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recurrent urinary tract infections ( uti ) , renal scarring , and the subsequent end - stage renal disease can be life threatening in these children . the main goal of treatment of vur is to prevent further episodes of uti and to avoid progressive renal scarring .
open surgical reimplantation can be attempted intravesical , extravesical , or a combined intra- and extra - vesical approach .
various authors have reported an increased incidence of postoperative bladder spasms , hematuria , and prolonged hospital stay with intravesical repairs .
the purpose of this article is to assess the outcomes of the extravesical ureteral reimplantation ( evr ) of modified gregoir lich technique and intravesical cohen 's ureteral reimplantation ( cur ) .
between 2003 and 2014 , children diagnosed with primary vur and undergoing ureteric reimplantation at our institution were evaluated for inclusion in this study .
patients with grade 12 vur , who were conservatively managed with antimicrobial prophylaxis and were not included .
those with higher grade of reflux were initially conservatively managed , but those who developed recurrent breakthrough utis / worsening of scars were intervened surgically .
those with secondary vur ( posterior urethral valves , neurogenic bladder , or bowel bladder dysfunction ) , associated anomalies such as ureteroceles , duplex systems , and ectopic ureters were excluded from our study .
those patients who did not have a follow - up evaluation or who did not turn up for follow - up were also excluded from our study . among the remaining patients with primary vur , evr was performed in group 1 , whereas cur in group 2 modified nerve sparing evr was performed in children younger than 2 years with bilateral vur , as gaining adequate transtrigonal tunnel by a cur would have been difficult in this cohort ( group 1a ) and in those with unilateral vur ( group 1b ; the ureteric orifices would be placed one over the other with cur in unilateral reflux , and this may cause confusion in instrumentation of the ureteric orifices later in life , if needed ) .
cur ( n = 67 ) was performed in children older than 2 years with bilateral vur [ figure 1 ] .
( a ) unilateral grade 4 vesicoureteral reflux in a 15-month - old child with a small bladder capacity , a typical case for extravesical reimplantation ; ( b ) bilateral grade 45 vesicoureteral reflux in a child older than 2 years with a good bladder size , a typical case for cohen 's reimplantation the following parameters were compared : length of the surgical procedure , average duration of stay in the hospital , postoperative bladder spasms ( excessive colic immediately before voiding / pericatheter leakage of urine / requirement of anticholinergics in addition to regular painkillers ) , significant postoperative hematuria ( for more than 72 h / required blood transfusions / clot retention ) .
long - term complications of the procedure such as persistent reflux and ureteral obstruction were also assessed .
postoperative evaluation included ultrasound + voiding cystourethrography ( vcug ) at 3 months and ultrasound + radionuclide imaging at 1 year postoperatively .
urodynamic assessment was not performed in the pre / postoperative period as a part of this study .
over a period of 11 years , between 2003 and 2014 , 750 children with vur were diagnosed and 188 ureteric reimplants were performed in our institution . after excluding 70 patients as per our exclusion criteria , a total of 118 patients were recruited into the study .
evr was performed in 51 patients ( group 1 ) , whereas cur in 67 ( group 2 ) .
the mean age at operation was 15 months for group 1 ( range 1024 months ) , whereas in group 2 , it was 36 months ( range 2460 months ) .
the median age for the two groups was 16 months and 40 months , respectively .
there was a female preponderance ( male : female = 43:75 ) . among group 1 ,
32 underwent bilateral evr ( group 1a ) , whereas the remaining underwent unilateral evr ( group 1b ) .
the mean duration of bilateral reimplantation was significantly less ( p = 0.0001 ) in group 1a ( n = 32 ; mean 104 min ; standard deviation [ sd ] 18 min ) compared to that in group 2 ( n = 67 ; mean 128 min ; sd 15 min ) .
the mean ( sd ) postoperative stay was significantly lower ( p = 0.0001 ) at 4.5 ( 1.5 ) days in group 1a compared to 6.5 ( 0.5 ) days in group 2 .
postoperative bladder spasms were significantly lower ( p = 0.03 ) at 10/32 in group 1a compared to 37/67 in group 2 .
postoperative hematuria was significantly lower ( p = 0.03 ) at 10/32 in group 1a compared to 31/67 in group 2 . on a repeat vcug at 3 months , persistent vur was noted in 4/51 ( 7.85% ) in group 1 compared to and 5/67 in group 2 ( 7.5% ) .
there was no significant difference between the groups and none of these patients developed recurrent febrile uti to warrant further intervention . at 1 year
follow , none of them had any evidence of ureteral obstruction on the radionuclide imaging .
group 1a ( bilateral extravesical reimplantation ) had significantly less duration of surgery , duration of stay , postoperative hematuria , and bladder spasms compared to group 2 ( bilateral cohen 's reimplantation )
the principal goal of any antireflux procedure is to restore the near normal antirefluxing mechanism of the ureterovesical junction .
the fact that there are a plenty of surgical techniques available for correction of vur means there is not a single foolproof technique that would suffice in the management of these patients .
the evr has generally been considered to be associated with reduced morbidity in comparison to cur .
the overall incidence of hematuria , bladder spasms , convalescence period , and the overall hospital stay have all been less with evr than with cur . in an attempt to further reduce the postoperative complications , zaontz et al . used a modified extravesical technique , where they created a submucosal tunnel , advanced the ureteral meatus and anchored it onto the trigone and closed it with a detrusor buttressing of the ureter , for which they coined the term  detrusorrhaphy .  they claimed a very minimal postoperative morbidity with such procedure .
ellsworth et al . compared the extravesical detrusorrhaphy with cur and claimed that the success rate is the same in both groups .
however , patients undergoing evr needed fewer pain medications and lesser anticholinergics to control bladder spasms .
they also noted that patients undergoing bilateral extravesical approach were associated with transient urinary retention .
wacksman et al . in 1992 performed evr in 132 patients and observed that evr and detrusorrhaphy are associated with a reduced postoperative morbidity and shortened hospital stay . in our study , the evr technique was found to be superior to that of cur , in terms of duration of surgery , postoperative hospital stay , incidence of hematuria and bladder spasms , and overall postoperative complications .
the difference in the age distribution between groups could be a pitfall in the current study design .
however , a nerve - sparing technique proposed by david reduced these complications , and in our study , none of the patient , who underwent bilateral evr developed retention .
in addition , a relatively straight access of ureter makes it easier for upper tract instrumentation , if needed at a later date . with the advent of laparoscopic and robotic techniques
further studies should through more light on the superiority of these techniques via a minimally invasive route .
it has the advantage of keeping a straight access to the upper tract for future instrumentation .
introduction : there are multiple techniques for surgical correction of vesicoureteral reflux ( vur ) . 
 we compared the outcomes of extravesical versus cohen 's reimplantation for vur in children.methods:records of all children ( n = 118 ) who underwent reimplantation for vur between 2003 and 2014 were analyzed ( male : female = 43:75 ) . children with secondary vur , duplication anomalies , and ectopic ureter were excluded from our study . 
 extravesical reimplantation ( evr ) was performed bilateral in 32 children ( group 1a ) and unilateral in 19 ( group 1b ) , while bilateral cohen 's reimplantation was performed in 67 ( group 2 ) . 
 parameters compared were length of the surgical procedure , average duration of stay in the hospital , postoperative bladder spasms , significant hematuria > 72 h , and long - term complications.results:the mean age at operation was 15 months in group 1 , and 36 months in group 2 . 
 the mean duration of surgery was significantly less ( p = 0.0001 ) in group 1a ( n = 32 ; mean 104 min ; standard deviation [ sd ] 18 min ) compared to group 2 ( n = 67 ; mean 128 min ; sd 15 min ) . 
 the mean ( sd ) postoperative stay was significantly lower ( p = 0.0001 ) at 4.5 ( 1.5 ) days in group 1a compared to 6.5 ( 0.5 ) days in group 2 . 
 postoperative bladder spasms were significantly lower ( p = 0.03 ) at 10/32 in group 1a compared to 37/67 in group 2 . 
 all patients responded well with anticholinergics . 
 postoperative hematuria and bladder spasms were significantly lower ( p = 0.03 ) in group 1a compared to group 2 . 
 there was no significant difference in persistent vur between group 1 and group 2 . at 1 year 
 follow , none of them had any evidence of ureteral obstruction.conclusions:evr has lower operative time , less postoperative discomfort and shorter hospital stay compared to cohen 's reimplantation . 
 both techniques are equally effective in treating reflux .