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.

Tuberculous otitis media: a resurgence?

OBJECTIVE: Tuberculosis is a global health problem that is especially prevalent in developing countries such as India. Recently, atypical presentation has become more common and a high index of suspicion is essential. This study analysed the various presenting symptoms and signs of tuberculous otitis media and the role of diagnostic tests, with the aim of formulating criteria for the diagnosis. METHODS: A total of 502 patients underwent tympanomastoidectomy over a two-year period. Microbiological and histopathological examinations and polymerase chain reaction analysis of tissue taken during tympanomastoidectomy were performed. RESULTS: A total of 25 patients (5 per cent) were diagnosed with tuberculous otitis media. Severe mixed hearing loss, facial palsy, labyrinthine fistula, post-aural fistula, perichondritis and extradural abscess were noted. CONCLUSION: There seems to be a resurgence in tuberculous otitis media in India. Microbiological, histopathological and polymerase chain reaction tests for tuberculosis are helpful for its diagnosis.

Electrophysiological Correlates of Behavioral Comfort Levels in Cochlear Implantees: A Prospective Study.

Indications for cochlear implantation have expanded today to include very young children and those with syndromes/multiple handicaps. Programming the implant based on behavioral responses may be tedious for audiologists in such cases, wherein matching an effective MAP and appropriate MAP becomes the key issue in the habilitation program. In 'Difficult to MAP' scenarios, objective measures become paramount to predict optimal current levels to be set in the MAP. We aimed, (a) to study the trends in multi-modal electrophysiological tests and behavioral responses sequentially over the first year of implant use, (b) to generate normative data from the above, (c) to correlate the multi-modal electrophysiological thresholds levels with behavioral comfort levels, and (d) to create predictive formulae for deriving optimal comfort levels (if unknown), using linear and multiple regression analysis. This prospective study included ten profoundly hearing impaired children aged between 2 and 7 years with normal inner ear anatomy and no additional handicaps. They received the Advanced Bionics HiRes 90K Implant with Harmony Speech processor and used HiRes-P with Fidelity 120 strategy. They underwent, Impedance Telemetry, Neural Response Imaging, Electrically Evoked Stapedial Response Telemetry and Electrically Evoked Auditory Brainstem Response tests at 1, 4, 8 and 12 months of implant use, in conjunction with behavioral Mapping. Trends in electrophysiological and behavioral responses were analyzed using paired t test. By Karl Pearson's correlation method, electrode-wise correlations were derived for NRI thresholds versus Most Comfortable Levels (M-Levels) and offset based (apical, mid-array and basal array) correlations for EABR and ESRT thresholds versus M-Levels were calculated over time. These were used to derive predictive formulae by linear and multiple regression analysis. Such statistically predicted M-Levels were compared with the behaviorally recorded M-Levels among the cohort, using Cronbach's Alpha Reliability test method for confirming the efficacy of this method. NRI, ESRT and EABR thresholds showed statistically significant positive correlations with behavioral M-Levels, which improved with implant use over time. These correlations were used to derive predicted M-Levels using regression analysis. Such predicted M-Levels were found to be in proximity to the actual behavioral M-Levels recorded among this cohort and proved to be statistically reliable. When clinically applied, this method was found to be successful among subjects of our study group. Although there existed disparities of a few clinical units, between the actual and predicted comfort levels among the subjects, this statistical method was able to provide a working MAP, close to the behavioral MAP used by these children. The results help to infer that behavioral measurements are mandatory to program cochlear implantees, but in cases where they are difficult to obtain, this study method may be used as reference for obtaining additional inputs, in order to set an optimal MAP. The study explores the trends and correlations between electrophysiological tests and behavioral responses, recorded over time among a cohort of cochlear implantees and provides a statistical method which may be used as a guideline to predict optimal behavioral levels in difficult situations among future implantees. In 'Difficult to MAP' scenarios, following a protocol of sequential behavioral programming, in conjunction with electrophysiological correlates will provide the best outcomes.

A clinical study of electrophysiological correlates of behavioural comfort levels in cochlear implantees.

OBJECTIVES: Indications for cochlear implantation have expanded today to include very young children and those with syndromes/multiple handicaps. Programming the implant based on behavioural responses may be tedious for audiologists in such cases, wherein matching an effective Measurable Auditory Percept (MAP) and appropriate MAP becomes the key issue in the habilitation program. In 'Difficult to MAP' scenarios, objective measures become paramount to predict optimal current levels to be set in the MAP. We aimed to (a) study the trends in multi-modal electrophysiological tests and behavioural responses sequentially over the first year of implant use; (b) generate normative data from the above; (c) correlate the multi-modal electrophysiological thresholds levels with behavioural comfort levels; and (d) create predictive formulae for deriving optimal comfort levels (if unknown), using linear and multiple regression analysis. METHODS: This prospective study included 10 profoundly hearing impaired children aged between 2 and 7 years with normal inner ear anatomy and no additional handicaps. They received the Advanced Bionics HiRes 90 K Implant with Harmony Speech processor and used HiRes-P with Fidelity 120 strategy. They underwent, impedance telemetry, neural response imaging, electrically evoked stapedial response telemetry (ESRT), and electrically evoked auditory brainstem response (EABR) tests at 1, 4, 8, and 12 months of implant use, in conjunction with behavioural mapping. Trends in electrophysiological and behavioural responses were analyzed using paired t-test. By Karl Pearson's correlation method, electrode-wise correlations were derived for neural response imaging (NRI) thresholds versus most comfortable level (M-levels) and offset based (apical, mid-array, and basal array) correlations for EABR and ESRT thresholds versus M-levels were calculated over time. These were used to derive predictive formulae by linear and multiple regression analysis. Such statistically predicted M-levels were compared with the behaviourally recorded M-levels among the cohort, using Cronbach's alpha reliability test method for confirming the efficacy of this method. RESULTS: NRI, ESRT, and EABR thresholds showed statistically significant positive correlations with behavioural M-levels, which improved with implant use over time. These correlations were used to derive predicted M-levels using regression analysis. On an average, predicted M-levels were found to be statistically reliable and they were a fair match to the actual behavioural M-levels. When applied in clinical practice, the predicted values were found to be useful for programming members of the study group. However, individuals showed considerable deviations in behavioural M-levels, above and below the electrophysiologically predicted values, due to various factors. While the current method appears helpful as a reference to predict initial maps in 'difficult to Map' subjects, it is recommended that behavioural measures are mandatory to further optimize the maps for these individuals. CONCLUSION: The study explores the trends, correlations and individual variabilities that occur between electrophysiological tests and behavioural responses, recorded over time among a cohort of cochlear implantees. The statistical method shown may be used as a guideline to predict optimal behavioural levels in difficult situations among future implantees, bearing in mind that optimal M-levels for individuals can vary from predicted values. In 'Difficult to MAP' scenarios, following a protocol of sequential behavioural programming, in conjunction with electrophysiological correlates will provide the best outcomes.

A rational approach to the management of obstructive sleep apnea syndrome.

Snoring & obstructive sleep apnea syndrome (OSAS) is a globally prevalent problem which is on the rise in recent times. The treatment modalities include medical appliances and surgery. It is mandatory to have a rational approach in the management of OSAS, by meticulously analyzing both anatomical and physiological parameters causing the disorder. To define a rational approach for the management of OSAS, by devising a comprehensive protocol with assessment of anatomical level of obstruction by dynamic MRI and physiological factors by Epworth sleepiness scale (ESS) and Polysomnography. A prospective study in 110 patients was conducted over a period of 2 years, at our institute. All patients in the study group were evaluated with dynamic MRI and ESS and Polysomnography. As per the management protocols defined in the study, surgery was advocated in 46 patients (Group 1) with severe compromise in airway, while another group of 64 patients (Group 2) were provided continuous positive airway pressure support (CPAP). Successful outcomes among these 110 patients were analyzed at the end of the study period. A few patients required multimodal therapy which included surgery and CPAP support. Among 46 patients, surgical treatment proved successful in 41 patients in whom AHI reduced from 46.96 to 12.88 (improved by 62%) and ESS improved by almost ten points. Among 64 patients in CPAP group, AHI reduced from 54.2 to 11.3 (improved by 79%) and ESS improved by 11 points in all the patients, but six of them had poor compliance. Five patients among the surgical group had persistence of symptoms. Inferences derived from the above results proved the success of formulating a rational approach in the management of OSAS. Critical analysis of the anatomical and physiological factors inducing obstructive episodes and an appropriate treatment plan is vital, to produce successful outcomes in patients with OSAS. Failure of surgical procedures, are often due to improper case selection. A small group of patients may require multimodal therapy with surgery and CPAP.

