title: Preliminary Assessment of a New Antireflux Ureteral Stent Design in Swine Model.
abstract: OBJECTIVE
  To assess a new antireflux ureteral stent in animal model. The design expects to reduce morbidity associated with JJ ureteral stents.
  
  
  METHODS
  Twelve pigs were used in this study. The study began with a nephrosonographic assessment and excretory urography. Afterward, measurement of the internal diameter of both ureteropelvic junctions (UPJ) by retrograde ureteropyelography was performed. A 3 Fr (ARS group) antireflux ureteral stent was placed in the right kidney and a JJ 4 Fr (JJ group) stent was placed in the left. Follow-ups were performed at 3-6 weeks; both stents were removed at 6 weeks. The final follow-up was completed at 5 months. This includes the above-mentioned diagnostic methods and an anatomopathological study.
  
  
  RESULTS
  There were no significant differences in UPJ diameter evolution between groups. During renal damage assessment, significant differences at 3 and 6 weeks were found, renal dilation being larger in JJ group. The JJ group shows a higher degree of vesicoureteral reflux at 3 and 6 weeks. After assessment of ureteral orifice, significant differences between groups were found at 3 weeks, 6 weeks, and 5 months, damage being more severe in the JJ group. After anatomopathological assessment, no statistical significance at UPJ was observed. However, statistical significance was found at ureterovesical junction, damage being more severe in the JJ group.
  
  
  CONCLUSIONS
  The antireflux ureteral stent design dilates the upper urinary tract without affecting ureterovesical junction, and consequently reduces morbidity associated with JJ ureteral stents. Therefore, its patient tolerance will possibly be better than that to existent designs.
authors.affiliation: Endoscopy Department, Minimally Invasive Surgery Centre Jesús Uson, Caceres, Spain. Electronic address: fsoria@ccmijesususon.com.
authors.forename: Federico
authors.initials: F
authors.lastname: Soria
authors.affiliation: Endoscopy Department, Minimally Invasive Surgery Centre Jesús Uson, Caceres, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Morcillo
authors.affiliation: Urology Department, University Hospital Clinico San Carlos, Madrid, Spain.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Serrano
authors.affiliation: Urology Department, University Hospital Miguel Servet, Zaragoza, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Rioja
authors.affiliation: Endourology Section, University Hospital La Fe, Valencia, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Budia
authors.affiliation: Urology Department, University Hospital Clinico San Carlos, Madrid, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Moreno
authors.affiliation: Endoscopy Department, Minimally Invasive Surgery Centre Jesús Uson, Caceres, Spain.
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Sanchez-Margallo
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D011474:Prosthesis Design; D015607:Stents; D013552:Swine; D014513:Ureter / Q000601:surgery*; D014718:Vesico-Ureteral Reflux / Q000517:prevention & control*