Auditory Brainstem Response in Duane's Retraction Syndrome

Abstract

Auditory Brainstem Response (ABR) is a measure of electrical events occuring along the auditory pathway. Seven distinct waves have been identified, the latencies of which are used to localize brainstem lesions. In response to the finding that some Duane's Syndrome patients exhibit abnormal Wave III latencies (indicating a pontine anomaly), we have performed ABR on 15 subjects with Duane's Syndrome in hopes of correlating abnormal Wave III latencies with the type of Duane's Syndrome. Lee's screen and electro-oculography as well as clinical signs were used to identify the three types of Duane's Syndrome. Of the 30 ears tested, 100% of the male and 81% of the female ears demonstrated Wave III latencies within two standard deviations of their respective normal values and were, therefore, considered normal. The remaining 19% of female Wave III latencies were moderately late. These 3 ears also demonstrated hearing loss with conductive components and, therefore, the increased latencies could not be attributed to the Duane's Syndrome specifically. We could not correlate Wave III abnormality with a specific type of Duane's Syndrome. Possible reasons for this discrepancy are discussed with a suggestion that further research is necessary.

• Duane's Syndrome
• auditory brainstem response
• saccadic velocities