title: Reproducibility of computer-aided volumetry of artificial small pulmonary nodules in ex vivo porcine lungs.
abstract: OBJECTIVE
  The main purpose of this study was to investigate the reproducibility of computed tomography (CT)-based volumetric measurements of small pulmonary nodules.
  
  
  METHODS
  We implanted 70 artificial pulmonary nodules in 5 ex vivo porcine lungs in a dedicated chest phantom. The lungs were scanned 5 times consecutively with multislice-CT (collimation 16 x 0.75 mm, slice thickness 1 mm, reconstruction increment 0.7 mm). A commercial software package was used for lesion volumetry. The authors differentiated between intrascan reproducibility, interscan reproducibility, and results from semiautomatic and postprocessed volumetry.
  
  
  RESULTS
  Analysis of intrascan reproducibility revealed a mean variation coefficient of 6.2% for semiautomatic volumetry and of 0.7% for human adapted volumetry. For interscan reproducibility a mean variation coefficient of 9.2% and for human adapted volumetry a mean of 3.7% was detected.
  
  
  CONCLUSIONS
  The presented volumetry software showed a high reproducibility that can be expected to detect nodule growth with a high degree of certainty.
authors.affiliation: Department of Diagnostic Radiology, University Hospital Schleswig-Holstein Campus Kiel, Germany. Hendrikbolte@rad.uni-kiel.de
authors.forename: Hendrik
authors.initials: H
authors.lastname: Bolte
authors.forename: Christian
authors.initials: C
authors.lastname: Riedel
authors.forename: Thomas
authors.initials: T
authors.lastname: Jahnke
authors.forename: Nevin
authors.initials: N
authors.lastname: Inan
authors.forename: Sandra
authors.initials: S
authors.lastname: Freitag
authors.forename: Gerhard
authors.initials: G
authors.lastname: Kohl
authors.forename: Martin
authors.initials: M
authors.lastname: Heller
authors.forename: Jürgen
authors.initials: J
authors.lastname: Biederer
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D066298:In Vitro Techniques; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D019047:Phantoms, Imaging; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D012984:Software; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging*; D018709:Statistics, Nonparametric; D013552:Swine; D014057:Tomography, X-Ray Computed / Q000379:methods*