Long-term Results of Troublesome CWD Cavity Reconstruction by Mastoid and Epitympanic Bony Obliteration (CWR-BOT) in Adults

A tailored approach in cholesteatoma surgery

PURPOSE

In recent years, new techniques have been added to cholesteatoma surgery, and established microsurgical approaches are being reconsidered. This study aims to present the importance of individualized decision-making for the selection of an intact canal wall (CWU) or canal wall down (CWD) surgical procedure for each patient.

METHODS

Using the "ChOLE" classification we categorized 264 operations retrospectively. 162 CWU and 102 CWD surgeries were performed. We focus to determine why a CWD procedure was chosen quite frequently despite some low-stage cases. Furthermore, we evaluated recidivism and hearing outcomes.

RESULTS

Smaller cholesteatomas (Ch-stage 1a, 1b & 2a) were found in 182 patients (70%), ossicular chain status feasible for straightforward reconstruction (O-stage 0, 1 & 2) was present in 186 patients (70%), minor complications due to the cholesteatoma (L-stage 1) were infrequent with 28 cases (11%) and a well-pneumatized mastoid was found in 144 cases (55%). Recidivism rates were low (7%) without any difference in both groups and a mean follow-up time of 4 years and 8 months. In primary surgeries there was a significant difference (p < 0.05) in postoperative mean air-bone gap (ABG) between CWU (17dB) and CWD (27dB).

CONCLUSION

The main goals of cholesteatoma surgery remain the avoidance of recidivism and optimal hearing rehabilitation. We recommend a tailored approach in the treatment of cholesteatomas and not a dogmatic one. Surgeons should not hesitate to perform a CWD procedure if required. Performed correctly it results in a dry ear and CWD surgery should remain in the skill set of the otologic surgeon.

Canal-wall up cholesteatoma surgery with mastoid obliteration leads to lower rates of disease recurrence without affecting hearing outcomes

Objectives

The primary objective was to determine whether obliteration of the epitympanic area and mastoid cavity during canal wall up (CWU) cholesteatoma surgery reduces the rate of recurrent and residual cholesteatoma compared to not obliterating the same area. The secondary objective was to compare postoperative hearing outcomes between both techniques.

Methods

A retrospective cohort study was conducted in a tertiary referral center. One-hundred-fourty-three ears were included of patients (≥18y) who underwent a CWU tympanomastoidectomy for cholesteatoma with or without bony obliteration between January 2015 and March 2020 in the University Medical Center Utrecht. The median follow-up was respectively 1.4 (IQR 1.1-2.2) vs. 2.0 years (IQR 1.2-3.1) (p = 0.013).

Interventions

All patients underwent CWU tympanomastoidectomy for cholesteatoma. For 73 ears bone dust, Bonalive® or a combination was used for obliteration of the mastoid and epitympanic area, the rest of the ears (n = 70) were not obliterated. In accordance with the Dutch protocol, included patients are planned to undergo an MRI scan with diffusion-weighted imaging (DWI) one, three and five years after surgery to detect recurrent or residual cholesteatoma.

Main outcome measures

The primary outcome measure was recurrent and residual cholesteatoma as evaluated by MRI-DWI and/or micro-otoscopy and confirmed by micro-otoscopy and/or revision surgery. The secondary outcome measure was the postoperative hearing.

Results

In this cohort, the group treated with canal wall up tympanomastoidectomy with subsequent bony obliteration (73 ears, 51.0%) had significantly lower recurrent (4.1%) and residual (6.8%) cholesteatoma rates than the group without obliteration (70 ears, 25.7% and 20.0%, respectively; p < 0.001). There was no significant difference between both groups in postoperative bone conduction thresholds (mean difference 2.7 dB, p = 0.221) as well as the mean air-bone gap closure 6 weeks after surgery (2.3 dB in the non-obliteration and 1.5 dB in the obliteration group, p = 0.903).

Conclusions

Based on our results, a canal wall up tympanomastoidectomy with bony obliteration is the treatment of choice, since the recurrent and residual disease rate is lower compared to the group without obliteration. The bony obliteration technique does not seem to affect the perceptive or conductive hearing results, as these are similar between both groups.

Surgical Treatment for Troublesome Mastoid Cavities: Canal Wall Reconstruction With Bony Obliteration Versus Subtotal Petrosectomy

INTRODUCTION

A chronically discharging modified radical mastoid cavity may require surgical intervention. We aim to explore two techniques.

OBJECTIVE

To compare outcomes of subtotal petrosectomy (STP) and canal wall reconstruction with bony obliteration technique (CWR-BOT).

STUDY DESIGN

Retrospective cohort study.

SETTING

A tertiary referral center.

PATIENTS

All patients with a chronically discharging mastoid cavity surgically treated at the Radboud University Medical Center by STP or CWR-BOT in 2015 to 2020, excluding patients with preoperative cholesteatoma.

MAIN OUTCOME MEASURES

Dry ear rate, audiometry, and rehabilitation.

SECONDARY OUTCOME MEASURES

Healing time, number of postoperative visits, complications, cholesteatoma, and need for revision surgeries.

RESULTS

Thirty-four (58%) patients underwent STP, and 25 (42%) CWR-BOT. A dry ear was established in 100% of patients (STP) and 87% (CWR-BOT). The air-bone gap (ABG) increased by 12 dB in STP, and decreased by 11 dB in CWR-BOT. Postoperative ABG of CWR-BOT patients was better when preoperative computed tomography imaging showed aerated middle ear aeration. ABG improvement was higher when ossicular chain reconstruction took place. Mean follow-up time was 32.5 months (STP) versus 40.5 months (CWR-BOT). Healing time was 1.2 months (STP) versus 4.1 months (CWR-BOT). The number of postoperative visits was 2.5 (STP) versus 5 (CWR-BOT). Cholesteatoma was found in 15% (STP) versus 4% (CWR-BOT) of patients. Complication rate was 18% (STP) and 24% (CWR-BOT) with a need for revision in 21% (STP) and 8% (CWR-BOT), including revisions for cholesteatoma.

CONCLUSION

STP and CWR-BOT are excellent treatment options for obtaining a dry ear in patients with a chronically discharging mastoid cavity. This article outlines essential contributing factors in counseling patients when opting for one or the other. Magnetic resonance imaging with diffusion-weighted imaging follow-up should be conducted at 3 and 5 years postoperatively.

Allograft bone vs. bioactive glass in rehabilitation of canal wall-down surgery

Canal wall-down (CWD) mastoidectomy creates a radical cavity that modifies the anatomy and physiology of the middle ear, thus preventing it from being self-cleaning and causing epidermal stagnation in the posterior cavities. Canal wall-down tympanomastoidectomy with reconstruction (CWDTwR) can obliterate such radical cavities. The main objective of this study was to compare postoperative results after CWDTwR by using either bone allografts or 45S5 bioactive glass as a filling tissue with an 18-month follow-up. This was a single-center observational trial including all patients undergoing CWDTwR. Patients were divided into two groups according to the filling material used: allograft bone (AB group) or 45S5 bioactive glass (BG group). Clinical monitoring was performed regularly, with control imaging performed at 18 months (CT scan and DW MRI). The two groups were compared with the t test for quantitative variables and the chi square test for qualitative variables (no revision surgery, audiometric results, complications, mastoid obliteration volume). Thirty-two patients underwent CWDTwR between October 2015 and 2018. The mean age was 48 years, and 71.9% (23/32) were men. A total of 46.9% (15/32) of the patients had undergone at least 3 middle-ear surgeries prior to CWDTwR. The most frequent preoperative symptom was otorrhea (100.0%, 32/32), and only 12.5% (4/32) experienced dizziness. Fifteen and 17 patients underwent surgery with bone allografts and 45S5 bioactive glass, respectively. At 18 months post-operation, 53.3% of the patients (8/15) in the AB group presented with recurrent otorrhea versus 5.9% (1/17) of patients in the BG group (p = 0.005). Seventy-eight percent (7/9) of symptomatic patients had undergone revision surgery at 18 months postoperation: 40.0% (6/15) in the AB group and 5.9% (1/17) in the BG group (p = 0.033). One patient's surgery was cancelled due to the COVID-19 pandemic, and one patient refused surgery. The effects of CWDTwR with bone allografts are disappointing in early follow-up, with significant resorption leading to a 40.0% revision surgery rate. 45S5 BG is a simple solution, with preliminary results that are superior to those of AB. However, prospective controlled studies with longer follow-up times are needed to evaluate the value of BG versus other synthetic materials (such as hydroxyapatite) in surgical management of CWDTwR.Trial registration: retrospectively registered.

