title: Posttuberculosis tracheobronchial stenosis: use of CT to optimize the time of silicone stent removal.
abstract: OBJECTIVE
  To evaluate whether air pockets (tracheobronchial air columns in the space between the outer surface of the stent and the adjacent airway wall) discernible at computed tomography (CT) can help optimize the time of stent removal in patients with posttuberculosis tracheobronchial stenosis (PTTS).
  
  
  METHODS
  The study was approved by the institutional review board, and informed consent was obtained from all patients. Data from 41 patients (five men, 36 women) with a median age of 39 years (range, 21-64 years) who underwent silicone stent placement owing to PTTS, followed by CT and stent removal 6-12 months after clinical stabilization, were investigated retrospectively. Two radiologists determined whether the extent of air pockets on CT scans was associated with clinical success, which was defined as maintenance of a prosthesis-free airway for more than 2 years after stent removal. Radiologic features were compared for outcome by using a Wilcoxon two-sample test or Fisher exact test.
  
  
  RESULTS
  Stents were removed successfully in 31 patients (76%). Air pockets longer than 1 cm or longer than 2 cm were associated with successful stent removal (P = .04 and P = .006, respectively). The sensitivity and specificity of air pocket length in the prediction of successful stent removal were 84% and 50%, respectively, for air pockets longer than 1 cm and 68% and 70% for air pockets longer than 2 cm.
  
  
  CONCLUSIONS
  The extent of air pockets at chest CT shows correlation with the success of stent removal, indicates regression of stenosis, and may help guide the optimal time for stent removal.
authors.affiliation: Department of Medicine, Sungkyunkwan University School of Medicine, Gangnam-gu, Seoul, Korea.
authors.forename: Akash
authors.initials: A
authors.lastname: Verma
authors.forename: Hye Yun
authors.initials: HY
authors.lastname: Park
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Lim
authors.forename: Sang-Won
authors.initials: SW
authors.lastname: Um
authors.forename: Won-Jung
authors.initials: WJ
authors.lastname: Koh
authors.forename: Gee Young
authors.initials: GY
authors.lastname: Suh
authors.forename: Man Pyo
authors.initials: MP
authors.lastname: Chung
authors.forename: O Jung
authors.initials: OJ
authors.lastname: Kwon
authors.forename: Hojoong
authors.initials: H
authors.lastname: Kim
mesh_terms: D000328:Adult; D001982:Bronchial Diseases / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy*; D020878:Device Removal; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012828:Silicones; D018709:Statistics, Nonparametric; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014135:Tracheal Stenosis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy*; D014397:Tuberculosis, Pulmonary / Q000150:complications*
chemical_list: D012828:Silicones