Development of Automated Tool for Electrode Array Insertion and its Study on Intracochlear Pressure

Cochlear implantation is the most successful approach for people with profound sensorineural hearing loss. Manual insertion of the electrode array may result in damaging the soft tissue structures and basilar membrane. An automated electrode array insertion device is reported to be less traumatic in cochlear implant surgery.

OBJECTIVES

The present work develops a simple, reliable, and compact device for automatically inserting the electrode array during cochlear implantation and test the device to observe intracochlear pressure during simulated electrode insertion.

METHODS

The device actuates the electrode array by a roller mechanism. For testing the automated device, a straight cochlea having the dimension of the scala tympani and a model electrode is developed using a 3D printer. A pressure sensor is utilized to observe the pressure change at different insertional conditions.

RESULTS

The electrode is inserted into a prototype cochlea at different speeds without any pause, and it is noticed that the pressure is increased with the depth of insertion of the electrode irrespective of the speed of electrode insertion. The rate of pressure change is observed to be increased exponentially with the speed of insertion.

CONCLUSION

At an insertion speed of 0.15 mm/s, the peak pressure is observed to be 133 Pa, which can be further evaluated in anatomical models for clinical scenarios.

LEVEL OF EVIDENCE

N/A Laryngoscope, 134:1388-1395, 2024.

Effectiveness and Safety of Prochlorperazine in Indian Patients with Acute Vertigo: Results from a Large, Prospective, Post-marketing Observational Study

Aim

To assess the efficacy and safety of prochlorperazine in Indian patients with acute vertigo.

Methods

In this prospective, multicenter, open-label, post-marketing observational study, patients with acute peripheral vertigo of different etiologies received 5 mg prochlorperazine thrice a day for 5 days. The primary endpoints were percentage of patients with improvement in (1) vertigo symptoms and (2) clinical response as per scale for vestibular vertigo severity level and clinical response evaluation (SVVSLCRE) from baseline to end of treatment (Day 6). The key secondary endpoints were (1) improvement in nystagmus grading, and (2) safety and tolerability Efficacy of prochlorperazine by route of administration of first prochlorperazine dose (oral or intramuscular) was also assessed.

Results

Of 1716 enrolled patients (mean [standard deviation, SD]) age (42.0 [12.95] years; 53.6% men), 57.4% were diagnosed with Meniere's disease, followed by vestibular neuritis (17.4%), labyrinthitis (16.7%), or ear surgery (8.5%). In the overall population, 91.1% of patients showed improvement in clinical response per SVVSLCRE grading at Day 6 (p < 0.0001 vs. non-responders). Nystagmus grading was improved in 99.7% (of patients. No adverse drug reactions events were reported. Tolerability of prochlorperazine was rated as good, very good, and excellent by 43.6%, 32.9% and 20.7% of patients, respectively. Among patients with postoperative vertigo, 80.1% showed improvement in clinical response. In the intramuscular and oral subsets, 85.5% and 92.1% of patients showed improved clinical response, respectively.

Conclusion

Prochlorperazine showed improvement in severity of symptoms and clinical response in all subsets of vertigo patients, with a good safety and tolerability profile.

Trial Registration Number

CTRI/2022/01/039287.

Date of Registration

10 January 2022.

Complication profile in a cochlear implantation- surgical audit in a large study population of low socio-economic status in a developing country

OBJECTIVES

To audit surgical complications and their management in cochlear implant (CI) recipients in a tertiary care referral otorhinolaryngology center in South India.

MATERIALS AND METHODS

Hospital data on 1,250 CI surgeries performed from June 2013 to December 2020 was reviewed. This is an analytical study with data collected from medical records. The demographic details, complications, management protocols and relevant literature were reviewed. Patients were divided into the following five age groups: 0-3 years, 3-6 years, 6-13 years, 13-18 years and above 18 years. Complications were divided into major and minor and complication occurrence was divided into peri-operative, early post-operative, and late post-operative, and the results were analyzed.

RESULTS

The overall major complication rate was 9.04% (including 6.0% due to device failure). If the device failure rate was excluded, the major complication rate was 3.04%. The minor complication rate was 6%.

DISCUSSION

CI is the gold standard in the management of patients with severe to profound hearing loss with minimal benefit from conventional hearing aids. Experienced tertiary care CI referral and teaching centers manage complicated implantation cases. Such centers typically audit their surgical complications, providing important reference data for young implant surgeons and newer centers.

CONCLUSION

Although not bereft of complications, the list of complications and its prevalence is sufficiently low to warrant the advocacy of CI worldwide, including developing countries with low socio-economic status.

Noise Pollution and Associated Hearing Loss in a Metropolitan City-a Preliminary Report

To measure the amount of noise produced in busy parts of a metropolitan and also to assess the audiological status of the civilians exposed to such noise. Cross-sectional study for one year between June 2017 and May 2018 was conducted. Noise was measured in four busy parts of an urban city with a digital sound level meter. People involved in various occupations in the busy parts for more than one year within the age range of 15-45 years were included. Maximum noise level recorded was 106.4 dBA in Koyembedu. Average noise was around 70-85 dBA in Chennai. Totally 100 people were subjected to audiological assessment (69 Males; 31 Females). Among them 93% had hearing loss. Hearing loss was almost equal both in sexes. Sensory hearing loss was the major type (83%). All areas were almost equally affected with maximum (100%) being affected in Annanagar and Koyembedu. The right ear was more affected than the left. All age groups were affected among which the working age group (36-45) years was most affected. The unskilled occupation group was most affected (100%). There was a positive relation between noise levels and hearing loss. Duration of exposure did not have positive correlation with hearing loss. Noise pollution and its induced hearing loss was more prevalent and increased in all four areas. As hearing loss due to noise pollution is predominant as observed in the study, awareness about noise pollution and its effects among the community is a necessity.

A Case of Langerhan's Cell Histiocytosis of Temporal Bone

We present a case of isolated Langerhans' cell histiocytosis in a six year old child who presented with right otorrhoea, retro-aural swelling and hearing loss. The preoperative provisional diagnosis was cholesteatoma, per operative differential diagnosis was rhabdomyosarcoma and final histological and immunohistochemistry diagnosis was Langerhans' cell histiocytosis.

Worldwide Variation in Cochlear Implant Candidacy

BACKGROUND

The aim of this study was to find out how candidacy criteria have evolved differently across the globe.

METHODS

Candidacy criteria and outcome measurements applied in 19 HEARRING clinics were analyzed.

RESULTS

Candidacy criteria vary between clinics. Overall, both bilateral implantation and cochlear implantation in patients with single-sided deafness are becoming more frequent.

CONCLUSION

Standardized outcome measurement instruments need to be applied to provide access to the hearing world to all patients with hearing loss who would benefit from cochlear implantation.

Suitable Electrode Choice for Robotic-Assisted Cochlear Implant Surgery: A Systematic Literature Review of Manual Electrode Insertion Adverse Events

Background and Objective

The cochlear implant (CI) electrode insertion process is a key step in CI surgery. One of the aims of advances in robotic-assisted CI surgery (RACIS) is to realize better cochlear structure preservation and to precisely control insertion. The aim of this literature review is to gain insight into electrode selection for RACIS by acquiring a thorough knowledge of electrode insertion and related complications from classic CI surgery involving a manual electrode insertion process.

Methods

A systematic electronic search of the literature was carried out using PubMed, Scopus, Cochrane, and Web of Science to find relevant literature on electrode tip fold over (ETFO), electrode scalar deviation (ESD), and electrode migration (EM) from both pre-shaped and straight electrode types.

Results

A total of 82 studies that include 8,603 ears implanted with a CI, i.e., pre-shaped (4,869) and straight electrodes (3,734), were evaluated. The rate of ETFO (25 studies, 2,335 ears), ESD (39 studies, 3,073 ears), and EM (18 studies, 3,195 ears) was determined. An incidence rate (±95% CI) of 5.38% (4.4–6.6%) of ETFO, 28.6% (26.6–30.6%) of ESD, and 0.53% (0.2–1.1%) of EM is associated with pre-shaped electrodes, whereas with straight electrodes it was 0.51% (0.1–1.3%), 11% (9.2–13.0%), and 3.2% (2.5–3.95%), respectively. The differences between the pre-shaped and straight electrode types are highly significant (p < 0.001). Laboratory experiments show evidence that robotic insertions of electrodes are less traumatic than manual insertions. The influence of round window (RW) vs. cochleostomy (Coch) was not assessed.

Conclusion

Considering the current electrode designs available and the reported incidence of insertion complications, the use of straight electrodes in RACIS and conventional CI surgery (and manual insertion) appears to be less traumatic to intracochlear structures compared with pre-shaped electrodes. However, EM of straight electrodes should be anticipated. RACIS has the potential to reduce these complications.

Socio-demographic profile and its influences on rehabilitation in children undergoing revision cochlear implantation - MERF experience

INTRODUCTION

Revision cochlear implant surgery (RIS) is an unusual and unfortunate event, but not an uncommon occurrence in today's time, with more and more children being implanted. It is accepted that a pediatric cochlear implant recipient may require one or two revision procedures during their lifetime. The indication of RIS can be due to a multitude of causes like trauma, device failure (hard failure or soft failure), infection at the implant site, electrode extrusion, device migration, magnet migration, and upgradation in the technology. Scenarios, where the child is deprived of hearing once again is worrisome for the family. And, they need financial and psychological assistance as well.

AIMS AND OBJECTIVES

(1) To scrutinize the socio-demographic profile of children who underwent RIS. (2)To profile the social, intellectual, and economic backgrounds of these families.

MATERIAL AND METHODS

A retrospective, observational, non-interventional, cohort study conducted at the Implantation otology department of Madras ENT Research Foundation (MERF), Chennai, Tamil Nadu, India.

DATA COLLECTION

(1) Detailed medical records of all the children who satisfied the inclusion criteria were reviewed.(2)This was followed up by a telephonic interview with the guardian of the consenting patients, to obtain further data based on a customized questionnaire.

SAMPLE SIZE

Of the 99 children who underwent RIS, 80 families consented to be part of the study.

STATISTICAL ANALYSIS

(1) Cause of revision implant surgery and Family system Risk estimate.(2) Correlation of sex, family system, patient non-compliance to habilitation, and residential area with RIS.(3) Correlation of the residential area of the patient with completion of 1-year habilitation.

RESULTS

A significant association observed between RIS and Sex (P = 0.03). A significant co-relation between patient non-compliance to habilitation and cause of revision implant surgery observed (P = 0.02). A significant co-relation was seen between residential area (Rural/Urban) and cause of RIS (P = 0.02). A statistically significant correlation seen with the residential area (Rural/Urban) of the child and completion of 1-year habilitation (P = 0.01). Uni-variant association was found between patients that have completed one year of habilitation, patient compliance, and modified Kuppuswamy Socio-Economic status.

CONCLUSION

The current data has aided in refining our institutional management protocols and predicting high-risk candidates who may need revision surgery in the future. Based on the data, all cochlear implantees and their families especially in the lower socio-economic strata, are now being meticulously educated about device care, the possible reasons for failures, and the importance of timely re-intervention.

Role of Immediate Pre-Operative Tympanometry in Cochlear Implantation: MERF Protocol and Experience

(1) To study the association between an immediate pre-operative tympanometric profile in patients undergoing cochlear implantation with their intraoperative findings. (2) To analyse the intraoperative middle ear findings that require a staged cochlear implantation in patients presenting with a B-type tympanogram. (3) To study the complications in this group of patients during the 1-year follow-up. This retrospective non-interventional cohort study is done over a period of 6 years. Bilaterally profound deaf children, less than 6 years of age, and no history of otitis media with effusion were included in the study. Children who met the inclusion criteria were divided into 4 groups based on their tympanometric profiles that are A, As, B, and C type tympanogram and, their intraoperative findings were categorized as normal, mild oedema, minimal granulation with mild oedema, moderate to extensive granulation with or without oedematous mucosa and glue. Then finally, depending on the intraoperative middle ear and mastoid finding, a single-stage surgery or a two stage surgery was decided upon. A total of 1025 patients were implanted during the study period, 975 patients met our inclusion criteria. In our series, we found a statistically significant difference (p < 0.0001) between the tympanograms and their respective intra-operative middle ear findings. A statistically significant difference was seen (p < 0.0001) between patients who underwent a single-stage cochlear implant and those who underwent a two-staged surgery, regarding their intraoperative middle ear findings. No statistical significance was seen in the occurrence of complications between the groups undergoing a single stage and a two-staged surgery (p > 0.5). This study showcases the importance of immediate pre-operative tympanometry in cochlear implant surgeries. Two-stage surgery is a decision taken on the operating table, depending on the extent of pathology and visibility of the round window niche.

Systematic review of cochlear implantation in adults with asymmetrical hearing loss

BACKGROUND

Rapid advances in cochlear implantation has witnessed an expanding spectrum for candidacy worldwide. This includes a subgroup of adults with asymmetrical hearing loss who have a wide range in their hearing capacity between the two ears. As per guidelines they are not included in mainstream candidacy for CI across the world. Evidence is now emerging to support the benefits of CI in AHL.

METHODS

This review analyzed literature regarding the outcomes of CI in AHL. Primary outcome measure was to assess audiological benefits and secondary outcome measure was to assess hearing related quality of life. 15 relevant articles, published worldwide between 2009 and 2019 were chosen. CASP checklist for systematic reviews was used to ascertain the quality of literature. The strength of recommendations from each study was analyzed and classified as strong, moderate, weak or none based on GRADE guidelines.

RESULTS

Heterogeneity in samples was obvious and samples varied largely between the studies. The levels of evidence ranged from systematic review to expert opinion, but overall they reflected positively on both audiological and QOL benefits.

