Cochlear Implantation in Otosclerosis

Endoscopic-Assisted Cochlear Implantation in Far Advanced Otosclerosis

OBJECTIVES

To evaluate the effectiveness of cochlear implantation (CI) in case of far advanced otosclerosis and to evaluate the value of using intraoperative otoendoscopy to facilitate the identification of the round window membrane and the scala tympani without the need to remove the posterior canal wall or to perform a subtotal petrosectomy.

STUDY DESIGN

Retrospective case-series study.

SETTING

Tertiary academic CI center.

PATIENTS AND METHODS

This study was conducted on patients with far advanced otosclerosis who underwent endoscopic-assisted CI between January 2010 and June 2020 at the same CI center. The minimum follow-up period was 2 years after surgery.

RESULTS

Fourteen patients were included in the study. Ten patients had undergone a previous stapedotomy. Electrode insertion in the scala tympani was successfully accomplished in all cases included in the study. There was a statistically significant improvement in pure-tone average and speech discrimination scores in all cases of the study group (p < 0.0001). There were no statistically significant differences in postoperative pure-tone average or speech discrimination scores between cases with and without cochlear ossification or between cases with and without a previous stapedotomy (p > 0.05).

CONCLUSION

Endoscopic-assisted CI is an effective option for hearing restoration in patients with far advanced otosclerosis. Otoendoscopy can facilitate visualization and access to the scala tympani without the need to remove the posterior canal wall or to perform a subtotal petrosectomy.

Cochlear Implants after Meningitis and Otosclerosis: A Comparison between Cochlear Ossification and Speech Perception Tests

(1) Background: Performance after Cochlear Implantation (CI) can vary depending on numerous factors. This study aims to investigate how meningitis or otosclerosis can influence CI performance. (2) Methods: Retrospective analysis of CI performance in patients with etiological diagnosis of meningitis or otosclerosis, comparing the etiologies and analyzing the image findings, along with electrode array insertion status and technique. (3) Results: Speech recognition in CI patients with otosclerosis improves faster than in patients with meningitis. Other features such as radiological findings, degree of cochlear ossification, surgical technique used and total or partial insertion of electrodes do not seem to be directly related to speech recognition test performance. (4) Conclusions: Patients should be warned that their postoperative results have a strong correlation with the disease that caused their hearing loss and that, in cases of meningitis, a longer duration of speech-language training may be necessary to reach satisfactory results.

The Clinical Picture of Otosclerosis and the Surgery Effect on Bone Conduction Thresholds on Audiograms

Our study aims to illustrate the clinical picture of otosclerosis in patients and the effect of surgery on the bone conduction thresholds compared to audiometry tests before surgery. A retrospective study included 36 patients that fit the inclusion criteria based on the patient's files and Pure Tone Audiometry of the patients before and after surgery. The questionnaire used is attached at the end of the study. According to Our sample, 77.8% were females, and 22.2% were males. The youngest was 17 years old, the eldest was 61, and the mean age was 38.2 years old. Hearing loss was the most common symptom in 100% of patients, while tinnitus was found in 66.7% and vertigo in 11%. The Injury was bilateral in 72% of the cases. Before surgery, the mean air conduction threshold (ACT) was 54.7 dB, the mean value of the air-bone gap (ABG) was 38.3 dB, and the mean bone conduction threshold (BCT) was 16.1 dB. Meanwhile, after the surgery, the mean BCT was 18.2 dB. Otosclerosis is more common in middle-aged females. Most cases are bilateral. Two-thirds of the cases of hearing loss were associated with tinnitus, while only a few had vertigo. A slight increase was noticed in BCTs after surgeries, especially at 4000 Hz. Stapedectomy caused a noticeable decrease in the values of BCTs on the frequency 4000 Hz. Stapedotomy improved the BCTs after surgery by about 5.3 dB at 4000 Hz.

Risk factors and management strategies of inadvertent facial nerve stimulation in cochlear implant recipients: A systematic review

Objectives

To systematically review the prevalence and risk factors of inadvertent facial nerve stimulation (FNS) after cochlear implant (CI) surgery. And to report the different management strategies used for reducing and resolving FNS.

Data Source

Web of Science, Scopus, PubMed, Cochrane Library, and Virtual Health Library (VHL) of the World Health Organization (WHO).

Review Methods

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) on studies that reported FNS as a complication after CI. A comprehensive electronic search strategy was used to identify the relevant articles. We extracted the data on the prevalence of FNS after CI activation, the reported grades, and the management strategies. The number of associated electrodes; cause of deafness; co-anomalies; and duration of hearing loss and their relationships with FNS were also studied.

Results

Twenty-one relevant articles were included in this review. The prevalence of FNS among the CI populations was 5.29% (175/3306 patients). Among those whose ages were reported, 58.3% (95/163) were adults, and 41.7% (68/163) were pediatrics. Modifying the different fitting parameters was the most used strategy, as it successfully resolved FNS in 85.5% of the patients (142/166). The second commonly used management strategy was surgical intervention (reimplantation or explantation), which was reported in seven studies for 23 patients.

Conclusion

FNS after CI activation could be controlled and resolved with many advances that range from readjusting the fitting parameters to surgical intervention. However, further studies are required to validate the efficacy of each management strategy and its impact on patients' performance. Our findings demonstrate that CI recipients with FNS could still benefit from the CI devices and their FNS could be controlled.

Stapes Surgery in Far-Advanced Otosclerosis

INTRODUCTION

Surgical treatment of patients with far-advanced otosclerosis (FAO) has not yet been standardized. Patients with FAO are the candidates for stapes surgery or cochlear implant (CI). Although many surgeons consider stapes surgery as the first choice, other authors prefer CI because of the excellent hearing results.

OBJECTIVE

The authors discuss their experience in the treatment of patients with FAO, potentially candidates for CI, who underwent stapedotomy.

MATERIALS AND METHODS

Eleven adult patients with FAO underwent stapedotomy from 2006 to 2016. Pure-tone average (PTA) between 0.5-1-2-3 kHz and speech perception test with hearing aids were determined before and after stapedotomy.

RESULTS

The results show a statistically significant improvement in air condition threshold (PTA) and satisfactory results with regard to speech recognition in 9 (81.8%) cases. Postoperative results are not influenced by the type of stapedotomy prosthesis employed and do not change during follow-up (3 years).

CONCLUSIONS

The authors suggest first performing stapes surgery in patients with FAO and reserving CI in case of failure.

