title: Retrospective comparison of internally and externally covered retrievable stent placement for patients with benign urethral strictures caused by traumatic injury.
abstract: OBJECTIVE
  The purpose of this article is to compare the clinical effectiveness and complications of externally and internally covered stents for the treatment of benign urethral strictures.
  
  
  METHODS
  From July 2002 to June 2010, 59 retrievable self-expandable polytetrafluoroethylene-covered nitinol stents were placed in 33 men with benign urethral strictures. These included 34 internally covered stents placed in 18 patients (group I) and 25 externally covered stents in 15 patients (group E). Stents were routinely removed 4 months after placement from patients who experienced no complications. Complications, duration of stent placement, removal techniques, and maintained patency rates were compared in the two groups.
  
  
  RESULTS
  Twenty-eight complications (82.4%) occurred in 15 patients in group I, whereas 12 complications (48%) occurred in six patients in group E (p=0.005). Three (16.7%) patients in group I and nine (60%) in group E had their stents electively removed without complications (p=0.010). Stent migration was more frequent in group I (47.1%) than in group E (24.0%). No tissue ingrowth was detected in group E, whereas six cases of tissue ingrowth occurred in group I (p=0.034). The standard technique was used more frequently in group E (70.8%). The median stent indwelling period was significantly shorter in group I than in group E (51.5 vs 114 days; p=0.34).
  
  
  CONCLUSIONS
  Despite their relatively high complication rates, externally covered stents are more effective with fewer complications than internally covered stents in the treatment of benign urethral strictures.
authors.affiliation: Department of Radiology and Research Institute of Radiology, 388-1, Poongnap 2-dong, Songpa-gu, Seoul 138-736, Republic of Korea.
authors.forename: Han Kyu
authors.initials: HK
authors.lastname: Na
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Song
authors.forename: Hyun Jin
authors.initials: HJ
authors.lastname: Yeo
authors.forename: Jung-Hoon
authors.initials: JH
authors.lastname: Park
authors.forename: Jin Hyoung
authors.initials: JH
authors.lastname: Kim
authors.forename: Hyungkeun
authors.initials: H
authors.lastname: Park
authors.forename: Choung-soo
authors.initials: CS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000497:Alloys; D016009:Chi-Square Distribution; D020099:Coated Materials, Biocompatible; D020878:Device Removal; D006801:Humans; D008297:Male; D008875:Middle Aged; D011138:Polytetrafluoroethylene; D011474:Prosthesis Design; D015641:Radiography, Interventional; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D015607:Stents / Q000009:adverse effects; D016896:Treatment Outcome; D014525:Urethral Stricture / Q000209:etiology* / Q000628:therapy*
chemical_list: D000497:Alloys; D020099:Coated Materials, Biocompatible; C013616:nitinol; D011138:Polytetrafluoroethylene