Efficacy of S53P4 Bioactive Glass for the Secondary Obliteration of Chronically Discharging Radical Cavities

Objective

Present the results of the secondary obliteration of chronically discharging radical cavities using S53P4 bioactive glass (BAG).

Study Design

Retrospective cohort study.

Setting

Single-center study.

Methods

A single-center retrospective cohort study was conducted of all patients that underwent secondary obliteration of persistently draining radical cavities using S53P4 BAG between 2011 and 2022. Patients with middle ear cholesteatoma were excluded. The main outcome was postoperative otorrhea, as indicated by Merchant grading.

Results

In total, 97 patients were included. The median postoperative follow-up time was 3.9 years (range 0.5-10.4). Average time between the original canal wall down surgery and the secondary obliteration was 25.3 years (SD 11.7, range 2-66). At the most recent follow-up visit, a Merchant grade of 0 to 1 was observed in 95% of the cases. There were no cases of sensorineural hearing loss or facial palsy, one case developed a retro auricular skin defect and 1 patient developed CSF leakage. Minor complications were seen in 10 patients (10%). Ossicular chain reconstruction with a titanium prosthesis was performed in 42 cases, resulting in a median improvement of 11.2 dB in air conduction thresholds. In 9/42 cases (21%), closure of the postoperative air-bone gap to ≤20 dB was achieved. Twenty-five percent of cases could be discharged from out-patient visits.

Conclusion

Revision of persistently draining radical cavities with BAG obliteration is feasible and results in a dry and safe ear in 95% of the patients, thereby enabling wearing of a conventional hearing aid. Out-patient visits could be ceased in 25% of the cases.

The effect of bony obliteration on quality of life after tympano-mastoidectomy surgery: A prospective observational controlled cohort study

Objectives

The study's primary objective was to compare the quality of life (QoL) and external auditory canal (EAC) hygiene among patients who underwent bony mastoid obliteration or meatoplasty after canal wall down (CWD) mastoidectomy.

Methods

A prospective, observational, controlled cohort study was conducted at our tertiary referral university hospital. Twenty-eight patients older than 16 years of age with chronic otitis media who underwent CWD mastoidectomy were included. Two cohorts were followed: CWD mastoidectomy followed by mastoid obliteration (Group 1, n = 14) and CWD mastoidectomy followed by meatoplasty (Group 2, n = 14). The main outcome measures of total COMBI score (postoperative 6-month QoL) and EAC hygiene were compared between the groups.

Results

The average age of the patients was 36.14 (12. 22) years; 15 (53.6%) were female and 13 (46.4%) were male. There were no differences in demographic variables, preoperative findings, or COMQ-12 (preoperative QoL) scores between groups. The average COMBI score of Group 1 (49.0 [8.66]) was not significantly different from Group 2 (46.79 [7.76]) (p = .482). Poor EAC hygiene was observed in eight (57.1%) patients in Group 2 and three (21.4%) patients in Group 1 (p = .06). In Group 1, no resorption of graft material was observed in 10 (71.4%) patients, minor resorption was observed in three (21.4%) patients, and significant resorption was observed in one (7.1%) patient. There were no significant differences in audiological findings between groups (p > .05).

