title: A new antireflux technique: mucosal flap barrier.
abstract: BACKGROUND
  In this study, our aim was to evaluate the effectiveness of the mucosal flap barrier (MFB) upon the incompetent ureteral orifice of an experimentally produced rabbit reflux model. The rabbit reflux model was done in the first stage of the study. This method is a new and original procedure which is different from Bischoff's and Witherington's osteoplasty techniques.
  
  
  METHODS
  We performed the mucosal flap procedure in eight 2-2.5 kg male New Zealand rabbits with experimentally produced refluxing ureters. The first stage of our study was to create refluxing ureters. Due to the upward and inward 'J' fishhook course of the intravesical ureter of rabbits, we performed two deep 12- and 4-o'clock incisions by suturing the edges of the intravesical ureter apart with catgut sutures. Additionally, to stop the tilting action of the trigonum during micturition, we performed two parallel incisions between the ureteral meatus. These parallel incisions were the authors' modifications for the rabbit reflux model and which gives long-lasting reflux for the rabbit. We checked the reflux at the end of the 3rd month and performed our new MFB antireflux procedure. This mucosal flap made a cover on the incompetent ureteral orifice. This technique is completely different from the osteoplasty techniques described by Bischoff and Witherington.
  
  
  RESULTS
  Four months after the MFB application, we performed intravenous urography, cystometry and cinefluorography. There was no obstruction or reflux. Two rabbits were sacrificed at the 4th month. Both flaps were fully intact without any fixation at the medial side causing obstruction. At present, 3 rabbits are still alive. We did cinefluorography and cystometry at the 15th month and there was no obstruction or reflux. We are trying to keep them alive till the end of their natural lifespan.
  
  
  CONCLUSIONS
  During the formation of the rabbit reflux model, we observed that spontaneous reflux even at high intravesical pressures did not have high percentages as previously mentioned in the literature. But it is possible and enough to produce an experimental reflux model by using meatotomy and interureteric incisions. Moreover, in rabbits with vesicoureteral regurgitation produced by ureteral meatotomy and interureteral incisions, reflux can be eliminated the MFB procedure. This method is an easy procedure for small bladders or dilated ureters after any kind of open reimplantation applications and it could be used by pneumovesical applications in the future.
authors.affiliation: Department of Urology, Gulhane Military Medical Academy, School of Medicine, Ankara, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Dayanc
authors.forename: Lutfu
authors.initials: L
authors.lastname: Tahmaz
authors.forename: Selahattin
authors.initials: S
authors.lastname: Bedir
authors.forename: Ali
authors.initials: A
authors.lastname: Avci
mesh_terms: D000818:Animals; D009092:Mucous Membrane; D011817:Rabbits; D013524:Surgical Flaps; D013520:Urologic Surgical Procedures / Q000379:methods; D014718:Vesico-Ureteral Reflux / Q000601:surgery*