Cochlear re-implantation with the use of multi-mode grounding associated with anodic monophasic pulses to manage abnormal facial nerve stimulation

Objectives: To investigate the outcomes of cochlear re-implantation using multi-mode grounding stimulation associated with anodic monophasic pulses to manage abnormal facial nerve stimulation (AFNS) in cochlear implant (CI) recipients. Methods: Retrospective case report. An adult CI recipient with severe AFNS and decrease in auditory performance was re-implanted with a new CI device to change the pulse shape and stimulation mode. Patient's speech perception scores and AFNS were compared before and after cochlear re-implantation, using monopolar stimulation associated with cathodic biphasic pulses and multi-mode stimulation mode associated to anodic monophasic pulses, respectively. The insertion depth angle and the electrode-nerve distances were also investigated, before and after cochlear re-implantation. Results: AFNS was resolved, and the speech recognition scores rapidly increased in the first year after cochlear re-implantation while remaining stable. After cochlear re-implantation, the e15 and e20 electrodes showed shorter electrode-nerve distances compared to their correspondent e4 and e7 electrodes, which induced AFNS in the first implantation. Conclusions: Cochlear re-implantation with multi-mode grounding stimulation associated with anodic monophasic pulses was an effective strategy for managing AFNS. The patient's speech perception scores rapidly improved and AFNS was not detected four years after cochlear re-implantation.

Facial nerve stimulation in adult cochlear implant recipients with far advanced otosclerosis

Objectives

The objective of this study was to predict occurrence of facial nerve stimulation (FNS) in cochlear implanted patients for far-advanced otosclerosis (FAO) by correlating preoperative computed tomography (CT)-scan data to FNS and to evaluate FNS impact on hearing outcomes.

Methods

Retrospective analysis on 91 ears (76 patients) implanted for FAO. Electrodes were straight (50%) or perimodiolar (50%). Demographic data, extension of otosclerosis on preoperative CT scan, occurrence of FNS, and speech performance were analyzed.

Results

Prevalence of FNS was 21% (19 ears). FNS appeared during the first month (21%), 1-6 months (26%), 6-12 months (21%), and over 1 year (32%) postimplantation. Cumulative incidence of FNS at 15 years was 33% (95% CI = [14-47%]). Extension of otosclerotic lesions on preimplantation CT-scan was more severe in FNS ears compared to No-FNS (p < .05): for Stage III, 13/19 (68%) and 18/72 (25%) ears for FNS and No-FNS groups, respectively (p < .05). Location of otosclerotic lesions relative to the facial nerve canal was similar whatever the presence or not of FNS. Electrode array had no impact on FNS occurrence. At 1 year post-implantation, duration of profound hearing loss (≥5 years) and previous stapedotomy were negatively associated with speech performance. FNS did not impact hearing outcomes, despite a lower percentage of activated electrodes (p < .01) in the FNS group. Nevertheless, FNS were associated with a decrease of speech performance both in quiet (p < .001) and in noise (p < .05).

Conclusion

Cochlear implanted patients for FAO are at greater risk of developing FNS affecting speech performance over time, probably due to a higher percentage of deactivated electrodes. High resolution CT-scan is an essential tool allowing FNS prediction but not time of onset.

Level of evidence

2b, Laryngoscope Investigative Otolaryngology, 2022.

Cochlear Implantation in Far Advanced Otosclerosis: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate speech outcomes and facial nerve stimulation (FNS) rates in patients with far advanced otosclerosis (FAO) after cochlear implantation.

METHODS

A systematic review was performed using standardized methodology of Medline, EMBASE, PubMed, Cochrane, and Web of Science databases. Studies were included if adults with FAO underwent cochlear implantation. Exclusion criteria included concurrent otologic history (e.g., Meniere's disease, superior canal dehiscence), non-English-speaking implant users, case reports, abstracts, and letters/commentaries. Bias was assessed using the Newcastle-Ottawa Scale for cohort studies and the National Institute of Health Scale for case series. The primary outcome measure was speech discrimination and the secondary outcomes were rates of partial insertion and FNS.

RESULTS

Twenty-seven studies evaluated cochlear implantation in FAO. Due to the heterogeneity of testing methods, statistical pooling of speech discrimination was not feasible, but qualitative synthesis indicated a positive effect of implantation. Pooled rates of FNS were 18% (95% confidence interval, CI 12%-27%) and the rate of partial insertion was 10% (95% CI 7%-15%).

CONCLUSION

Cochlear implantation in FAO demonstrates significant gains in speech discrimination scores with higher rates of FNS and partial insertion. Laryngoscope, 2022.

Cochlear Implant Outcomes in Patients With Otosclerosis: A Systematic Review

OBJECTIVE

This study aimed to establish hearing outcomes after cochlear implantation in patients with otosclerosis.

MATERIALS AND METHODS

We conducted a systematic review and narrative synthesis. Databases searched were as follows: MEDLINE, PubMed, Embase, Web of Science, Cochrane Collection, and ClinicalTrials.gov . No limits were placed on language or year of publication. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

RESULTS

Searches identified 474 abstracts and 180 full texts, with 68 studies meeting the inclusion criteria and reporting outcomes in a minimum of 481 patients with at least 516 implants. Patient-reported outcome measures (PROMs) were reported in five studies involving 51 patients. Intraoperative adverse events/surgical approach details and preoperative radiological assessment were reported in 46 and 38 studies, respectively. The methodological quality of included studies was modest, predominantly consisting of case reports and noncontrolled case series with small numbers of patients. Most studies were Oxford Centre for Evidence Based Medicine grade IV.

DISCUSSION

Access to good rehabilitation support is essential to achieving the good hearing outcomes and PROMs that can be expected by 12 months after implantation in most cases. There was a significant association between the radiological severity of otosclerosis and an increase in surgical and postoperative complications. Postoperative facial nerve stimulation can occur and may require deactivation of electrodes and subsequent hearing detriment.

CONCLUSIONS

Hearing outcomes are typically good, but patients should be counseled on associated surgical complications that may compromise hearing. Modern diagnostic techniques may help to identify potentially difficult cases to aid operative planning and patient counseling. Further work is needed to characterize PROMs in this population.

Cochlear Implantation in Advanced Otosclerosis: Pitfalls and Successes

Purpose of Review

This review will highlight recent outcome-based evidence guiding decision making for cochlear implantation in advanced otosclerosis, related complications, and technical surgical considerations in otosclerosis and the obstructed cochlea.

Recent Findings

Cochlear implantation in advanced otosclerosis results in consistent, excellent auditory outcomes with improvement in both objective speech recognition scores and subjective quality of life measures. Facial nerve stimulation may occur at higher rates in otosclerosis cochlear implant recipients. Cochlear implantation in the setting of luminal obstruction in osteosclerotic patients may be managed with altered surgical technique to achieve successful auditory improvements. Pre-operative imaging with high resolution CT or MRI may help anticipate intraoperative challenges and post-operative complications in cochlear implantation.

