Role of Cervical Vestibular Evoked Myogenic Potentials (cVEMP) as Outcome-Measure of Glycerol Test.

Diagnosis of Meniere's disease is mainly clinical although many tests have been studied for efficacy in diagnosis of Meniere's disease. Glycerol test is a functional test to identify hydrops in Meniere's disease and can be done with PTA, Speech audiometry, otoacoustic emission, EcochG and cVEMP as its outcome measures. The study aimed to compare two outcome measures of glycerol test to identify Meniere's disease; to determine whether the stage of Meniere's disease affected glycerol outcomes; and to attempt to identify independent variables that could predict outcomes of glycerol test. 26 ears of 20 Meniere's disease participants were evaluated using PTA-based and cVEMP-based glycerol tests. Each test identified ten of 26 ears with Meniere's disease; and high agreement was noted in the two outcome measures. The stage of Meniere's disease based on four frequency hearing threshold average was not associated with outcome of glycerol test, but staging of Meniere's disease based on symptom duration was associated with glycerol test results. As the duration of symptoms increased there was lesser chance of positive outcomes on glycerol test; but intermediate stages of Meniere's disease showed positive outcomes. Variables such as age, gender, severity of hearing loss, duration of symptoms and pre-glycerol cVEMP measurements could not predict glycerol test outcomes. PTA-based and cVEMP- based glycerol tests hold promise in the test battery for identification of Meniere's disease. Positive findings on the test lead to confirmatory diagnosis but a negative glycerol test does not rule out Meniere's disease.

Role of cervical vestibular evoked myogenic potentials (cVEMP) and auditory brainstem response (ABR) in the evaluation of vestibular schwannoma / Papel dos potenciais evocados miogênicos vestibulares cervicais (cVEMP) e potencial evocado auditivo de tronco encefálico (PEATE) na avaliação do schwannoma vestibular

Abstract Introduction: Cervical vestibular evoked myogenic potentials (cVEMP) can assess the integrity of the inferior vestibular nerve thereby promising to be a useful tool in the audiological test battery to diagnose vestibular schwannoma. Objective: To ascertain the utility of cVEMP in diagnosis of vestibular schwannoma in conjunction with the ABR and to evaluate whether the size of lesion has any effect on the cVEMP measures. Methods: Case-files of 15 known cases of vestibular schwannoma whose pure tone audiometry, auditory brainstem response (ABR), cVEMP and radiological investigation findings were available, were included in the study. Patients were categorised as large or small tumours based on the size. The absolute and inter-peak latencies of ABR, amplitudes of waves V and I, and inter-aural latency difference of wave V of ABR; and latency of P1 and N1 of cVEMP and amplitude of P1-N1 complex were considered in the study. Results: There were eight large and nine small tumours. All the patients with large tumours showed significant severity of hearing loss whereas only three out of nine patients with small tumours showed severe to profound deafness in the affected ear. The rest showed hearing status ranging from normal hearing sensitivity to moderate hearing loss. Most of the patients with large tumours showed complete absence of ABR in the affected ears with no identifiable wave-peaks. ABR in small tumours exhibited delayed III-I and delayed V-I interpeak latency interval (IPL). Four out of five patients with large unilateral tumours revealed contralateral effects of reduced amplitude or absence of cVEMP. On the contrary, six out of eight unilateral small tumours showed a normal cVEMP response in the contralateral ear. Both the patients with NF2 in the present study demonstrated cVEMP abnormalities. Conclusion: ABR and cVEMP, when used in combination, can be of immense use in identification of neuro-otologic conditions such as vestibular schwannoma and bilateral tumours in NF2. In the evaluation of unilateral vestibular schwannoma, abnormal contralateral findings of cVEMP and ABR are strongly indicative of the tumour size >2.5 cm. In unilateral severe to profound loss wherein ABR in poorer ear cannot give information of site-of-lesion, cVEMP can help in the differentiation.

