[Methodology of penile isotope imaging. Evaluation].

Aims: Duplex ultrasonography and pulsed doppler analysis or dynamic infusion cavernosometry and cavernosography are used for functional evaluation of penile arterial or venous dynamics during a pharmacological erection. The accuracy of the echographic investigations is correlated to the investigator experience. Cavernosometry and cavernosography are more invasive technique than the radioisotope erection penogram, which is a reproductive and reliable test.

Material And Methods: We investigate 60 patients. Neurological, psychological and endocrinological etiology are excluded. The technique is described: thyroid is blocked by potassium perchlorate, bloodpool is labelled with Tc99m, a dynamic study is performed over 60 mn with intracavernous injection of PGE1 5g or Papaverine 30 mg at T10mn, ROIS are defined by computer processing, a phalogram curve is provided.

Results: This noninvasive test sorts out arteriogenic, venogenic and psychogenic impotence by a qualitative curve analysis. The quantitative parameters depending on numerous time consuming variables have proved to be of poor clinical use and non significant. We objectivate 20 psychogenic impotence, 27 arteriogenic impotence, 7 venous leakage and 6 mixed (arteriogenic and venogenic) impotence. Statistic evaluation of arteriogenic lesions comparative by doppler technique reveals a sensitivity of 83% and a specificity of 87%. The advantages of the test are; ambulatory, objective, noninvasive and reliable investigation. In the same time, "qualitative" data evaluates the response to a pharmacological induced erection.

Conclusions: The radioisotope erection penogram is a noninvasive, reproductive and reliable screening test for vasculogenic impotence.