title: Spiral CT artifact that simulates aortic dissection: image reconstruction with use of 180 degrees and 360 degrees linear-interpolation algorithms.
abstract: OBJECTIVE
  To evaluate a computed tomographic (CT) artifact that simulates aortic dissection.
  
  
  METHODS
  Two groups of 65 patients underwent spiral CT of the chest for reasons other than suspected aortic dissection. In each group, two series of images (10-mm sections) were reconstructed with use of a 180 degrees or 360 degrees linear-interpolation algorithm. Series of images were read by two radiologists, and variance between interpretations was statistically measured.
  
  
  RESULTS
  Among series of images, artifacts were seen on 21-26 (32%-40%) with use of a 180 degrees algorithm and 41 (63%) and 44 (68%) with use of a 360 degrees algorithm. Concordance between reviewers was fair (kappa = 0.58, 0.59) or good (kappa = 0.65) with use of a 180 degrees algorithm and excellent (kappa = 0.92) with use of a 360 degrees algorithm. In one group, with use of a 180 degrees algorithm, two series of reconstructed images were separated by 5 mm; artifact was observed on seven (11%) CT studies (on both series of images) and was located along the left or left anterior side of the aorta.
  
  
  CONCLUSIONS
  To reduce the frequency of a spiral CT artifact that simulates aortic dissection, two series of segmented images can be reconstructed with a change of image position along the z axis of the aorta and use of a 180 degrees linear-interpolation algorithm.
authors.affiliation: Department of Radiology, Lyon-Sud Hospital, Pierre Benite, France.
authors.forename: P
authors.initials: P
authors.lastname: Loubeyre
authors.forename: E
authors.initials: E
authors.lastname: Angelie
authors.forename: F
authors.initials: F
authors.lastname: Grozel
authors.forename: H
authors.initials: H
authors.lastname: Abidi
authors.forename: V A
authors.initials: VA
authors.lastname: Minh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000784:Aortic Dissection / Q000000981:diagnostic imaging*; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging*; D016477:Artifacts; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods