title: Variability of ascending aorta diameter measurements as assessed with electrocardiography-gated multidetector computerized tomography and computer assisted diagnosis software.
abstract: Recently, morphometric measurements of the ascending aorta have been done with ECG-gated multidector computerized tomography (MDCT) to help the development of future novel transcatheter therapies (TCT); nevertheless, the variability of such measurements remains unknown. Thirty patients referred for ECG-gated CT thoracic angiography were evaluated. Continuous reformations of the ascending aorta, perpendicular to the centerline, were obtained automatically with a commercially available computer aided diagnosis (CAD). Then measurements of the maximal diameter were done with the CAD and manually by two observers (separately). Measurements were repeated one month later. The Bland-Altman method, Spearman coefficients, and a Wilcoxon signed-rank test were used to evaluate the variability, the correlation, and the differences between observers. The interobserver variability for maximal diameter between the two observers was up to 1.2 mm with limits of agreement [-1.5, +0.9] mm; whereas the intraobserver limits were [-1.2, +1.0] mm for the first observer and [-0.8, +0.8] mm for the second observer. The intraobserver CAD variability was 0.8 mm. The correlation was good between observers and the CAD (0.980-0.986); however, significant differences do exist (P<0.001). The maximum variability observed was 1.2 mm and should be considered in reports of measurements of the ascending aorta. The CAD is as reproducible as an experienced reader.
authors.affiliation: Department of Radiology and Cardiovascular and Metabolic Diseases Center, CHUV - University of Lausanne, Rue du Bugnon 46, CH-1011 Lausanne, Switzerland.
authors.forename: Tri-Linh Christian
authors.initials: TL
authors.lastname: Lu
authors.forename: Elena
authors.initials: E
authors.lastname: Rizzo
authors.forename: Pedro Manuel
authors.initials: PM
authors.lastname: Marques-Vidal
authors.forename: Ludwig Karl von
authors.initials: LK
authors.lastname: Segesser
authors.forename: Jamshid
authors.initials: J
authors.lastname: Dehmeshki
authors.forename: Salah Dine
authors.initials: SD
authors.lastname: Qanadli
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000473:pathology*; D001027:Aortography / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed