Dynamic penile eco colorDoppler (ECDP) shows limits of specificity in case of differential diagnosis between functional (adrenergic hypertone) and organic cavernovenous incompetence. The aim of this study is the evaluation of a new flow chart for venogenic erectile dysfunction diagnosis, including power Doppler (PD), avoiding the repetition of ECD with higher concentrations of PGE1. In fact this procedure is invasive, often painful and burdened by a consistent risk of priapism. Patients suspected of caverno-venous incompetence underwent PD during the ECD. 85 of them showed high telediastolic velocity but normal systolic peak flow. All these patient underwent PGE1 redosing, to a maximum of 40 micrograms. Patients with still suspicious ECD were administered RigiScan. 63 patients over 85 had good PD, while 22 had bad PD. Of the 63 patients with good PD, 60 (95%) had normal ECD after redosing, while in 3 (5%) of them the telediastolic velocity remained high. In these 3 patients RigiScan showed normal nocturnal rigidity in 2 cases, abnormal in 1. 18 patients (82%) of the 22 with bad PD never showed improvement of ECD and RigiScan resulted altered in 15. In our opinion concordance between 10 micrograms ECD and PD avoids redosing in demonstrating organic venogenic erectile dysfunction. If PD is good but ECD is altered, 10 micrograms re-dosing could help in differentiating organic or functional erectile dysfunction. The diagnostic flow chart, then, should always include PD.