title: Clinical effectiveness of new stent design: randomized single-blind comparison of tail and double-pigtail stents.
abstract: OBJECTIVE
  Stent morbidity appears to be secondary to lower urinary tract irritation. In an effort to decrease stent morbidity, a "one size fits all" Tail stent (Microvasive [Boston Scientific] Natick, MA) was developed with a 7F proximal pigtail and 7F shaft which tapers to a lumenless straight 3F tail.
  
  
  METHODS
  We randomized 60 patients in a single-blind fashion to a 7F tail stent or 7F double-pigtail Percuflex stent. Patients were evaluated at the time of stent removal and 2 weeks later with a standardized questionnaire assessing: irritative lower tract symptoms individually and on a total scale of 0 (no symptoms) to 30 (worst symptoms), obstructive lower tract symptoms (on a total scale of 0-20), and upper tract irritative symptoms (on a total scale of 0-10).
  
  
  RESULTS
  Patient age, weight, and height were similar in the two groups. Complications, including fever, urinary tract infections, emergency room visits, and the need for antispasmodics and pain medication, also demonstrated no significant difference. At the time of stent removal, patients who received a tail stent had significantly less urinary frequency and a statistically significant (21%) decrease in overall irritative voiding symptoms (12.2 v 15.4; p = 0.048). Two weeks after stent removal, the total irritative voiding symptoms was markedly decreased in both groups (7.1 in the Tail v 5.3 in the double-pigtail group; p = 0.15). Obstructive bladder and flank symptoms were not significantly different in the two stent groups, either at the time of stent removal or at 2 weeks after removal.
  
  
  CONCLUSIONS
  In this randomized, single-blind study, the 7F Tail stent produced significantly less irritative symptoms than did the standard 7F double-pigtail stent. Obstructive symptoms tended to be less with the new stent, while flank symptoms were similar.
authors.affiliation: Division of Urology, Washington University, St. Louis, Missouri, USA. mdunn@ccnt.hsc.usc.edu
authors.forename: M D
authors.initials: MD
authors.lastname: Dunn
authors.forename: A J
authors.initials: AJ
authors.lastname: Portis
authors.forename: S A
authors.initials: SA
authors.lastname: Kahn
authors.forename: Y
authors.initials: Y
authors.lastname: Yan
authors.forename: A L
authors.initials: AL
authors.lastname: Shalhav
authors.forename: A M
authors.initials: AM
authors.lastname: Elbahnasy
authors.forename: E
authors.initials: E
authors.lastname: Bercowsky
authors.forename: D M
authors.initials: DM
authors.lastname: Hoenig
authors.forename: J S
authors.initials: JS
authors.lastname: Wolf
authors.forename: E M
authors.initials: EM
authors.lastname: McDougall
authors.forename: R V
authors.initials: RV
authors.lastname: Clayman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016037:Single-Blind Method; D015607:Stents / Q000009:adverse effects / Q000592:standards*; D014555:Urination Disorders / Q000209:etiology; D014567:Urography; D014570:Urologic Diseases / Q000209:etiology