[Deep pudendal reflex]

32 healthy women ranging from 20 to 68 years (51.84 +/- 10.36) were tested for Deep Pudendal Reflex (DPR). Dantec 13L40 (St. Mark's) superficial electrodes were used to pick up the responses of the external anal sphincter. These devices consist of a bipolar stimulating electrode mounted on the tip of the gloved index finger which is inserted into the rectum; 3 cm proximally at the base of the finger are recording electrodes which pick up the contraction response of the anal sphincter. To obtain the DPR the ischial spine is localized on transrectal examination and electrical stimuli given at that side, applying square stimulus of 0.2 ms duration and 0.5 Hz frequency. This stimulates the pudendal nerve as it leaves the pelvis through the greater sciatic notch, before it branches into the inferior rectal (to the anal sphincter) and perineal nerve (to the periurethral striated muscle). The conduction time was measured as the latency from the time of stimulation of the starting point of the reflex response curves. The shortest latency of various responses was accepted and measured in milliseconds (ms). The amplitudes of the responses were measured in microvolts (uv). We obtained reproducible DPR in all subjects. Mean latency was 36.18 +/- 4.29 ms; mean amplitude was 337.50 +/- 218.49 uv (Fig. 1, Table 2). DPR is a pudendal-anal reflex like the bulbo-cavernous reflex, but differs in latency, stimulation localization and afferent limb although both follow a common final afferent pathway.