title: Conventional high-resolution CT versus helical high-resolution MDCT in the detection of bronchiectasis.
abstract: OBJECTIVE
  The purpose of this study was to compare conventional high-resolution CT (HRCT) with helical 16-MDCT in the detection of bronchiectasis.
  
  
  METHODS
  We retrospectively evaluated 80 patients including 61 with bronchiectasis (mean age, 64 years; range, 22-87 years) and a control group of 19 patients with normal MDCT of the chest. Two sets of images were blindly, randomly analyzed by two observers: contiguous 1-mm slices (MDCT set) and 1-mm slices every 10 mm (HRCT set) derived from the MDCT set. Images were scored independently for presence, extent, and severity of bronchiectasis, followed by a consensus interpretation. Kappa analysis assessed inter- and intraobserver agreement. MDCT was the radiologic gold standard.
  
  
  RESULTS
  Of the 61 patients with bronchiectasis diagnosed with MDCT, 56 (92%) were positive for bronchiectasis on conventional HRCT. Seven patients had positive MDCT scans only, and two patients had positive HRCT scans only. Of 479 lobes, 59 were positive for bronchiectasis on MDCT and negative on HRCT, and 19 lobes were positive for bronchiectasis on HRCT and negative on MDCT (p < 0.0001). MDCT showed 25 more lobes with cylindric, 11 more lobes with varicose, and four more lobes with cystic bronchiectasis than did HRCT. Sensitivity, specificity, and positive and negative predictive values of HRCT in detecting bronchiectasis were 71%, 93%, 88%, and 81%, respectively. Interobserver agreement for presence, extent, and severity of bronchiectasis ranged from moderate to good for MDCT (kappa values, 0.64, 0.5, and 0.48, respectively) and poor to good for HRCT (kappa values, 0.65, 0.46, and 0.25, respectively).
  
  
  CONCLUSIONS
  Contiguous helical 16-MDCT with 1-mm collimation is superior to HRCT at 10-mm intervals in showing the presence and extent of bronchiectasis.
authors.affiliation: Department of Radiology, Vancouver General Hospital, 855 W. 12th Ave., Vancouver, British Columbia, Canada V6K 1R4.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Dodd
authors.forename: Carolina A
authors.initials: CA
authors.lastname: Souza
authors.forename: Nestor L
authors.initials: NL
authors.lastname: Müller
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001987:Bronchiectasis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D036542:Tomography, Spiral Computed; D014057:Tomography, X-Ray Computed / Q000379:methods*