Pharmaco-induced erections for penile color-duplex ultrasound: oral PDE5 inhibitors or intracavernosal injection?

Abstract

To prospectively compare the clinical responses and penile color-duplex ultrasound (PCDU) results of oral PDE5 inhibitors (PDE5-Is) with papaverine intracavernosal injection (ICI) and to evaluate whether PDE5-Is could be used as alternatives to vasoactive agent injections, 25 ED patients underwent PCDU three times with an interval of at least 1 week, using different pharmacological induction: ICI mode (30--60 mg papaverine), sildenafil mode (100 mg sildenafil) and tadalafil mode (20 mg tadalafil). The preference of the patients was collected when all tests were completed. No significant differences were found in peak systolic velocity and acceleration time among all three modes. However for the ICI mode, end diastolic velocity of the right cavernosal artery was significantly higher than those of the sildenafil and tadalafil modes 5 min after erection induction, and at 15 min it became lower than those of two PDE5-I modes. Consequently, resistance index of the right cavernosal artery in ICI mode was reversed at 5 and 15 min. In all, 60.0 and 56.0% patients managed to reach full erection in PDE5-Is modes, which was significantly lower than in ICI mode (80.0%). Therefore, although PDE5-Is and papaverine ICI showed similar effects on PCDU parameters in detecting arterial ED, more patients had better clinical responses to ICI, and oral PDE5-Is administration still showed some pitfalls in practical use.

Current approaches to the diagnosis of vascular erectile dysfunction

“…It was found that the PSV value of proximal cavernous artery was much higher than that of distal cavernous artery in both ED patients (39.0±11.2 vs. 20.0±5.6 cm/s) and normal controls (39.8±8.0 vs. 21.3±5.5 cm/s) (55). There may also be differences in PSV values between the left and right cavernous arteries (58). A difference of more than 20 percent between the two arterial regions of the penis was considered suspicious of arterial insufficiency (39).…”

Intracavernosal Injection for the Diagnosis, Evaluation, and Treatment of Erectile Dysfunction: A Review

“…also reported a significant difference in the number of patients able to reach full erection with ICI. Eighty percent of patients were able to reach full erection with ICI of papaverine, compared with 60% with sildenafil and 56% with tadalafil [31].…”

Effect of low‐intensity extracorporeal shockwave therapy on nocturnal penile tumescence and rigidity and penile haemodynamics

“…Cavernous arterial diameters and haemodynamics were measured at baseline before pharmaco-induced erection and commonly every 5 min afterwards up to 20 min. Pharmaco-induced erection procedure (Yang et al, 2011(Yang et al, , 2012: patients were asked to take sildenafil (Viagra) 100mg 1 hr in advance. Audiovisual sexual stimulation (AVSS) and masturbation stimulation were synchronously given 15 min before the erection test.…”