Objective: To evaluate optimal methodology for quantitative plaque volume analysis by coronary CT angiography (QCT). Methods: Fifty-one coronary artery segments were evaluated and contour measurements based on two different methods [(1) no gap, or (2) fixed 0.3-mm gap between inner and outer boundary] were compared with intravascular ultrasound (IVUS). In addition, three different window width (WW) and level (WL) settings [fixed (740/220) Hounsfield unit (HU), adjusted (155 % and 65 % of mean luminal intensity of the segment, and aorta adjusted (155 % and 65 % of mean luminal intensity of central aorta)] were used for semiautomated plaque volume analysis. Results: For boundary detection, the no gap method led to underestimation compared with IVUS (105.4 ± 82.3 vs. 136.1 ± 72.8 mm3, p < 0.001), while fixed 0.3-mm gap showed no difference between IVUS and QCT (136.1 ± 72.8 vs. 139.8 ± 93.9 mm3, p = 0.50). Comparison of the three different window settings demonstrated that the aorta adjusted setting underestimated (120.5 ± 74.3 vs. 136.1 ± 72.8 mm3, p = 0.003), while fixed setting showed the least mean difference compared with IVUS (3.8 ± 39.8 mm3, p = 0.50). Conclusion: For plaque volumetric assessment, optimal results were obtained with fixed 0.3-mm gap with fixed HU setting (740/220). Key Points: • Quantitative plaque volume analysis by coronary CT angiography has recently emerged. • Different boundary detection methods and window width and level settings were evaluated. • Fixed 0.3-mm gap with fixed HU setting (740/220) afforded optimal results.
Bibliographical noteFunding Information:
The scientific guarantor of this publication is Hyuk-Jae Chang, MD, PhD. All authors disclose no conflict of interest. This study has received funding from the Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (MSIP) (No. 2012027176). No complex statistical methods were necessary for this paper. Institutional review board approval was obtained. Written informed consent was waived by the institutional review board.
© 2015, European Society of Radiology.
All Science Journal Classification (ASJC) codes
- Radiology Nuclear Medicine and imaging