title: Efficacy of hydrodistention implantation technique in treating high-grade vesicoureteral reflux.
abstract: OBJECTIVE
  In the endoscopic treatment of vesicoureteral reflux, the relatively high rate of success, the simplicity of the procedure, high patient compliance, and a lack of complications has led to the increased development of injection materials and techniques. We report a method of identifying and maintaining a clear visual field during ureteral and bladder submucosal wall injection of a dextranomer/hyaluronic acid copolymer (Deflux, Oceana, Therapeutics Inc.) by use of the hydrodistention implantation technique (HIT) with the aid of temporary ureteral catheter insertion.
  
  
  METHODS
  We prospectively reviewed patients with grade IV or V reflux who received an endoscopic injection of Deflux. Reflux grade was evaluated before and after treatment (3 months) by use of voiding cystourethrograms. Conventional sub-trigonal injection (STING) was performed with injection of Deflux underneath the bladder mucosa at the 6 o'clock position. HIT was performed either with hydrodistention or with guidewire insertion. These techniques increase visualization of the intramural portion of the distal ureteral wall. Patients with treatment failures were offered reinjection up to three times.
  
  
  RESULTS
  Sixty-three patients completed endoscopic injection and follow-up of 3 months. The overall resolution rate for conventional STING was 58%, i.e., 67% for grade IV and 43% for grade V. The overall resolution rate for HIT was 80%, i.e., 93% for grade IV and 66% for grade V. The modified methods showed higher resolution rates for overall cure owing to the success in patients with grade IV reflux (p=0.026). Although the success of grade V treatment was higher with the modified method, the success rate was not statistically significant (p=0.27).
  
  
  CONCLUSIONS
  HIT with the use of either hydrodistention or a guidewire to aid in visualization of the intramural portion of the distal ureter is an effective treatment for high-grade vesico-ureteral reflux.
authors.affiliation: Department of Urology, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Ji Sung
authors.initials: JS
authors.lastname: Shim
authors.forename: Jin Wook
authors.initials: JW
authors.lastname: Kim
authors.forename: Mi Mi
authors.initials: MM
authors.lastname: Oh
authors.forename: Du Geon
authors.initials: du G
authors.lastname: Moon