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 .
The use of an erectogenic pharmacotherapy regimen following radical prostatectomy improves recovery of spontaneous erectile function.
PURPOSE It has been suggested that postradical prostatectomy ( RP ) erectile function outcomes are improved by early use of erectogenic medications . This analysis was design ed to assess the ability of a post-RP vasoactive drug program to improve long-term spontaneous erectile function . METHODS Men with functional preoperative erections who underwent RP were challenged early postoperatively with oral sildenafil . Nonresponders were switched to intracavernosal injection therapy ( ICI ) . Patients were instructed to inject three times a week . Only patients who presented within 6 months post RP , who completed the International Index of Erectile Function ( IIEF ) question naire on at least three separate occasions after surgery , and who had been followed for at least 18 months were included . Data from men who were committed to rehabilitation were compared with those of men who did not follow the protocol but continued to be followed serially following RP . RESULTS There were 58 patients in the rehabilitation ( R ) group and 74 in the nonrehabilitation ( NR ) group . No differences existed in mean patient age , comorbidity profile , intraoperative nerve sparing status , or postoperative erectile hemodynamics between the two groups . At 18 months post RP , there were statistically significant differences between the two groups in the percentage of patients who were capable of having medication-unassisted intercourse ( R=52 % vs. NR=19 % , P<0.001 ) ; mean erectile rigidity ( R=53+/-21 % vs. NR=26+/-43 % , P<0.01 ) ; mean IIEF erectile function ( EF ) domain scores ( R=22+/-6 vs. NR=12+/-14 , P<0.01 ) ; the percentage of patients with normal EF domain scores ( R=22 % vs. NR=6 % , P<0.01 ) ; the percentage of patients responding to sildenafil ( R=64 % vs. NR=24 % , P<0.001 ) ; the time to become a sildenafil responder ( R=9+/-4 vs. NR=13+/-3 months , P=0.02 ) ; and the percentage of patients responding to ICI ( R=95 % vs. NR=76 % , P<0.01 ) . CONCLUSIONS The data generated from this nonr and omized study indicate that a pharmacologic penile rehabilitation protocol results in higher rates of spontaneous functional erections and erectogenic drug response after RP
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 .