document: the role of endoscopic injection of dextranomer / hyaluronic acid copolymer ( dx / ha ) has expanded , as an alternative to open surgery , to a treatment option for observation protocols using prophylactic antibiotics . 
   deflux has been fda approved since 2001 as a treatment option for grade 24 vesicoureteral reflux ( vur ) in single systems with no accompanying urological malformations in children above one year of age . 
   the operative ease of technique , short procedure , and recovery time as well as repeatability of injections have popularized the technique with surgeons and parents alike . 
   reports of expanded use to patients of all ages and grades of vur even in the presence of duplication , ureterocele , or other lower tract anomalies are published worldwide [ 1 , 2 ] .   in a statement of the aua board of directors from october 2007 
   , it was determined that :  it is the current position of the american urological association that endoscopic injection of the dextranomer / hyaluronic compound deflux is an option in the management of pediatric vesicoureteral reflux ( vur )  [ 3 , 4 ] . 
   the initial success rate was quoted as 68%   and is still mentioned on the current website   of the manufacturing company ( q - med , scandinavia inc ) . in the meantime , the original subureteric injection technique ( sting ) has evolved to the intraureteric injection technique introduced by the atlanta group . using this hydrodistention - implantation technique ( hit ) , the authors reported success rates of 89% . 
   however , the reported worldwide success rates differ considerably ( 55%89% [ 7 , 8 ] ) . unpublished data from our institution show an overall radiographic success rate of 75% for patients and 84% for renal units after the first injection . 
   although the success rates continuously improve , the numbers of most institutions still differ significantly from the traditional 98% for open reimplants . since up to 25% of patients will have remaining vur after dx / ha injection , we still perform voiding cystograms 2 months after surgery . 
   positional instillation of contrast ( pic ) cystography was developed to detect occult vur in patients with recurrent urinary tract infections ( uti ) after a negative standard voiding cystogram . 
   it has a higher sensitivity than standard voiding cystogram ( vcug ) and can detect occult vur . 
   parents can be advised that in case of a positive pic , dx / ha injection can be performed during the same anesthesia . in the current study , we compared two different pic techniques and evaluated two different scenarios : first , whether pic cystography or high - pressure cystograms were useful to detect de novo contralateral vur in the case of preoperative unilateral vur and second , whether pic cystography , when performed intraoperatively immediately after dx / ha injection , can predict a successful surgical outcome by correlating the results with a standard 2-month postprocedure vcug . 
   a retrospective chart review was performed on all intraoperative cystograms performed at the time of dx / ha injections at our institution from 20052007 . 
   dx / ha injections were performed for all grades of vur and included complex cases such as duplicated systems . in case of preoperative unilateral reflux , a pic cystogram was performed on the contralateral unaffected side before dx / ha injection . if positive , bilateral injection took place . 
   the injections were done using the hit technique as described by kirsch et al . . 
   dx / ha was injected until a sufficient mound and good ureteral coaptation was observed . at this point 
   the outflow portion of the 10 french off set cystoscope ( wolf , germany ) was placed at the bladder neck filling the bladder with contrast material ( cystografin ) to 100  cm water pressure until voiding occurred around the cystoscope ensuring complete bladder filling . 
   the second group underwent standard pic cystography   with the outflow portion of the cystoscope directed at the ureteral orifice at a 100  cm water pressure for 5 seconds ( figure 2 ) . 
   radiographic views for both tests were performed in anterior - posterior and lateral as well as upper tract views . 
   the intraoperative cystogram was noted to be positive if any grade of vur was present ( figure 3 ) . in cases of a positive study on the contralateral side or for remaining vur after injection , 
   the patients were left on prophylactic antibiotics and followed up at 4 weeks postoperatively with an ultrasound and 2 months postoperatively with a vcug . 
   the correlations of the intra- and postoperative study as well as the detection of de novo vur were noted . 
   altogether 116 patients and 177 renal units ( ru ) were treated and available for evaluation . out of the 116 patients , 
   new contralateral vur ( de novo ) for the 34 preoperative unilateral refluxing patients was found intraoperatively in 27 ru ( figure 4(c ) ) . 
   the high - pressure intraoperative cystogram ( group 1 ) was performed in 86 rus and the standard pic ( group 2 ) in 91 rus . 
   there was no statistically significant difference between groups 1 and 2 for the detection of de novo vur ( figure 4(b ) ) .   for both groups , 
   only 5 ru were found to have remaining vur intraoperatively after dx / ha injection ( 2 in group 1 and 3 in group 2 ) . 
   postoperative pain management , if necessary , consisted of ibuprofen or acetaminophen according to parental preference . in all patients , 
   the postoperative us at four weeks were negative for hydronephrosis or any other new abnormality . 
