Experimental data support the concept of cavernosal damage and suggest a protective role for daily dosage of a PDE5-I ; however , similar data have not yet been replicated in humans .
Penile rehabilitation programs are common in clinical practice , but there is no definitive evidence to support their use or the best treatment strategy .
PDE5-Is are efficacious and safe in young patients with normal preoperative erectile function who have undergone bilateral nerve-sparing radical prostatectomy .
On-dem and use of a PDE5-I may be at least as efficacious as daily use .
PDE5-I use in penile rehabilitation programs is not supported by rigorous level 1 evidence -based medicine .
PDE5-Is are an efficacious and safe treatment for post-RP ED in properly selected patients .
The experimental results on the protective role of daily dosages of PDE5-Is , while robust , have not been replicated in humans .
CONTEXT  Erectile dysfunction ( ED ) after radical prostatectomy ( RP ) has a significant negative impact on a patient 's health-related quality of life .
Phosphodiesterase type 5 inhibitors ( PDE5-Is ) have recently been utilized not only as a treatment of ED in this population but also as a preventive strategy in penile rehabilitation programs .
OBJECTIVE To eluci date the pathophysiologic mechanisms of post-RP ED , to assess the need for rehabilitation following surgery , and to analyze the basic scientific evidence and clinical applications of PDE5-Is for the prevention and treatment of ED .
EVIDENCE SYNTHESIS Post-RP ED has many factors .
Cavernosal nerve injury induces pro-apoptotic factors ( ie , loss of smooth muscle ) and pro-fibrotic factors ( ie , an increase in collagen ) within the corpora cavernosa .
Safety and efficacy of vardenafil for the treatment of men with erectile dysfunction after radical retropubic prostatectomy.
PURPOSE More than one-third of men may experience erectile dysfunction ( ED ) after nerve sparing radical retropubic prostatectomy . The efficacy and safety of vardenafil , a potent , selective , phosphodiesterase 5 inhibitor , was assessed for the treatment of ED after radical prostatectomy . MATERIAL S AND METHODS In this double-blind study 440 men with ED after nerve sparing radical prostatectomy were r and omized to take placebo , or 10 or 20 mg vardenafil .  Efficacy was measured after 12 weeks using the erectile function domain of the International Index of Erectile Function , diary questions measuring vaginal penetration and intercourse success rates , and a global assessment question ( GAQ ) on erection . RESULTS Of the intent to treat population 70 % had severe ED ( erectile function less than 11 ) at baseline . After 12 weeks both vardenafil doses were significantly superior to placebo ( p < 0.0001 ) for all efficacy variables . Improved erections ( based on GAQ ) were reported by 65.2 % and 59.4 % of patients on 20 and 10 mg vardenafil , respectively , and by only 12.5 % of patients on placebo ( p < 0.0001 ) . Among men with bilateral neurovascular bundle sparing , positive GAQ responses were reported by 71.1 % and 59.7 % of patients on 20 and 10 mg vardenafil , respectively , versus 11.5 % of those on placebo ( p < 0.0001 ) . The average intercourse success rate per patient receiving 20 mg vardenafil was 74 % in men with mild to moderate ED and 28 % in men with severe ED , compared to 49 % and 4 % for placebo , respectively . Few adverse events were observed . They were generally mild to moderate headache , flushing and rhinitis . CONCLUSIONS In men with severe ED after nerve sparing radical retropubic prostatectomy , vardenafil significantly improved key indices of erectile function
Experimental data support the concept of cavernosal damage and suggest a protective role for daily dosage of a PDE5-I ; however , similar data have not yet been replicated in humans .
Penile rehabilitation programs are common in clinical practice , but there is no definitive evidence to support their use or the best treatment strategy .
PDE5-Is are efficacious and safe in young patients with normal preoperative erectile function who have undergone bilateral nerve-sparing radical prostatectomy .
On-dem and use of a PDE5-I may be at least as efficacious as daily use .
PDE5-I use in penile rehabilitation programs is not supported by rigorous level 1 evidence -based medicine .
PDE5-Is are an efficacious and safe treatment for post-RP ED in properly selected patients .
The experimental results on the protective role of daily dosages of PDE5-Is , while robust , have not been replicated in humans .
CONTEXT  Erectile dysfunction ( ED ) after radical prostatectomy ( RP ) has a significant negative impact on a patient 's health-related quality of life .
Phosphodiesterase type 5 inhibitors ( PDE5-Is ) have recently been utilized not only as a treatment of ED in this population but also as a preventive strategy in penile rehabilitation programs .
OBJECTIVE To eluci date the pathophysiologic mechanisms of post-RP ED , to assess the need for rehabilitation following surgery , and to analyze the basic scientific evidence and clinical applications of PDE5-Is for the prevention and treatment of ED .
EVIDENCE SYNTHESIS Post-RP ED has many factors .
Cavernosal nerve injury induces pro-apoptotic factors ( ie , loss of smooth muscle ) and pro-fibrotic factors ( ie , an increase in collagen ) within the corpora cavernosa .