Recently, it was reported that
phentolamine redosing during penile duplex can abolish a false diagnosis of venous leakage in patients with
impotence. The aim of this study is to identify any useful role of
phentolamine redosing in diagnosis of
venogenic impotence. Sixty-seven consecutive patients complaining of weak erection for at least 6 months were included in this study. Penile color Doppler ultrasound (CDU) was performed using a 7.5 MHz linear array transducer with a color flow mapping capability. Following intracavernous injection of 20 microg
prostaglandin E1 (
PGE1), all patients with persistent end diastolic velocity (EDV) >5 cm/sec with an erectile response of E3 or lower, 20 min after intracavernosal injection of
PGE1, were asked to revisit our clinic for a second CDU, 2 weeks later. During initial CDU examination, all 67 patients experienced poor response to 20 microg
PGE1 with their average peak systolic velocity (PSV) and EDV being 42.8 and 6.6 cm/sec, respectively. The second CDU examination had similar results to the first one. Addition of 2 mg
phentolamine did not significantly change the PSV and EDV of cavernosal arteries in any of the 67 patients. In conclusion, addition of intracavernous
phentolamine during
PGE1 CDU examination carries no advantage over the use of
PGE1 alone regarding cavernosal artery response in patients with suspected venogenic EDV.