Intracavernous injection of prostaglandin E1: the application to cavernosography and penile blood flow measurement for the diagnosis of venogenic impotence.

We injected 20 micrograms of prostaglandin E1 (PGE1) intracavernously in 32 patients with impotence, we then examined penile blood flow using a Xe-133 washout technique. In addition, we also performed a cavernosography. After PGE1 injection, 18 patients (56%) showed complete erection, 10 (31%) tumescence, and 4 (13%) no response. Fourteen patients who presented either an inadequate or no response to PGE1 injection were suspected to have vasculogenic impotence. Cavernosography of patients who showed good response after PGE1 injection demonstrated no obvious venous leakage. In this group penile blood flow decreased after full erection. However, 7 patients (50%) suspected to have vascular problems showed venous leakage. Subsequently, these 7 patients appeared to be cases of venous incompetence. The penile blood flow of these 7 patients before or after PGE1 injection was not statistically different from that of other groups. Based on these findings, cavernosography after PGE1 injection appears to be useful for differentiating the venous factor of impotence.