Summary

Cochlear implantation is an established, successful treatment for profound hearing loss in advanced otosclerosis. Surgeon knowledge of outcomes, complications, and potential surgical challenges is important to appropriately counsel patients regarding auditory rehabilitation options in advanced otosclerosis.

Cochlear implantation outcomes in patients with otosclerosis: a single-centre study

PURPOSE

To analyse surgical and auditory outcomes after cochlear implantation in otosclerosis and to compare them to the outcomes in patients with post-lingual hearing loss with different aetiology.

METHODS

Medical records of 17 subjects (22 ears) diagnosed with otosclerosis were compared to 21 controls (25 ears) matched by age, sex, duration of hearing loss and experience with cochlear implant in years. Demographic characteristics, surgical complications, facial nerve stimulation, number and reason for deactivated electrodes and auditory outcome (monosyllabic word score) were analysed. The auditory outcome was further evaluated according to the anatomical localisation of the otosclerotic lesions (grades) and compared between patients with active and deactivated electrodes.

RESULTS

Otosclerotic patients showed similar surgical outcome in comparison to the controls. A low frequency (13.6%) of facial nerve stimulation was observed in otosclerosis. A significantly higher (p = 0.014) number of deactivated electrodes (4.3%) in subjects with otosclerosis in comparison to non-otosclerosis patients (1.6%) was found. A trend of less speech discrimination of monosyllabic words (65%) in otosclerosis than in non-otosclerosis patients (80%) (p = 0.109) and no difference in the postoperative auditory assessment with regard to the disease grade and electrode disabling was found.

CONCLUSIONS

Cochlear implantation by otosclerosis provides excellent auditory outcome with a low rate of surgical complications. Alteration in fitting strategy as electrodes disabling is frequently needed to overcome complications as incomplete insertion, facial nerve stimulation and poor sound quality.

Cochlear implantation among patients with otosclerosis: a systematic review of clinical characteristics and outcomes

PURPOSE

There have been considerable advancements in cochlear implants in different clinical scenarios; however, their use in patients with otosclerosis remains challenging. This review aimed to investigate the surgical and clinical outcomes of cochlear implantation in patients with otosclerosis.

METHODS

An electronic literature search was performed using four main databases through February 2021 to identify original studies of cochlear implantation in patients with otosclerosis for inclusion in this systematic review. The study protocol was registered with the Prospectively Registered Systematic Reviews and Meta-analyses (reference number: CRD42021234753).

RESULTS

A total of 23 studies including 3162 patients were enrolled. Of these patients, only 392 had otosclerosis and underwent cochlear implantation. The duration of deafness was reported in only eight studies, extending up to 50 years. Far-advanced otosclerosis was observed in 153 patients. A total of 56 patients used hearing aids. Stapedectomy and stapedotomy were performed in 118 and 63 patients, respectively. In three studies, the temporary success of stapedectomy and stapedotomy was 6 (43%) and 5 (71%) patients, respectively. Computed tomography was used as a preoperative assessment tool in most studies (n = 14, 60.9%). Incomplete implant insertion occurred in 17 patients, while facial nerve stimulation occurred in 36 patients after implantation.

CONCLUSION

Cochlear implantation is a relatively safe modality that can provide promising audiological outcomes in patients with otosclerosis. However, several factors, including cochlear ossification, duration of deafness, and previous operations, can affect its outcomes. Further studies with a larger sample population are recommended.

Familial Otosclerosis Associated with Osteogenesis Imperfecta: A Case Report

Otosclerosis, a hereditary disorder characterized by disordered resorption and deposition of bone, results in progressive hearing loss. Osteogenesis imperfecta (OI) is a genetic disorder characterized by recurrent fractures, blue sclera, and varying degrees of hearing impairment; and is a known risk factor for otosclerosis. After adolescence, the risk of fracture decreases, reducing the need for follow-up in OI. However, otosclerosis is a progressive disorder. In this report, we discuss two cases of familial otosclerosis with different clinical features. We hypothesize that the difference in hearing level correlates with the difference in computed tomography findings. The mother, whose case was considered severe, was prescribed hearing aids, while the daughter, who had normal hearing level, was regularly followed up.

A new phenomenon of cochlear otosclerosis: an acquired or congenital disease? - A clinical report of cochlear otosclerosis

BACKGROUND

No cochlear otosclerosis in infants with congenital bilateral SNHL has been reported.

AIMS/OBJECTIVES

We report an infant male with bilateral cochlear otosclerosis, suggesting that cochlear otosclerosis may be a congenital disease and to further analyze the etiology of and genetic expression in congenital bilateral cochlear otosclerosis. We also describe the clinical characteristics and experience of patients with bilateral cochlear otosclerosis treated with cochlear implants (CIs).

MATERIALS AND METHODS

Seven patients, including an infant, who were diagnosed with cochlear otosclerosis underwent CI surgery. Their medical records, audiological and radiological results, surgical procedures, and CI outcomes were collected and reviewed.

RESULTS

The median age at hearing loss was 38 years, ranging from 0 to 47 years. The child had bilateral hearing loss at birth and received a CI at 1 year of age. He also had growth retardation and was diagnosed with 3q+/3p- syndrome. All patients (8 ears) had better postoperative auditory performance than that preoperatively.

CONCLUSIONS AND SIGNIFICANCE

Although cochlear otosclerosis often starts at middle age and progresses slowly, it may be a congenital disease that is related to chromosome abnormality. This disease presents with SNHL or MHL, and treatment with a CI is beneficial.

Utility and value of pre-operative CT and MRI for cochlear implantation in the elderly

PURPOSE

To determine the utility and value of pre-operative imaging among the elderly population ≥70 y.o. with bilateral progressive sensorineural hearing loss undergoing cochlear implantation.

MATERIALS AND METHODS

A retrospective, cross-sectional review was performed at a tertiary referral center between 2010 and 2018 including patients ≥70 y.o. with bilateral presbycusis who underwent preoperative imaging and cochlear implantation. Primary outcome was whether pre-operative imaging changed the surgeon's surgical plan such as side of implant or abort procedure entirely. Patient characteristics including age, sex, side of implant, imaging modality, whether imaging changed surgical plan, and surgical complications were reviewed. One-way analysis of variance with post-hoc tests using the Bonferroni and Fisher's exact test were used to examine differences between groups. Secondary outcome was cost of preoperative imaging.

RESULTS

One hundred thirty-three patients (mean age 79.38 [5.51 SD]) who underwent a total of 142 surgical cases and 147 total scans. There were 92, 27, and 14 patients who underwent CT, MRI, or both, respectfully (n=133). Of the 142 implants that were placed, preoperative imaging did not reveal a contraindication to placing implant on one side over another. Total cost of imaging was $29,694. Estimated cost if 20% of cochlear implant eligible patients ≥70 y.o. underwent imaging is $7,763,490.

