title: MDCT interpretation of the ascending aorta with semiautomated measurement software: improved reproducibility compared with manual techniques.
abstract: BACKGROUND
  Treatment decisions for ascending aortic aneurysms are guided by measurements from CT angiograms.
  
  
  OBJECTIVE
  The aim was to evaluate the reproducibility of these measurements by using manual techniques and advanced imaging software.
  
  
  METHODS
  Two radiologists measured maximal ascending aorta diameter on CT angiograms in 30 subjects at 4 separate reading sessions-2 with manual techniques and 2 with semiautomated software analysis. Interobserver and intraobserver variabilities were assessed with Bland-Altman plots and Spearman correlation coefficients.
  
  
  RESULTS
  Interobserver variability was smaller for the software-assisted method. Limits of agreement for the manual method were -4.2 mm and 9.2 mm compared with -4.0 mm and 4.6 mm for the software-assisted method; coefficients of repeatability were 6.8 mm and 4.3 mm. Intraobserver variability was inconsistent between readers. Strong correlation was found between observers who used both methods (R(2) = 0.8078-0.9881; P < .05 for all).
  
  
  CONCLUSIONS
  The use of an advanced imaging software for measurement of ascending aortic aneurysm reduces interobserver variability.
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, 601 N. Caroline Street, JHOC 3142, Box 0818, Baltimore, MD 21287, USA.
authors.forename: Sameer
authors.initials: S
authors.lastname: Ahmed
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, 601 N. Caroline Street, JHOC 3142, Box 0818, Baltimore, MD 21287, USA. Electronic address: szimme11@jhmi.edu.
authors.forename: Stefan L
authors.initials: SL
authors.lastname: Zimmerman
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, 601 N. Caroline Street, JHOC 3142, Box 0818, Baltimore, MD 21287, USA.
authors.forename: Pamela T
authors.initials: PT
authors.lastname: Johnson
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, 601 N. Caroline Street, JHOC 3142, Box 0818, Baltimore, MD 21287, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Lai
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, 601 N. Caroline Street, JHOC 3142, Box 0818, Baltimore, MD 21287, USA.
authors.forename: Satomi
authors.initials: S
authors.lastname: Kawamoto
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, 601 N. Caroline Street, JHOC 3142, Box 0818, Baltimore, MD 21287, USA.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Horton
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, 601 N. Caroline Street, JHOC 3142, Box 0818, Baltimore, MD 21287, USA.
authors.forename: Elliot K
authors.initials: EK
authors.lastname: Fishman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging*; D001027:Aortography / Q000379:methods*; D001331:Automation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D015588:Observer Variation; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012984:Software
keywords: Aneurysm; Aorta; CT angiogram; Centerline analysis; Measurement techniques; Measurement variability