CONCLUSION

CI provides important auditory and QOL benefits in AHL, but there is no high level evidence as yet to strongly support CI for AHL. A long term multi-centric study is necessary to influence a change in practice for a growing population of AHL.Trial registration: ClinicalTrials.gov identifier: NCT03052920.

Satellite habilitation centres following cochlear implantation - Are they the way ahead in improving outcomes in developing countries?

INTRODUCTION

Cochlear implantation is a safe surgery for restoration of hearing in profoundly deaf children. Following cochlear implantation, children undergo rehabilitation (or 'habilitation' for those without previous hearing). The device is programmed after the surgery, so that the user can hear sounds through it and through rehabilitation training, the heard sounds are made to understand.

OBJECTIVE

Our study was aimed at analysing the role of satellite habilitation centres following cochlear implantation by analysing the outcomes following habilitation and comparing it with the outcomes of the main centre and correlating it with the percentage of attendance of classes. Our study also aims to compare the attendance of implant patients from outside the geographical area of the main centre before and after starting the satellite centre.

MATERIALS AND METHODS

1004 profoundly deaf children (6 years and below) who had undergone cochlear implantation and completed 12months of habilitation in our institution from July 2013 to December 2019 were retrospectively analysed. The outcomes of all the centres were assessed by comparing the baseline CAP with CAP scores at 12 months and baseline SIR with SIR scores at 12 months. The outcomes of the main centre and satellite centres were also compared. The outcomes were correlated with percentage of attendance of classes.

OBSERVATION

The overall attendance in all the centres was between 75 and 80%. Both main and satellite centres showed statistically significant good outcomes and this correlates with percentage of attendance.

CONCLUSION

Satellite centres for habilitation across the state has greatly helped to improve the attendance of these patients and outcomes. Reduced drop-out rates and improved speech language outcomes can be achieved by starting satellite centres for habilitation post cochlear implantation in developing countries like India.

Audiological practice and COVID-19: recommendations that audiological centers can use to maintain the safety and quality of service-expert opinion

Purpose

Audiology is an essential service for some patient groups and some interventions. This article sets forth experience-based recommendations for how audiological centers can continue to safely and effectively function during COVID-19.

Methods

The recommendations are the result of panel discussion and are based on the clinical experience of the panelists/authors.

Results

The recommendations cover which patient groups and which interventions should be treated when and whether this can be performed in the clinic or remotely; how to maintain the safety of workplace via optimizing patient flow within the clinic and the sanitation of rooms and equipment; and overcoming communication challenges that COVID-19 intensifies.

Conclusion

For essential audiological services to continue under COVID-19, safety measures must be implemented and maintained, and treatment and communication strategies must be adapted to offset communication difficulties due to personal protective equipment (PPE) and social distancing and to bolster patient confidence. In short, it is vital that staff feel safe, that patients either feel the clinic is safe enough to visit or that remote treatment may be an option, and that clinics and patients have a broad agreement on the urgency of any needed service. We hope that these recommendations help clinics effectively accomplish these goals.

Comparison of Clinician Versus Parental Perspectives of Outcomes in Cochlear Implantees: A South Indian Experience

Outcomes of cochlear implantation (CI) are generically assessed using standard validated measures like CAP, SIR, MAIS and MUSS scales. Although this reflects the improvement in auditory verbal skills among the implantees with habilitation over one year, the overall perception of their skill development may vary between the parents of these children and the clinicians who provide the habilitation. This study aimed to compare the CAP and SIR scores sequentially over habilitation and further analyzes the correlation between clinician assessment (with CAP/SIR scores) and parental perspective (with MAIS/MUSS scores), at the end of one year of habilitation. 388 children aged 1-6 years who underwent unilateral CI were included in the study. Their baseline CAP and SIR scores were recorded post implantation. All children received 1 year of intensive auditory verbal therapy and their 12 month CAP, SIR, MAIS and MUSS scores were then recorded. The baseline CAP/SIR scores were compared with 12 month CAP/SIR scores and then their 12 month CAP/SIR scores were correlated with 12 month MAIS/MUSS scores respectively. There was significant difference between baseline and the 12 month CAP/SIR scores (p < 0.001). There was strong positive correlation between CAP and SIR scores after 12 months of habilitation (r = 0.7), while there was moderate positive correlation between CAP and MAIS scores (r = 0.59) and between SIR and MUSS scores (r = 0.49) respectively. Though the parents note significant improvement in child's communication abilities, the parental perspective of final outcomes does not always match with the clinician's assessments at the end of habilitation, as highlighted by the moderate correlations. A more precise method of holistic assessment is lacking currently and stands warranted.

Audiological and Surgical Outcomes of Pediatric Cochlear Implantation in Mondini's Dysplasia: Our Experience

OBJECTIVES

Aim of present study is to compare audiological and surgical outcomes in prelingual deaf children with Mondini's dysplasia (MD) and those with normal inner ear anatomy.

MATERIALS AND METHODS

Retrospective data was collected from Jan 2008 to Dec 2016. Children with bony IEM other than MD, syndromic association, multiple disabilities, those lost to follow up, and perilingual or postlingual deafness were excluded from study. Audiological outcomes for auditory perception (CAP score) and speech intelligibility (SIR score) was noted for a follow up period of 1 year.

RESULTS

Mean age at implantation was 2.8 years (Range of 2 to 6 years). 2 patients had intraoperative CSF ooze which was controlled intraoperatively by conservative measures. Post operative facial nerve function was normal in all patients. None of the patient in either group had any complications at one year of follow up period. There was statistically significant improvement in CAP - SIR score in Group A at 6 - 12 months compared to pretreatment. There was no statistically significant difference between the 2 groups in terms of CAP - SIR score at 6 - 12 months.

CONCLUSION

The study stresses the fact that cochlear implantation can be safely performed in children with MD although there is a risk of intraoperative CSF leak which can be controlled intraoperatively. Cochlear implantation in children with MD has good surgical, auditory and speech outcomes at par with children with normal bony inner ear anatomy.

Quality of life assessment in paediatric cochlear implant recipients in South India: Parental assessment and correlation with rehabilitation scores using a bilingual quality of life assessment questionnaire

Objectives: To assess the quality of life (QoL) of prelingually deaf paediatric population after Cochlear implantation (CI), using a bilingual questionnaire and to correlate with rehabilitation scores; to validate the questionnaire and recommend its use in future studies.Methods: This was a questionnaire based cross-sectional study. Parents of 151 paediatric prelingual CI recipients filled the questionnaire using a 5-point rating scale, with a score of 1-5. These scores were correlated with the CAP and SIR scores.Results and discussion: There was a positive correlation of QoL score with rehabilitation outcomes (r = 0.4638 and P ≤ 0.00001 for CAP; r = 0.3563 and P ≤ 0.00001 for SIR scores). The maximum scores (≥4.0) were given by parents for integration into educational system (4.86), response to environmental sounds (4.12) and overall parental satisfaction about child's performance (4.09). Minimum scores were given for ability to speak in sentences (2.9) and response to verbal sounds at a distance (3.23).Conclusion: The QoL of these children as assessed by the institutional questionnaire have correlated with the rehabilitation outcomes. These QoL results have a positive impact in counselling for early CI as well as for rehabilitation.

A clinical profile of revision cochlear implant surgery: MERF experience

Objective: To study the prevalence of revision cochlear implant study in a tertiary care referral center. To assess the various indications and surgical outcomes of revision cochlear implant surgery. Methods: A retrospective chart review of revision cochlear implant surgery done from June 1997 to December 2019. All the surgeries that were done in children of 12 years and below were included. The revision surgeries were either with or without explantation and reimplantation. The causes included were device failures, electrode extrusion/malposition, magnet migration, persistent foreign body reaction, facial twitching, wound infection, and cholesteatoma. Results: A total of 1636 pediatric cochlear implantation surgery were performed during the study period of 22 years. There were 94 (5.7%) revision surgeries done for various indications during this period. Out of them, 67 patients (71.3%) had device failure thus being the commonest indication for revision surgery, followed by infection in 12.8% of the total patients. Among the total revision, 81 (86.2%) patients had explantation and reimplantation of the new device. Conclusion: Indications of revision cochlear implant surgery are manifold that can be either device-related or patient-related. Revision surgery needs a highly skilled and experienced team of surgeons, audiologists, and habilitationists for achieving optimal results.

A Study of Outcome of Pediatric Cochlear Implantation in Patients with Cochleovestibular Nerve Deficiency

OBJECTIVES

A cochleovestibular nerve deficiency (CVND) could compromise stimulation of nerve by electrical pulses delivered from a cochlear implant, thereby hindering activity along auditory pathway. The evaluation of children with congenital hearing loss with a high-resolution magnetic resonance imaging is presently the investigative modality of choice to diagnose CVND. The aim of this study was to determine the outcomes in pediatric cochlear implant recipients with a diagnosis of CVND. The objectives included (1) to study the prevalence of CVND among children with prelingual congenital severe to profound hearing loss; (2) to assess post cochlear implantation (CI) outcomes in children with CVND using categories of auditory performance (CAP), speech intelligibility rating (SIR), and cortical auditory evoked potentials (CAEPs); and (3) to propose a management protocol for these children.

MATERIALS AND METHODS

All CI procedures performed during the study period in children 5 years or younger were included in study. All patients who were older than 5 years or had syndromic associations, multiple disabilities, second side or revision CI were excluded from the study. Children with unilateral cochleovestibular nerve aplasia and all other cases of CVND (type IIa and IIb) were advised to undergo CI on side with more radiologically robust nerve and/or cochlea anatomy. Children with bilateral CVND were included in group A, and age-matched cochlear implant candidates with normal cochleovestibular nerve anatomy were included in group B for statistical comparison of outcomes.

RESULTS

In group A, post CI CAP and SIR, CAEP amplitude and latency at 12 months showed statistically significant difference (p<0.05) compared with preoperative values. However, mean score of CAEP latency and amplitude and SIR score was worse for group A compared with group B at 12 months, which was statistically significant (p<0.05).

CONCLUSION

This study supports the fact that CI is a viable option to be offered in children with CVND (type IIa and IIb) for the development of auditory perception and speech.

Posterior semi-circular canal electrode misplacement in Goldenhar's syndrome

Literature documents the incidence of electrode misplacement within the range of 0.2% to 5.8% with the superior SCC as the most common site, followed by the vestibule. In this report, we present the finding of electrode misplacement in the posterior SCC in a child with Goldenhar syndrome which was subsequently corrected. This child with bilateral congenital profound SNHL presented for unilateral cochlear implant surgery. Intraoperatively, the lateral SCC bulge, stapes, oval window, round window niche and pyramid were noted absent, leading to a surgical decision in favour of a subtotal petrosectomy. Using the aberrant facial nerve and jugular bulb as critical landmarks, a cochleostomy was performed in the posteroinferior aspect of the promontory bulge. Although electrode insertion was smooth and complete, NRT was absent in the presence of normal electrode impedance. A post-operative HRCT scan showed the electrodes in the posterior SCC. Repositioning of the electrodes was carried out by creating a new cochleostomy anteroinferior to the previous one. Complete correct electrode insertion was accomplished via this cochleostomy complimented by robust NRT tracings. Cochlear implant electrode insertion should be supported by correct identification of surgical landmarks. Intraoperative impedance testing and NRT help confirm device integrity and correct placement, the absence of which may raise the suspicion of malposition. In the presence of such a suspicion, the post-operative HRCT scan is a useful retrospective guide to corrective action, in a low-cost setting lacking intra-operative imaging facilities like X-ray, Fluoroscopy, Flat Panel CT & CBCT. Abbreviations, BERA: Brainstem Evoked Response Audiometry; CBCT: Cone Beam Computed Tomography; EAC: External Auditory Canal; ITD: Insertion Test Device; LSCS: Lower Segment Caesarean Section; MDT: Multi-Disciplinary Team; NICU: Neonatal Intensive Care Unit; NRT: Neural Response Telemetry; OAE: Oto-Acoustic Emissions; PIH: Pregnancy Induced Hypertension; SCC: Semi-Circular Canal; SNHL: Sensori-Neural Hearing Loss.

Subtotal Petrosectomy in Cochlear Implant Surgery: Our Experience

Aims

Subtotal petrosectomy (SP) with cochlear implant (CI) is required in certain specific situations in the management of patients who are candidates for cochlear implants. To study and review the indications, surgical issues, and complications of this procedure.

Materials and Methods

Retrospective review of all patients who underwent subtotal petrosectomy with cochlear implant during the period January 2010-December 2016 at a tertiary care and referral centre.

Results

19 patients underwent 20 subtotal petrosectomy with cochlear implant during this period. One patient had simultaneous bilateral implantation. The indications were previous mastoid cavity in 7 patients, 5 patients had chronic otitis media, inner ear malformations in 3,ossified cochlea in 3 and unfavourable anatomy in 2 patients. Fat or musculoperiosteal flaps were used to obliterate the cavity. Ninety percent of patients underwent single stage surgery and ten percent underwent two stage procedure.Complications were seen in three patients (15%).

Conclusion

SP helps in isolating the cavity from external environment after removal of disease, improves the exposure and access, reduces risk of infection and cerebrospinal fluid (CSF) leaks and facilitates CI. Meticulous surgical technique will reduce the complications and long term follow up is needed to detect entrapped cholesteatoma. Subtotal petrosectomy with blind sac closure of external ear canal is required in certain specific situations. It is a safe and effective surgery with acceptable rate of complications.

Bilateral Bone Anchored Hearing aids: A Case Report on Right Side Percutaneous and Left Side Transcutaneous Implant

Bilateral Bone Anchored Hearing Aids (BAHA) provide more subjective patient satisfaction and outcome than unilateral BAHA. Initially, percutaneous BAHAs were used for many decades. Transcutaneous BAHAs were started later to overcome problems associated with percutaneous ones. The present report gives the outcome of bilateral BAHA in a patient with percutaneous BAHA on one side and transcutaneous BAHA on the other.

The reliability of hearing implants: report on the type and incidence of cochlear implant failures

Objectives: This study presents the data collected through a database on the type and incidence of cochlear implant device failures and major complications and quantifies the risk of failures across time based on the Association for the Advancement of Medical Instrumentation (AAMI) CI86:2017 standard. Methods: Information on reliability of MED-EL cochlear implants was collected from the MED-EL complaint database between 2003 and2013. Explants were categorized and device reliability was calculated according to the AAMI CI86:2017 standard principles. Results: Data were collected for 11662 devices (5462 children, 6200 adults). The mean duration of follow up was 46.16 months. The total failure rate for all devices and all subjects was 2.41%. Medical related explants (MRE) were significantly worse for children than for adults with the ceramic implants, C40+ (p = 0.008) and PULSAR (p = 0.020). Device failure explants (DFE) were significantly worse for children than for adults with all four devices in the study, the C40+ (p < 0.001), PULSAR (p < 0.001), SONATA (p < 0.001), and CONCERTO (p = 0.023). The mean annual failure rate for all subjects and devices was 0.63% (1.03% for children, 0.28% for adults). The mean annual failure rate was 0.90% for the C40+; 0.57% for the PULSAR; 0.46% for the SONATA; and 0.39% for the CONCERTO. Conclusions: Compared to adults, children had significantly worse MRE and DFE due to a higher risk of head trauma and more vulnerable skull anatomy. Further, the authors conclude that the AAMI standard will ensure a more comprehensive and transparent evaluation of cochlear implant reliability in the future.

Cochlear Implantation in Children with Usher's Syndrome: A South Asian Experience

Usher's syndrome is an autosomal recessive disorder characterized by dual sensory impairment involving both the ears and eyes. Cochlear implantation paves a way to restore hearing loss in such individuals but poor vision among these patients poses additional challenges for the habilitationists. This study aimed to compare the habilitation outcomes and hearing-related quality of life scores of cochlear implantees having Usher syndrome with age-matched cochlear implantees with no such syndromic association. 27 patients aged 1-6 years with Usher syndrome underwent cochlear Implantation over a period of 10 years from 2006 to 2016 and were included in this study along with an age-matched cohort of 30 implantees with no additional disabilities. Category of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores were compared at 3, 6, 9 and 12 months respectively. Glasgow Benefit Inventory and Health Utility Index (HUI 3.0) questionnaires were used to assess the hearing-related quality of life in both groups at 1 year post implantation. There was significant difference in CAP and SIR scores between children with Usher's syndrome and the control group (p < 0.05). The overall scores in terms of quality of life as well were statistically different (p < 0.05). Though there was improvement in speech and language acquisition after cochlear Implantation this was found to be of lesser extent than the normative cohort. These children with additional visual disabilities required intensive, individualized therapy catering to their complex needs. Their family's perception of expected benefit from cochlear Implantation was guarded and needed to be appraised in detail prior to surgery. This experience helped prepare an institutional protocol for counseling such implantees in future.

Cochlear Implantation in Congenital Long-QT Syndrome: A Comprehensive Study

OBJECTIVES

Jervell and Lange-Nielsen syndrome is a rare autosomal recessive disease characterized by congenital sensorineural deafness and significant QT interval prolongation. Aims were to study the prevalence of long QT in congenital hearing loss, complications encountered, outcomes by Categories of auditory Performance (CAP) scores and Speech Intelligibility Rating (SIR) scores and to create an algorithm with precautions to be followed in Long QT children.

MATERIALS AND METHODS

Study was done at Auditory implant center at a tertiary referral care ENT hospital which includes 41 paediatric patients who were diagnosed to have Long QT during preoperative assessment and underwent cochlear implantation. A standard Protocol was followed in all candidates which includes comprehensive targeted history and investigations, preoperative and intraoperative precautions, and the findings were recorded.

RESULTS

Preoperative prophylactic Beta blockers, avoiding sympathetic stimulation and drugs prolonging QT interval with rational use of Magnesium Sulphate and standby of defibrillator were the standard precautions practised. Fatal Arrhythmias were encountered intra-operatively in five patients which was treated with cardiac pacing. Cardiac monitoring was done intraoperatively and during switch-on. Significant improvement in CAP and SIR scores were observed at 3 and 6 months when compared to their base line values.

CONCLUSION

With special attention to preoperative evaluation, appropriate intraoperative precautions and monitoring, judicious surgical planning and post surgical follow-up cochlear implantation may be performed safely in patients with JLNS with good postoperative results allowing for improved audition.

Expanding Access: Cost-effectiveness of Cochlear Implantation and Deaf Education in Asia

Objective

To determine the cost-effectiveness of cochlear implantation (CI) with mainstream education and deaf education with sign language for treatment of children with profound sensorineural hearing loss in low- and lower-middle income countries in Asia.

Study Design

Cost-effectiveness analysis.

Setting

Bangladesh, Cambodia, India, Indonesia, Nepal, Pakistan, Philippines, and Sri Lanka participated in the study.

Subjects and Methods

Costs were obtained from experts in each country with known costs and published data, with estimation when necessary. A disability-adjusted life-years model was applied with 3% discounting and 10-year length of analysis. A sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and probability of device failure. Cost-effectiveness was determined with the World Health Organization standard of cost-effectiveness ratio per gross domestic product (CER/GDP) per capita <3.

Results

Deaf education was cost-effective in all countries except Nepal (CER/GDP, 3.59). CI was cost-effective in all countries except Nepal (CER/GDP, 6.38) and Pakistan (CER/GDP, 3.14)—the latter of which reached borderline cost-effectiveness in the sensitivity analysis (minimum, maximum: 2.94, 3.39).

Conclusion

Deaf education and CI are largely cost-effective in participating Asian countries. Variation in CI maintenance and education-related costs may contribute to the range of cost-effectiveness ratios observed in this study.

A Retrospective Study of Cochlear Re-Implantations - Experience from a Large Centre in India

Objective

Cochlear re-implantation (CRI) is becoming increasingly common throughout the world. However, studies regarding CRI incidence and etiology are lacking from developing countries like ours. The aim of this study was to present the Indian experience with CRI based on our experience. Objectives were to determine the incidence and the indications of CRI and the cumulative survival rate (CSR) of cochlear implantation (CI).

Methods

Our study was a retrospective one, conducted at a tertiary care centre in southern India. 1,500 consecutive cochlear implanted ears from 1997 to 2016 were studied. All patients who underwent CRI during this period were included in the study.

