Penile and perianal pudendal nerve somatosensory evoked potentials in the diagnosis of erectile dysfunction

Abstract

Neurophysiologic examinations in differential diagnosis of erectile dysfunction comprise electromyogramme of the pelvic¯oor, pudendal nerve terminal motor latency (PNTML) and evaluation of pudendal somatosensory evoked potentials (SSEP). We focused our interest on comparing diagnostic importance of penile and perianal pudendal nerve SSEP.We examined 20 patients suffering from erectile dysfunction and 20 patients without any manifestation of impotence. The stimulus was administered using penile ring electrodes at the base of the penis (cathode) and distally on the penis shaft (anode), as well as a perianal surface electrode applied at 3 o'clock in lithotomy position and 5 cm laterally on the gluteal skin. The potentials were recorded with intradermal needle electrodes at C z ±2 cm (different) and F z (indifferent). 500 stimuli were averaged for a single tracing. The stimulus strength was set at an average of 3±4 times the stimulus threshold.Cortical latency of P 40 ranged from 39.0 to 45.6 ms (penile) and from 33.6 to 43.2 ms (perianal) in the control group, in the patient group latencies ranged from 38.8 to 51.6 (penile) and 34.0 to 44.8 ms (perianal). In two patients no potential was recordable after perianal stimulation, one patient showed a marked prolongation of the penile response with a normal perianal latency. Penile and perianal latencies of P 40 were signi®cantly prolongued in the patient group compared to the control group (P`0.05).The combination of penile and perianal pudendal SSEP may provide valuable additional information in differential diagnosis of erectile dysfunction, especially allowing to identify different sites of neurogenic lesions. In contrast to perianal pudendal SSEP, penile stimulation may help to discover pathologic changes in the distal course of the pudendal nerve, especially the dorsal nerve of the penis.

Small fibre pathology is associated with erectile dysfunction in men with type 2 diabetes

“…13,39 Penile vasotactile and thermal thresholds assessing somatic small fibre neuropathy have been found to be abnormal in diabetic patients with ED. [40][41][42] More sophisticated tests including penile somatosensory evoked potentials 43 and corpus cavernosum electromyography 44 are abnormal in ED but are not routinely available.…”

Chronic prostatitis: differential diagnosis. Case report discussion

“…Важным методом исследования пациентов с пудендальной невропатией или невралгией является электронейромиография полового нерва с оценкой его терминальной моторной латентности [11]. Использование самоклеящихся одноразовых электродов, легко устанавливаемых пальцем в перчатке, позволяет широко применять этот метод в клинической практике.…”

Somatosensible Potenziale bei anorektalen Störungen

“…Unbestritten ist, dass es zwischen den Pudendus-SSEP und den analen SSEP erhebliche Latenzdifferenzen gibt [3,4], da die Strecke der in der Gesamtlatenz berück-sichtigten peripheren Nerven different ist. Wäre es nur die Strecke der untersuchten Nerven, müsste eine enge Korrelation zwischen den beiden Untersuchungen bestehen, was nicht der Fall ist (Korrelationskoeffizient 0,570 bzw.…”

“…Bei Erektionsstörungen haben sich in der Differenzialdiagnostik die Pudendus-SSEP etabliert, wobei die diagnostische Aussage begrenzt ist [4], bei analen Funktionsstörungen bleibt die Aussagekraft der Pudendus-SSEP unklar.…”