Conclusion

There were no significant differences regarding short-term postoperative QoL, EAC hygiene, or hearing outcomes between patients who underwent bony mastoid obliteration or meatoplasty after CWD mastoidectomy.

Level of Evidence

1b (individual prospective cohort study).

Mastoid obliteration and canal wall reconstruction with posterior auricular artery (PAA) fascia-periosteum flap

OBJECTIVE

Unstable cavities are defined as cavities with cerumen accumulation that need frequent cavity cleaning in the out-patient clinic, cavities that are intolerant to water due to risk of infection or that are subject to frequent infection and otorrhoea. The objective of this study is to address the problem of troublesome mastoid cavities, with the performance of secondary mastoid obliteration and canal wall reconstruction, using a novel posterior auricular artery (PAA) fascia-periosteum flap.

MATERIALS AND METHODS

A prospective study was designed, only secondary obliterations were included. Unstable mastoid cavities were defined as Merchant grade 2 or 3 and were included for surgery.

RESULTS

At 12 months of follow up, a complete external auditory canal (EAC) and a self-cleaning ear were achieved in all 23 patients. Completely dry ears were achieved in 21 patients (91.3%). An air-bone gap improvement of 5dB was achieved.

CONCLUSION

Mastoid obliteration and EAC reconstruction are effective procedures to treat troublesome post canal wall down mastoid cavities. They improve quality of life and enable patients to overcome ear discharge. A standard EAC size enables the utilization of conventional hearing aids, it also reduces the need for constant mastoid cleaning and decreases healthcare expenses. The PAA flap seems to be an effective procedure to achieve all these features, as it is used to obliterate the mastoid and becomes a structural component of the neo-EAC.

Assessing the Prognostic Value of the ChOLE Classification in Predicting the Severity of Acquired Cholesteatoma

OBJECTIVE

To assess the prognostic value of the ChOLE classification in predicting the severity of acquired cholesteatoma.

METHOD

A retrospective chart review of patients undergoing primary cholesteatoma surgery in our tertiary referral center. The primary outcome measures were analyzed in three groups of follow up (FU): residual cholesteatoma in group A, FU > 52 weeks after last-look surgery or MRI-DWI; recurrent cholesteatoma in group B, FU > 52 weeks after last outpatient visit; and adverse events (AE) in group C, FU > 12 weeks after surgery. Cholesteatomata were staged according to the ChOLE classification. Kaplan-Meier curves were used to determine the prognostic value of the classification in predicting cholesteatoma severity, while correcting for FU.

RESULTS

No significant differences were observed between the various stages of the ChOLE classification and residual or recurrent cholesteatoma rate, nor the occurrence of AE. Cholesteatoma extension to the sinus tympani or widespread in the mastoid, as well as absence of the stapes superstructure were predictive of residual disease. Sclerotic mastoids had a lower risk of residual disease than mastoids with good or poor pneumatization and ventilation. Poorly ventilated and poorly pneumatized mastoids were associated with increased risk of recurrence. Widespread cholesteatoma in the mastoid as well as presence of preoperative extracranial complications were correlated with an increased risk of AE.

CONCLUSION

The ChOLE classification does not predict residual nor recurrent disease, nor the occurrence of AE, in our study population. Risk factors for severe cholesteatoma were identified, potentially useful for the development of future classifications.

Revision surgery for chronically discharging mastoid cavities: mastoid obliteration with canal wall reconstruction versus non-obliteration surgery

Purpose

To evaluate the surgical results of revision canal wall down (CWD) surgery for chronically discharging mastoid cavities and to compare the non-obliteration approach to mastoid obliteration with canal wall reconstruction.

