title: Ureteral double-J wire stent effectiveness after endopyelotomy: an animal model study.
abstract: OBJECTIVE
  The aim of this experimental study was to assess the possibility of decreasing the size of the ureteral stents used after an endopyelotomy. To this end, an experimental study was performed which compared a ureteral double-J wire stent versus a standard 7F ureteral stent after endopyelotomy.
  
  
  METHODS
  Twenty healthy female pigs were randomly divided into 2 groups: group I (double pigtail ureteral stent 7F) and group II (lumenless ureteral double-J wire stent, Zebrastent™, 0.035 inches in diameter). Percutaneous, endoluminal ultrasonographic and fluoroscopic studies were analyzed during the 3 different phases of the study. The first phase included premodel documentation of normal urinary tracts and laparoscopic ureteropelvic junction (UPJ) obstruction induction. During the second phase, 6 weeks later, diagnosis and endopyelotomy were carried out. Sixteen weeks after the obstruction treatment, follow-up imaging studies and postmortem evaluations of all animals were performed.
  
  
  RESULTS
  After the sonographic and fluoroscopic assessments, we determined the success rate for each group: 80% for group I and 90% for group II. No significant statistical differences were evident in the evolution of the diameter of the UPJ between groups. Better healing of the UPJ and a lower level of retroperitoneal repercussions were seen in group II.
  
  
  CONCLUSIONS
  The ureteral double-J wire stent (Zebrastent) has been shown to be highly effective after endopyelotomy. This means that it is possible to reduce the size of ureteral stents after endopyelotomy with the advantages that this entails. Double-J ureteral stents probably act as a scaffold rather than a mold.
authors.affiliation: Department of Endoscopy-Endourology, Jesús Usón Minimally Invasive Surgery Center, Cáceres, Spain. fsoria @ ccmijesususon.com
authors.forename: Federico
authors.initials: F
authors.lastname: Soria
authors.forename: M Inmaculada
authors.initials: MI
authors.lastname: Delgado
authors.forename: Luis Ángel
authors.initials: LÁ
authors.lastname: Rioja
authors.forename: Miguel
authors.initials: M
authors.lastname: Blas
authors.forename: Manuel
authors.initials: M
authors.lastname: Pamplona
authors.forename: Esther
authors.initials: E
authors.lastname: Durán
authors.forename: Jesús
authors.initials: J
authors.lastname: Usón
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Sánchez
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D005471:Fluoroscopy / Q000379:methods; D007682:Kidney Pelvis / Q000473:pathology; D010535:Laparoscopy / Q000379:methods*; D015607:Stents; D013552:Swine; D016896:Treatment Outcome; D014463:Ultrasonography / Q000379:methods; D014513:Ureter / Q000601:surgery*; D014551:Urinary Tract / Q000473:pathology; D014567:Urography / Q000379:methods; D013520:Urologic Surgical Procedures / Q000295:instrumentation* / Q000379:methods*; D014572:Urology / Q000379:methods*