Resumo Introdução: Os potenciais evocados miogênicos vestibulares cervicais (cVEMP) podem avaliar a integridade do nervo vestibular inferior, prometem assim ser uma ferramenta útil na bateria de testes audiológicos para o diagnóstico de schwannoma vestibular. Objetivo: Determinar a utilidade de cVEMP no diagnóstico de schwannoma vestibular em conjunto com PEATE e avaliar se o tamanho da lesão tem qualquer efeito sobre as medidas do cVEMP. Método: Quinze casos diagnosticados com schwannoma vestibular cujos exames de audiometria tonal pura, potencial evocado auditivo de tronco encefálico (PEATE), cVEMP e investigação radiológica estavam disponíveis foram incluídos no estudo. Os pacientes foram classificados como portadores de tumores grandes ou pequenos. As latências absolutas e interpico de PEATE as amplitudes das ondas V e I e a diferença de latência interaural da onda V da PEATE e a latência de P1 e N1 de cVEMP e amplitude do complexo P1-N1 foram consideradas no estudo. Resultados: Havia oito tumores grandes e nove pequenos. Todos os pacientes com tumores grandes apresentavam perda auditiva grave enquanto apenas três dos nove pacientes com pequenos tumores apresentaram surdez grave a profunda na orelha acometida. O restante apresentou audição que variou de normal a perda auditiva moderada. A maioria dos pacientes com tumores grandes demonstrou ausência completa de PEATE nas orelhas acometidas sem picos de onda identificáveis. O PEATE em tumores pequenos apresentou intervalo de latência interpico (ILI) tardia III-I e tardia V-I. Quatro em cada cinco pacientes com tumores grandes unilaterais revelaram efeitos contralaterais de amplitude reduzida ou ausência de cVEMP. Ao contrário, seis dos oito tumores pequenos unilaterais apresentaram resposta de cVEMP normal na orelha contralateral. Ambos os pacientes com NF2 no presente estudo demonstraram anormalidades na cVEMP. Conclusão: PEATE e cVEMP, quando usadas em combinação, podem ser úteis na identificação de condições neuro-otológicas como schwannoma vestibular e tumores bilaterais em NF2. Na avaliação de schwannoma vestibular unilateral, achados contralaterais anormais de cVEMP e PEATE são fortemente indicativos de tumor >2,5 cm. Na perda unilateral grave a profunda, na qual o PEATE na orelha mais prejudicada não fornece informações do local da lesão, cVEMP pode ajudar na diferenciação.

Auditory System Synchronization and Cochlear Function in Patients with Normal Hearing With Tinnitus: Comparison of Multiple Feature with Longer Duration and Single Feature with Shorter Duration Tinnitus.

OBJECTIVE: To observe cochlear and brainstem function in normal hearing ears with tinnitus using DPOAE and ABR audiometry. DESIGN: Case-control study. SAMPLE SIZE: Included 60 normal hearing male patients with age less than 45 years; control group consisted of 30 patients without tinnitus and the study group consisted of those with unilateral tinnitus of at least 6 month duration. Pure tone audiometry, tinnitus matching (pitch & loudness), DPOAE (SNR & Amplitude) and ABR results of absolute latency of wave I, III and V, with IPL difference of I-III, III-V & I-V, and ILD-V were investigated. RESULTS: SNR and amplitude value of DPOAE were significantly different between tinnitus ears and without tinnitus ears. Abnormal prolonged absolute latencies of peak I, III, V suggesting presence of hearing loss above 8 kHz and significant difference of only IPL III-V in the tinnitus ear suggesting of upper brain steam lesion in tinnitus patients were found. The IPL of III-V and ILD-V findings were significantly different in longer duration with multiple features (more than one type of pitch) than shorter duration with single feature tinnitus. Thus whole brainstem function has significant relationship with the presence of tinnitus, longer duration with multiple nature of tinnitus perception. CONCLUSION: Abnormal OAE and ABR results were present in patients with tinnitus. It was more prominent in patients with longer duration with multiple features of tinnitus perception.

Treatment of Tinnitus: A Scoping Review.

