In the evaluation of patients for sexual dysfunction, several laboratory methods are being used among which pudendal SEP and Bulbocavernosus reflex study are recently popular. Electrodiagnostic evaluation were performed on 37 healthy males and 111 patients with sexual dysfunction. Following results were obtained.

1) Short latency P₁ SEP stimulating pundendal nerve in healthy males was 38.2±2.2 msec, and the average bulbocavernosus reflex latencies were 32.4±3.6 on the right, 32.5±3.5 msec on the left.

2) Patients showing great abnormality in pudendal SEP were spinal cord injury patients of UMN type and the average P₁ latency was 46.3±7.1 msec which revealed significant difference from the standard value.

Patients group showing one of the most prolonged bulbocavernosus reflex latency was spinal cord injury patients of LMN type with the average value of 48.4±14.6 msec on the right, and 51.8±16.2 msec on the left which also shows significant difference from the standard value.

3) There were no significant difference between normal group and psychogenic, vasculogenic and low back pain patients both in pudendal SEP and bulbocavernosus reflex study. However, significant difference was obtained in the patients of diabetes mellitus, pelvic trauma and spinal cord injury patients of UMN type in the study of pudendal SEP, and there was also a significant difference in the patients with pelvic trauma and spinal cord injury of LMN type in bulbocavernosus reflex study.

4) Electrodiagnostic abnormality rate of the patient group with organic lesion, excluding psychologic group, were 30.6% by pudendal SEP and 21% by bulbocavernosus reflex study. When pudendal sEP study and bulbocavernosus reflex study were done together, 40.3% of abnormality were detected.