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benign prostatic hyperplasia ( bph ) is commonly seen in elderly men starting at 40 years of age .
bph often presents as lower urinary tract symptoms ( luts ) due to difficulties in voiding and irritability of the bladder .
transurethral resection of the prostate ( turp ) has been considered the reference treatment for bph for the past 30 years .
however , turp , the standard surgical therapy for the relief of luts , is reported to cause erectile dysfunction ( ed ) , although some patients with preexisting ed reported improved erectile function after turp .
thus , recent evidence from both community and clinical trials has suggested a link between bph - induced luts and erectile function .
the aim of this study was to evaluate erectile function after turp in a hospital by use of the validated international index of erectile function ( iief ) .
a second aim was to identify the possible factors associated with the occurrence of ed in this particular patient cohort .
between january 2008 and august 2009 , 108 patients who underwent turp were retrospectively evaluated .
all patients also underwent transrectal ultrasound ( trus , b&k medical , herlev , denmark ) .
in addition , medical history , prostate - specific antigen ( psa ) , flow rate , urine residue , and international prostate symptom score ( ipss ) were recorded for those who presented without a catheter .
finally , the erectile function of the patient was evaluated according to the iief questionnaire .
the flow rate , ipss , and iief questionnaire were reevaluated at 1 , 3 , and 6 months postoperatively .
as much prostate adenomatous tissue as possible was removed as far as the surgical capsule .
an 18 french foley catheter was inserted in all patients and was removed when hematuria sufficiently diminished .
after removal of the catheter 2 - 5 days after the operation , a voiding trial was performed .
we used the iief score , which was calculated 1 month before the operation and 1 , 3 , and 6 months after the operation , to compare the change in erectile function .
all domains included in the iief were compared with the ipss and other items . because the patients in this study had generally decreased sexual activities
because the range that divided the total score for the ef domain was 5 points , we divided the patients into 3 groups and defined them as follows : patients who had less than 5 points were defined as the impaired erectile function group , those who had more than 5 points were defined as the improved erectile function group , and those between the two groups mentioned above were defined as the no influence on erectile function group ( the data that we compared were the ef domain questionnaire completed before the operation and that completed 6 months after the operation . ) .
the first group consisted of patients who had erectile function before the operation but had no erectile function after the operation .
the second group were those who had no erectile function before the operation but recovered erectile function after the operation .
finally , the third group were those who did not show any change in erectile function before or after turp .
we analyzed the data with the statistical package for the social sciences 16.0 for windows ( spss inc . ,
comparisons of clinical characteristics and parameters were made by using the paired t - test and chi - square test .
between january 2008 and august 2009 , 108 patients who underwent turp were retrospectively evaluated .
all patients also underwent transrectal ultrasound ( trus , b&k medical , herlev , denmark ) .
in addition , medical history , prostate - specific antigen ( psa ) , flow rate , urine residue , and international prostate symptom score ( ipss ) were recorded for those who presented without a catheter .
finally , the erectile function of the patient was evaluated according to the iief questionnaire .
the flow rate , ipss , and iief questionnaire were reevaluated at 1 , 3 , and 6 months postoperatively .
as much prostate adenomatous tissue as possible was removed as far as the surgical capsule .
an 18 french foley catheter was inserted in all patients and was removed when hematuria sufficiently diminished . after removal of the catheter 2 - 5 days after the operation , a voiding trial was performed .
we used the iief score , which was calculated 1 month before the operation and 1 , 3 , and 6 months after the operation , to compare the change in erectile function .
all domains included in the iief were compared with the ipss and other items . because the patients in this study had generally decreased sexual activities
because the range that divided the total score for the ef domain was 5 points , we divided the patients into 3 groups and defined them as follows : patients who had less than 5 points were defined as the impaired erectile function group , those who had more than 5 points were defined as the improved erectile function group , and those between the two groups mentioned above were defined as the no influence on erectile function group ( the data that we compared were the ef domain questionnaire completed before the operation and that completed 6 months after the operation . ) .
the first group consisted of patients who had erectile function before the operation but had no erectile function after the operation .
the second group were those who had no erectile function before the operation but recovered erectile function after the operation .
finally , the third group were those who did not show any change in erectile function before or after turp .
we analyzed the data with the statistical package for the social sciences 16.0 for windows ( spss inc .
comparisons of clinical characteristics and parameters were made by using the paired t - test and chi - square test .
the comparative analysis between the three groups was performed by using anova . for all statistical comparisons ,
a total of 29 patients were excluded from the analysis , including 3 who were diagnosed with prostate carcinoma after surgery , 3 who had a urethral stricture after transurethral prostatic resection and underwent urethrotomy , and 23 who refused to complete the erectile function questionnaire .
the mean patient age was 67.5 years ( range , 55 - 80 years ) , the average amount of resected tissue was 26.5 g ( range , 5 - 82 g ) , and the mean resection time was 64 minutes ( range , 22 - 115 minutes ) . histopathological examination revealed bph in all patients . before and 6 months after turp , the mean residual urine volume was reduced from 105.1126.0 ml to 46.033.3 ml ( p<0.01 ) .
the maximum flow rate improved from 10.15.4 ml / s to 15.58.7 ml / s ( p<0.01 ) .
as shown in the table , the patients ' symptoms improved greatly after turp ( table 2 ) . in the analysis at 1 and 3 months after turp ,
six months later , however , there was no longer a statistically significant decrease in the postoperative ef domain score compared with the preoperative ef domain score ( p<0.08 ) ( table 3 ) .
nine patients had erectile function before the operation but had full ed after the operation ( 11% ) , and 6 patients had full ed before the operation but recovered erection after the operation ( 8% ) .
a total of 12 patients ( 14% ) had an increased ef domain score after the operation , and 23 patients ( 28% ) had a decreased ef domain score after operation .
capsular perforation had no significant difference in the two groups ( p<0.64 , p<0.09 ) .
interestingly , however , the recovered erectile function group show a more decreased ipss - related score than did the full ed group after turp : total ipss score , -15.7 vs. -10.0 ( p<0.1 ) ; voiding symptom score , -7.5 vs. -6.6 ( p<0.2 ) ( table 4 ) . the increased ef domain score group had a more decreased ipss - related score than did the decreased ef domain score group : total ipss score , -11.6 vs. -9.0 ( p<0.40 ) ; voiding symptom score , -7.1 vs. -5.4 ( p<0.32 ) ( table 5 ) .
bph is a common condition in elderly men and is associated with a range of erectile function . because ed also has a high prevalence in elderly men , many groups have assessed whether any causal relationship exists between bph and erectile function .
but the effect of turp on erectile function is still controversial , and the available evidence is conflicting .
erection is a complex phenomenon that involves neurological , hormonal , arterial , venous , and muscular components and that is further influenced by psychogenic , cognitive , and environmental factors .
the effect of turp on erectile function may be brought about via several different routes , including the psychogenic effect of an invasive procedure in the genital region , injury to the nerve tracts supplying the corpus cavernosum as a result of electrocoagulation , thrombosis of the cavernosal arteries , venous leakage , and injury to the nerve tracts .
many studies have reported that ed after turp occurs in between 4% and 35% of patients and that it is associated with age or pre - existing ed [ 9 - 12 ] .
most studies have reported only on the incidence of de novo ed after turp and not on the proportion of patients experiencing an improvement of erectile function . according to the results of our study
furthermore , patients could be affected by feeling pain during erection as the result of injury to the urethra .
as time goes by , however , these problems are solved , and the change can most likely be attributed to improvement in the quality of urination .
the survey showed that when patients experienced difficulty of urination caused by bph , they preferred to avoid suffering from this condition by ceasing to pursue sex .
after turp , their mental stress was released , their libido became normal , and the patients felt that their erectile ability improved .
several authors have reported that capsular perforation is a potential risk factor for developing erectile dysfunction after turp .
however , in our study , capsular perforation had no significant correlation with erectile function .
we think that ed related to capsular perforation may depend on the location , depth , and extent of the perforation .
our study showed that there was a significant decrease in erectile function for 3 months after turp .
although no significant correlation was detected , one interesting result was improved erectile function in the patients who had better voiding symptoms after turp .
purposethe aim of this study was to investigate the effect of transurethral resection of the prostate ( turp ) on erectile function.materials and methodsa total of 108 patients treated with turp were retrospectively evaluated . 
 all patients were evaluated 1 , 3 , and 6 months after turp by use of the international prostate symptom score ( ipss ) , international index of erectile function ( iief ) , peak urinary flow rate ( qmax ) , and post - void residual urine ( pvr).resultsone and 3 months after turp , the erectile function domain score of the iief was significantly decreased . however , after 6 months , there was no longer a significant decrease in the erectile function domain score . 
 the change in erectile function was compared with the ipss score . 
 there was no statistically significant correlation , but patients who had better voiding symptoms after turp had improved erectile function.conclusionsour study showed that there was a significant decrease in erectile function for 3 months after turp . 
 however , no significant change in erectile function was observed 6 months after turp .