A total of 35 participants who underwent penile revascularization surgery with the diagnosis of vascular ED in our clinic were included in this study. Detailed anamnesis of the cases was taken, including age, duration of ED, comorbidities that may cause ED, previous trauma, medical or surgical history and lifestyle. After the physical examination, IIEF 5/15 questionnaires were filled out. In order to exclude hypogonadism, follicle stimulating hormone(FSH), luteinizing hormone(LH), total testosterone and prolactin levels were measured in the preoperative period. PCDU, CC-EMG and cavernosometry tests were applied to all participants in the preoperative period. Participants that did not benefit from phosphodiesterase 5 inhibitors(PDE-5I) and intracavernosal alprostadil injection used in the preoperative period were included in the study. Cases with a history of urogenital, rectal and similar operations that may affect erectile functions, cases with penile pathologies such as Peyronie's disease, and cases with ED of neurogenic and psychogenic origin were excluded from this study. After the 3rd postoperative month, participants were interviewed face to face. During these follow up, the patients were re-evaluated with the IIEF-5/15 questionnaires, and PCDU and computurized tomography angiography (CTA) was performed.

PCDU technique: The PCDU was performed in a quiet and comfortable room for the participants' comfort. For the diagnosis of arterial insufficiency or veno-occlusive disease, PCDU(B-K Medical, Herlev, Denmark) was performed with the patient lying in the supine position. First, gray scale imaging of the flaccid penil shaft in transverse and sagittal planes was performed to exclude intracavernosal fibrosis and calcifications. Then, 60 mg papaverine hydrochloride (Papaverine HCl®, Galen Medical Industry, Turkey) was injected laterally into any of the corpus cavernosum with a 22 Gauge needle. 20 minutes after papaverine HCl injection, PCDU was performed with an 8 Megahertz (MHz) linear probe at an angle of approximately 45 degrees. PSV, EDV, RI values of both cavernosal arteries and anastomosis region were calculated. Measurements were repeated at 5-minute intervals and continued for 30 minutes. Participants with PSV\<25 cantimeters/second (cm/s) were interpreted as arterial insufficiency, and participants with PSV\>25 cm/s, EDV \>5 cm/s and RI\<0.85 were interpreted as veno-occlusive disease. RI was calculated with the formula \[RI=(PSV-EDV)/PSV\]. Participants were warned about the risk of priapism after papaverine HCl injection and were asked to immediately consult the clinic if the erection persisted after four hours.

CC-EMG technique: Penil cavernous electrical activity (CEA) was recorded using a high-speed electromyography module equipped with a computer (Medical Measurement Systems, Enschede, the Netherlands). The sampling frequency was 200 Hertz (Hz), and a band-pass ﬁlter with a cut-off frequency of 0.1-20 Hz was used. During the CC-EMG recordings, monopolar needle electrode was used to measure the CEA. A grounding electrode was placed to the participants' foot to avoid electrical activity simultaneously originating from non-penil areas. It appears as a single line in the CC-EMG recording. CC-EMG recordings were started after the participants rested for 10 minutes in a quiet and dim room. CEA potentials were recorded for 10 minutes. Later the CEA potentials of the penil cavernous nerves was assessed by detecting the peak-to-peak amplitudes. Ten minutes later, papaverine HCl (60 mg) was injected into a single cavernous body for avoiding the pattern of discoordination, which manifested by an increase or no difference in the CEA recording following the injection and suggested the neurogenic ED. Participants with a discoordination pattern were not included in the study. The relaxation degree (RD) was calculated using the formula: RD=Pre-injection CEA-Post-injection CEA/Preinjection CEA×100, as previously described. Participants having less than 50% RD were excluded from the study.

Cavernosometry technique: After CC-EMG recordings were made, cavernosometry was conducted with the same device. In the presence of the following criteria, a diagnosis of caverno-occlusive dysfunction was made.

1. Requires a maintenance flow rate greater than 5 milliliters/minute (ml/m) after revealed an intracavernous pressure of 150 millimeters-Hg (mmHg) with the artificial erection test.
2. The intracavernous pressure decreased by a minimum of 45 mmHg within 30 second following the termination of infusion.

Surgical technique: The operations, were conducted using the Furlow-Fisher procedur, of the Virag-V technique. Unlike the Furlow- Fisher procedure, the circumﬂex collaterals were preserved, and the deep dorsal venous valves were not disrupted by a stripper. After the IEA was brought to the penil root through the subcutaneous tunnel, an end-to-side anastomosis was performed with the proximal part of the deep dorsal vein. 7-0 polypropylene suture were used according to a standard microsurgical procedure. After the anastomosis, the deep dorsal vein was ligated proximal to the arteriovenous anastomosis. The procedure was performed under optical magnification (x2.5) to prevent neurovascular bundle damage. In the postoperative period, intravenous heparin (5000 IU/day) was prescribed for 3 days, 75 mg/day dipyridamole and 300 mg/day acetylsalicylic acid daily for three months. He was warned not to have sexual intercourse for 2 months after the operation.

CTA technique: In the third postoperative month, participants underwent CTA. 60 milligram (mg) papaverine HCl was administered to the subjects 10 minutes before the shooting. A 22-gauge branule was placed in the basilic or cephalic vein of the patient's forearm. Then, the patient was placed supine on the imaging stretcher and the area to be imaged was determined. Then, using an automatic injector pump, iodinated contrast material(Iopromide, Ultravist®, Schering, Germany) was given to the patient intravenously at a dose of 2 mg/kg and at a flow rate of 3 ml/s. Then, arterial phase pelvic CTA with 2 mm slice thickness was performed with a 64-detector, multi detector CT machine (Aquilion 64, Toshiba®, Tokyo, Japan). After CTA examination, sagittal and coronal reformatted images(slice thickness: 1 mm) were obtained. CT images were evaluated by an experienced radiologist.