Stapedial reflex decay in retrocochlear and cochlear lesions. Review of procedures and methods for conducting SRD tests.

The procedures for conducting and interpreting Stapedial Reflex Decay (SRD) are discussed. A modification of currently used procedures and interpretations in which testing is conducted at 750 and 1500 Hz as well as 500, 1000 and 2000 Hz is also discussed. Abnormal decay is defined as fatigue to half-life in less than 6.2 seconds. The SRD test patterns of 464 ears with cochlear lesions and 68 ears with retrocochlear lesions are presented and discussed. The findings are strongly supportive of SRD testing using the proposed procedures and interpretations.