J Cardiovasc Comput Tomogr. 2015 Sep-Oct;9(5):446-53. doi: 10.1016/j.jcct.2015.06.001. Epub 2015 Jun 10.
Schuhbaeck A1, Otaki Y2, Achenbach S3, Schneider C4, Slomka P2, Berman DS2, Dey D5.
BACKGROUND: When coronary calcium scoring is performed in patients with suspected coronary artery disease, a separate noncontrast scan is acquired before contrast-enhanced coronary CT angiography (CTA). OBJECTIVE: Our aim was to develop and validate an automated method for calculating the coronary calcium score (CCS) from coronary CTA.
METHODS: We analyzed coronary CTA and noncontrast CT data sets of 84 patients (Agatston score >0). The CCS on noncontrast CT was measured using commercial methods. Coronary calcium volume was measured on coronary CTA using an automated standardized method with scan-specific calcium thresholds. Data sets were split into derivation (n = 40) and validation groups (n = 44). To calculate the CCS on coronary CTA, a conversion factor between calcium scores measured in noncontrast CT and the calcium volume measured on coronary CTA was derived by linear regression.
RESULTS: In the validation group, the median calculated CCS derived from CTA was 277 and 244 on noncontrast images (P = .12). This CCS showed an excellent correlation with the CCS from noncontrast images (Pearson, r = 0.95). In the validation group, 39 of 44 patients (88.6%) were classified into the same standard category (1-10, 11-100, 101-400, or >400) with an excellent agreement (weighted κ of 0.87). CONCLUSION: CCSs can be accurately measured from contrast-enhanced coronary CTA by using an automated, standardized method, obviating the need for a noncontrast scan.
Copyright © 2015 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.