   the dx / ha deposits were seen in the bladder in all cases . at 2 months 
   postoperative standard vcug detected 20 ru ( 23% ) to be positive for vur in group 1 and 16 ru ( 18% ) positive for vur in group 2 . 
   altogether 36 ru were positive , for an allover success rate of 80% for ru and 75% for patients ( figure 4(a ) ) . 
   the grade of vur , age and gender of patient as well as amount of deflux injected did not influence the result . 
   vesicoureteral reflux remains a common disease , and especially for lower grades the prospect of spontaneous resolution is good . 
   but , the data on the value of daily prophylactic antibiotics remain controversial , and most parents are concerned about their long - term use . 
   the discussion becomes evident by the current multi - institutional nih - funded rivur study , which aims to evaluate the role of prophylactic antibiotic in vur . 
   in addition to prolonged antibiotic use , parents and patients alike dread the yearly necessary voiding cystogram to check for resolution . 
   therefore , to avoid the daily antibiotics and the yearly vcug , many parents consider surgical treatment options . 
   the endoscopic injection of dx / ha is an attractive management alternative for parents . when presenting the surgical options , all parents are enthusiastic about the minimal invasive nature of the procedure with low complication possibilities and fast recovery times . 
   however , the 20%25% lower success rate of the endoscopic procedure in comparison to the open surgery is a concern . 
   although dx / ha can be reinjected , it requires further testing , anesthesia , and time spent away from school or work . 
   therefore , it would be highly desirable to develop a method to check the success of the deflux injection intraoperatively . 
   pic cystography is used to detect occult vur in patients with a negative standard voiding study who suffer from recurrent utis . according to rubenstein 
   , the procedure is a 100% sensitive and 91% specific in identifying vur and can , therefore , detect occult vur . 
   recently confirmed the findings in 5 patients . in a study on 39 patients with febrile utis and negative voiding studies from 4 different institutions , 
   pic cystograms were performed and vur identified in 82% of these patients . additionally , the authors noted that orifices that were patulous , laterally displaced , or positive for hydrodistention were much more likely to be positive for vur than normal orifices . 
   also performed intraoperative pic cystograms and found that 23% of patients had a positive , postoperative vcug despite a negative intraoperative pic study , and palmer confirmed these results . 
   the authors concluded that pic cystography was not useful to raise the success rate of deflux injection .   in the current study , we used two different cystogram techniques : the standard pic study and a high - pressure cystogram , filling the bladder until irrigation fluid leaked around the cystoscope . 
   even with this aggressive cystogram technique only an 80% correlation between a negative intraoperative cystogram and postoperative cystogram was achieved . 
   the success rate of 75% for patients and 80% for ru could not be improved . 
   a relative wound edema might increase the coaptation of the ureteral orifice , temporarily giving a negative intraoperative study result . 
   other possibilities include decrease in the size of the injected dx / ha deposit over time , also thought to be responsible for long - term failure after dx / ha injection . 
   this phenomenon has been noted during cystoscopy at the time of the planned second injection of deflux after initial failure . 
   the dx / ha deposits tend to migrate medially and toward the bladder neck causing long - term failure of injection . 
   elmore et al . reported the onset of new contralateral vur after dx / ha implantation in approximately 13% of 126 patients with preoperatively unilateral vur . in the current study , 
   twenty seven of these 34 patients demonstrated a positive pic cystography intraoperatively and were successfully injected with dx / ha . 
   none of these de novo detected refluxing units were positive for vur in the postoperative cystograms . 
   a negative intraoperative cystogram correlates with the postoperative vcug in only 80% . considering that the success rates of dx / ha injections are commonly between 7580% 
   , the addition of intraoperative cystograms can not replace postoperative studies . in patients treated with unilateral vur 
   , pic cystography can detect occult reflux and prevent postoperative contralateral new onset of vur .
summary: the endoscopic injection of dx / ha in the management of vesicoureteral reflux ( vur ) has become an accepted alternative to open surgery . in the current study we evaluated the value of cystography to detect de novo contralateral vur in unilateral cases of vur at the time of dx / ha injection and correlated the findings of immediate post - dx / ha injection cystography during the same anesthesia to 2-month postoperative vcug to evaluate its ability to predict successful surgical outcomes . the current study aimed to evaluate whether an intraoperatively performed cystogram could replace postoperative studies . but 
   a negative intraoperative cystogram correlates with the postoperative study in only 80% . considering the 7580% success rate of dx / ha implantation 
   , the addition of intraoperative cystograms can not replace postoperative studies . in patients treated with unilateral vur 
   , pic cystography can detect occult vur and prevent postoperative contralateral new onset of vur .