BACKGROUND: Tinnitus is a perception of an auditory sensation without the presence of an external sound. It has devastating impact on the quality of life and psychosocial aspect of the sufferer. Mechanisms of tinnitus not clear; however, its management include counselling, hearing aids, tinnitus masking, relaxation therapy, cognitive behaviour therapy and tinnitus retraining therapy. OBJECTIVE: To conduct a scoping review to explore the role of counselling, hearing aids, tinnitus masking, relaxation therapy, cognitive-behavioural therapy and tinnitus retraining therapy in India. To also provide an overview of efficacy of these approaches in tinnitus management. RESEARCH DESIGN: Scoping review. STUDY SAMPLE: Experimental studies, follow-up assessments, and reviews assessing tinnitus treatment approaches were identified as a result of an electronic database met search. RESULTS: The evidence suggests that all tinnitus management programs have their unique benefits in the treatment of tinnitus. Given the confounding variables that include length of therapy, tinnitus severity and subject population, the overall level of evidence is equivocal. Nonetheless, the efficacy of CBT appears reasonably established and combined approach (masking + counselling + attention diversion) appears to be most promising for audiologists for future tinnitus management. A common ground of therapeutic elements was established and evidence was found to be robust enough to guide clinical practice. CONCLUSION: The use of more robust methodology with well-defined control groups, as well as randomization of clinical trials in future studies would increase the quality of evidence in the study of tinnitus management. CLINICAL RECOMMENDATION: Combined therapies (masking + counselling + attention diversion) appear more appropriate in the treatment of tinnitus as the evidence is not sufficient to support a specific treatment method.

Role of cervical vestibular evoked myogenic potentials (cVEMP) and auditory brainstem response (ABR) in the evaluation of vestibular schwannoma.

INTRODUCTION: Cervical vestibular evoked myogenic potentials (cVEMP) can assess the integrity of the inferior vestibular nerve thereby promising to be a useful tool in the audiological test battery to diagnose vestibular schwannoma. OBJECTIVE: To ascertain the utility of cVEMP in diagnosis of vestibular schwannoma in conjunction with the ABR and to evaluate whether the size of lesion has any effect on the cVEMP measures. METHODS: Case-files of 15 known cases of vestibular schwannoma whose pure tone audiometry, auditory brainstem response (ABR), cVEMP and radiological investigation findings were available, were included in the study. Patients were categorised as large or small tumours based on the size. The absolute and inter-peak latencies of ABR, amplitudes of waves V and I, and inter-aural latency difference of wave V of ABR; and latency of P1 and N1 of cVEMP and amplitude of P1-N1 complex were considered in the study. RESULTS: There were eight large and nine small tumours. All the patients with large tumours showed significant severity of hearing loss whereas only three out of nine patients with small tumours showed severe to profound deafness in the affected ear. The rest showed hearing status ranging from normal hearing sensitivity to moderate hearing loss. Most of the patients with large tumours showed complete absence of ABR in the affected ears with no identifiable wave-peaks. ABR in small tumours exhibited delayed III-I and delayed V-I interpeak latency interval (IPL). Four out of five patients with large unilateral tumours revealed contralateral effects of reduced amplitude or absence of cVEMP. On the contrary, six out of eight unilateral small tumours showed a normal cVEMP response in the contralateral ear. Both the patients with NF2 in the present study demonstrated cVEMP abnormalities. CONCLUSION: ABR and cVEMP, when used in combination, can be of immense use in identification of neuro-otologic conditions such as vestibular schwannoma and bilateral tumours in NF2. In the evaluation of unilateral vestibular schwannoma, abnormal contralateral findings of cVEMP and ABR are strongly indicative of the tumour size >2.5cm. In unilateral severe to profound loss wherein ABR in poorer ear cannot give information of site-of-lesion, cVEMP can help in the differentiation.

Swallowing characteristics in Amyotrophic Lateral Sclerosis.

BACKGROUND: Motor neurone disease also commonly known as Amyotrophic Lateral Sclerosis (ALS) is a neurological condition which affects various motor functions of the body. Dysphagia (disordered swallowing) is commonly seen in patients with ALS having bulbar symptoms. OBJECTIVES: Research reveals presence of dysphagia in patients with ALS at various stages of swallowing using instrumental assessment. However, very few studies have been done focussing on clinical profiling of swallowing in these patients. Hence, a need was felt to profile the specific characteristics. METHODOLOGY: Five patients diagnosed with ALS were assessed for presence of swallowing disorder using a swallowing checklist which focussed on assessing each stage of swallowing. RESULTS: Results revealed that patients with ALS exhibit difficulties in oral preparatory, oral and pharyngeal stages of swallowing. Inability to hold bolus, reduced mastication, residue in the oral cavity and nasal regurgitation while swallow were observed due to the affected oromotor functions. Swallow reflex was delayed in all the patients. Cough before and during swallow was also observed. CONCLUSION: Dysphagia is a common symptom in patients with ALS and occurs due to the affected oromotor functions. Specific information of the stages of swallowing helps in planning treatment in clinical practice.

Adam Politzer-Father of Modern Otology.

Adam Politzer (1835-1920) was born in Alberti near the city of Budapest in Hungary. He studied medicine at the University of Vienna and obtained his Doctorate degree in 1859. Some of his teachers belonged to the famous second "Vienna School" such as Joseph Skoda, Karl Rokitansky, Von Hebra, Josef Hyrtil, Johann Von Oppolzer and famous physiologist Carl Ludwig -who took special interest in him and was influential in his subsequent career. Politzer showed unusual interest in diseases of the ear and started to work in Carl Ludwig's laboratory. His interest at that time was mainly the physics of the auditory system. He studied the innervations of the intrinsic muscles of the ear There he was the first to demonstrate that the innervations of the tensor tympani muscle was by trigeminal nerve and that of the stapedial muscle was by facial nerve. He studied the air movement in the Eustachian tube and variation of air pressure in the tympanic cavity by connecting two manometers- one placed in the external auditory canal meatus, and another in the pharynx. He showed valve near the opening into the middle ear which controls the process. It is usually closed to keep the bacteria and other things away from the mouth and nose.

Occurrence of communication and swallowing problems in neurological disorders: analysis of forty patients.

BACKGROUND: Communication and swallowing problems are common as a result of neurological conditions like stroke, traumatic brain injury, neoplasms of the nervous systems, viral encephalitis, diseases affecting neuromuscular junction and neuro degenerative conditions. The most frequently encountered problems are dysarthria, aphasia, dysphagia and apraxia of speech. OBJECTIVES: Although these disorders are mentioned in literature, very few studies describing the occurrence in different neurological conditions are available in Indian context. Hence, a need was felt to carry out such a study. METHODOLOGY: A heterogenous group of forty patients with neurological conditions were assessed for presence of speech, language and swallowing problems. A percent analysis was carried out to determine the occurrence of aphasia, dysarthria and dysphagia in general, in specific diseases and also to describe type of aphasia and dysarthria according to the characteristics presented. RESULTS: It was seen that the most frequently occurring disorder was dysarthria (60%), followed by dysphagia (55%) and aphasia (18%). It was also noted that dysarthria and dysphagia co-existed in around 45% patients with neurological diseases. CONCLUSIONS: It can be concluded that speech, language and swallowing problems are frequent in individuals with neurological conditions. Speech language pathologist plays an important role as a member of the rehabilitation team in a neurological setup with respect to identifying these problems and initiating intervention at the earliest. Hence, it is necessary for speech language pathologist to be well versed with the features each disorder may present with in terms of communication and swallowing.

Audiometric profile in patients with chronic renal failure.

OBJECTIVES: To determine the occurrence of hearing loss and to establish audiometric profiles and patterns of hearing impairment in patients with chronic renal failure (CRF). METHODS: A retrospective study examined the relationship between the different stages of CRF and corresponding audiologic findings in those patients. Twenty-three subjects (46 ears) in the age range of 25 to 60 years were included in the study. These subjects were arranged into groups ranging from the second to fifth stages of CRF. Audiologic assessment in each subject was performed using a battery of tests, which included pure-tone audiometry, transient otoacoustic emission (TOAE), distortion product otoacoustic emission, and brainstem evoked response audiometry (BERA). RESULTS: Significant differences in the degree of hearing loss were observed among patients with different stages of CRF. It was noted that almost all (95.65%) patients with CRF did not pass the TOAEs. It was important to notice that none of the patients with CRF showed findings on BERA that pointed to retrocochlear involvement. Thus, the present study found that most patients (65.21%) had a cochlear pathology. CONCLUSIONS: We observed that (a) there is a high incidence of hearing loss among patients with CRF; (b) the methods of treatment (hemodialysis and conservative treatment) may not influence the impact of the disease on hearing; (c) levels of serum electrolytes and biochemical constituents of blood do not seem to correctly reflect the audiologic status of a CRF patient; and (d) hearing loss in patients with CRF has a distinct audiologic pattern. Given that CRF involves hearing loss, routine audiologic assessment in patients with this condition is essential.