[Duplex ultrasound of the penis. Value of a new diagnostic procedure based on over 1,000 patients].

In the period between December 1989 and December 1991, penile duplex sonography was performed, mostly after intracavernous injection of prostaglandin E1 in more than 1000 patients with erectile dysfunction or other penile disorders (Peyronie's disease, penile deviations, priapism). The most reliable evaluation criterion was the assessment of the peak flow velocity. Values of more than 25-30 cm/s with reference to the deep penile artery and more than 35-40 cm/s with reference to the dorsal artery indicated the integrity of the penile arteries. The assessment of the resistancy index has not proved to be a useful criterion because of its dependence on diastolic blood flow and therefore on the erection state, especially in cases of so-called cavernous insufficiency. Similar observations were made concerning the assessment of the increase in diameter of the deep penile arteries after intracavernous application of vasoactive drugs. Based on the fact that the increase in diameter is more dependent on the relaxation capacity of the cavernous smooth musculature and not on the actual blood flow, the measured values may be equal both in normal and in clearly disturbed blood circulation. In conclusion, duplex sonography is at present, together with color Doppler imaging, the most reliable vascular diagnostic tool and has clearly proved its superiority both to conventional penile Doppler imaging and penile angiography.