Sildenafil citrate for penile hemodynamic determination: an alternative to intracavernosal agents in Doppler ultrasound evaluation of erectile dysfunction

Abstract Objectives. To suggest a new noninvasive method for penile Doppler ultrasound (PDU) evaluation of erectile dysfunction using oral sildenafil citrate as an erection induction agent. Methods. A total of 20 patients admitted with the complaint of erectile dysfunction were evaluated by the short form of the International Index of Erectile Function. A total score of less than 25 was accepted as erectile dysfunction and PDU was performed. The initial penile study consisted of PDU examination under visual sexual stimulation (VSS), and the peak systolic velocity, end-diastolic velocity, and resistance index were recorded. Measurements of all the parameters were repeated on the same patients after intracavernosal papaverine, intracavernosal prostaglandin E 1 (PGE 1 ), and oral sildenafil citrate administration, plus VSS. All patients had these four tests in the same order at weekly intervals. Sildenafil citrate was given orally 45 minutes before Doppler investigation, and patients had VSS during the waiting period. The patients were asked about their satisfaction and comfort after each test. Statistical analysis was performed using the Wilcoxon and Mann-Whitney U tests. Results. The measurements with papaverine, PGE 1 , and sildenafil citrate were significantly different from those after only VSS ( P 1 , and sildenafil citrate results were not different from each other according to the peak systolic velocity, end-diastolic velocity, and resistance index measurements ( P >0.008). Patients commented that although PGE 1 was the strongest erectogenic agent, sildenafil citrate was the most convenient. Conclusions. Since the results of PDU with oral sildenafil citrate in association with VSS were not statistically different, we suggest a new noninvasive erection induction method for the purpose of PDU evaluation of erectile dysfunction.