CONCLUSION

Decreasing unnecessary preoperative imaging can potentially decrease cost in cochlear implantation. In this sample, preoperative imaging did not affect the surgeon's choice of which side to operate on. However, imaging may provide an anatomic roadmap and contribute to either surgical confidence or caution. With the increasing amount of cochlear implant eligible elderly adults, preoperative imaging needs to be more clearly defined in this unique population.

Factors Influencing Aberrant Facial Nerve Stimulation Following Cochlear Implantation: A Systematic Review and Meta-analysis

OBJECTIVE

The purpose of this study was to systematically evaluate the literature to evaluate the rate of and associated factors with aberrant facial nerve stimulation (AFNS) following cochlear implantation. Additionally, management strategies for AFNS were assessed.

DATA SOURCES

A systematic search was performed in PubMed, Cochrane Database of Systematic Reviews, and Web of Science to identify peer reviewed research.

STUDY SELECTION

Eligible studies were those containing peer-reviewed research in English addressing AFNS following cochlear implantation. Studies with paired data were included in the meta-analysis.

DATA EXTRACTION

Three investigators independently reviewed all articles and extracted data. Bias was assessed using the National Institutes of Health Study Quality Assessment Tool.

DATA SYNTHESIS

Thirty-seven articles were included, representing 5,694 patients. The overall reported AFNS rate was 5.6% (range, 0.68-43%). Array type demonstrated a significant association with AFNS with lateral wall electrodes having a higher odds ratio than perimodiolar electrodes (odds ratio [OR] = 3.92, 95% confidence interval [CI] 1.46-10.47, p = 0.01). CI recipients with otosclerosis were also more likely to experience AFNS compared with non-otosclerosis pathology (OR = 13.73, 95% CI 3.57-52.78, p < 0.01). Patients with cochlear malformations had an overall AFNS rate of 28% (range, 5.3-43%) and those with otosclerosis had an overall rate of 26% (range, 6.25-75%). Reprogramming with or without electrode deactivation was successful for AFNS elimination. Four patients of 3,015 required explantation.

CONCLUSION

Array type and underlying cochlear pathology are associated with AFNS and implant reprogramming is an overall successful management strategy. Further research is needed to elucidate mechanism of AFNS and develop management strategies that limit impact on hearing outcomes.

Otosclerosis in an Urban Population

OBJECTIVE

To investigate the evolving prevalence of otosclerosis in a large urban population.

METHODS

A retrospective review of patients in a large, urban, public health system was conducted from January 2010 to August 2019 to identify subjects with otosclerosis. Diagnostic testing included audiometry and computed tomography scans. Sex, age at diagnosis, treatment received, race, ethnicity, and country of birth were analyzed for each subject and compared with all eligible patients in the reference population.

RESULTS

A total of 134 patients from a reference population of 672,839 were diagnosed with otosclerosis and analyzed. The otosclerosis patients were predominantly Hispanic (73%), of which the majority were foreign born (87%). The average age at onset was 46 years and 59% were women. The overall prevalence of otosclerosis was 20 of 100,000 patients. The crude prevalence of otosclerosis by ethnicity was 43 of 100,000 for Hispanics, 12.6 of 100,000 for Caucasians, and 3 of 100,000 for African Americans. Within the Hispanic population, the prevalence of otosclerosis was 60 of 100,000 for foreign-born individuals and 16 of 100,000 for those born in the USA (odds ratio [OR] = 3.69, [95% confidence interval [CI], 2.02-6.76], p < 0.0001). Prevalence was not significantly different among Caucasians and US-born Hispanics.

CONCLUSION

Otosclerosis in the studied population was most common among Hispanic patients, though it was strongly influenced by country of birth. The "imported" otosclerosis cases are best explained by environmental influence rather than ethnic susceptibility. This discrepancy is likely due to variance in measles immunization rates among North and Central American countries before 1990.

Evaluation of computed tomography parameters in patients with facial nerve stimulation post-cochlear implantation

PURPOSE

To compare the preoperative computed tomography (CT) parameters, including the thickness and density of the bone separating the upper basal turn of the cochlea (UBTC) and the labyrinthine segment of the facial nerve (LSFN), in patients with and without facial nerve stimulation (FNS) in post-cochlear implants (CI).

METHODS

A retrospective case review of 1700 CI recipients in a tertiary referral center between January 2010 and January 2020 was performed; out of the 35 recipients who were found to have FNS, 29 were included in the study. The control group comprised the same number of randomly selected patients. CT parameters of the patients were measured independently by three fellowship-trained neuro-otologists blinded to the postoperative status of the patients. Thickness in axial and coronal views and density of the bone separating the UBTC and the LSFN were measured.

RESULT

There was satisfactory agreement between the readings of the three reviewers. The distances (in mm) between the UBTC and LSFN obtained from the coronal (0.43 ± 0.24 vs. 0.63 ± 0.2) and axial (0.42 ± 0.25 vs. 0.6 ± 0.18) views were statistically lower in the FNS group (p = 0.001 and 0.005, respectively). The density (in HU) of the bony partition was also statistically lower in the FNS group (1038 ± 821 vs. 1409 ± 519; p = 0.029).

CONCLUSION

Patients who experienced FNS postoperatively had significantly lower distance and bone density between the UBTC and the LSFN. This finding can help surgeons in preoperative planning in an attempt to decrease the occurrence of FNS.

Investigating Facial Nerve Stimulation After Cochlear Implantation in Adult and Pediatric Recipients

OBJECTIVES/HYPOTHESIS

Facial nerve stimulation (FNS) can occur after cochlear implantation for a small number of recipients. This study aimed to investigate if a correlation exists between the variables involved in FNS.

STUDY DESIGN

Retrospective cohort review.

METHODS

There were 32 out of 1,100 cochlear implant recipients who experienced FNS in our clinic between 2010 and 2019. The following variables were recorded from a retrospective chart review: grade of FNS, onset of FNS, the number of channels stimulating FNS, and radiological findings of abnormalities in the inner ear. Statistical analyses were performed to identify a correlation between any of the variables involved. The techniques used to reduce FNS were analyzed.

RESULTS

Eleven adult ears had progressive hearing loss, three had idiopathic sudden sensorineural hearing loss (SNHL), and one congenital SNHL. All pediatric ears were diagnosed with congenital SNHL, except for one ear with idiopathic sudden SNHL. The grade of FNS ranged from mild stimulation or slight motion in the eye, mouth, nasolabial, or forehead regions (n = 8) to total severe stimulation of the facial musculature and/or severe pain (n = 3). The onset of FNS occurred immediately after activation for nine ears, and up to 16 months later for the other subjects. A significant correlation was observed between the number of channels stimulating FNS, the grade of FNS, and the radiological findings of the inner ear. FNS was completely resolved for 30 ears and partially resolved for two ears.

CONCLUSIONS

FNS can occur any time after cochlear implantation and can affect both adult and pediatric. However, it can be effectively resolved using specific fitting techniques.

LEVEL OF EVIDENCE

2c Laryngoscope, 131:374-379, 2021.

Double Ring in Cochlear Otosclerosis: A Limit to Cochlear Implantation? The Solution Is the Surgical Approach

We present a case of a 50-year patient with a severe form of otosclerosis (double ring) that was successfully implanted. We used a bone-anchored hearing implant for restoring the hearing in the right side and a cochlear implant in the left side; both surgeries did not show any complications. For reducing the risk of a secondary bone ossification related to the trauma of cochleostomy for electrode's insertion, we used a round window approach. The patient recovered a normal auditory threshold and normal speech perception capacity both in silence and noise conditions 1 year after surgery.

Carhart Notch-A Prognostic Factor in Surgery for Otosclerosis

OBJECTIVE

Otosclerosis is an underlying disease of the bony labyrinth. This disorder, occurring only within the area of a person's temporal bone, is characterized by a progressive hearing loss and tinnitus.

MATERIAL AND METHODS

The study looked for the answer to the question of whether the presence or absence of Carhart notch in the presurgical tonal audiogram affects the final outcome of the otosclerosis surgery.

RESULTS

The analysis included 140 patients operated on for the first time due to otosclerosis between 2010 and 2016. The study group consisted of 107 women aged from 19 to 62 (average age: 40.33) and 33 men aged 27 to 59 (average age: 38.23). Analysis showed a statistically better result of stapedotomy in patients without the notch than in the same procedure in patients with the notch present. The opposite situation occurred in the case of stapedectomy.

CONCLUSION

(1) The presence of a refraction of the bone conduction curve with a depth of 10 to 20 dB at a frequency of 2000 Hz (the so-called Carhart notch) in the presurgical tonal audiogram is an unfavorable prognostic factor in relation to closing the cochlear reserve and improving bone conduction after the stapedotomy. (2) Regardless of the presence or absence of Carhart notch in the presurgical tonal audiogram, stapedotomy is the procedure with the highest efficiency in the treatment of otosclerosis.

"Third Window" and "Single Window" Effects Impede Surgical Success: Analysis of Retrofenestral Otosclerosis Involving the Internal Auditory Canal or Round Window

Background and Objectives: We aimed to identify prognostic computed tomography (CT) findings in retrofenestral otosclerosis, with particular attention paid to the role of otosclerotic lesion area in predicting post-stapedotomy outcome. Materials and Methods: We included 17 subjects (23 ears) with retrofenestral otosclerosis who underwent stapedotomy. On preoperative CT, the presence of cavitating lesion and involvement of various subsites (cochlea, round window [RW], vestibule, and semicircular canal) were assessed. Pre- and post-stapedotomy audiometric results were compared according to the CT findings. The surgical outcomes were analyzed using logistic regression with Firth correction. Results: Cavitating lesions were present in 15 of 23 ears (65.2%). Involvement of the RW was the strongest predictor of unsuccessful surgical outcome, followed by involvement of the internal auditory canal (IAC) and the cochlea. Conclusions: RW and IAC involvement in retrofenestral otosclerosis were shown to predict unsuccessful outcomes. While a “third window” effect caused by extension of a cavitating lesion into the IAC may dissipate sound energy and thus serve as a barrier to desirable postoperative audiological outcome, a “single window” effect due to an extension of retrofenestral otosclerosis into the RW may preclude a good surgical outcome, even after successful stapedotomy, due to less compressible cochlear fluid and thus decreased linear movement of the piston.

A Biochemical Analysis of the Stapes

BACKGROUND Otosclerosis is a primary disease of the bony labyrinth. In the course of otosclerosis, abnormal resorption and recalcification of the endochondral layer of the temporal bone is observed. The otosclerotic process most commonly develops in the anterior part of the oval window. MATERIAL AND METHODS We analyzed stapes superstructures from 4 patients undergoing surgery for otosclerosis. The first step involved tissue assessment under a scanning electron microscope. The resulting images were analyzed in terms of morphological changes. The stapes superstructure was then divided into small "ossicles", including fragments from the closest vicinity of the stapes footplate and a fragment of the head of the stapes. This material was examined using a scanning electron microscope with a unit for chemical analysis in microareas. RESULTS Chemical analysis confirms the appearance of considerable quantities of the following elements: carbon, oxygen, potassium, and calcium, and the appearance of small quantities of sodium and magnesium. Based on a detailed analysis of the chemical composition, these fragments could represent a calcium phosphate compound from the following system: CaO-P₂O₅-H₂O. Fragments of the superstructure from the region closest to the base of the stapes demonstrated a considerably larger presence of carbon, oxygen, and nitrogen, which most likely suggests an increased metabolic process in this region. CONCLUSIONS Our analysis revealed an increased metabolic activity in the closest vicinity of the otosclerotic focus, the fissula ante fenestram. The increased metabolism correlated with the bone tissue changes seen on scanning electron microscopy.

Which imaging modality in cochlear implant candidates?

PURPOSE

There is no guideline or consensus on preoperative radiologic imaging modality despite the fact that it has a vital importance in appropriate candidacy selection of cochlear implantation. We aimed to find out the role of high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) on surgical planning, intraoperative technique in cochlear implant candidates.

METHODS

The clinical charts, imagings, and operative reports of patients who underwent cochlear implant surgery at a tertiary institution were retrospectively examined.

RESULTS

611 patients (503 children and 108 adult) were enrolled into the study. We found 11 different pathologies in MRI which could not be seen in HRCT. However, we decided the side of surgery according to MRI in only three of them in which the pathology was cochlear nerve hypoplasia. Two patients with cochlear nerve hypoplasia were children with prelingual deafness and one was adult with perilingual deafness. Moreover, we changed the surgical planning of side according to both imaging modalities in nine patients. Seven of them were children and two were adult. One of these adults had cochlear anomaly, and another had bilateral temporal bone fracture.

CONCLUSIONS

We suggest both imaging modalities in pediatric candidates. However, in adults, we think that superiority of either imaging modalities is still contradictive. We had only three adult patients and the decision of the side of surgery was made according to MRI in one of them and to both imaging modalities in the other two adults.

Cochlear Implant Users with Otosclerosis: Are Hearing and Quality of Life Outcomes Worse than in Cochlear Implant Users without Otosclerosis?

Background: The otosclerotic process may influence the performance of the cochlear implant (CI). Difficulty in inserting the electrode array due to potential ossification of the cochlea, facial nerve stimulation, and instability of the results are potential challenges for the CI team. Objectives: To evaluate hearing results and subjective outcomes of CI users with otosclerosis and to compare them with those of CI users without otosclerosis. Method: Retrospective review of 239 adults with bilateral profound postlingual deafness who underwent unilateral cochlear implantation between 1992 and 2017. Hearing and speech understanding were assessed via pure-tone audiometry and speech perception tests. Subjective outcomes were assessed via the Nijmegen Cochlear Implant Questionnaire (NCIQ), the Glasgow Benefit Inventory (GBI), and the Hearing Implant Sound Quality Index (HISQUI19) at 6 months, 12 months, and at the last follow-up. Results: Subjects were 22 CI users with otosclerosis and 217 without otosclerosis. Both groups had a similar duration of deafness and age at CI implantation. Results did not significantly differ according to group: no significant intergroup difference was found regarding the frequency of complete electrode insertion, facial stimulation, reimplantation, or PTA4 scores at the last follow-up. Regarding speech perception, no significant intergroup difference was found on any test or at any interval. Further, subjective outcomes, as measured by the GBI, NCIQ, and HISQUI19, did not significantly differ between groups. Conclusions: Adults with otosclerosis and profound hearing loss derive significant benefit from CI use. Audiological and self-reported outcomes are not significantly different from that of other CI users with postlingual deafness.

Otosclerosis: An update on diagnosis and treatment

Otosclerosis is a complex and progressive disease of pathological bone remodeling that affects the otic capsule of the temporal bone, resulting in hearing loss. Although traditional diagnostic methods are still used, improvements in technology and research have paved the way for additional diagnostic techniques and advancements. The traditional treatment of otosclerosis, stapes surgery, is now being augmented or replaced by innovations in hearing aid technology and cochlear implants. Earlier diagnosis of otosclerosis can occur through understanding of the cause, risk factors, and current diagnostic testing.

An alternative approach to mixed hearing loss in otosclerosis: stapes surgery combined with an active middle-ear implant

OBJECTIVE

To report a novel management strategy for mixed hearing loss in advanced otosclerosis.

METHODS

A 50-year-old male was referred to St Thomas' Hearing Implant Centre with otosclerosis; he was no longer able to wear conventional hearing aids because of recurrent otitis externa. The patient underwent short process incus vibroplasty (using the Med-El Vibrant Soundbridge device), followed at a suitable interval (six weeks) by stapes surgery. The main outcome measures were: pure tone audiometry, functional gain and monosyllabic word recognition scores.

RESULTS

Post-operative pure tone audiometry showed a reduction of the mean air-bone gap from 55 dB HL to 20 dB HL. The residual mixed hearing loss was rehabilitated with the Vibrant Soundbridge, with an average device gain of 32 dB. The monosyllabic word recognition scores in quiet at 65 dB improved from 37 to 100 per cent when using the Vibrant Soundbridge at six months after switch-on of the device.

CONCLUSION

Stapedotomy in conjunction with incus short process vibroplasty (i.e. inner-ear vibroplasty) is a safe and promising procedure for managing advanced otosclerosis with mixed hearing loss in selected patients.

Can Preoperative CT Scans Be Used to Predict Facial Nerve Stimulation Following CI?

OBJECTIVES

1) To determine the ability of preoperative computed tomography (CT) to predict facial nerve stimulation (FNS) after cochlear implantation (CI). 2) To recognize the limitations of CT in predicting FNS.

STUDY DESIGN

Patient control study.

SETTING

Tertiary care academic medical center.

SUBJECTS

Adult patients with CI from 2003 to 2015.

METHODS

Patients with severe FNS (n = 4) were compared with randomly selected CI patients (n = 28). Three blinded reviewers evaluated preoperative temporal bone CT scans to measure the distance from the labyrinthine segment of the facial nerve to the basal turn of the cochlea and attempted to predict whether or not the subject had FNS after CI.

RESULTS

In total, 32 CT scans were evaluated representing 49 ears that underwent CI.The distances (mm) measured from the labyrinthine segment of the facial nerve to the basal turn of the cochlea in both the axial (0.3 ± 0.3 versus 0.6 ± 0.3) and coronal (0.4 ± 0.2 versus 0.6 ± 0.2) orientation were significantly different between the two groups (p = 0.0001 and p = 0.0034) respectively. The intraclass correlation coefficient demonstrated good (K > 0.7) reviewer correlation in both the reviewers' measurements and predictions. The sensitivity, specificity, positive predictive value, and negative predictive value for preoperative CT scans to predict FNS were 38.5, 85.1, 19.2, and 93.8% respectively. The reviewers were 23% accurate in predicting FNS.

CONCLUSION

Based on a blinded retrospective patient-control study, CT scan measurements show a significantly reduced distance between the labyrinthine facial nerve and the basal turn of the cochlea in patients with FNS. However, it is difficult to predict who will have FNS based on these measurements.

Third-generation bisphosphonates for cochlear otosclerosis stabilizes sensorineural hearing loss in long-term follow-up

Objective

To assess long‐term hearing outcomes in patients treated with third‐generation bisphosphonates for otosclerosis‐related progressive sensorineural hearing loss (SNHL).

Study Design

Retrospective case series review

Methods

We performed a retrospective case series review of patients with otosclerosis and progressive SNHL. Patients were treated with either risedronate or zoledronate after a diagnosis of otosclerosis with a significant SNHL component. Bone conduction pure tone threshold averages (BC‐PTAs) and word recognition scores (WRS) before and after bisphosphonate administration in long‐term follow‐up was analyzed. Significant change in BC‐PTA was defined as greater than 10dB or between 4% and 18% in WRS based on binomial variance.

Results

Seven patients were identified and 14 ears met inclusion criteria. Three patients were female and the mean age was 48.3 ± 10.3 years. The mean duration between treatment with bisphosphonate administration and long‐term post‐treatment follow‐up audiometry was 87.6 ± 18.3 months, with a range of 61.6 to 109.1 months and median of 89.2 months. Analysis using BC‐PTA and WRS demonstrated that 11 ears remained stable while 2 improved and 1 worsened. No patient experienced any major complication as the result of bisphosphonate therapy.

Conclusion

Treatment with third‐generation bisphosphonates is associated with stability in otosclerosis‐related sensorineural hearing over 5‐ to 9‐year period. These results suggest that such medications may prevent the progression of SNHL in patients with otosclerosis.

Level of Evidence

4 (Case series).

Outcomes of cochlear reimplantation in adults

OBJECTIVE

To determine the indications for, and auditory outcomes following, cochlear reimplantation in adults and investigate factors influencing outcome.

STUDY DESIGN

Retrospective case series.

SETTING

Cochlear implant program in a tertiary care hospital.

PATIENTS

Thirty adults (32 ears) who have undergone cochlear reimplantation in the ipsilateral ear.

