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 .
Treatment of erectile dysfunction with sildenafil.
OBJECTIVES To determine the efficacy of sildenafil for the treatment of erectile dysfunction ( ED ) in a clinical practice setting ; to evaluate the correlation between patient and partner perceptions of treatment outcomes ; and to assess the relation between the severity of ED and response to treatment . METHODS Among the first 100 men to receive sildenafil in a urology practice setting , 74 ( mean + SD age 64+/-11 years ) completed a vali date d sexual function question naire ( International Index of Erectile Function [ IIEF ] ) before and after a 4 to 6-week treatment period . A modified version of the same question naire was independently completed by partners . ED was categorized into a severity class of I to IV . RESULTS Sildenafil treatment improved erections by 71 % to 95 % , according to responses in key IIEF questions 3 and 4 . Overall , 57 ( 77 % ) of 74 patients desired to continue treatment after the test period . Patient score on the IIEF was correlated with partner score on the modified question naire before and after treatment ( r = 0.67 to 0.81 , P < 0.01 ) . IIEF scores were reflected in a simple severity classification system . Men with the best preservation of erections ( severity class I ) exhibited the best responses to sildenafil , whereas men with no erections ( severity class IV ) were much less likely to respond to the drug and desire continuation of treatment ( P < 0.01 ) . Patients with a radical prostatectomy were relatively refractory to sildenafil , except for 2 of 5 who had undergone a nerve-sparing operation . CONCLUSIONS In clinical practice , sildenafil is an effective treatment of ED , according to partner-vali date d question naire responses ; and the results of treatment are predictable with an ED severity classification system
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 .