balance disorders was considerably lower when reversal of the steps has been used. Closure of air bone gap better than 20dB in about 80% patients in both series, with slight advantage of the inverse technique, but no statistically significant difference was proven. Inverse stapedotomy is efficient procedure as compared to classic stapedotomy with less intraoperative complications and postoperative complaints. Postoperative audiograms have shown similar improvement of hearing thresholds in both groups.

[Significance of computed tomography evaluation before revision stapes surgery]

BACKGROUND

Stapedectomy and, more recently, stapedotomy have been widely accepted as the primary surgical techniques to improve conductive hearing in patients suffering from otosclerosis. Unsuccessful outcomes are infrequent, but revision surgery may become necessary. We have analyzed the value of computed tomography (CT) scanning following unsuccessful stapes surgery.

PATIENTS AND METHODS

In a total of 37 CT scans, the depth of insertion, angle between prosthesis and footplate, location of prosthesis within the oval niche, visibility of the prosthesis, dehiscence of the superior semicircular canal, and extent of otospongiotic foci were evaluated and compared with the audiometric results.

RESULTS

There was no significant correlation between CT parameters and audiologic results, except for patients with cochlear otosclerosis or lateral dislocation of the piston. One previously unknown dehiscence of the superior semicircular canal was diagnosed. Otospongiotic foci were seen in 13 ears (35%).

CONCLUSION

Displacements of the stapes piston and rare causes for an insufficient result, such as a dehiscence of the superior semicircular canal, can be diagnosed accurately by CT. However, correlation between the audiologic results and the findings on CT scans was possible in only a few cases. Nevertheless, CT scans provide additional information for surgical planning in revision stapes surgery and may become increasingly important to reduce unanticipated intraoperative risks; they may even guide the surgeon not to perform unnecessary revision surgeries.

Revision Stapedectomy

Revision stapedectomy can be a technically demanding operation. The surgeon must be prepared for many pathologic conditions before revision stapes surgery. Appropriate preoperative patient counseling is a must. The best chance for hearing improvement is in those cases that have a delayed conductive hearing loss after primary stapedectomy. This article serves as a guideline for discussing the myriad possibilities that may be encountered during this type of revision stapedectomy. Indications for revision stapedectomy and general surgical guidelines for management of specific pathologic conditions are discussed. The material presented is based on literature review, the authors' personal experience, and a review of temporal bone studies relative to stapes surgery.

Results after revision stapedectomy with malleus grip prosthesis

Revision stapedectomy with a malleus grip prosthesis is a technically challenging otologic procedure. The prosthesis is usually longer and extends deeper into the vestibule than a conventional stapes prosthesis, creating the potential to affect the vestibular sense organs. The prosthesis also bypasses the ossicular joints, which are thought to play a role in protecting the inner ear from large changes in static pressure within the middle ear. The prosthesis is in close proximity to the tympanic membrane, thus increasing the risk for its extrusion. We reviewed our experience with revision stapedectomy with the Schuknecht Teflon-wire malleus grip prosthesis in 36 ears with a mean follow-up of 23 months. The air-bone gap was closed to within 10 dB in 16 ears (44%) and to within 20 dB in 26 ears (72%). The incidence of postoperative sensorineural hearing loss was 8% (3 ears). There were no dead ears. Extrusion of the prosthesis occurred in 1 case (3%). Nearly 50% of patients reported various degrees of vertigo or disequilibrium during the first 3 weeks after surgery. These vestibular symptoms resolved by 6 weeks in all but 1 case. We did not find evidence of damage to the inner ear due to the length of the prosthesis or due to the potential for direct transmission of changes in static pressures within the middle ear to the labyrinth. Our results are similar to those published in the literature for malleus attachment stapedectomy and conventional revision incus stapedectomy.

[Auditory results used to compare a Teflon prosthesis vs a Schucknecht type wire/Teflon prosthesis]

PURPOSE

To compare a Teflon prosthesis to a piston-type wire/Teflon prosthesis assessing auditory results post-Stapedectomy.

MATERIAL AND METHODS

We conducted a randomized controlled blinded clinical study from June 2003 to August 2004 at the Otorhinolaryngology, and Head and Neck Surgical Wards at the highly specialized medical unit of "La Raza" General Hospital National Medical Cen ter in Mexico City. The study group was comprised by patients receiving a Teflon prosthesis (Fluoroplastic piston) while the control group received a Schuckneckt type piston wire/Teflon prosthesis. A pre- and post-auditory assessment was done obtaining the average at low, medium and high airway frequencies, the air/bone frequency differences and the total, at the Audiology and Otoneurology Service at the same hospital using a Madzen Minimate 602 brand audiometer. The results were analyzed using SPSS statistical software version 8.0.

RESULTS

138 patients were studied: 68 were included in the study group (Fluoroplastic prosthesis) and 70 in the control group (wire/Teflon prosthesis). A statistically significant difference was found between the groups (p < 0.04) according to the Mann-Whitney U test. The air/bone closure difference was statistically significant (p < 0.001) at low and high frequency ranges for the study group.

Success rate in revision stapes surgery for otosclerosis

OBJECTIVE

The aim of this study was to evaluate the hearing results of revision stapes surgery performed because of previously failed operations and to determine the causes of failure.

STUDY DESIGN

Retrospective review of revision stapes operations.

SETTING

Tertiary referral center.

PATIENTS

Sixty-three consecutive revision stapes operations were performed in 56 patients over a period of 12 years (1992-2004). The indication for revision surgery was recurrent or persistent air-bone gap greater than 20 dB after primary surgical treatment of otosclerosis of the oval window.

RESULTS

All patients were operated on to improve hearing. Sixty-three revision stapes operations resulted in closure of the air-bone gap to 10 dB or less in 52.4% of cases. The average postoperative air-bone gap was 13.1 dB, and the mean pure-tone average improvement was 12.9 dB. In six patients (9.5%), revision surgery produced no change in hearing, and in four (6.3%) the hearing decreased by 5 dB or more. In one patient, the operation resulted in a profound hearing loss. Prosthesis malfunction was the most common primary cause of failure (60.3%). The original prosthesis was replaced with a new one in 48 cases. In 30 of these (62.5%), closure of the air-bone gap to within 10 dB was achieved. In 15 cases, the prosthesis was not replaced, and in only four of these (26.7%), closure of the air-bone gap within 10 dB was obtained (p < 0.022).

CONCLUSION

Revision stapes surgery is less likely to be successful than the primary operation. Closure of the air-bone gap to within 10 dB was achieved in 52.4% of patients. The success rate was better in cases where the original prosthesis was replaced with a new one. The risk for decreased bone-conduction threshold does not seem to be higher than in primary surgery.

Imagerie des échecs et complications post-opératoires de la chirurgie de l’otospongiose

Otosclerosis (OS) is a dysplasia of the otic capsule located in most cases on the anterior margin of the oval window or fissula ante fenestrum. Progressive conductive hearing loss is the major clinical symptom, due to stapedovestibular ankylosis. Stapes surgery is the only effective treatment of OS, with excellent functional results in more than 90% of cases. However, failures and complications of the surgery may be observed. In theses cases, the etiologic work-up includes imaging evaluation (CT and MRI). Imaging findings are extremely useful in the therapeutic decision. Surgical failure represents 80% of the causes for surgical revision. The main causes of failure are: displacement of the prosthesis, fibrosis of the oval window, erosion of the long process of the incus, incudo-mallear dislocation, obliterative otosclerosis. CT is essential for diagnosis. MR imaging is rarely indicated in the work-up of surgical failures. Labyrinthine complications account for less than 20% of surgical revisions. Etiologies of labyrinthine complications are: intravestibular penetration of the prosthesis, perilymphatic fistula, intra-vestibular granuloma, labyrinthitis and intravestibular bleeding. CT and MRI are complementary for the work up of these complications.

Poststapedectomy Hearing Gain: Comparison of a Teflon (fluoroplastic ASTM F 754) Prosthesis with a Schuknecht-type Wire/Teflon Prosthesis

We conducted a retrospective study to compare poststapedectomy hearing gain in study-eligible patients who had received a Teflon (fluoroplastic ASTM F 754) prosthesis (study group; n = 76) with hearing gain achieved in a matched group (by age, sex, and degree of hypoacusis) of patients who had received a Schuknecht-type wire/Teflon prosthesis (control group; n = 70). All procedures had been performed by the authors at our institution between Jan. 2, 1994, and Dec. 31, 1997. Airway averages at low, medium, and high frequencies were estimated on the basis of pre- and postoperative audiologic evaluations, as were total air-bone gaps at 7 frequencies between 125 and 8,000 Hz. We found that the study group achieved a significantly greater degree of hearing gain at 125 and 250 Hz and significantly better closure of the air-bone gap at 250, 500, 1,000, 2,000, and 4,000 Hz. The hearing outcomes among patients in the study group were excellent.

[Realistic early and late results after otosclerosis surgery and presentation of a technique involving almost no complications]

Although the modern technique of otosclerosis surgery introduced by John Shea on 1st May 1956 has already been used throughout the world for almost fifty years it has not been possible to bring in line the differing opinions of surgeons concerning the optimum operation technique, the problems of the fenestration of the footplate, material and form of stapes replacement prosthetics and kind and place of their anchoring on the incus. Moreover, there is considerable disagreement among surgeons on a realistic evaluation of the findings of early and late results. During the last few decades otosclerosis surgery has become the hallmark of modern ear surgery and has been practiced in very highly specialized departments as well as in outpatient departments. The author, who has been very active in otosclerosis surgery since 1959-since 1979 with a modified personal technique-, wishes to prove that it is both meaningful and essential to modify the operation technique further, which is based on his own experiences and on more than 100 international publications. In this paper he presents his modified method, which has been tested on 1800 ears since 1979, as well as the results, achieved in this way.

A retrospective review of stapes surgery following introduction of 'reversal of the steps' technique

A retrospective study of 73 consecutive stapedotomies is reported. The technique of reversal of steps was achieved in 59% of cases. Closure of the air-bone gap to within 10 dB was achieved in 84% of the reversal group, and 81% of the standard technique group, with no statistically significant difference between the two groups.

Imaging of the postoperative middle ear

The aim of this article is twofold: (a) to present the principles and the indications of surgical treatment of middle ear pathologies; and (b) to review the imaging findings after middle ear surgery, including the normal postoperative aspects and imaging findings in patients presenting with unsatisfactory surgical results or with suspicion of postoperative complications. This review is intentionally restricted to the most common diseases involving the middle ear: chronic otitis media and otosclerosis. In these specific fields of interest, CT and MR imaging play a very important role in the postoperative follow-up and in the work-up of surgical failures and complications.

Revision stapes surgery: the malleus to oval window wire-piston technique

OBJECTIVE

To determine the effectiveness of the malleus to oval window wire-piston revision stapes surgery technique.

STUDY DESIGN

A retrospective analysis of 243 stapes procedures performed by the senior author over a 10-year period identified 15 revisions. Five patients underwent a malleus to oval window wire-piston technique. All patients were followed for at least 6 months. The surgical outcome including audiologic data and complications are noted.

METHODS

Stapes surgery was performed on an ambulatory basis by way of a transcanal approach under local anesthesia with monitored sedation by the same surgeon using a laser technique and a stapes wire-piston prosthesis.

RESULTS

Among revision stapes procedures, there was no significant difference in the air-bone gap closure or complication rate between the incus to oval window and the malleus to oval window techniques. The average preoperative air-bone gap in all revisions was 32 dB, whereas the mean postoperative gap was 10 dB hearing loss.

CONCLUSIONS

In experienced hands, revision stapes surgery using the malleus to oval window stapes wire-piston prosthesis is safe and effective.

Twenty-year review of revision stapedectomy

OBJECTIVE

To evaluate surgical findings and techniques, patient management techniques, and audiometric results of 522 revision stapedectomies.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary otologic referral center.

PATIENTS

A total of 522 revision stapedectomies over a 20-year period in Warren, Ohio, and Israel. The audiologic criterion for revision was an air-bone gap greater than 20 dB over the three-frequency range 0.5 to 2 kHz.

RESULTS

Of the 522 revision cases, a total of 483 patients were operated on to improve hearing. The remainder of the patients were operated on for various other noted reasons. Closure of the air-bone gap to within 10 dB was achieved in 71% of patients (343 of 483). The mean pure-tone average improvement was 17.8 dB, with an average postoperative air-bone gap of 7.3 dB. The most common surgical findings were prosthesis malfunction at the oval window, incus, or both (58%). Since beginning the use of the Argon laser for surgical problems, the success rate has increased to 80%. A subgroup of 35 Argon laser revision stapedectomies resulted in a larger hearing gain (25.2 dB) and 91.4% closure of the air-bone gap to less than 10 dB.

CONCLUSIONS

More than 70% of revision stapedectomy cases for hearing improvement have had successful closure of their air-bone gap. Since the introduction of the laser 5 years ago, the success rate has increased to 80%. In those specific cases where the laser was required, the success rate increased to 91.4%. Regardless of the revision technique, hearing results were the least successful when the incus could not be used for reconstruction.

The incudostapedial joint angle: implications for stapes surgery prosthesis selection and crimping

OBJECTIVE

To evaluate the role of the incudostapedial joint (ISJ) angle in stapes prosthesis size selection and crimping.

METHODS

The ISJ of 13 cadaveric human temporal bones were photographed, then measured using computer-aided design software. The relationship of ISJ angle to prosthesis length was modeled. A literature review evaluated factors contributing to stapedectomy failure.

RESULTS

The mean ISJ angle was 93.0 degrees (SD = 8.3 degrees ) (range, 75.0 degrees -104.0 degrees ). The mean ISJ angle deviation from 90 degrees was 7.35 degrees (SD = 4.45 degrees ) (range, 0.3 degrees -15.0 degrees ). The mean distance along the incus accessible for prosthesis placement was 3.21 mm (SD = 0.55 mm) (range, 2.00-4.00 mm).

CONCLUSIONS

Significant deviation of the ISJ angle from 90 degrees was found (P <.0001). The length along the incus accessible for prosthesis placement was sufficient to result in errors in prosthesis size selection and crimping with only small variations in the ISJ angle. Incorrect prosthesis sizing and crimping are frequently associated with stapedectomy failure. Variations in ISJ anatomy should be considered when selecting stapes prostheses lengths and may affect crimping technique.

Revision stapedectomy in Israel

OBJECTIVE

To evaluate the audiometric results and surgical findings of revision stapedectomy in Israel.

STUDY DESIGN

Retrospective. SETTING Tertiary referral center and private otology practice.

PATIENTS

Seventy-eight patients over 13 years.

RESULTS

A total of 78 patients were evaluated during a mean follow-up time of 1.5 years. Ten patients with far advanced otosclerosis or dizziness were then excluded. Closure of air-bone gap to within 10 dB was achieved in 67.6% of patients. Pure tone average (PTA, 500-4,000 Hz) improvement in hearing was 22.5 dB. Operative findings at time of revision were prosthesis malfunction (42.6%), incus necrosis (22%), incomplete stapedectomy (11.8%), and fistula (l.5%). Sensorineural hearing loss occurred in one patient. The technique of revision involved regrafting the oval window and the use of a piston prosthesis.

CONCLUSIONS

The surgical findings and results in this study are similar to those in other large studies. Although success was less than in primary stapedectomy, the results justified revisions. Hearing gains were dependent on surgical findings, the number of previous revisions, and associated ossicular problems.

Management of otosclerosis in the UK

The last 30 years has seen a gradual change in the management of otosclerosis. The aim of this study is to evaluate the current practice among British otolaryngology consultants using a questionnaire, and to compare it with the practice reported in a survey 8 years ago. A total of 353 valid responses (64.5%) were available for analysis. The overall trend is towards centralization, with a reduction in the number of surgeons undertaking stapes surgery (49.9%). The majority of consultants (81.3%) who undertake stapes surgery would operate for a unilateral conductive loss and 75.1% would undertake bilateral stapes surgery. Stapedotomy is the operation of choice (82%), with a few consultants performing partial or rarely total stapedectomies. Postoperative restrictions and follow-up times vary widely amongst surgeons, with the senior surgeons tending to be more conservative than the younger consultants.

Computed tomography and magnetic resonance imaging of pathologic conditions of the middle ear

Computed tomography (CT) is an excellent technique for demonstrating even small abnormalities of the thin and complex bony structures of the middle ear. For this reason, it is the modality of choice in the study of conductive hearing loss (CHL). However, not every patient complaining of CHL requires a CT study. In fact, established indications encompass complex conditions, such as the complications of acute and chronic otomastoiditis, the postoperative ear in chronic otomastoiditis or in the localization of prosthetic devices, and the assessment of congenital or vascular anomalies. Particularly, the precise extent of bone erosion associated with cholesteatoma is correctly demonstrated by high resolution CT. Conversely, although fistulization through the tegmen tympani or the posterior wall of temporal bone is usually detectable by CT, the actual involvement of meninges and veins are better assessed by magnetic resonance (MR). MR is also indicated when complicated inflammatory lesions are suspected to extend into the inner ear or towards the sigmoid sinus or jugular vein. Neoplasms arising from or extending into the middle ear require the use of both techniques as their combined data provide essential information. Most important data for surgical planning concern the destruction of thin bony structures and the relationships of the lesion with the dura and surrounding vessels. DSA and interventional vascular techniques maintain an essential role in the presurgical work-up and embolization of paragangliomas extended into the middle ear.

Malleostapedotomy in revision surgery for otosclerosis

PURPOSE

The purpose of this study was to analyze the results of malleostapedotomy and to compare them with those of a conventional incus stapedotomy in a series of 82 consecutive surgical revisions in otosclerotic patients.

MATERIALS AND METHODS

82 consecutive revision stapes surgery cases over 5 years were evaluated. The preoperative and postoperative audiometric data of 80 (97.5%) of the patients were obtained.

RESULTS

71 of the patients underwent a functional revision procedure as malleostapedotomy (56, 79%) or as incus stapedotomy (15, 21%). The most common cause of failure of primary surgery was a displaced or malfunctioning prosthesis (86.2%). Pathologic changes of the oval window were found in 80% of the cases. Problems of the incus were identified in 80% and abnormality of the malleus in 48.6% of the cases. The functional success rate of malleostapedotomy (closure within 10 dB) was found to be higher than that of traditional incus stapedotomy (p < 0.05). Overclosure was seen in 12 patients (17%) and a significant sensorineural hearing loss in 2 patients (3%). There were no dead ears in this series. The postoperative hearing results after first revision surgery were better than those after multiple surgical procedures (p < 0.05).

CONCLUSIONS

Malleostapedotomy yields better functional hearing results than incus stapedotomy in revision surgery for otosclerosis. The detection of many malleus fixations was the result of the systematic exposure of the anterior malleal process and ligament through an endaural approach with superior canaloplasty.

Short- and long-term results of stapedotomy and stapedectomy with a teflon-wire piston prosthesis

We analyzed the results of 604 cases of primary stapes surgery performed between 1974 and 1997 with replacement of the stapes by a 0.6- or 0.8-mm Schuknecht Teflon-wire piston. At long-term follow-up (1 to 21 years; mean, 7 years), the residual air-bone gap was 10 dB or less in 79% of the cases. The hearing results and postoperative complications were comparable to those reported by authors who used the same evaluation criteria. Although the aim of the surgery was to perform a small stapedotomy with a narrow footplate perforation (0.8 mm), a large stapedotomy or a stapedectomy was performed in 134 cases (22.2%) because of surgical or anatomic conditions. Our results show that the larger footplate perforations allowed a better correction of the air-bone gap at the lower frequencies. The ears with larger perforations did not show a higher incidence of sensorineural hearing loss.