INTERVENTION(S)

Explantation and reimplantation of cochlear implant.

MAIN OUTCOME MEASURE(S)

Speech discrimination as measured using Bamford-Kowal Bench sentence testing in quiet (BKBq) and noisy (BKBn) environments.

RESULTS

Best BKBq improved from 58.5% to 71.4% (p = 0.0242), and BKBn improved from 60.9% to 67.2% (p = 0.826) after reimplantation. Device failure was the most common indication for reimplantation. There was no significant difference in failure rate or outcome between implant manufacturers. The mean time to reimplantation was 4.7 years, and this was not related to auditory outcome. Otosclerosis and Ménière's disease may predispose to a worse auditory outcome after reimplantation.

CONCLUSION

Cochlear reimplantation does not have a detrimental effect on auditory outcomes and in some cases results in improved speech perception.

Role of HRCT and MRI of the Temporal Bone in Predicting and Grading the Degree of Difficulty of Cochlear Implant Surgery

This study proposes a grading system based on a 10-point scoring chart of high resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) imaging findings in patients being assessed preoperatively for cochlear implantation. This system helps in objectively assessing the degree of difficulty of the surgical procedure and alerts the surgeons to any potential intraoperative complications. This is a prospective study carried out at a tertiary referral center where 55 patients with bilateral profound sensorineural hearing loss were evaluated by HRCT and MRI and subsequently underwent cochlear implantation. HRCT examinations were performed on a 64 slice multidetector CT scanner. MRI examinations were performed on a 3.0 Tesla MRI scanner. A 10-point scoring chart was devised based on specific imaging findings and all patients were assigned potential difficulty scores (PDS) based on HRCT and MRI findings. Surgical times were documented in each case and each imaging point on the scoring chart was correlated with the surgical times. Eight out of theó ten points in the scoring chart proved to be statistically significant in predicting the degree of difficulty of the surgical procedure. After grading the pre-operative imaging examinations based on the 10-point scoring chart we concluded that patients who have PDS between 0 and 3 (Grade 1) have uneventful and uncomplicated surgery with the lowest intraoperative times. Patients with PDS between 4 and 7 alert the surgeon to moderate surgical difficulty and longer intraoperative times. PDS of 8 and above indicate prolonged and difficult surgery.

Cochlear implantation outcomes in advanced otosclerosis

INTRODUCTION

Several studies support the use of cochlear implants (CI) in far-advanced otosclerosis (FAO).

MATERIAL AND METHODS

We compared our results of CI in patients with FAO and unknown origin hearing loss (UOHL) and our incidence of facial electrical stimulation and difficult insertion of the electrode bundle up to 3 to 5 years from surgery.

RESULTS

We found 17 patients with CI in FAO and UOHL. FAO patients achieved better results on the pure tone average (PTA) and recognition of monosyllables by GEE test (p=0.022; p=0.006), and particularly at 1 year on the PTA (p=0.002), at 6 months and a year in monosyllables (p=0.002; p=0.001), and at 6 months in disyllables (p=0.004). There were no differences toward complications.

CONCLUSION

In our experience, placement of CI in FAO has proven successful, with results comparable to other similar cohorts, and with low complications.

Adult progressive sensorineural hearing loss: is preoperative imaging necessary before cochlear implantation?

OBJECTIVE

Preoperative evaluation of cochlear implant candidate includes routine imaging to identify anatomic abnormalities that may preclude or complicate implantation, such as cochlear aplasia, absent/narrowed internal auditory canals, cochlear ossificans, or significant traumatic fracture. The aim of this study is to determine if preoperative imaging is necessary in select cochlear implant candidates, thus defraying cost and ionizing radiation.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary referral facility.

PATIENTS

Adult patients with progressive sensorineural hearing loss without evidence of head trauma, meningitis, or congenital hearing loss who underwent cochlear implantation.

INTERVENTIONS

Diagnostic and therapeutic.

MAIN OUTCOME MEASURES

Preoperative radiologic abnormalities, deviation from standard cochlear implant operation.

RESULTS

One hundred eighteen cochlear implants met inclusion criteria; 23.7% of CT scans had a documented abnormality, including chronic otitis media (14.4%), otosclerosis (4.2%), and an enlarged vestibular aqueduct (3.4%). There were 6 eventful surgeries in patients with normal documented CT scan. Events included multiple insertion attempts (3.4%), CSF leak (2.5%), and no apparent round window (2.5%). In every case, a cochlear implant was able to be placed successfully.

CONCLUSION

In the appropriately selected patient, preoperative imaging is not necessary as it does not impact the cochlear implant surgery and will defray cost and ionizing radiation.

Cochlear implantation outcomes in patients with far advanced otosclerosis

OBJECTIVES

To compare hearing outcomes in patients with far advanced otosclerosis (FAO) undergoing cochlear implantation to an age-matched group of controls, to describe the effects of cochlear ossification on hearing, and to review the adverse effects of implantation in patients with FAO.

HYPOTHESIS

Hearing performance in patients with FAO after cochlear implantation is comparable to similarly treated postlingually deafened adults without FAO. Ossification or retrofenestral otosclerosis does not predict poor hearing outcomes. Modiolar-hugging technology reduces postoperative facial nerve stimulation.

STUDY DESIGN

Retrospective chart review.

SETTING

Academic neurotologic tertiary referral center.

PATIENTS

Thirty patients with FAO, who metaudiological criteria for cochlear implantation, were compared to 30 age-matched controls, postlingually deafened by non-otosclerotic causes.

MAIN OUTCOME MEASURES

Audiometric pre- and postoperative speech reception threshold, word, and sentence scores were analyzed. The presence of retrofenestral findings on computed tomography or intraoperative cochlear ossification were noted.

RESULTS

In the FAO group, radiographic abnormalities were noted in 26.4% of patients. Intraoperative ossification requiring drillout was seen in 29.4% of patients. None developed postoperative facial nerve stimulation. There was no difference between the FAO and control groups in the mean short-term and long-term postoperative speech reception threshold, word, and sentence scores (P = .77). The presence of radiographic abnormalities did not predict hearing outcome. Intraoperative cochlear ossification was not associated with worse short-term word and sentence scores (P = .58 and 0.79, respectively), and for the long-term hearing outcome (P = .24).

CONCLUSIONS

In patients with FAO, effective and safe hearing rehabilitation can be accomplished with cochlear implantation.

Cochlear otosclerosis

PURPOSE OF REVIEW

The aim of this study is to summarize current advances in research and clinical aspects of cochlear otosclerosis.

RECENT FINDINGS

Recent studies have revealed that otosclerosis is a process of bone remodeling that is unique to the otic capsule only. Even though no obvious bone remodeling is seen in the otic capsule under normal conditions, remodeling starts when some molecular factors trigger the capsule in certain patients who have genetic and/or environmental tendencies.

