Klein J L, Boccuzzi S J, Treasure C B, Manoukian S V, Vogel R A, Beauman G J, Fischman D, Savage M P, Weintaub W S
Emory University, Atlanta, Georgia, USA.
Am J Cardiol. 1996 Apr 15;77(10):815-22. doi: 10.1016/s0002-9149(97)89174-6.
Quantitative coronary angiography (QCA) has become an important tool for evaluating coronary angiograms. Many methodologic factors, such as the choice of frame to analyze, the selection of the "normal," segment and the method of edge detection used may affect the results of QCA. The sequential steps in performing QCA, including a comparison of visual and automated edge-detection methodologies, were evaluated using 12 precision-drilled phantoms and 20 patient films. Normal diameter, minimal lumen diameter, and diameter stenosis were measured. In the phantom studies, the measurements from both visual and automated systems correlated well with the true measurements of the phantoms and between systems (all r values >0.92). To study the difference between methodologies on QCA results as influenced by the choice of frame and normal segment analyzed, the patient films were analyzed independently in 3 separate rounds of interpretation. In round 1, each system's operator individually chose frames and normal segments for analysis. In round 2, both systems analyzed the same preselected frames, but independently chose normal segments. In round 3, both systems analyzed the same preselected normal segments and frames. The intersystem correlations between visual and automatic systems for rounds 1, 2, and 3 were: normal diameter, r = 0.25, r = 0.37, and r = 0.75, respectively; minimal lumen diameter, r = 0.79, r = 0.86, and r = 0.85, respectively; and diameter stenosis, r = 0.65, r = 0.73, and r = 0.87, respectively. The manual edge-detection and automated edge-detection systems used in this study are reasonably accurate and consistent on phantom studies. In patient studies, the nonautomated processes (choice of frame and normal segment for analysis) produced significant differences in the QCA results, thus illustrating that operator-dependent factors other than edge detection are very important in QCA.
定量冠状动脉造影（QCA）已成为评估冠状动脉造影的重要工具。许多方法学因素，如分析帧的选择、“正常”节段的选取以及所采用的边缘检测方法等，都可能影响QCA的结果。使用12个精密钻孔模型和20份患者影像对进行QCA的连续步骤，包括视觉和自动边缘检测方法的比较，进行了评估。测量了正常直径、最小管腔直径和直径狭窄程度。在模型研究中，视觉和自动系统的测量结果与模型的真实测量值以及系统之间的测量结果相关性良好（所有r值>0.92）。为了研究受分析帧和正常节段选择影响的方法学对QCA结果的差异，对患者影像在3轮独立解读中进行了分析。在第1轮中，每个系统的操作员分别选择帧和正常节段进行分析。在第2轮中，两个系统分析相同的预选帧，但独立选择正常节段。在第3轮中，两个系统分析相同的预选正常节段和帧。第1、2和3轮视觉和自动系统之间的系统间相关性分别为：正常直径，r = 0.25、r = 0.37和r = 0.75；最小管腔直径，r = 0.79、r = 0.86和r = 0.85；直径狭窄，r = 0.65、r = 0.73和r = 0.87。本研究中使用的手动边缘检测和自动边缘检测系统在模型研究中相当准确且一致。在患者研究中，非自动化过程（分析帧和正常节段的选择）在QCA结果中产生了显著差异，从而说明除边缘检测外，依赖操作员的因素在QCA中非常重要。