Results

There were a total of 53 ears (31 male and 22 female ears) who underwent CRI. This gives an incidence of 3.53%. The most common indication of CRI was device failure in 39 ears contributing to 73.6% of the total CRI. The overall CSR of CI in pediatric population was 96.5% over a 20-year period.

Conclusion

The CRI incidence and etiology at our centre appears to reflect the findings of the literature. Cochlear implant centres across the world should report the CSR of devices used at their respective centres so that it can be made an important criterion in choice of implant.

Paediatric auditory brainstem implantation: The South Asian experience

INTRODUCTION

Paediatric Auditory Brainstem Implantation (ABI) is indicated for children with congenital cochlear aplasia, absent/hypoplastic vestibulocochlear nerve, for whom cochlear implantation is not possible. Knowledge of the anatomical landmarks and variants in anatomy of the brainstem is vital for ABI surgery.

METHOD

Study was done at Auditory implant centre in Madras ENT research foundation, which includes 24 children who had undergone ABI surgery and are being followed up for 1 year, post operatively. Aims were to study the anatomical variants and the outcomes of ABI implantation. To determine if different anatomical variants effect placement of ABI electrode. To assess the patient outcomes by Categories of auditory Performance (CAP) scores and Speech Intelligibility Ratings (SIR) scores.

RESULTS

All the candidates showed gradual improvement in audiological and verbal outcomes after the ABI. The mean CAP and SIR scores after 6 months of AVHT were 2.07 and 1.37 respectively. After 1 year of auditory verbal rehabilitation therapy CAP was 3.42 and SIR was 2.33. Flocculus of the cerebellum can be of different grades. Though, there was difficulty in insertion of the electrode in subjects with anatomical variants, the outcomes were comparable with other subjects.

CONCLUSION

ABI surgery involves frequent anatomical variations surrounding the lateral recess which makes the positioning of the auditory prosthesis difficult. Variants during the surgery can make the placement of ABI electrodes difficult, but promising results were seen all the implantees.

Surgical anatomy of lateral recess in paediatric auditory brainstem implant patients and its clinical correlates including grades of flocculus

INTRODUCTION

Auditory brainstem implant (ABI), a standard technique in treatment of profound sensorineural hearing loss in patients with neurofibromatosis 2, is now being increasingly employed in children with congenital bilateral sensorineural hearing loss, as in Michele's deformity. A detailed knowledge of the relevant surgical anatomy of the lateral recess and its anatomical landmarks including the flocculus, the choroid plexus and the root entry zones of facial-vestibulocochlear and glossopharyngeal-vagus nerve complexes and their anatomical variants is mandatory, as it is the conduit for electrode array placement. The placement of electrode may be eased or impeded by these variations.

MATERIALS AND METHODS

Thirty-two children with congenital bilateral hearing loss underwent surgery through retromastoid suboccipital approach for placement of auditory brainstem implant. The preoperative anatomy was reviewed in detail during procedure and again later in the operative videos.

RESULTS

The flocculus was classified into four grades based on its anatomy and relations. Among these, grade II (11 children) was the commonest while grade IV (five children) was least common. Choroid plexus was variable in size across grades of flocculus. Difficulty in defining the anatomy was significantly more (p value = 0.003) in the group with higher grade flocculus (grade III and IV) than in lower grade flocculus (grade I and II).

CONCLUSION

The flocculus in these patients is classifiable into one of the four grades and the surgical nuances such as difficulty in defining the anatomy for placement of ABI are dependent on the characteristics exhibited by the floccular anatomy and relations.

Outcomes of Cochlear Implantation in Auditory Neuropathy Spectrum Disorder and the Role of Cortical Auditory Evoked Potentials in Benefit Evaluation

Objective

To compare the outcomes of cochlear implantation (CI) in children with auditory neuropathy spectrum disorder (ANSD) and age-matched controls with profound sensorineural hearing loss, using categories of auditory performance (CAP), speech intelligibility rate (SIR), meaningful auditory integration scale (MAIS), and meaningful use of speech scale (MUSS), and to determine the role of Cortical Auditory Evoked Potentials (CAEP) in benefit evaluation after CI.

Methods

Ten patients (8 males and two females) with ANSD who underwent CI were included in the study. Auditory and speech scores were compared between baseline and after 12 months of habilitation in children with ANSD. Post CI speech scores in children with ANSD were compared with the control group (age-matched children with profound sensorineural hearing loss) at 12 months of habilitation. P1 latency of CAEP has a good correlation with auditory and speech scores in children with ANSD in the study group.

Results

Significant benefits were seen in children with ANSD who underwent CI compared to the baseline CAP and SIR scores and one year after habilitation. There is no statistically significant difference in outcomes between the two groups with CI (ANSD and profound sensorineural hearing loss) (p-value: CAP=1.00, SIR=0.84, MAIS=0.33, MUSS=0.08). Speech perception in noise test (SPIN) scores in children with ANSD were 63% and 80% with 0 dB signal noise ratio (SNR) and +10dB SNR, respectively. P1 wave of CAEP has a good correlation with the subjective outcomes.

Conclusion

CI in children with ANSD has showed benefits comparable to children with profound sensorineural hearing loss. CAEP is a useful tool in objectively assessing cortical maturity in children with ANSD following CI.

Audit of Bilateral Simultaneous Cochlear Implantation in Pediatric Population: South Indian Study

Objective

To conduct a medical audit of bilateral simultaneous cochlear implantation (CI) in patients with severe prelingual sensorineural hearing loss (SNHL).

Methods

A medical audit of a tertiary care ear, nose, and throat center in Southern India was conducted on data collected from January 2007 to December 2014. All cochlear implantees <6 years of age with severe bilateral SNHL who underwent bilateral simultaneous CI were included in the present study. The exclusion criteria were children >6 years, sequential bilateral CI, revision cases, abnormal or malformed cochlea, and children with global developmental delay in milestones. Subjective outcome scores used were Category of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR).

Results

The CAP and SIR results showed that 20% of implantees achieved peak scores of 7 and 5, respectively. Mean CAP and SIR scores at 12 months were 5.4 and 3.1, respectively.

Conclusion

The present study supports the claim that bilateral CI in severe prelingual bilateral SNHL is better than unilateral and recommends that bilateral CI should be the standard of care in children.

Translabyrinthine approach to internal auditory meatus: A retrospective study

Background

Ear and the lateral skull base surgery is challenging and yet fascinating for a Neuro-otologist. A thorough knowledge of the complex anatomy is indispensable for the surgeon in order to provide the best possible care.

Methods

The aim of the study was to highlight the present day indications for translabyrinthine approach to IAM from a Neuro-otologist perspective.

Results

There were a total of 7 patients who underwent Translabyrinthine approach at our centre. In the present study we have reported cases of Vestibular Schwannoma, Facial nerve schwannoma, Cholesteatoma involving the IAM, Meniere's disease with refractory vertigo which were managed via translabyrinthine approach. We also encountered, probably the first reported case, tuberculoma of the IAM which was clinical suspected to be vestibular schwannoma.

