title: Detectability of various sizes of honeycombing cysts in an inflated and fixed lung specimen: the effect of CT section thickness.
abstract: OBJECTIVE
  We wanted to clarify the relationship between the visibility of air cysts on CT images, the CT slice thickness and the size of the air cysts, with contact radiographs as the gold standard, for the accurate evaluation of honeycomb cysts.
  
  
  METHODS
  An inflated and fixed autopsied lung having idiopathic interstitial pneumonia was evaluated. The corresponding air cysts were identified on the contact radiographs of a 0.5 mm-thick-section specimen and also on the CT images of three different kinds of section thickness: 0.5, 1.0 and 2.5 mm. The maximal diameters of the air cysts were measured under a stereomicroscope.
  
  
  RESULTS
  A total of 341 air cysts were identified on the contact radiograph, and they were then evaluated. Sixty-six percent of air cysts 1 to 2 mm in diameter were detected by 0.5 mm slice thickness CT, while only 34% and 8% were detected by 1.0 and 2.5 mm slice thickness CT, respectively. Only 28% and 22% of air cysts less than 1 mm in diameter were detected by 0.5 and 1.0 mm slice thickness CT, respectively. CT with a 2.5 mm slice thickness could not demonstrate air cysts less than 1 mm in diameter.
  
  
  CONCLUSIONS
  The CT detection rate of honeycombing is significantly influenced both by the slice thickness and the size of the air cysts.
authors.affiliation: Department of Radiology, Nara Medical University, Otsu Shiga, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Nishimoto
authors.forename: Masashi
authors.initials: M
authors.lastname: Takahashi
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Murata
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Kichikawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D003560:Cysts / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D016707:Tissue Fixation / Q000379:methods; D014057:Tomography, X-Ray Computed