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benign prostatic hyperplasia ( bph ) is the main reason for lower urinary tract symptoms ( luts ) due to urethral blockade .
there are two kinds of treatments for patients with bph : medical and surgical treatment . whereas medical treatment using alpha - blockers or 5-alpha reductase inhibitors is the first - line treatment of bph , in some ineffective cases , open prostatectomy or transurethral resection of prostate ( turp ) has been mainly applied .
delay of surgical therapy due to medical therapy can cause progression of bph and its symptoms .
recently , non - open surgery , or turp , has been more popularly used because of the lower mortality and shorter hospital stay than with open surgery .
development of equipment such as high - quality resectoscopes and fiberoptic and microlens systems and advances in the technology of turp also contribute to a higher rate of turp than open surgery .
the purpose of this article was to evaluate the annual changes in prostate variables and style of surgical treatment in patients with bph over the past 12 years .
the subjects were 918 patients ( january 1999-november 2010 ) who were treated by either open prostatectomy or turp .
for the preoperative evaluation , chest x - ray , intravenous pyelography , electrocardiography ( ecg ) , urine analysis , urine culture , blood tests , and biochemistry tests were done . in patients who were more than 60 years of age , arterial blood gas analysis ( abga ) was performed .
also , all patients underwent transrectal ultrasonography ( trus , b&k medical , herlev , denmark ) , digital rectum examination ( dre ) , and serum prostate - specific antigen ( psa ) measurement .
a monopolar electric surgical unit and 24 fr resectoscope ( karl storz , tuttlingen , germany ) and a continuous irrigation system were used until 2003 , and a 22 fr resectoscope ( karl storz , tuttlingen , germany ) since 2004 .
every year , the performance ratio between open prostatectomy and turp was evaluated . before surgery
all patients underwent trus by residents ( 2 second - year residents per year , 22 residents/12 years ) in our urology department .
in addition , before both turp and open prostatectomy , the peak flow rate ( pfr ; qmax ) , residual volume , and international prostate symptom score ( ipss ) were evaluated , and just after removal of the foley catheter in both surgeries , qmax , residual volume , and ipss were measured .
after turp , resected prostate tissue was obtained and measured by use of a weighing machine .
resection time was measured as the duration from start to end of cutting the prostate .
postoperative complications were comparatively analyzed . since 2006 , the residual volume and resection time were measured .
follow - up data of performance ratio , prostate volume , resection volume , resection time , ipss , and complications were analyzed by using spss ver .
comparisons of clinical characteristics and parameters were made by using the paired t - test and chi - square test .
the mean age of the 843 patients who underwent turp was 67.97.2 years ( range , 46 - 88 years ) and the mean age of the 75 patients who underwent open prostatectomy was 72.16.3 years ( range , 58 - 83 years ) .
the mean total volume of turp was 43.619.4 cc ( range , 14 - 98 cc ) and that for open prostatectomy was 102.131.3 cc ( range , 52 - 213 cc ) .
the mean weight of the resected volume was 18.716.2 cc ( range , 2 - 54 cc ) in the turp group and 81.336.7 cc ( range , 21 - 140 cc ) in the open prostatectomy group . in the turp group ,
the mean preoperative ipss score was 21.88.2 and the mean postoperative ipss score was 14.611.9 .
in the open prostatectomy group , the mean preoperative ipss score was 22.38.4 and the mean postoperative ipss score was 14.77.6 . between the turp and open prostatectomy groups , total prostate volume , transitional zone volume , and resection volume
were significantly different ( p<0.001 , p=0.024 , p<0.001 , respectively ) ( table 1 ) .
the performance ratio between open prostatectomy and turp treatment was 64% vs 36% in 1999 and 3% vs 97% in 2010 . in 2001
the performance ratio of turp started to increase over open prostatectomy as 94.5% vs 5.5% , and during 2001 through 2010 , the performance ratio of turp greatly increased ( table 2 , fig .
1 ) . from 1999 to 2010 , the total prostate volume of the turp group increased from 40.0 cc to 55.0 cc , which was a significant difference ( p=0.031 ) ( table 2 , fig .
, the total prostate volume also showed an increase from 74.1 cc to 116.7 cc in the open prostatectomy group , which was a significant difference ( p=0.016 ) ( table 2 , fig .
the mean resection volume of the turp group increased from 2.3 cc to 20.1 cc , which was a significant difference ( p<0.001 ) ( table 2 , fig .
also , the mean resection volume of the open prostatectomy group increased from 59.3 cc to 114.3 cc , which was a significant difference ( p=0.025 ) ( table 2 , fig .
the surgeon preferred to perform open prostatectomy rather than turp , because the operator was not as experienced with turp as with open prostatectomy . from 2006 to 2010 , the residual volume of the prostate after turp decreased from 29.3 cc to 24.7 cc . from 1999 to 2010
the resection time of the turp group decreased from 72.9 minutes to 43.2 minutes , which was significant difference ( p=0.031 ) ( table 2 ) . also , the resection volume per minute of turp increased from 0.03 cc to 0.46 cc ( fig .
3 ) . there was no significant difference between postoperative qmax and postoperative ipss in 1999 to 2010 .
urethral dilatation and internal urethrotomy to treat the urethral stricture gradually increased between 1999 and 2005 such as from 4.0% to 49.1% . between 2005 and 2010 ,
4 ) . there was no significant difference between the frequency of cystocatheterization and reoperation due to postoperative bleeding . also , the performance ratio , total prostate volume , and resection volume were higher and resection time was lower in the turp group who underwent the procedure with the 22 fr resectoscope from 2004 to 2010 .
regardless of resectoscope size , the performance ratio , total prostate volume , and resection volume increased annually and resection time decreased annually .
also , the incidence of urethral stricture after turp was not significantly different in either group ( p=0.131 ) ( table 3 ) .
bph , the most common benign neoplasm in men , is clinically followed by luts .
these variable symptoms range from incomplete emptying , nocturia , weak stream , to frequency and can potentially advance to urge incontinence , urinary retention , urinary tract infection ( uti ) , bladder calculi , or renal failure .
luts impede habitual activities and reduce quality of life . in order to relieve bladder outlet obstruction ,
, stearns developed the tungsten loop , which could be used for the resection , and the transurethral resection procedure widely spread .
the indications for tur are as follows : complete urinary obstruction with prostate blockade syndrome , urinary obstruction symptoms , recurrent bleeding , and recurrent uti . with the increase in the population of old aged persons and
are patients in their 60s and 70s who need to be operated on because they have diseases such as lung disease , diabetes mellitus , and hypertension .
tur can be conducted in persons who can live longer than 6 months with other internal organ tumors .
the selection of a treatment method can be accomplished by considering the patient 's physical condition , accompanying diseases , the size and shape of the prostate , expected complications , and surgeon 's technique .
turp still represents the surgical treatment of choice for prostate glands up to 100 ml , whereas open prostatectomy is indicated for prostate glands larger than 80 to 100 ml . generally , in cases of much more than 100 g of prostate volume , open prostatectomy will be recommended .
however , kwak et al reported on a comparison between turp and open prostatectomy for patients with large bph , and there were no significant differences in effectiveness or safety for 5 years . even for patients with bph with a high volume , turp is an effective operation that can replace open prostatectomy . when selecting the proper treatment methods for bph , not only the many factors already listed previously but also the anticipated complications must be seriously considered .
usually , turp is conducted more often than open prostatectomy because the former is not only less invasive but also is associated with less morbidity .
turp is the gold standard for the surgical management of symptomatic bph and has proven to be a highly efficient technique associated with a low mortality rate [ 14 - 16 ] .
however , after turp , several complications such as incontinence , stricture of the urethra , and retrograde ejaculation may develop . in our data ,
urethral dilatation and internal urethrotomy to treat the urethral stricture gradually increased between 1999 and 2005 from 4.0% to 49.1% . between 2005 and 2010 ,
however , the rate of urethral strictures decreased from 49.1% to 9.2% . from 2006 , we started to maintain the temperature of the urethra with warm irrigation solution during transurethral resection of the prostate .
this decreased the incidence of urethral stricture compared with the room - temperature irrigation solution group .
we observed that a lower temperature might be another cause of urethral stricture after turp . the mechanical damage in the urethral mucosa leads to leakage of urine , resulting in inflammation and scar formation .
resectoscope size , however , did not have a significant relationship with the incidence of urethral stricture .
developments in anesthesia , for example , the addition of opioids to local anesthetics , have reduced the side effects of spinal anesthesia in urologic surgery . owning to new techniques , the operation time has been reduced and complications have declined . because of the high quality of the resectoscope , and the fiberoptic and microlens systems , and strict adherence to the practice of performing turp , the results of the present study also demonstrate that the safety of turp is improved by decreasing intraoperative blood loss , which significantly decreases the need for blood transfusion . for these reasons
, turp has been widely performed rather than open prostatectomy during the past 12 years in urology .
, surgeons start an operation with an easy case , which is followed by difficult ones .
the learning curve migrates from small prostate cases to large prostate cases . in our data ,
prostate volume was larger during the latter period than in the early period because of improved techniques of turp .
in addition , turp efficiency increased in proportion to prostate weight , and this study showed a continuous increase in resection volume per minute of turp .
the introduction of medical therapy for symptomatic bph resulted in a delay in the need for surgical intervention , such that a man who eventually required turp inevitably presents when older , with a worsening comorbid status , and more progressive disease , thus resulting in poorer outcomes and more frequent postoperative complications .
patients treated by turp show an increase in not only prostate volume but also resected prostate volume , which may be because the surgery was delayed by treatment with alpha-1 blockers or 5-alpha reductase inhibitors .
the volume of the prostate removed by open prostatectomy also increased , which may also have been caused by the delayed surgical effect by medication , although that should be followed up for a longer time .
from 1999 through 2010 , the performance ratio between open prostatectomy and turp was higher for turp .
the increases in prostate volume and resected prostate volume may have occurred because the surgery was delayed by the improvement in symptoms by medications .
also , the resection time and postoperative complications decreased annually as the result of improvements in surgical techniques and instruments .
purposethe purpose of this study was to evaluate the annual changes in prostate variables and style of surgical treatment of patients with benign prostatic hyperplasia ( bph ) over the past 12 years.materials and methodsthe subjects were 918 patients ( january 1999-november 2010 ) who were treated by either open prostatectomy or transurethral resection of prostate ( turp ) . 
 every year , the performance ratio between open prostatectomy and turp was evaluated . before surgery , total and transitional zone volumes of the prostate 
 were measured by transrectal ultrasonography ( trus ) . 
 after surgery , resection weight and residual volume of the prostate were measured by trus.resultsfrom 2001 through 2010 , the performance ratio of turp increased greatly from 89% to 97% . during 1999 to 2010 , the total volume of the prostate increased from 40.0 cc to 55.0 cc in the turp group and from 74.1 cc to 116.7 cc in the open prostatectomy group . during 1999 to 2010 , the mean resection volume of the turp group increased from 2.3 cc to 20.1 cc . also , the mean resection volume of the open prostatectomy group increased from 59.3 cc to 114.3 cc . during 1999 to 2003 , the resection time of the turp group decreased from 72.9 minutes to 43.2 minutes.conclusionsduring 1999 through 2010 , the performance ratio between open prostatectomy vs turp was high for turp . 
 the total volume and resection volume of the prostate increased annually , and the resection time decreased annually .