The acoustic reflex in patients with asymptomatic multiple sclerosis.
A convenient, inexpensive test to identify multiple sclerosis during periods of symptomatic remission would be clinically advantageous. Recent studies have suggested that examination of acoustic reflex onset latency and rise time may be useful in detecting some forms of retrocochlear auditory pathology. This prospective, single-blinded study compares these features of the human acoustic reflex in a control sample, a sample with sensorineural hearing loss, and a sample with multiple sclerosis, to determine the usefulness of acoustic reflex measurements as a screening test for otherwise asymptomatic multiple sclerosis. Acoustic reflex threshold, onset latency, and rise time measurements were similar for all groups. This finding suggests that tests for abnormalities of acoustic reflex rise time and onset latency, under the conditions used in this study, may not be sufficiently sensitive to screen for the presence of otherwise asymptomatic multiple sclerosis.