Stapedius reflex in multiple sclerosis.

An analysis was carried out of recordings of the crossed stapedial reflex response in a series of normal subjects and 30 patients with multiple sclerosis. Parameters measured included latency, contraction time, amplitude, and relaxation time. Criteria derived from the normal group and applied to the multiple sclerosis group showed clear evidence of abnormality in 10 patients. This can be attributed to lesions in the pathways of the second and third order neurones in the trapezoid body and superior olivary complex. Present evidence suggests that further refinements in the measurement technique might significantly increase the detection rate of abnormalities in multiple sclerosis.