A Study of Complications and Morbidity Profile in Cochlear Implantation: The MERF Experience.

Cochlear implantation (CI) has been established worldwide as the surgical treatment for individuals with bilateral severe to profound hearing loss. This is a safe and standard procedure in the hands of experienced implant surgeons. Complications due to surgery are minimal and are often encountered in cases with congenital anomalies of the temporal bone and inner ear. Complications in CI are related to malfunctioning of the device or the process of wound healing. In most cochlear implant centers, as the surgeon's skill and clinical expertise in managing various cochlear implant cases improves with years of experience, the complication rates in his series ideally come down over time. Over the years, these well experienced clinics become tertiary referral centers for CI, receiving many difficult cases for implantation and hence such centers report data on complications, which become an important reference for many aspiring implant surgeons. Our study, performed in a premier CI centre in Chennai, looks at the various complications which were encountered in a case series of 300 implantees. Retrospective descriptive study with data collected from operative notes, patient questionnaires, auditory habilitation registers and medical records of cochlear implantees operated between, November 2006 to November 2010. A spectrum of major and minor complications, were categorized. Their incidence rates in relation to the demography of the patient profile and various events during surgical procedure were documented and analyzed. Appropriate management protocols were defined. Our management protocols have been highlighted and the relevant literature reviewed. This report of our experience with 300 cochlear implantees, reveals that complication rates at our center are in comparison with reputed centers worldwide. CI is very safe in the long term and provides optimal auditory awareness with speech perception and intelligibility for profoundly deaf individuals giving them an avid opportunity to integrate within the normal society.

Endolymphatic Sac Tumour: A Neoplastic Cause for Meniere's Syndrome.

Patients with intractable vertigo often present a diagnostic dilemma to the treating physician. A wide spectrum of diseases, ranging from those of the labyrinth onto the central nervous system, may present predominantly with vertigo. In some cases, it requires the clinical acumen of an experienced neuro-otologist, to decipher these vertiginous symptoms and arrive at a definitive diagnosis. Meniere's syndrome is one such phenomenon, where the endolymphatic hydrops may be attributable to varied aetiology. We report a case of sporadic (non-syndromic) Endolymphatic Sac Tumor which presented to us, mimicking a classical Meniere's syndrome. We discuss its clinical presentation, diagnostic modalities, operative technique and histo-pathological features. The case is reported along with a review of the world literature on this tumor, highlighting the diagnostic and management protocols advocated for this rare entity. Endolymphatic sac tumor is a rare entity which may masquerade as a classical case of Meniere's syndrome, wherein the triad of symptoms (as in endolymphatic hydrops) may not be alleviated by the usual treatment protocols. Tracing the aetiology of these symptoms, remains the most crucial factor in treating such patients.

Effect of intravenous administration of steroids in the management of sudden sensori-neural hearing loss: our experience.

