Peak systolic velocities may be falsely low in young patients with erectile dysfunction

Introduction of duplex ultrasonography with color flow Doppler analysis after intracavernous injection of vasoactive drugs has been reported to be a minimally invasive and accurate method, and considered the gold-standard technique for evaluating penile hemodynamics. However, several studies have demonstrated that in some cases Color Doppler Ultrasound (CDU) testing may result in wrong diagnosis because of anxiety and increased sympathetic stimulation.

This study was carried out to evaluate the impact of age on the decision to repeat CDU in patients with initial low peak systolic velocities (PSVs).

This is a prospective study involving 71 patients with erectile dysfunction (ED) who presented to the Department of Andrology, Sexology and Sexually Transmitted Diseases at Cairo University between December 2000 and April 2002. An intracavernous pharmacotest and CDU with prostaglandin E1, papaverine, and phentolamine was performed. All patients in the study had poor response to intracavernous pharmacotesting and achieved a low PSV (<30 cm/second) during the initial CDU examination. The CDU was repeated 2 weeks later. The 71 patients were grouped into four according to age: group A (20-29 years old) consisted of 11 patients, group B (30-39 years old) consisted of 19 patients, group C (40-49 years old) consisted of 20 patients, and group D (50-59 years old) consisted of 21 patients.

The group A patients experienced a statistically significant increase (P < 0.05) in their PSV measurements, which reached normal values in the second CDU. None of the patients of groups B, C, or D experienced any statistically significant change (P > 0.05) in their PSV measurements in the second CDU, which remained below normal values. Also, there was a statistically significant difference between the PSV measurements of group A and the other three groups.

Low PSV measurements in young men (less than 30 years old) with ED should be interpreted with caution. The effect of sympathetic overtone because of the environment in the office and anxiety related to penile injection, together with any underlying psychological disturbance, should be taken into consideration during the evaluation of the results of the CDU. Repetition of the CDU is recommended before considering any additional invasive diagnostic or therapeutic modalities.