Conclusion

The article presents different clinical situations where this approach can be suitably utilized and has been dealt with via a retrospective study encountered at our centre.

Does cerebellar flocculus size affect subjective outcomes in pediatric auditory brainstem implantation

OBJECTIVES

The objectives of study was to 1) Describe relevant surgical anatomy in defining and accessing the lateral recess for placement of electrode, 2) Propose a working classification for grades of Flocculus; 3) To determine if different grades of cerebellar flocculus effects placement of ABI electrode and subjective outcomes in implantees.

METHODS

Our study was a prospective study, and comprised of cohort of 12 patients who underwent ABI surgery via retrosigmoid approach between 1 Jan 2012 to 31 Dec 2014. All children with congenital profound sensorineural hearing loss with either absent cochlea or cochlear nerve were included in the study. Relevant anatomy was noted. We also noted down the difficulty encountered during the placement of ABI electrode. Auditory perception and speech intelligibility was scored post operatively for 1 year.

RESULTS

Cerebellar flocculus was divided into 4 grades depending on the morphology of cerebellar flocculus. It was noted that Grade 3 & 4 flocculus (Group B) had difficult ABI electrode placement in comparison to Grade 1 & 2 flocculus (Group A). The subjective outcomes of Group A was better than Group B. However the p value was not statistically significant.

CONCLUSION

Cerebellar flocculus can be graded depending on morphology and size. Flocculus of higher grades can make the placement of ABI electrodes difficult and adversely effects the postoperative subjective outcomes.

Towards a Unified Testing Framework for Single-Sided Deafness Studies: A Consensus Paper

BACKGROUND

While hearing aids for a contralateral routing of signals (CROS-HA) and bone conduction devices have been the traditional treatment for single-sided deafness (SSD) and asymmetric hearing loss (AHL), in recent years, cochlear implants (CIs) have increasingly become a viable treatment choice, particularly in countries where regulatory approval and reimbursement schemes are in place. Part of the reason for this shift is that the CI is the only device capable of restoring bilateral input to the auditory system and hence of possibly reinstating binaural hearing. Although several studies have independently shown that the CI is a safe and effective treatment for SSD and AHL, clinical outcome measures in those studies and across CI centers vary greatly. Only with a consistent use of defined and agreed-upon outcome measures across centers can high-level evidence be generated to assess the safety and efficacy of CIs and alternative treatments in recipients with SSD and AHL.

METHODS

This paper presents a comparative study design and minimum outcome measures for the assessment of current treatment options in patients with SSD/AHL. The protocol was developed, discussed, and eventually agreed upon by expert panels that convened at the 2015 APSCI conference in Beijing, China, and at the CI 2016 conference in Toronto, Canada.

RESULTS

A longitudinal study design comparing CROS-HA, BCD, and CI treatments is proposed. The recommended outcome measures include (1) speech in noise testing, using the same set of 3 spatial configurations to compare binaural benefits such as summation, squelch, and head shadow across devices; (2) localization testing, using stimuli that rove in both level and spectral content; (3) questionnaires to collect quality of life measures and the frequency of device use; and (4) questionnaires for assessing the impact of tinnitus before and after treatment, if applicable.

CONCLUSION

A protocol for the assessment of treatment options and outcomes in recipients with SSD and AHL is presented. The proposed set of minimum outcome measures aims at harmonizing assessment methods across centers and thus at generating a growing body of high-level evidence for those treatment options.

Knowledge, Attitudes and Practices Relating to Vertigo among Newly Diagnosed Patients: Findings of a Prospective, Observational Registry in India

OBJECTIVE

Vertigo is a common complaint in clinical practice, with multi-causative etiology, substantially impacting individual's overall lifestyle and behavior. However, so far no much data is available to understand the knowledge, attitude and practices (KAP) about vertigo in newly diagnosed Indian patients. Hence, the objective of this prospective, non-interventional, observational registry was to evaluate KAP towards vertigo and assessment of their awareness through a questionnaire-based survey.

METHODS

Newly diagnosed patients with vertigo (aged ≥18 years), visiting the physicians, were provided with a self-administered validated questionnaire with domains namely knowledge (18 questions), attitude (7 questions), and practices (8 questions). Primary objective was to analyze the percentage of patients with high, average and low level of knowledge; percentage of patients who were little, quiet and extremely concerned about vertigo and its treatment; percentage of patients taking high, moderate and poor level of precaution towards vertigo. All variables were subjected to statistical analysis.

RESULTS

Overall, 1167 (76.8%) patients completed the KAP questionnaire (women: 52.9%; men: 47.1%). A total of 17.3% patients had low level of knowledge, 73.9% had average and 8.74% patients had high level of knowledge regarding vertigo. Attitude domain revealed that majority of the patients (86.20%) had little concerned attitude towards vertigo; 9.85% patients were extremely concerned and 3.94% patients were not concerned regarding vertigo. Practice domain revealed that none of the patients took high level of precautions, 79.8% patients took moderate precautions and 20.2% took less precaution for disease prevention.

CONCLUSIONS

This study revealed that the knowledge, attitude and practice patterns amongst Indian vertigo patients are inadequate, highlighting the need for awareness and scientific education amongst these patients in India. Moreover, health care providers should be trained to provide counseling to these patients effectively.

Spectrum of DNA variants for non-syndromic deafness in a large cohort from multiple continents

Hearing loss is the most common sensory deficit in humans with causative variants in over 140 genes. With few exceptions, however, the population-specific distribution for many of the identified variants/genes is unclear. Until recently, the extensive genetic and clinical heterogeneity of deafness precluded comprehensive genetic analysis. Here, using a custom capture panel (MiamiOtoGenes), we undertook a targeted sequencing of 180 genes in a multi-ethnic cohort of 342 GJB2 mutation-negative deaf probands from South Africa, Nigeria, Tunisia, Turkey, Iran, India, Guatemala, and the United States (South Florida). We detected causative DNA variants in 25 % of multiplex and 7 % of simplex families. The detection rate varied between 0 and 57 % based on ethnicity, with Guatemala and Iran at the lower and higher end of the spectrum, respectively. We detected causative variants within 27 genes without predominant recurring pathogenic variants. The most commonly implicated genes include MYO15A, SLC26A4, USH2A, MYO7A, MYO6, and TRIOBP. Overall, our study highlights the importance of family history and generation of databases for multiple ethnically discrete populations to improve our ability to detect and accurately interpret genetic variants for pathogenicity.

Patient management for cochlear implant recipients in audiology departments: A practice review

OBJECTIVES

To determine and evaluate the time clinics needed to complete the sub-processes involved in the first-fitting and follow-up fitting of people with a cochlear implant.

METHODS

Eight HEARRING clinics completed a questionnaire recording how long it took to complete the sub-processes involved in first-fitting and follow-up fitting cochlear implant recipients. The mean times of clinics and procedures were then compared.