Methods

This is a retrospective cohort study. All adult patients (≥ 18 years) who underwent revision surgery for chronically draining mastoid cavities between January 2013 and January 2020 were included. Primary outcome measures included the dry ear rate, complications and postoperative hearing.

Results

79 ears were included; 56 ears received revision CWD with mastoid obliteration and posterior canal wall reconstruction and 23 ears received CWD without mastoid obliteration. The dry ear rate at the most recent outpatient clinic visit (median 28.0 months postoperative) was significantly higher in the obliteration group with 96.4% compared to 73.9% for the non-obliteration group (p = .002). There were no differences in audiological outcome and incidence of complications between the two techniques.

Conclusion

We show that in our study population revision CWD surgery with mastoid obliteration and posterior canal wall reconstruction is superior to revision CWD surgery without mastoid obliteration in the management of chronically discharging mastoid cavities. In the obliteration group, a dry ear was achieved in 96.4% as this was 73.9% in the non-obliteration group. We found no differences in audiological outcome and in incidence of complications between the two techniques.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-07138-0.

Bioactive glass in canal wall reconstruction tympanoplasty

The purpose of this Technical Note is to describe the surgical technique to transform canal wall down tympanoplasty into canal wall up tympanoplasty, that is, to rehabilitate a recess cavity by filling the mastoid and epitympanic cavities with synthetic tissue (bioactive glass) and recreating a normal-caliber external auditory canal. Mastoid cavity obliteration leads to a clinically significant improvement in health-related quality of life without increasing risk of recurrent or residual cholesteatoma, conditional upon technically impeccable surgery.

Cartilage tympanoplasty for recurrent cholesteatoma using a single sliced cartilage graft: Our experience in 14 ears

Our procedure may provide a useful alternative in cases where previous surgeries have failed to eradicate the cholesteatoma.

[Obliteration of the middle ear cavity in children: the current state of the problem and our first experience]

Chronic otitis media is one of the most common ear pathologies among children. This article provides a short overview of publications on surgical techniques. Currently, the most effective treatment is the surgical sanitation of the middle ear cavities. There are two fundamentally different approaches of operations in relation to the posterior wall of the external auditory canal - «open» and «closed» types. Both methods have their advantages and disadvantages, which are especially noticeable in pediatric revision otosurgery. Surgical obliteration of the sanitized middle ear cavities is an effective compromise option. However, the techniques of bone obliteration, which are actively applied among adults, are difficult if we discuss children ear. A way out of this situation may be the use of modern osteoplastic materials for filling large trepanation cavities. The article describes in detail the technique of revision sanitizing surgery on the middle ear using osteoplastic granules. Purpose of the study. The analysis of the first results of separate obliteration of paratympanic cavities in children using osteoplastic materials.

MATERIAL AND METHODS

In the period from May 2018 to November 2020, on the basis of the Federal State Autonomous Institution «National Medical Research Center of Children's Health» of the Ministry of Health of Russia, 28 children aged from 6 to 17-year-old with chronic otitis media and cholesteatoma were operated using osteoplastic obliteration, who had previously sanitizing operation on the middle ear. All children on admission to the hospital and 6-12 months after the operation underwent a complex examination. The condition of each patient was assessed using the OMO-22 quality of life questionnaire, to which the parents answered the questions twice - before and 1 year after surgery.

RESULTS

During the postoperative period none of the patients had clinical signs of recurrence of cholesteatoma, which was confirmed by CT scan. When assessing the quality of life of children using a questionnaire, the average score before the operation was 130.2±27.7, after the operation - 61.5±21.1. The indicator of the bone-air interval before surgery in patients averaged 29.8±9.7 dB, 1 year after surgery - 13.0±10.9 dB (p>0.05).

FINDINGS

The first experience of using osteoplastic materials for obliterating the paratympanic spaces in children has shown high efficiency, ease of use and safety.

