Dissociation between caloric test and the video head impulse test in individuals with auditory neuropathy spectrum disorders

The present study aimed to measure an association between the caloric test and vestibulo-ocular reflex gain and refixation saccades in individuals with auditory neuropathy spectrum disorders. Twenty individuals (9 males and 11 females), in the age range of 17 to 38 years, diagnosed with auditory neuropathy spectrum disorders, and 20 normal-hearing individuals (age and gender matched) participated in the study. All the individuals underwent case history, pure tone audiometry, immittance evaluation, otoacoustic emissions, auditory brainstem response, caloric tests and video head impulse tests. All the patients with auditory neuropathy spectrum disorders in the present study had hypoactive caloric responses, which suggested peripheral vestibular lesions. The mean vestibulo-ocular reflex gain was reduced in few patients with auditory neuropathy, whereas few patients had normal vestibulo-ocular reflex gain. The present study revealed a discrepancy between the caloric and video head impulse test results in auditory neuropathy spectrum disorders. The vestibular evaluation should be done for all patients with auditory neuropathy spectrum disorders to understand the various types of vestibular nerve lesions.