Chatzizisis Yiannis S, George Elizabeth, Cai Tianrun, Fulwadhva Urvi P, Kumamaru Kanako K, Schultz Kurt, Fujisawa Yasuko, Rassi Carlos, Steigner Michael, Mather Richard T, Blankstein Ron, Rybicki Frank J, Mitsouras Dimitrios
Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Int J Cardiovasc Imaging. 2014 Aug;30(6):1181-9. doi: 10.1007/s10554-014-0446-4. Epub 2014 May 18.
Coronary computed tomography angiography (CCTA) contrast opacification gradients, or transluminal attenuation gradients (TAG) offer incremental value to predict functionally significant lesions. This study introduces and evaluates an automated gradients software package that can potentially supplant current, labor-intensive manual TAG calculation methods. All 60 major coronary arteries in 20 patients who underwent a clinically indicated single heart beat 320 × 0.5 mm detector row CCTA were retrospectively evaluated by two readers using a previously validated manual measurement approach and two additional readers who used the new automated gradient software. Accuracy of the automated method against the manual measurements, considered the reference standard, was assessed via linear regression and Bland-Altman analyses. Inter- and intra-observer reproducibility and factors that can affect accuracy or reproducibility of both manual and automated TAG measurements, including CAD severity and iterative reconstruction, were also assessed. Analysis time was reduced by 68% when compared to manual TAG measurement. There was excellent correlation between automated TAG and the reference standard manual TAG. Bland-Altman analyses indicated low mean differences (1 HU/cm) and narrower inter- and intra-observer limits of agreement for automated compared to manual measurements (25 and 36% reduction with automated software, respectively). Among patient and technical factors assessed, none affected agreement of manual and automated TAG measurement. Automated 320 × 0.5 mm detector row gradient software reduces computation time by 68% with high accuracy and reproducibility.
冠状动脉计算机断层血管造影（CCTA）对比剂充盈梯度，即管腔衰减梯度（TAG），在预测功能上显著的病变方面具有额外价值。本研究介绍并评估了一种自动化梯度软件包，它有可能取代当前劳动强度大的手动TAG计算方法。对20例因临床需要接受单心跳320×0.5毫米探测器排CCTA检查的患者的所有60条主要冠状动脉进行了回顾性评估，两名阅片者使用先前验证过的手动测量方法，另外两名阅片者使用新的自动化梯度软件。通过线性回归和布兰德-奥特曼分析评估自动化方法相对于被视为参考标准的手动测量的准确性。还评估了观察者间和观察者内的可重复性以及可能影响手动和自动化TAG测量准确性或可重复性的因素，包括CAD严重程度和迭代重建。与手动TAG测量相比，分析时间减少了68%。自动化TAG与参考标准手动TAG之间具有极好的相关性。布兰德-奥特曼分析表明，与手动测量相比，自动化测量的平均差异较低（1 HU/cm），观察者间和观察者内的一致性界限更窄（分别减少25%和36%）。在评估的患者和技术因素中，没有一个影响手动和自动化TAG测量的一致性。自动化320×0.5毫米探测器排梯度软件将计算时间减少了68%，具有高精度和可重复性。
