J Am Coll Radiol 2010;7:754-773
Damini Dey, PhD Tiziano Schepis, MD Mohamed Marwan, MSc Piotr J.SIomka, PhD Daniel S. Berman, MD Stephan Achenbach, MD
Purpose: To determine the accuracy of a previously developed automated algorithm (AUTOPLAQ [APQ]) for rapid volu¬metric quantification of noncalcified and calcified plaque from coronary computed tomographic (CT) angiography in comparison with intravascular ultrasonography (US).
Materials and methods: This study was approved by the institutional review board and was HIPAA compliant; all patients provided written informed consent. APQ combines derived scan-specific atten-uation threshold levels for lumen, plaque, and knowledge-based segmentation of coronary arteries for quantification of plaque components. APQ was validated with retrospec¬tive analysis of 22 coronary atherosclerotic plaques in 20 patients imaged with coronary CT angiography and intravascular US within 2 days of each other. Coronary CT angiographic data were acquired by using dual-source CT. For each patient, well-defined plaques without calcifi¬cations were selected, and plaque volume was measured with APQ and manual tracing at CT and with intravascular US. Measurements were compared with paired t test, correlation, and Bland-Altman analysis.
Results: There was excellent correlation between noncalcified plaque volumes quantified with APQ and intravascular US (r - 0.94, P < .001), with no significant differences (P = .08). Mean plaque volume with intravascular US was 105.9 mm3 ± 83.5 (standard deviation) and with APQ was 116.6 mm3 ± 80.1. Mean plaque volume with manual tracing from CT was 100.8 mm3 ± 81.7 and with APQ was 116.6 mm3 ± 80.1, with excellent correlation (r = 0.92, P < .001) and no significant differences (P = .23).
Conclusion: Automated scan-specific threshold level-based quantifica-tion of plaque components from coronary CT angiog-raphy allows rapid, accurate measurement of noncalcified plaque volumes, compared with intravascular US, and re¬quires a fraction of the time needed for manual analysis.