Repair effect of xenogeneic acellular dermal matrix during external auditory canal reconstruction after canal wall down mastoidectomy

Background: In some cases, there is insufficient external auditory canal (EAC) skin to cover the reconstructed canal wall after canal wall down (CWD) mastoidectomy. Acellular dermal matrix (ADM) can help to repair the skin, mucosa and other epidermal tissue defects.Aims: To investigate the repair effect of xenogeneic ADM (xeno-ADM) for EAC skin defects.Material and Methods: We retrospectively analyzed 28 patients who underwent open mastoidectomy combined with canal wall reconstruction and mastoid obliteration in our hospital. The xeno-ADM was used to repair the EAC skin defect. The epithelialization time, dressing change times, complications and hearing improvement post-operation were summarized and analyzed.Results: Reasons for using xeno-ADM included: 11 (39.3%) cases suffered from extensive middle ear cholesteatoma, three (10.7%) cases suffered from advanced EAC cholesteatoma, eight (28.6%) cases to solve the cavity-related problems, and six (21.4%) patients had a narrow EAC. The postoperative epithelialization time was 5.8 ± 1.6 weeks, and the number of dressing changes was 4.8 ± 1.6 times. There was no xeno-ADM rejection and related complications, the postoperative hearing improvement was statistically significant (p = .013).Conclusions and Significance: Xeno-ADM could be a safe, effective and simple method for repairing skin defect in the reconstruction of EAC after CWD mastoidectomy.

[The results of surgical ablation of parathympanic spaces in the patients presenting with cholesteatoma]

INTRODUCTION

On the one hand, open-type surgical modalities have the advantage of the low frequency of relapses; on the other hand, they lead to the undesirable changes in the anatomical and physiological characteristics of the ear that in the long run create serious problems for both the doctor and the patient. In contrast, the closed-type surgical interventions are associated with a more favourable hygienic status and functional outcome but create a high risk of development of recurrent and residual cholesteatomas. The disadvantages of both types of cholesteatoma surgery motivated the surgeons for the development of the 'hybrid' approaches combining the advantages of open and closed strategies. The obliteration of the paratympanic spaces is one of them.

AIM

The objective of the present study was to evaluate the results of the surgical treatment of recurrent and residual cholesteatomas and to optimize the algorithm of the postoperative control with the use of MRI in the non-EPI DWI regime.

MATERIAL AND METHODS

The retrospective analysis of the available clinical materials covering the period from 2009 to 2014 included the results of the surgical treatment of the patients suffering from chronic otitis media and cholesteatoma with the use of the method for the obliteration of the paratympanic spaces.

RESULTS

A total of 179 patients were operated using the obliteration technique. The patients were under observation for 34 months on the average. We used the otomicroscopy and MRI in the non-EPI DWI regime to examine the patients within 1, 2, and 3 years after surgery. The residual cholesteatoma was discovered in 15 (8.4%) patients out of the total 179 ones. The cases of recurrence of the cholesteatomas were not observed. The diagnostic effectiveness of MRI in the non-EPI DWI regime was estimated for the purpose of the postoperative control. Sensitivity of the method was 93.3%, specificity - 97.1%.

Surgical treatment of chronic ear disease in remote or resource-constrained environments

Background

Surgery for chronic suppurative otitis media performed in low- and middle-income countries creates specific challenges. This paper describes the equipment and a variety of techniques that we find best suited to these conditions. These have been used over many years in remote areas of Nepal.

Results and conclusion

Extensive chronic suppurative otitis media is frequently encountered, with limited pre-operative investigation or treatment possible. Techniques learnt in better-resourced settings with good follow up need to be modified. The paper describes surgical methods suitable for resource-poor conditions, with rationales. These include methods of tympanoplasty for subtotal wet perforations, hearing reconstruction in wet ears and open cavities, large aural polyps, and canal wall down mastoidectomy with cavity obliteration. Various types of autologous ossiculoplasty are described in detail for use in the absence of prostheses. The following topics are discussed: decision-making for surgery on wet or best hearing ears, children, bilateral surgery, working with local anaesthesia, and obtaining adequate consent in this environment.

