Evaluation and therapeutic regulation of erectile dysfunction with visual stimulation test. An objective approach by...

An objective evaluation of the psychogenic cause of erectile dysfunction by performing the visual stimulation tumescence and rigidity (VSTR) test and sildenafil citrate test, together with the effectiveness of sildenafil citrate medication on impotence caused by different etiologies.

Between 1998 and 2000, a total of 36 men (12 patients with diabetic etiology, 5 patients with vasculogenic risk factor) were enrolled in this study. The mean age of patients was 53 (27-67) years. Following standard questionnaires, including a detailed anamnesis from an andrologic viewpoint, VST was performed in an ambulatory setting and beginning with a test dose of 50 mg. At the end of 2 h, the data was evaluated with computer assistance (Rigiscan device) and if a satisfactory erection had not occurred, an additional second dose of sildenafil citrate (50 mg) was given until there was a satisfactory erection. Results obtained from VST: results were classified as group I (fully rigidity, >10 min erection, >70% of rigidity, possible vaginal penetration), group II (unstable erection, 5 min erection, >70% of rigidity, possible vaginal penetration) and group III (tumescence without rigidity, <5 min erection, <70% of rigidity, impossible vaginal penetration). The results obtained during the first 1 h of the VSTR test were regarded as the patient's own erectile condition and later data was accepted as the real effect of sildenafil citrate. The Fisher exact test was used for statistical evaluation including pre- and post-sildenafil effect on erectile rigidity and duration of erection.

The erection status of patients was sufficient in 17 (47.2%) in group I, it was insufficient but sufficient enough with an increased dose of sildenafil citrate in 10 (27.7%) in group II, and insufficient without/with full dose of sildenafil citrate in 9 (25%) in group III. Considering rigidity and total erectile period, there was a statistical significant difference between the first two groups with respect to the early and late sildenafil citrate effects on the VSTR test (p < 0.05). Again, 10 patients with known risk factors (diabetes mellitus 5 and vasculogenic 5) in the second group seemed to give a good response to repeated dosage of sildenafil citrate which has been found to be very interesting. However, the rest of the diabetic patients (n = 7) in the third group showed no erection despite the increasing and repeated doses of sildenafil citrate.

Sildenafil citrate with the VSTR test has effective and reliable results which was regarded as very important to diagnose and determine objectively the amount of therapeutic doses in impotence. In accordance with the literature data, our results also confirm the reliability and the practical nature of the VSTR test, which is less time-consuming and cheaper than the nocturnal penile tumescence and rigidity (NPTR) test. In the VSTR test, necessary doses of medication needed for satisfactory erection were easily regulated in patients with certain kinds of impotence. Additionally, self-criticism advantage of the patients on erection and an unnecessary need for regular sexual partners may make this test preferable in the near future. However, we believe that a large group of patients with other definite parameters are certainly needed in order to obtain more reliable data.