title: Assessment of stricture formation with the ureteral access sheath.
abstract: OBJECTIVE
  To analyze the long-term incidence of ureteral stricture formation in a series of patients in whom a new-generation ureteral access sheath was used. A new generation of ureteral access sheaths has been developed to facilitate ureteroscopic procedures. However, some have questioned their safety and whether the device might cause significant ureteral trauma.
  
  
  METHODS
  Between September 1999 and July 2001, 150 consecutive ureteroscopic procedures with adjunctive use of an access sheath were performed. A retrospective chart review to April 2002 was done. Of the 150 patients, 130 underwent ureteroscopy for ureteral stones. Patients who underwent endoureterotomy or treatment of transitional cell carcinoma were excluded from this analysis. Sixty-two patients had follow-up greater than 3 months and were included in the analysis. Overall, 71 ureteroscopic procedures were performed, with 9 patients undergoing multiple procedures. Ninety-two percent of the patients had pathologic findings above the iliac vessels. The average patient age was 45.3 years (range 17 to 76), and 70% and 30% of the patients were male and female, respectively. The mean clinical follow-up was 332 days (range 95 to 821), and follow-up imaging was performed within 3 months after ureteroscopy in all patients.
  
  
  RESULTS
  The 10/12F access sheath was used in 8 ureteroscopic procedures (11.2%), the 12/14F access sheath in 56 (78.9%), and the 14/16F access sheath in 7 (9.8%). One stricture was identified on follow-up imaging of 71 procedures performed, for an incidence of 1.4%. The patient developed the stricture at the ureteropelvic junction after multiple ureteroscopic procedures to manage recurrent struvite calculi. The access sheath did not appear to be a contributing factor.
  
  
  CONCLUSIONS
  The results of our series indicate that the ureteral access sheath is safe and beneficial for routine use to facilitate flexible ureteroscopy. However, awareness of the potential ischemic effects with the use of unnecessarily large sheaths for long periods in patients at risk of ischemic injury should be considered. We advocate the routine use of the device for most flexible ureteroscopic procedures proximal to the iliac vessels.
authors.affiliation: Comprehensive Kidney Stone Center, Division of Urology, Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: Fernando C
authors.initials: FC
authors.lastname: Delvecchio
authors.forename: Brian K
authors.initials: BK
authors.lastname: Auge
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Brizuela
authors.forename: Alon Z
authors.initials: AZ
authors.lastname: Weizer
authors.forename: Ari D
authors.initials: AD
authors.lastname: Silverstein
authors.forename: Costas D
authors.initials: CD
authors.lastname: Lallas
authors.forename: Paul K
authors.initials: PK
authors.lastname: Pietrow
authors.forename: David M
authors.initials: DM
authors.lastname: Albala
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Preminger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D017602:Lithotripsy, Laser / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013525:Surgical Instruments / Q000009:adverse effects; D016896:Treatment Outcome; D014513:Ureter / Q000293:injuries; D014514:Ureteral Calculi / Q000601:surgery / Q000628:therapy*; D014517:Ureteral Obstruction / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D020709:Ureteroscopes / Q000009:adverse effects*; D018666:Ureteroscopy / Q000009:adverse effects* / Q000379:methods