Is Sildenafil Citrate an Alternative Agent in the Evaluation of Penile Vascular System with Color Doppler Ultrasound?

Abstract

Introduction: The ideal diagnosis and therapeutic agent for erectile dysfunction (ED) would be an oral drug taken prior to color Doppler ultrasound (CDU) examination and sexual intercourse. In the present study we have investigated if the efficacy of oral sildenafil is optimal in the diagnosis of underlying pathology of ED. Material and Methods: The study group comprised of 41 patients with ED. Firstly, all patients underwent CDU examinations after the combined intracavernosal injection of 60 mg of papaverine and sexual stimulation (CIS). Secondly, these patients were examined after taking 50 mg of oral sildenafil citrate combined with self-manual and visual sexual stimulation. Results: The differences of peak systolic velocity values were statistically significant between CIS and sildenafil (right: 40.7 ± 2.9 vs. 28.7 ± 3.3; left: 41.2 ± 3.3 vs. 25.7 ± 2.4; p < 0.001) in patients with normal penile vascular system. However, end-diastolic velocity and resistance index values were not significant between the same groups. In addition, there were not significant differences for peak systolic and end-diastolic blood flow velocities and resistances index with CIS and sildenafil in cases with vasculogenic ED. Conclusions: Sildenafil citrate plus visual sexual stimulation is not reliable as CIS to make accurate interpretation of penile vascular status using CDU. On the other hand, in some cases suspected of psychogenic ED after detailed sexual history, sildenafil might be tried as an initial step of the functional evaluation with CDU in order to prevent prolonged erection risk with intracavernosal injection of vasoactive agents.