Objective: To evaluate the 5-item version of the international index of erectile function (IIEF-5) as a method to differentiate the causes of vasculogenic erectile dysfunction (ED).
Methods: In all, 103 ED patients (mean age 46.8 +/- 18.7) were reviewed by IIEF-5. Penile blood flow was also assessed in each patient after an intracavernosal injection (ICI) and audio-visual sex stimulation by duplex Doppler ultrasonography. The 99mTc-(113m)In dual radioisotope test was performed to confirm specific vascular causes in the vasculogenic ED cases. Kruskal-Wallis TEST was employed to compare the scores of IIEF-5 with the results of ICI, duplex Doppler ultrasonography and the 99mTC-(113m)In dual radioisotope test.
Results: Of the total number of ED cases, 37 (37/103, 35.9%) were nonvasculogenic, 18 (18/103, 17.5%) arteriogenic, 35 (35/103, 34.0%) venogenic and 13 (13/103, 12.6%) combined vasculogenic. There was no significant difference in the IIEF-5 scores either between the vasculogenic group and the non-vasculogenic one (P = 0.253) or among different groups of the vasculogenic ED patients.
Conclusion: IIEF-5 cannot be used as a tool for differential diagnosis of vasculogenic ED, or to compare its specific vascular causes, nor can the scores of IIEF-5 reflect penile vascular conditions.