title: Planimetric measurement of the regurgitant orifice area using multidetector CT for aortic regurgitation: a comparison with the use of echocardiography.
abstract: OBJECTIVE
  This study compared the area of the regurgitant orifice, as measured by the use of multidetector-row CT (MDCT), with the severity of aortic regurgitation (AR) as determined by the use of echocardiography for AR.
  
  
  METHODS
  In this study, 45 AR patients underwent electrocardiography-gated 40-slice or 64-slice MDCT and transthoracic or transesophageal echocardiography. We reconstructed CT data sets during mid-systolic to enddiastolic phases in 10% steps (20% and 35-95% of the R-R interval), planimetrically measuring the abnormally opened aortic valve area during diastole on CT reformatted images and comparing the area of the aortic regurgitant orifice (ARO) so measured with the severity of AR, as determined by echocardiography.
  
  
  RESULTS
  In the 14 patients found to have mild AR, the ARO area was 0.18+/-0.13 cm(2) (range, 0.04-0.54 cm(2)). In the 15 moderate AR patients, the ARO area was 0.36 +/- 0.23 cm(2) (range, 0.09-0.81 cm(2)). In the 16 severe AR patients, the ARO area was 1.00 +/- 0.51 cm(2) (range, 0.23-1.84 cm(2)). Receiver-operator characteristic curve analysis determined a sensitivity of 85% and a specificity of 82%, for a cutoff of 0.47 cm(2), to distinguish severe AR from less than severe AR with the use of CT (area under the curve = 0.91; 95% confidence interval, 0.84-1.00; p < 0.001).
  
  
  CONCLUSIONS
  Planimetric measurement of the ARO area using MDCT is useful for the quantitative evaluation of the severity of aortic regurgitation.
authors.affiliation: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.
authors.forename: Min Hee
authors.initials: MH
authors.lastname: Jeon
authors.forename: Yeon Hyeon
authors.initials: YH
authors.lastname: Choe
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Cho
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Pyo Won
authors.initials: PW
authors.lastname: Park
authors.forename: Jae K
authors.initials: JK
authors.lastname: Oh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000503:physiopathology; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging*; D019540:Area Under Curve; D001837:Body Weights and Measures / Q000379:methods; D004452:Echocardiography / Q000379:methods; D018618:Echocardiography, Doppler, Color / Q000379:methods; D017548:Echocardiography, Transesophageal / Q000379:methods; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult