title: Recurrent traumatic urethral strictures near the external sphincter: treatment with a covered, retrievable, expandable nitinol stent--initial results.
abstract: OBJECTIVE
  To investigate the clinical effectiveness of a covered, retrievable, expandable nitinol stent in treating traumatic urethral strictures near the external sphincter.
  
  
  METHODS
  The stent was 10 mm in diameter when fully expanded and 40-50 mm long. To make it removable, two nylon drawstrings were attached to its lower inner margin. Twelve consecutive men (19-67 years; mean age, 47 years) with traumatic urethral strictures near the external sphincter that were refractory to endoscopic urethrotomy were treated. With fluoroscopic guidance, a stent was placed to completely bridge the external sphincter. The stent was electively removed with a retrieval hook wire 2 months after placement. Stent placement and removal were successful in all patients, with no procedural complications.
  
  
  RESULTS
  Mean maximum urine flow rate was 5 mL/sec (range, 3-7 mL/sec) before stent placement and 27 mL/sec (range, 16-40 mL/sec) at 1 week after placement. During the mean follow-up of 20 months (range, 2-37 months) after the first stent removal, strictures recurred in eight of 12 patients. For the eight patients with recurrence, a second stent was placed and 4 months later was removed from seven of the eight patients. During the mean follow-up of 18 months (range, 4-32 months) after the second stent removal, strictures recurred in two patients, in whom a third stent was placed and then removed 4 months later, with good results. Four (33%) of 12 patients, five (62%) of eight patients, and two (100%) of two patients were successfully treated with placement of the first stent, the second stent, and the third stent, respectively. In the remaining patient, the second stent remains in place.
  
  
  CONCLUSIONS
  Placement of a covered, retrievable, expandable nitinol stent seems to be effective in treating urethral strictures near the external sphincter and warrants further investigation.
authors.affiliation: Department of Diagnostic Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap-dong, Songpa-gu, Seoul 138-736, Korea. hysong@www.amc.seoul.kr
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Song
authors.forename: Hyungkeun
authors.initials: H
authors.lastname: Park
authors.forename: Tae-Suk
authors.initials: TS
authors.lastname: Suh
authors.forename: Gi-Young
authors.initials: GY
authors.lastname: Ko
authors.forename: Tae-Hyung
authors.initials: TH
authors.lastname: Kim
authors.forename: Eun-Sang
authors.initials: ES
authors.lastname: Kim
authors.forename: Taehan
authors.initials: T
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000497:Alloys; D020878:Device Removal; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012008:Recurrence; D015607:Stents; D016896:Treatment Outcome; D014521:Urethra / Q000000981:diagnostic imaging / Q000293:injuries*; D014525:Urethral Stricture / Q000000981:diagnostic imaging / Q000601:surgery*
chemical_list: D000497:Alloys; C013616:nitinol