RESULTS

Questionnaires on 77 patients were completed. Clinics varied widely on time spent on each sub-process in both first- and follow-up fittings. Total first-fitting times were similar across clinics. Follow-up fitting times varied more across clinics although this may have been due to differences in questionnaire interpretation.

DISCUSSION

If a patient management plan can help increasingly busy cochlear implant clinics provide high-quality care more efficiently, essential first steps are determining which procedures are generally performed and how long their performance takes. Until reliable data are gathered, constructing a patient management plan or reaping the potential benefits of its use will remain elusive; clinics will have to find what solutions they can to meet rising workload demands.

CONCLUSION

The variation in time spent on each sub-process may suggest that some clinics have more efficient workflow procedures. Compiling a best practice for each process could be instrumental in creating a professional process management plan that would increase efficiency without sacrificing quality of care.

Genetics: A New Frontier in Otology

Molecular genetics is a rapidly expanding field with possibilities for novel diagnostic and treatment strategies for otological diseases. Gene therapy, if theory is proven practical, could eliminate disease at the molecular level, thus obviating the need for pharmacologic or surgical treatment. Recent years have seen great advances in our understanding of the molecular genetic basis of many otological disorders. Building on the success of the Human Genome Project, new technologies are in development to identify disease-causing mutations through genetic testing. A basic understanding of the genetic basis of Otological diseases is crucial to the practising Otologist and the time has come for genetic services to be incorporated into regular Otological clinics.

Quality standards for bone conduction implants

CONCLUSION

Bone conduction implants are useful in patients with conductive and mixed hearing loss for whom conventional surgery or hearing aids are no longer an option. They may also be used in patients affected by single-sided deafness.

OBJECTIVES

To establish a consensus on the quality standards required for centers willing to create a bone conduction implant program.

METHOD

To ensure a consistently high level of service and to provide patients with the best possible solution the members of the HEARRING network have established a set of quality standards for bone conduction implants. These standards constitute a realistic minimum attainable by all implant clinics and should be employed alongside current best practice guidelines.

RESULTS

Fifteen items are thoroughly analyzed. They include team structure, accommodation and clinical facilities, selection criteria, evaluation process, complete preoperative and surgical information, postoperative fitting and assessment, follow-up, device failure, clinical management, transfer of care and patient complaints.

The Genetic Basis of Nonsyndromic Hearing Loss in Indian and Pakistani Populations

Deafness encompasses a series of etiologically heterogeneous disorders with mutations in more than 400 independent genes. However, several studies indicate that a large proportion of both syndromic and nonsyndromic forms of deafness in the racially diverse Indian and Pakistani populations are caused by defects in just a few genes. In these countries, there is a strong cultural preference for consanguineous marriage and an associated relatively high prevalence of genetic disorders. The current Indian population is approximately 1.2 billion and it is estimated that 30,000 infants are born with congenital sensorineural hearing loss (HL) each year. The estimated rate of profound bilateral HL is 1.6 per 1000 in Pakistan and 70% of this HL arises in consanguineous families. Knowledge of the genetic cause of deafness within a distinct population is important for accurate genetic counseling and early diagnosis for timely intervention and treatment options. Many sources and technologies are now available for the testing of hearing efficiency. Population-based screening has been proposed as one of the major strategies for translating genetic and genomic advances into population health gains. This review of the genetics of deafness in Indian and Pakistani populations deals with the major causes of deafness in these countries and prospectives for reducing the incidence of inherited deafness.

Syndromic deafness-prevalence, distribution and hearing management protocol in Indian scenario

BACKGROUND

The estimated prevalence of Sensory Neural Hearing Loss (SNHL) in patients less than 18 years of age is 6 per 1000. Roughly 50% of cases of congenital SNHL can be linked to a genetic cause, with approximately 30% being syndromic and the remaining 70% being non-syndromic. The term "syndromic" implies the presence of other distinctive clinical features in addition to hearing loss. The aim of our study was to find the distribution of various Syndromic associations in patients with profound deafness, presented at Madras ENT Research foundation, Chennai and to formulate a management protocol for these patients and to discuss in detail about the clinical features of commonly encountered syndromic deafness.

MATERIALS AND METHODS

Our retrospective study was aimed at describing the various Syndromic associations seen in patients with congenital profound deafness. Information was collected from the medical records. At our centre all patients undergo a comprehensive evaluation. The distribution, etiological factors and management protocol for various syndromes are here presented.

RESULTS

Out of 700 patients with congenital profound deafness all patients with Syndromic associations (n = 35) were studied. 5% of profoundly deaf candidates were found to be syndromic. Most common syndrome in our series was found to be congenital rubella syndrome followed by Jervell and Lange-Nielsen syndrome.

CONCLUSION

Congenital deafness is an associated feature of many syndromes. Detailed history taking with comprehensive evaluation is mandatory to rule out the associated syndromes. Diagnosis must be confirm by a genetic study. Multidisciplinary approach is essential for appropriate diagnosis and management.

Long term outcome of cochlear implantation in five children with common cavity deformity

INTRODUCTION

A common cavity (CC) deformity is a deformed inner ear in which the cochlea and vestibule are confluent forming a common rudimentary cystic cavity. The outcome of cochlear implantation (CI) in this deformity is not expected as good as in other cochlear deformity. Categories of Auditory Performance (CAP) score, Speech Intelligibility Rating (SIR) scale, Meaningful Auditory-Integration Scale (MAIS) and Meaningful Use of Speech Scale (MUSS) are scales designed to assess benefit of functional device (hearing aid, Cochlear implant, ABI) in young children. The aim of the study was to observe and report the long-term audiological progress and speech development of children with CC deformity after CI by means of CAP, SIR, MAIS, MUSS scores and CI aided threshold.

METHODS AND MATERIALS

The retrospective and prospective study was carried out in five Indian children with CC deformity who underwent CI from 2004 to 2010. Demographic data of onset and/or duration of deafness, age at implantation, time with hearing aids before implantation, duration with CI and co-morbidity were retrieved from a local data base. Their outcome score in audition and speech development on the basis of their CAP and SIR score at the end of 1 year of habilitation were collected. All the patients were called to follow up to obtain latest CI aided audiogram, CAP, SIR, MAIS and MUSS scores.

RESULTS

One male and four female children were detected with common cavity deformity among 258 deaf children of age below 6 years operated during study period. The CAP and SIR Scores increased from average of 0.4 and 1 to 3.4 and 2.4, respectively, over one year of habilitation. The CAP score improved in subsequent follow up to average of 5.0 after more than 3 years of follow up but the SIR score hardly improved. We assessed the MAIS and MUSS at last visit after 3 years. The mean of MAIS and MUSS was 32.4 and 26.4, respectively.

CONCLUSION

Though the habilitation outcome was not up to the mark in children with CC deformity, CI provides excellent awareness of environment sound and development of few words.