title: Comparison of the effects of model-based iterative reconstruction and filtered back projection algorithms on software measurements in pulmonary subsolid nodules.
abstract: OBJECTIVE
  To evaluate the differences between filtered back projection (FBP) and model-based iterative reconstruction (MBIR) algorithms on semi-automatic measurements in subsolid nodules (SSNs).
  
  
  METHODS
  Unenhanced CT scans of 73 SSNs obtained using the same protocol and reconstructed with both FBP and MBIR algorithms were evaluated by two radiologists. Diameter, mean attenuation, mass and volume of whole nodules and their solid components were measured. Intra- and interobserver variability and differences between FBP and MBIR were then evaluated using Bland-Altman method and Wilcoxon tests.
  
  
  RESULTS
  Longest diameter, volume and mass of nodules and those of their solid components were significantly higher using MBIR (p < 0.05) with mean differences of 1.1% (limits of agreement, -6.4 to 8.5%), 3.2% (-20.9 to 27.3%) and 2.9% (-16.9 to 22.7%) and 3.2% (-20.5 to 27%), 6.3% (-51.9 to 64.6%), 6.6% (-50.1 to 63.3%), respectively. The limits of agreement between FBP and MBIR were within the range of intra- and interobserver variability for both algorithms with respect to the diameter, volume and mass of nodules and their solid components. There were no significant differences in intra- or interobserver variability between FBP and MBIR (p > 0.05).
  
  
  CONCLUSIONS
  Semi-automatic measurements of SSNs significantly differed between FBP and MBIR; however, the differences were within the range of measurement variability.
  
  
  CONCLUSIONS
  • Intra- and interobserver reproducibility of measurements did not differ between FBP and MBIR. • Differences in SSNs' semi-automatic measurement induced by reconstruction algorithms were not clinically significant. • Semi-automatic measurement may be conducted regardless of reconstruction algorithm. • SSNs' semi-automated classification agreement (pure vs. part-solid) did not significantly differ between algorithms.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.|Institute of Radiation Medicine, Seoul National University Medical Research Center, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Korea.|Clinique Universitaire de Radiologie et Imagerie Médicale (CURIM), Université Grenoble Alpes, Centre Hospitalier Universitaire de Grenoble, CS 10217, 38043, Grenoble Cedex 9, France.
authors.forename: Julien G
authors.initials: JG
authors.lastname: Cohen
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.|Institute of Radiation Medicine, Seoul National University Medical Research Center, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Korea.
authors.forename: Hyungjin
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.|Institute of Radiation Medicine, Seoul National University Medical Research Center, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Korea.
authors.forename: Su Bin
authors.initials: SB
authors.lastname: Park
authors.affiliation: Department of Radiology and Nuclear Medicine, Radboud University Nijmegen Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.
authors.forename: Bram
authors.initials: B
authors.lastname: van Ginneken
authors.affiliation: Clinique Universitaire de Radiologie et Imagerie Médicale (CURIM), Université Grenoble Alpes, Centre Hospitalier Universitaire de Grenoble, CS 10217, 38043, Grenoble Cedex 9, France.|INSERM U 823, Institut A Bonniot, 38700, La Tronche, France.
authors.forename: Gilbert R
authors.initials: GR
authors.lastname: Ferretti
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Chang Hyun
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea.|Institute of Radiation Medicine, Seoul National University Medical Research Center, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Korea.|Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jin Mo
authors.initials: JM
authors.lastname: Goo
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, South Korea. cmpark.morphius@gmail.com.|Institute of Radiation Medicine, Seoul National University Medical Research Center, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Korea. cmpark.morphius@gmail.com.|Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea. cmpark.morphius@gmail.com.
authors.forename: Chang Min
authors.initials: CM
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D055613:Multiple Pulmonary Nodules / Q000000981:diagnostic imaging* / Q000473:pathology; D015588:Observer Variation; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011877:Radionuclide Imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Iterative reconstruction; Lung neoplasms; Measurement variability; Multidetector computed tomography; Subsolid nodule