The aim of this study was to investigate the efficacy and outcomes of intravenous high dose steroids in patients diagnosed with sudden sensori-neural hearing loss (SSNHL). The study also looked at the various co-morbidities influencing the outcomes of IV steroid therapy and also evaluated the improvement in associated symptoms like vertigo and tinnitus. This prospective study involved 30 patients treated during the 1 year period from January 2010 to 2011 in the Department of Otolaryngology, Madras ENT Research Foundation, Chennai. Male: female ratio was 1.3:1 and age range was 19-80 years. For all patients, pre treatment pure tone audiometry (PTA) was compared with post treatment PTA at 1 month. Treatment was given in the form of intravenous high dose methyl prednisolone. The patients were divided into two groups. Group 1 (20 pts) included SSNHL with no co-morbidity, group 2 (10 pts) included SSNHL with various co-morbidities. The mean hearing level improved from an average of 79.53 dB (HL) before treatment to 42.33 dB (HL) after treatment. In patients with predominantly low frequency HL (16 pts) PTA improved from 76.01 to 32.6 dB while in high frequency HL PTA improved from 83.55 to 53.43 dB. In our study of 30 patients, complete recovery occurred in 56.66% cases and marked improvement (>30 dB) in 16.66% patients. There was no improvement in 26.66% cases. Patients in group 2 had co-morbid factors like diabetes mellitus, dys-thyroidism and hypertension. A statistically significant improvement in the associated symptoms of tinnitus/vertigo, were also noted after IV steroid treatment. According to our results, emergency administration of high dose of Intra-venous corticosteroids to patients with SSNHL is highly recommended. Patients with high frequency preservation have better hearing improvement at the end of treatment. The critical time period for commencing IV treatment is less than 6 h from onset of hearing loss in order to restore normal hearing. High dose Intravenous steroids are a safe and effective treatment in sudden sensori-neural hearing loss.

Efficacy & outcomes of balloon sinuplasty in chronic rhinosinusitis: a prospective study.

Balloon Sinuplasty is a new technique which has revolutionized sinus surgery in recent times. Since its introduction in USA in 2004, it has become popular world-wide, due to its sophisticated technology, which uses balloon dilatational systems for dilating the sinus ostia through a minimally invasive approach and has provided satisfactory results in patients with chronic rhinosinusitis. Recent world literature supports the efficacy and outcomes of Balloon Sinuplasty system, with large multi-centric studies proving it to be a very effective tool in the management of various sinus pathologies. We performed this prospective clinical study to assess the efficacy & outcomes of Balloon Sinuplasty among 20 patients at our institution, who were followed up for 12 months after surgery. Patients were included as per inclusion criteria formulated for this study & were analyzed with respect to their pre-operative & post-operative symptomatology scores in comparison with their objective Diagnostic Nasal Endoscopy (DNE) & Computerized Tomography Scan of Paranasal Sinuses (CT-PNS) scoring systems. Significant improvements were recorded in patient's symptoms, from the first post-operative week until the end of the study period, and were objectively confirmed by the DNE & CT-PNS scores. The observations & results of our study highlight the efficacy of Balloon Sinuplasty technology in comparison to similar studies reported in recent world literature.

A clinical study of cortical auditory evoked potentials in cochlear implantees.

