laparoscopic pyeloplasty has emerged as the most common and widely accepted minimally invasive surgery for ureteropelvic junction obstruction ( upjo ) .
this technique has advantages of a high success rate similar to open pyeloplasty and low morbidity similar to endopyelotomy .
schuessler et al were the first authors to report on transperitoneal laparoscopic dismembered pyeloplasty in 5 patients and concluded that the procedure , though time - consuming , was a feasible treatment option for upjo .
janetschek et al were the first authors to report on retroperitoneoscopic dismembered pyeloplasty and concluded that the procedure is too complicated to be a standard procedure .
since then , there have been many publications on both types of laparoscopic pyeloplasties , but the choice of whether to perform the procedure by the transperitoneal or retroperitoneoscopic route depends on the surgeon . in transperitoneal laparoscopic pyeloplasty ( tplp ) , the large peritoneal cavity allows for free movement of instruments and intracorporeal suturing , but the rate of bowel - related complications and pain are higher in comparison with retroperitoneoscopic laparoscopic pyeloplasty ( rplp ) . in rplp
limited retroperitoneal space restricts free movement of instruments and leads to difficulty in intracorporeal suturing , leading to a longer operating time , but postoperative pain and the rate of bowel - related complications are comparatively lower .
most of the published studies are either on tplp or rplp , and some have assessed a combination of both types with nonrandomized comparison and were retrospective in nature . however , the success rate for both procedures is comparable .
review of the literature shows only 1 prospective randomized study on the comparison of tplp and rplp for primary upjo . in view of the excellent outcome results of both techniques in isolation with advantages and disadvantages of both procedures
, we executed a prospective randomized trial of tplp versus rplp for primary upjo , aiming to determine which technique is better with respect to success rate and postoperative pain and complications .
in this prospective randomized study , a total of 112 patients who underwent primary upjo were included , from january 2008 to december 2012 .
ethical approval was received in accordance with the declaration of helsinki . clinical history and findings of general physical and abdominal examinations
patients were examined by routine hemogram , renal function tests , liver function tests , coagulation profile , urine culture , and sensitivity .
we performed renal ultrasonography ; intravenous urogram ( ivu ) ; contrast computed tomography ( ct ) scans of the kidney , ureter , and bladder ; and diuretic renogram using tc - diethylenetriamine penta - acetic acid ( dtpa ) scans .
for grading of hydronephrosis , we used society for fetal urology universal criteria ( table 1 ) . from dtpa scans , split renal function and subrenal obstruction were documented .
spiral ct scans showed anterior crossing vessels at the ureteropelvic junction ( upj ) in 44 patients .
patients with a deranged coagulation profile , previous renal surgery , malrotated kidneys , huge hydronephrotic kidneys , or vertebral - spinal deformities were excluded from the study . after providing written informed consent , patients were randomized into 2 groups at a 1:1 ratio based on systematic random sampling .
group i consisted of tplp patients , and group ii comprised rplp patients . with the patients under general anesthesia , cystoscopy and retrograde ureteropyelography were performed before surgery .
comparison of baseline characteristics in tplp and rplp groups asa = american society of anesthesiologists ; bmi = body mass index .
the patient was placed in the kidney position , carbon dioxide pneumoperitoneum created , and the procedure performed with 3 ports .
anterior crossing vessels were identified in 21 cases and were dissected to free them from the upj .
the stenotic / aperistaltic segment of the ureter was excised , and the ureteric end was spatulated laterally for about 2.5 cm .
40 polyglactin as a continuous suture over a 6f/26-cm double - j stent . in patients with anterior crossing vessels ,
after this , the rest of the pelvis was closed with continuous no . 40 polyglactin suture .
the patient was placed in the kidney position , and the retroperitoneal space was created by a combination of blunt finger and indigenous balloon dissection methods .
the stenotic / aperistaltic ureteric segment was excised , the ureteric end was spatulated for about 2.5 cm , and a 6f/26-cm double - j stent was inserted .
there were multiple stones ( 20 stones ) , which were removed with a flexible cystoscope .
the tube drain was removed after 24 to 48 hours depending on the drain output .
the visual analog scale ( vas ) score for pain was determined on postoperative day 1 and day 2 .
a liquid diet was allowed once bowel sounds had returned , and the diet was increased gradually .
the foley catheter was removed on the second to third postoperative day , and the patient was discharged with advice of taking medications including suppressive antibiotic .
patients who were symptomatic at follow - up were examined with renal ultrasonography , ivu , and dtpa scans .
these patients were then followed up every 3 months , and dtpa scans were performed every 12 months .
immediate and long - term postoperative complications were recorded using the modified clavien grading system .
statistical analysis was performed with spss software ( version 16.0 ; spss , chicago , illinois ) using the fisher exact test ,  test , and mann - whitney u test , and p < .05 was considered statistically significant .
correlation was considered strong if the correlation coefficient ( r ) was > 0.5 or < 0.5 .
the patient was placed in the kidney position , carbon dioxide pneumoperitoneum created , and the procedure performed with 3 ports .
anterior crossing vessels were identified in 21 cases and were dissected to free them from the upj .
the stenotic / aperistaltic segment of the ureter was excised , and the ureteric end was spatulated laterally for about 2.5 cm .
40 polyglactin as a continuous suture over a 6f/26-cm double - j stent . in patients with anterior crossing vessels ,
after this , the rest of the pelvis was closed with continuous no . 40 polyglactin suture .
the patient was placed in the kidney position , and the retroperitoneal space was created by a combination of blunt finger and indigenous balloon dissection methods .
the stenotic / aperistaltic ureteric segment was excised , the ureteric end was spatulated for about 2.5 cm , and a 6f/26-cm double - j stent was inserted .
there were multiple stones ( 20 stones ) , which were removed with a flexible cystoscope .
the tube drain was removed after 24 to 48 hours depending on the drain output .
the visual analog scale ( vas ) score for pain was determined on postoperative day 1 and day 2 .
a liquid diet was allowed once bowel sounds had returned , and the diet was increased gradually .
the foley catheter was removed on the second to third postoperative day , and the patient was discharged with advice of taking medications including suppressive antibiotic .
patients who were symptomatic at follow - up were examined with renal ultrasonography , ivu , and dtpa scans .
these patients were then followed up every 3 months , and dtpa scans were performed every 12 months .
immediate and long - term postoperative complications were recorded using the modified clavien grading system .
statistical analysis was performed with spss software ( version 16.0 ; spss , chicago , illinois ) using the fisher exact test ,  test , and mann - whitney u test , and p < .05 was considered statistically significant .
correlation was considered strong if the correlation coefficient ( r ) was > 0.5 or < 0.5 .
a total of 112 patients were included , with 56 patients in group i ( tplp ) and 56 patients in group ii ( rplp ) .
open conversion was performed in 1 patient in the tplp group and 2 patients in the rplp group .
the laparoscopic procedures were successfully completed in 109 patients : 55 in the tplp group ( 98.2% ) and 54 in the rplp group ( 96.4% ) .
the demographic characteristics of the patients were comparable in both groups ( table 1 ) .
anterior crossing vessels were present in 44 cases ( 39.2% ) ( table 1 ) .
caliceal stones were present in 4 patients in group i and 6 patients in group ii ( table 1 ) .
the differences in total operative time and intracorporeal suturing time were statistically significant between the 2 groups ( table 2 ) .
the vas pain score was significantly higher and the requirement for tramadol on the first postoperative day and hospital stay were significantly greater in the tplp group ( table 2 ) .
postoperative complications ( according to the modified clavien grading system ) were seen in 14.8% of patients ( table 3 ) .
clavien grade i complications were seen in 3.6% of patients , grade ii in 18% , and grade iiib in 7.2% .
temporary ileus was seen in 10.8% of patients in the tplp group ( p < .027 ) ( table 3 ) .
secondary upjo was observed in 2 patients in the tplp group at a mean follow - up time of 7 months and in 2 patients in the rplp group at 6 months ; it was managed by open pyeloplasty , and postoperative dtpa scans at 3 and 12 months showed nonobstructive drainage .
the mean follow - up period of patients was comparable in both groups ( table 2 ) .
the overall success rate was 96.4% for tplp versus 96.6% for rplp with a mean follow - up period of 30.75  4.85 months versus 30.99  5.59 months ( p < .88 ) .
the pearson correlation coefficient for total operative time in rplp patients with different demographic and operative parameters did not show any significant association .
comparison of operative and postoperative results between tplp and rplp groups postoperative modified clavien complications in tplp and rplp groups uti = urinary tract infection .
schuessler et al were the first authors to describe tplp for primary upjo , in 1993 . in 1996
both of these techniques are now well established , with excellent success rates , and each has its own advantage and disadvantages . in tplp the peritoneal cavity
there are risks of bowel injury , ileus , and peritoneal contamination by leaked urine , infection , and carbonic acid .
however , tplp provides a larger peritoneal cavity for instrument handling and intracorporeal suturing . in rplp
there is minimal risk of bowel - related complications and contamination of the peritoneal cavity .
retroperitoneoscopy allows a limited working space for instrument handling and intracorporeal suturing but provides direct access to the ureteropelvic regions . in our study
the total operative time and intracorporeal suturing time were significantly higher in the rplp group .
the difference in the vas pain score on the first postoperative day , requirement for tramadol , and hospital stay were significantly higher in the tplp group ( table 2 ) .
relatively greater pain in tplp patients is due to traversing of the peritoneal cavity , manipulation , and reflection of the colon , which requires more tramadol for pain management .
anterior crossing vessels were present in 44 patients ( 39.2% ) , similar to findings previously reported in the literature . in the tplp group ,
the ureteropelvic reconstruction was performed anterior to the anterior crossing vessels , whereas in the rplp group , it was performed behind the anterior crossing vessels , in a manner similar to the tplp .
our technique was consistent with the basic principle of andersen - hynes open pyeloplasty in which transposition of the ureteropelvic anastomosis must be performed anterior to the anterior crossing vessels .
the transposition is easy to perform in tplp , but in rplp this remains a concern . in our study
we did not encounter difficulty in achieving this in rplp , and routine transposition was performed . in retroperitoneoscopy the crossing vessels are easily and better seen with simple elevation of the lower pole of the kidney , and transposition and reconstruction are not difficult to perform . in our study ,
in no cases of retroperitoneoscopy did we encounter any difficulty in performing the dismembered pyeloplasty in the presence of anterior crossing vessels .
after dissection from the upj and disconnection of the ureter from the pelvis  undergo a cephalad shifting and do not impede the reconstructive procedure .
the reconstructed ureteropelvic region , though lying anterior to the anterior crossing vessels , practically lies inferior to the vessels and hence does not create difficulty in performing anastomosis .
the crossing vessels have been postulated to be involved in the etiopathogenesis of upj and to be an indicator of poor outcome after endopyelotomy . in some studies on rplp ,
the transposition was not routinely performed ; rather , in selected cases , the vessels were dissected and placed cephalad to the upj , and ureteropelvic anastomosis was performed .
the comparison of results with or without transposition did not show any difference in outcome .
however , the selection of cases for not to transpose was not very clearly defined .
a 70-fold increased risk of stones developing in primary upjo has been reported by husmann et al .
the increased risk is not because of obstruction leading to delayed washout of urinary solutes and infection ; rather , metabolic abnormalities are the most accepted theory . in our study
caliceal stones were present in 4 patients in the tplp group and 6 patients in the rplp group .
concomitant stone extraction was performed successfully in all cases . in 1 patient with multiple stones ( 20 stones ) ,
concomitant stone extractions with a flexible nephroscope and cystoscope have similarly been reported by other authors .
the important early complications are leakage of urine from the anastomotic site , infection , and bowel - related complications .
regarding delayed complications , secondary upjo due to stenosis / stricture of the reconstructed ureteropelvic region is very important and influences the success rate of pyeloplasty . in tplp temporary ileus
ileus is a comparatively under - reported complication of transperitoneal laparoscopic surgery , and it must be recognized because it has postoperative implications in patient management . in our study
the rate of temporary ileus was significantly higher in the tplp group ; temporary ileus was also observed in some previous studies on tplp .
our study ct urogram showed a mean stricture length of 2.2 cm with grade iv hydronephrosis in all patients .
open pyeloplasty was performed , and follow - up with dtpa scan showed nonobstructive drainage .
the decision to perform open or laparoscopic pyeloplasty depends on the surgeon 's judgment and radiologic findings . in our study
the decision to perform open pyeloplasty was made because of the presence of a long stricture length and consent for open surgery .
the subjective assessment is based on clinical improvement , and the objective assessment is based on ivu ( patency of upj with decrease / absence of hydronephrosis ) and nonobstructed drainage on nuclear scans .
devenport et al , in a retrospective analysis , reported a 92% success rate for tplp versus 67% for rplp .
the drawbacks of their study were the small number of patients in the rplp group , in whom transposition of the anterior crossing vessels was not performed , and the effect of the learning curve for retroperitoneoscopy in the initial study period .
inagaki et al , in a retrospective study , reported a 95% overall success rate for tplp , including both dismembered and non - dismembered pyeloplasty .
soulie et al reported an 88.9% success rate for rplp , but the main drawback of the study was assessment of success based on excretory urography .
abuanz et al , in a retrospective nonrandomized study , reported an 87% success rate for rplp versus 82% for tplp ( 85% overall success rate ) .
the drawbacks of their study were the involvement of multiple surgeons , comparatively small sample size , and difficulty in controlling follow - up in some patients .
the explanation for the comparatively lower success rate ( 85% ) in this study was the comparatively longer follow - up period ( 48.93  38.94 months ) , which might have altered the long - term success of the procedures .
shoma et al , in a prospective randomized comparison between tplp and rplp , showed 95% and 90% success rates , respectively , with mean follow - up periods of 23 months and 20 months , respectively .
eden et al , in a prospective study , reported a 97.5% success rate for rplp with a mean follow - up period of 19.7 months .
janetschek et al , in an interesting study , reported a 98.5% success rate for fenger - plasties at long - term follow - up . in our study
the success rate was 96.4% for tplp versus 96.6% for rplp with a mean follow - up period of 30.75  4.85 months versus 30.99  5.59 months ( p < .88 ) .
follow - up in this study was performed with ivu and dtpa scans at 3 months and then by dtpa scans every 12 months .
our study is the first prospective randomized study that included a good sample size with long - term follow - up .
all procedures were performed by a single urologist using 3 ports to allow a fair comparison of all postoperative parameters including pain .
the vas scoring was performed on the first and second postoperative days by a person who was blinded to the procedure type , and the complications were recorded using the modified clavien grading system .
although the operative time is significantly higher for rplp , tplp is significantly associated with postoperative pain , requirement for tramadol , hospital stay , and ileus in comparison with rplp .
 background and objectives : to compare laparoscopic transperitoneal versus retroperitoneoscopic pyeloplasty for primary ureteropelvic junction obstruction in a prospective randomized manner and assess overall results with long - term follow-up.methods:in this prospective study , from 2008 to 2012 , 112 cases of primary ureteropelvic junction obstruction were randomized in a 1:1 ratio into 2 groups . 
 group i included patients who underwent transperitoneal laparoscopic pyeloplasty , and group ii consisted of patients who underwent retroperitoneoscopic laparoscopic pyeloplasty . 
 demographic and clinical characteristics and postoperative and operative data were collected and analyzed . 
 the statistical analysis was performed with the fisher exact test , 2 test , and mann - whitney u test for independent groups , and p < .05 was considered statistically significant.results:the total operative time and intracorporeal suturing time were significantly higher in group ii than in group i ( p < .001 ) . the visual analog scale score for pain on postoperative day 1 and the requirement for tramadol were significantly higher in group i than in group ii ( p = .004 ) . the hospital stay and the rate of temporary ileus were significantly greater ( p < .036 and p < .02 , respectively ) in group i than in group ii . 
 the success rate of transperitoneal laparoscopic pyeloplasty versus retroperitoneoscopic laparoscopic pyeloplasty was 96.4% versus 96.6% with a mean follow - up period of 30.75  4.85 months versus 30.99  5.59 months ( p < .88).conclusion : transperitoneal laparoscopic pyeloplasty is associated with significantly greater postoperative pain , a higher tramadol dose , a higher rate of ileus , and a longer hospital stay in comparison with retroperitoneoscopic laparoscopic pyeloplasty . 
 although the operative time for retroperitoneoscopic laparoscopic pyeloplasty is significantly longer , the success rate remains the same for both procedures . 
INTRODUCTION
MATERIALS AND METHODS
Transperitoneal Laparoscopic Pyeloplasty
Retroperitoneoscopic Laparoscopic Pyeloplasty
Postoperative Care and Follow-Up
Statistical Analysis
RESULTS
DISCUSSION
CONCLUSION