title: Variability of aortic valve calcification measurement with multislice spiral computed tomography.
abstract: OBJECTIVE
  We sought to assess the variability of aortic valve calcifications (AVCs) regarding the reconstruction window at different heart phases using multislice-spiral computed tomography.
  
  
  METHODS
  A total of 46 patients (26 men; mean age. 65 years) underwent AVC scoring with multislice-spiral computed tomography (12 x 0.75 mm, 120 kV, 133 mAseff). Image reconstruction was performed every 10% of the RR-interval (0-90%). AVC was quantified using Agatston score, calcium volume, and calcium mass. Images were assessed for least motion artifacts. Coefficients of variation and Wilcoxon test were calculated.
  
  
  RESULTS
  AVC scores are lowest at 60% and highest at 0% of the RR-interval (P < 0.001). Mean coefficients of variation were 36.2% (Agatston score), 38.7% (calcium volume), and 32.9% (calcium mass). At 60% (50-70%). minimal motion artifacts and the lowest variability of the scores were found.
  
  
  CONCLUSIONS
  AVC scores show large variability depending on the point of image reconstruction. Diastolic image reconstruction at 60% of the RR-interval is recommended.
authors.affiliation: Department of Diagnostic Radiology, RWTH Aachen University, Germany. ruhl@rad.rwth-aachen.de
authors.forename: Karl M
authors.initials: KM
authors.lastname: Ruhl
authors.forename: Marco
authors.initials: M
authors.lastname: Das
authors.forename: Ralf
authors.initials: R
authors.lastname: Koos
authors.forename: Georg
authors.initials: G
authors.lastname: Mühlenbruch
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Flohr
authors.forename: Joachim E
authors.initials: JE
authors.lastname: Wildberger
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Günther
authors.forename: Andreas H
authors.initials: AH
authors.lastname: Mahnken
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging*; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging*; D002114:Calcinosis / Q000000981:diagnostic imaging*; D003971:Diastole; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011829:Radiation Dosage; D012720:Severity of Illness Index; D036542:Tomography, Spiral Computed / Q000379:methods*