Normal maturation of central auditory pathways is a precondition for the optimal development of speech and language skills in children. The temporal cortex gets acoustically tagged due to auditory stimulation and important changes occur in the higher auditory centers due to hearing loss of any type and degree. Cochlear implantation increases auditory sensitivity by direct electrical activation of auditory nerve fibers, enabling phonemic awareness, discrimination and identification ultimately yielding speech understanding. Early implantation stimulates a brain that has not been re-organized and will therefore be more receptive to auditory input and greater auditory capacity. Cortical potentials have enabled us to objectively study this phenomenon. To assess the outcomes of Cochlear implants on the auditory cortex by analyzing cortical auditory evoked potentials (CAEPs) in the habilitation period. This prospective clinical study was performed in 30 pre-lingual candidates with varied etiology of deafness who underwent cochlear implantation at our institute over the last 1 year. The study group had two cohorts (group-1: 0-8 years and group-2: 8-15 years) which included candidates with normal inner ear and no syndromes or handicaps. All implantees in the study group underwent CAEP testing at 6 months and 1 year post-implantation and comparison of the CAEP wave parameters (P1 amplitude, P1 latency and P1 morphology) were done between the two cohorts. In children Implanted early (group-1) there was an early onset rapid increase in P1 amplitude along with a decrease in P1 latency during the follow-up period. Significant change in the CAEP wave morphology was also notable in group-1 unlike in group-2. Candidates who experienced less than 3 years of auditory deprivation before implantation showed P1 latencies, which fell into the range of normal children within 6 months of habilitation. Children with more than 6 years of auditory deprivation, however, generally did not develop normal P1 latencies or morphology even after 1 year of habilitation. The overall outcome with CAEP was much better in group-1 as compared to group-2 and the observations were is in comparison with the existing world literature. The advent of CAEP has objectively proved beyond doubt that there is a critical age for stimulating the auditory brain via cochlear implantation. There is considerable evidence for a developmental sensitive period, during which the auditory cortex is highly plastic. If sensory input is deprived to the auditory system during this sensitive period, then the central auditory system is susceptible to large scale reorganization. Restoring input to the auditory system by Cochlear Implant at an early age can provide the stimulation necessary to preserve the auditory pathways. However, if auditory input is not restored until after this developmental period, then the cross-modal reorganized pathways may exhibits abnormal functional characteristics as observed in recorded P1 amplitude, latencies and morphologies of CAEPs.

Magnet migration in a cochlear implantee - a serendipitous diagnosis.

The successful outcome of a cochlear implant habilitation program depends upon a multitude of vital factors, including the avid cooperation of the cochlear implantee, committed participation of the parents/family members and total dedication of the habilitation team of implant audiologists and auditory verbal therapists. In a rare situation, where the implantee's performance is suboptimal or poor inspite of successful implantation, anxious moments engulf the parents and the implant team, with the morbid fear of a device failure lingering at the back of their minds. We report such an incident in a 13-year-old cochlear implantee, who was an excellent cochlear implant performer for 8 years, following which she had rapid deterioration of her auditory verbal skills within the next few weeks. The hidden etiology, was the inconspicuous migration of the internal magnet of the Receiver-Stimulator Coil placed in the mastoid temporal bone of her skull, due to unexplained reasons. We share our experience with the diagnosis and management of this condition and review the existing world literature on this rarely reported entity.

Papillary carcinoma in a supra hyoid thyroglossal duct cyst - an unusual presentation.

Carcinomatous transformation of ectopic thyroid elements within the thyroglossal tract is a rare entity. We report a case of primary papillary carcinoma of thyroid presenting within the thyroglossal duct cyst in a 23 year old gentleman. The patient presented to us, as a case of suprahyoid thyroglossal cyst with sub-lingual involvement and he underwent surgical excision of the entire thyroglossal tract by Sistrunk's approach. The post-operative histopathological diagnosis was of a papillary carcinoma within the thyroglossal duct cyst. Hence, the patient was evaluated for a malignant focus in the thyroid which proved negative. He was counseled regarding the possibility of developing Carcinoma in the thyroid gland and offered two options of further management viz., total thyroidectomy followed by life long thyroid suppression or watchful observation and follow up. As the patient belonged to the low risk group, he opted for the second option. He is presently kept under meticulous follow up and remains asymptomatic till date. We present the pre- and post-operative imaging, intra-operative findings, histo-pathological features and review the present world literature on this rare entity.

Balloon sinuplasty - the first Indian experience.

The surgical management of sinusitis was revolutionized worldwide with the advent of the rigid Hopkins rod nasal endoscopes three decades ago. The traditional Messerklinger technique, was thus propagated worldwide by Prof. Stammberger, from the University of Graz in Austria and has come into vogue as functional endoscopic sinus surgery (FESS). The principal aim behind this procedure was the maximal preservation of the nasal mucosal integrity, while providing optimal disease clearance. Today, the introduction of a new technological innovation called 'balloon sinuplasty', has taken the field of sinus surgery a step further. This new technology is very similar to the principles of balloon angioplasty and today, this system has added an efficient, non-invasive tool in the armamentarium of the innovative endoscopic rhinologist. This FDA approved technique, in recent times has provided excellent results in various centers across the western world. We share our first surgical experience with the introduction of this cutting-edge technology in India.

Cochlear implantation in branchio-oto-renal syndrome - A surgical challenge.

Branchio-oto-renal syndrome (Melnick-Fraser Syndrome) is a rare Autosomal Dominant disorder characterized by the syndromic association of branchial cysts or fistulae along with external, middle & inner malformations and renal anomalies. Incomplete penetrance and variable expressivity are common with the phenotypic variation ranging from mild to severe forms & consisting of various eye, ear, oral and craniofacial abnormalities. Mutations in the EYA1 gene on chromosomal site 8q13.3 are identified as the primary cause of BOR syndrome. We present a 3year old child with BOR syndrome, who came to us with bilateral low set, malformed ears & profound cochlear hearing loss along with bilateral branchial fistulae & unilateral renal agenesis. This child underwent successful cochlear implantation recently. The clinical presentation, pre-operative investigations, intra-operative findings & post-op habilitation status are presented with special highlights on the unique facial nerve course along with middle and inner ear anomalies which posed a surgical challenge during cochlear implantation.

Alveolar soft part sarcoma of tongue base - A rare presentation of a rare tumor.

Alveolar soft part sarcoma is a rare, aggressive malignancy of uncertain histologic origin and enigmatic clinical behaviour. It has a characteristic histopathological picture, with a propensity for vascular invasion and distant metastasis. We report a case of alveolar soft part sarcoma involving the tongue base in an adolescent female. She underwent laser assisted excision of the tongue base tumour followed by post-operative radiotherapy. The clinical presentation, histopathological picture, immunohistochemical & cytogenetic studies, radio-imaging, management protocols and prognosis of this tumor have been discussed.

Clinical audit of outcomes in Cochlear Implantation an Indian experience.

This retrospective study is based on the assessment of outcomes of Cochlear Implantation taking into account various scoring systems like Category of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR). 100 candidates who were implanted between June 1997-June 2005 at Madras ENT Research Foundation (MERF), a tertiary referral center for cochlear implantation were included in the study. The results were analyzed using the above scoring systems to assess the performance levels of each implantee and to arrive at a cumulative result on the outcome of the implantation. Practical issues of concern to Cochlear Implantation in the Indian subcontinent were also analyzed.

Auditory brainstem implantation: The first Indian experience.

Multichannel auditory brainstem implants (ABI) are currently indicated for patients with neurofibromatosis type II (NF2) involving both vestibulocochlear nerves. The ABI helps bypass the damaged cochlear nerves and restores a level of auditory sensation via the electrical stimulation of the cochlear nucleus. The implant is usually placed in the lateral recess of the fourth ventricle at the time of tumor resection to stimulate the cochlear nucleus. We report a case of ABI done on a 15-year-old girl with bilateral vestibular schwannomas.

KTP-532 laser in the management of rhinosporidiosis.

Rhinosporidiosis, a difficult granulomatous disease of the nose is notorious for its high rate of recurrence and vascularity. Potassium Titanyl Phosphate (KTP) laserization of the mass seems to have provided an optimal solution in the management of this disease. We present our experience with the use of KTP-532 laser for this challenging disease.

Allergic fungal sinusitis- A clinico-pathological study.

The co-existence of fungal elements in allergic nasal Polyposis, has given rise to a distinct clinical entity known as 'Allergic fungal sinusitis ' (AF'S). Many a time, these fungal elements may not be diagnosed pre-operatively by routine diagnostic nasal endoscopy or CT scan of paranasal sinuses, due to the florid presentation of nasal polyps, which usually obscure the underlying fungal pathology. The diagnosis is often made intra-operatively. The post-operative confirmation of AFS is by histopathology, fungal smear, fungal culture, allergic murin study and fungal specific IgE titres. We report a series often such cases done in our institution, which highlight that AFS should be considered as a differential diagnosis in Sinonasal Polyposis cases, for their effective management.