A new theory interprets the development of a retraction pocket as a natural self-healing process

PURPOSE

The thesis that cholesteatoma evolves from a retraction pocket is widely accepted today. Yet, its prime etiology, the question of what triggers the invagination of healthy skin, still remains unclear despite centuries of investigations into the origin of cholesteatoma. A new idea interprets the horizontal migration of skin into the middle ear cavities as a self-healing process, curing an underlying inflammation in the tympanic cavity, through the overgrowth and contact with immunologically active tissue.

METHODS

A retrospective analysis of the interrelation of retraction pockets and underlying granulation tissue was conducted in 209 second-look cholesteatoma surgeries over the last decade.

RESULTS

A stable tympanic membrane over aerated, healthy middle ear mucosa was found in 71.3% of cases. In 11%, small retractions with air in other parts of the middle ear cleft (epitympanic, sinus or anterior mesotympanum) were described. In 6.2%, granulations under a retraction were found. Only 3.8% of the reports revealed air behind a retraction or did not provide enough information on the mucosa situation behind the drum membrane.

CONCLUSIONS

A new hypothesis interprets the origin of a retraction pocket-the precursor of a cholesteatoma-as a natural attempt by the body to cure an underlying inflammation in a cavity. Analogous phenomena exist, e.g. the migration of the omentum towards a local inflammation in the abdomen. This idea, which is supported by the findings in our 209 second-look surgeries, is the first explanation of the origin of retraction pockets that is compatible with the various characteristics of original or recurrent cholesteatoma. A prophylaxis against a recurrent cholesteatoma might be attained by securing free drainage of the mucosa into the tubal orifice with the use of thin silicone foils in an attempt to prevent any granulation in the middle ear cleft, similar to the principles of modern rhinosinusoidal surgery with its emphasis on unblocked mucosa clearance. This allows gas production in the healed middle ear mucosa to recover, reducing the risk of a recurrent retraction.

Anatomy and Surgical Approach of the Ear and Temporal Bone

The temporal bone is one of the more complex structures at the skull base that houses the hearing and vestibular organs, numerous nerves, and vessels. A host of inflammatory and neoplastic processes can occur within the temporal bone that often necessitate permanent and frozen section pathologic examination. A number of simple to complex surgical procedures are used to manage temporal bone pathology. This chapter will provide a brief overview of normal temporal bone anatomy, common surgical approaches, normal histology, and indications for pathologic examination.

Surgical results of modified canal wall down tympanoplasty

CONCLUSION

Patients with mastoiditis and chronic suppurative otitis media which has small mastoids that make them ideal candidates for modified canal wall down mastoidectomy (MCWD) which contributes to a dry and spacious ear and the maintaining and improving hearing.

OBJECTIVES

To evaluate surgical outcomes for chronic otitis media underwent MCWD.

METHODS

A clinical retrospective study was performed on 47 ears with chronic otitis media which has relatively limited attic lesions have the small, sclerotic and hypocellular mastoids according to the preoperative high-resolution CT scan of the temporal bone that underwent MCWD and 32 ears with typical canal wall down operation form January 2010 to January 2016.

RESULTS

In the MCWD group, the mean preoperative air conduction (AC) threshold of 38.2 ± 1.1 dB was lowered to 31.0 ± 0.8 dB postoperatively (p < .01). The mean pre- and postoperative air-bone gaps (ABG) of all patients were 16.0 ± 1.0 dB and 9.6 ± 0.8 dB, respectively. In the canal wall down group, the mean preoperative AC threshold of 37.2 ± 1.0 dB was lowered to 32.8 ± 0.9 dB postoperatively (p < .01). The mean pre- and postoperative air-bone gap was reduced with 4.4 ± 0.4 dB (p < .01). There was statistical difference in hearing improvement between the modified canal wall down and the canal wall down group (p < .05).