SUMMARY

Cochlear otosclerosis is defined as otosclerosis located in the otic capsule involving the cochlear endosteum and causing sensorineural hearing loss or mixed-type hearing loss. It has been clearly shown that, when otosclerosis is sufficiently severe to involve the cochlear endosteum, it usually fixes the stapes as well.

Stimulation of the facial nerve by intracochlear electrodes in otosclerosis: a computer modeling study

HYPOTHESIS

The increased likelihood of facial nerve stimulation (FNS) with cochlear implantation in advanced cochlear otosclerosis is due to a lowering of the facial nerve excitation threshold with increasing bone demineralization.

BACKGROUND

Facial nerve stimulation can complicate cochlear implant fitting, often necessitating the deactivation of certain electrode contacts.

METHODS

High-resolution computed tomographic scans were used to estimate anatomic features of the cochlea and the facial nerve canal. These features were added to a detailed computational model of the implanted human cochlea to examine the consequences of increased conductivity of the bone of the otic capsule. The model took into account the electrode contact type (banded or otherwise) and position (perimodiolar or lateral wall) of the electrode array.

RESULTS

Contrary to the hypothesis, facial nerve thresholds were found to be slightly elevated with increased conductivity of the surrounding bone. However, the threshold and most comfortable loudness levels of the auditory nerve increase more rapidly owing to the reduced current density in the scala tympani as current leaks more easily out of the cochlea. Lateral wall electrodes were predicted to result in an increased likelihood of FNS. A progressively reduced probability of FNS was indicated for the full-band, half-band, and plated electrode arrays, respectively.

CONCLUSION

The clinical observation of increased FNS in cases of cochlear otosclerosis has been demonstrated in a computational model. Rather than decreased FN threshold, it is the increased levels for cochlear stimulation that is the main factor. Particularly, perimodiolar designs with more shielding against lateral spread of current could reduce the likelihood of FNS.

[Controversial points in cochlear implantation for patients with cochlear otosclerosis]

Most cases of otosclerosis show pathological changes only around the oval window. On the other hand, it is known that cavernous changes extending to the cochlea induce progressive sensorineural deafness. Three patients with severe bilateral deafness and severe cochlear otosclerosis as diagnosed by CT underwent cochlear implantation. The postoperative hearing abilities were satisfactory in two of the three patients at one year after the operation. However, one patient with advanced otosclerosis suffered from the complication of facial nerve stimulation two months later after the cochlear implantation. His available cochlear implant electrodes gradually decreased due to the facial nerve stimulation and at last the cochlear implant was no longer beneficial for reacquisition of his hearing ability. His CT densitometry revealed marked degradation of the CT value in the cochlear basal turn circumference in comparison with that in other patients showing good courses after the cochlear implantation. In conclusion, a cochlear implant operation is valuable in patients with severe sensorineural deafness with cochlear otosclerosis. However, we should cautious in performing cochlear implantation in patients with severe demineralization of the cochlear optic capsule.

Otosclerosis: mid-term results of cochlear implantation

INTRODUCTION

Constant histological changes in otosclerosis lead to progressive hearing loss which may end up in a profound hearing loss and then be treated by means of cochlear implants. These progressive changes could be followed by changes in cochlear implants fitting and speech discrimination results over the years.

OBJECTIVES

The aim of the study is to correlate the progressive histological changes to the cochlear implant clinical outcomes (fitting and speech discrimination results). Also main complications (facial nerve stimulation and difficulties at insertion) and new complications will be discussed.

DESIGN

A 5-year prospective case-control study was performed in order to compare cochlear implant results in otosclerosis patients to those in a matched-pair control group.

MATERIALS AND METHODS

Fifteen otosclerosis patients were followed throughout the study. Preoperatively temporal bone high-resolution computed tomography, electrically evoked auditory brainstem responses and speech discrimination tests were performed in order to select the patients to be implanted.

RESULTS

Not only difficulties with electrode guide insertion were reported, but also difficulties with fitting over the years, due to increasing difficulties to spread the electrical stimuli, which provokes increasing thresholds, maximum comfort levels and charges needed to stimulate hearing cells in basal and medial turn electrodes (p < 0.05), which required deactivating some basal and medial turn electrodes in order to improve cochlear implant effectiveness. The results demonstrated no statistical differences in speech discrimination in otosclerosis patients compared to the control group (p > 0.05). Several complications were reported: facial nerve stimulation (7.14%) and sudden episodes of tinnitus and headaches (14.28%).

CONCLUSIONS

Although progressive histological changes in otosclerosis lead to increasing thresholds, maximum comfort levels and charges needed to stimulate hearing cells, speech discrimination results support the cochlear implantation in otosclerosis.

Preoperative integrated imaging in paediatric cochlear implantation

Sensorineural hearing loss affects one to two children out of 1000 born apparently healthy and 9% approximately of those born with the risk of different pathologies. The origin of premature deafness is unknown in 25% of children whereas it is genetic in some cases. Prevention and early diagnosis, possibly within six to eight months, aim to avoid deafness becoming a cause of disability. The aim of the present study was to establish the optimal preoperative assessment with a diagnostic imaging protocol involving the integrated use of CT and MRI in the selection of the candidates for cochlear implantation. Twenty children were assessed, divided into three different groups: A) those who had CT only; B) those who had only MR; C) those who had both CT and MRI. The purpose was to estimate diagnostic accuracy in preoperative planning and the role of imaging in the diagnostic protocol for children's deafness. The petrous pyramid was studied with a CT Picker PQ 6000 system to high resolution in the axial and coronal planes, and with an MR Intera Philips 0.5 T device by means of acquisition of sequences B-TFE T2 3D and MIP reconstructions on radial coronal plans. This study was completed successfully for morphological brain MRI examination to complete the diagnosis. The following abnormalities were found in six patients (30%): one case of incomplete partition (Mondini malformation); two cases of vestibular aqueduct enlargement; two cases with anomalous jugular bulb positioning; one case with cochlear ossification. In the remaining 70%: eight patients had no anatomical anomalies; CT and MRI imaging were normal in six patients with minor abnormalities disclosed at surgery (one case of the stapedial artery emerging from the promontory); three anatomical variants of the round window, and two abnormal course of the facial nerve). We emphasize the importance of integrated CT and MRI imaging in the study of children with sensorineural hearing loss. The combination of CT and MRI has been shown to be superior to either modality used alone in view of "risk-free" cochear implantation. High resolution computed tomography and magnetic resonance images obtained by B-TFE T2-weighted 3D sequences help the surgeon in planning the operation and predict operative difficulty and potential complications in paediatric cochlear implant candidates.