Study of cavernosal arterial anatomy using color and power Doppler sonography: Impact on hemodynamic parameter measurement

Purpose: We report on color and power Doppler ultrasound to study cavernosa l arterial anatomy, and evaluate the impact of vascular anatomy on the meas urement of hemodynamic parameters. Materials and Methods: Cavernosal arterial anatomy of 42 patients with erec tile dysfunction was evaluated using color and power Doppler ultrasound. A computerized waveform analysis was used to measure peak systolic velocity, end diastolic velocity and resistive indexes at various sites, including th e penile crura, and proximal mid and distal penile shaft. Hemodynamic param eters were measured in each artery in cases of bifurcated or multiple caver nosal arteries. Results: A total of 80 corpora were adequately evaluated. We observed a sin gle artery without major proximal branches in 37 corpora, a single artery w ith major proximal branches in 17, bifurcated arteries in 15, 2 cavernosal arteries in 4 and marked arterial tortuosity in 1. In 6 corpora the main ca vernosal artery arose from the superficial dorsal artery. The peak systolic velocity was highest at the proximal and decreased progressively at the di stal site. The peak systolic velocity plus or minus standard deviation at t he mid shaft averaged 69.3 +/- 30.0% of that at the proximal penile shaft. Of the 15 corpora with bifurcated arteries 67% had a 40% or greater differe nce in peak systolic velocity between the branches. Complete or partial occ lusion of the cavernosal artery was identified in 3 corpora, and a dramatic difference in peak systolic velocity proximal and distal to the stenotic a rea was demonstrated. Conclusions: Cavernosal arterial anatomy is variable and hemodynamic parame ters differ at various sites of measurement. Parameters should be measured at a consistent proximal site to obtain a reliable assessment. Variations i n vascular anatomy and cavernosal artery pathology should be considered whe n interpreting color Doppler sonography and before penile vascular surgery.