Abstract Introduction In cavernovenous leakage (CVL), blood entering corpora cavernosa escapes too early due to abnormal venous network, for erections to develop or maintain. CVL diagnosis relies on persisting blood flow velocity in cavernosal arteries at the end of diastole (EDV), with a consensus 5 cm/s cut-off value at pharmacologically-challenged penile duplex sonography (PC-PDS). Objective We present clinical, hemodynamic characteristics, and response to surgery of 41 patients with severe ED resistant to PDE5Is, with EDV5 cm/s at PC-PDS, considered non pathologic, but with CVLs identified by gold standard pharmacologically-challenged penile CT-cavernography. Methods Prospectively collected data from 41 consecutive patients with ED resistant to PDE5Is, with cavernosal artery EDV5 cm/s (Group A), were compared to data from 130 patients with EDV>5 cm/s (Group B). CVLs in Group A were detected by PC-PDS on deep dorsal vein or penile superficial veins after intracavenosal injection of Prostaglandin E1 plus Papaverine. All patients had refused a penile implant and underwent CVL intervention consisting in open surgery and embolization during the same procedure. Inter-group comparison used a T-test of means, pre- and post-operative data comparison a paired t-test. Results Patients in Group A were younger than in Group B (mean age 38.2±14.0 and 45.9±11.6 years, respectively, p<.0022). Pharmacologic Erection Hardness Score (EHS) was higher (2.9±.7 vs. 2.4±.6, p<.0001), EDV velocity was less (1.6±2.2 vs. 15.1±2.2 cm/s, p<.0001) in Group A than B, respectively. Pre-operative IIEF5 score was higher in Group A than in B (13.3±5.3 and 9.4±4.8, respectively, p<.0181). Other pre-operative erection parameters were otherwise similar in the two groups (morning erection EHS and frequency, masturbation and sexual intercourse EHS, percentage of successful penetration (p<.498, .543, .682, .510, .289, respectively). Patients in Group A and B responded similarly to surgery, with a similar pharmacologic EHS increase at systematic three-month post-operative PC-PDS (0.77±.94 vs. .81±.67, p<.80). Mixing Group A and B 171 patients, at the end of the 29.8±20.4-month follow-up, a significant improvement on all clinical parameters was observed: IIEF-5 score had increased from 9.7±5.1 to 15.5±6.0 (p<.0001), clinical EHS during sexual intercourse from 2.0±.7 to 3.3±.7 (p<.0001), penetration success rate from 22.3±31.7 to 70.1±37.2% (p<.0001), mean EHS during masturbation from 2.11±.67 to 3.04±.75 (p<.0001), morning erection EHS from .95±1.24 to 2.12±1.37 (p<.0001), before and after surgery, respectively. There was no statistically significant difference between Group A and B regarding all these parameters, demonstrating similar clinical responses to surgery. Conclusions Patients with EDV5 cm/s may have CVL evidenced by PC-PDS flow analysis directly on veins, and gold standard PC-PCTC. Their erection disability is severe. They respond well to combined open and embolization surgery, a confirmation that they suffer CVL. EDV criterium misses CVL in as much as one patient out of four with actual CVL in our series. Since false negative diagnosis has severe, life-long, patient and partner implications, hemodynamic criteria for CVL diagnosis should be debated in the field of sexual medicine. Disclosure No.