Division of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
Catheter Cardiovasc Interv. 2011 Aug 1;78(2):214-22. doi: 10.1002/ccd.23047. Epub 2011 Jul 15.
Three-dimensional (3D) quantitative coronary angiography (QCA) requires two angiographic views to restore vessel dimensions. This study investigated the impact of acquisition angle differences (AADs) of the two angiographic views on the assessed dimensions by 3D QCA.
X-ray angiograms of an assembled brass phantom with different types of straight lesions were recorded at multiple angiographic projections. The projections were randomly matched as pairs and 3D QCA was performed in those pairs with AAD larger than 25°. The lesion length and diameter stenosis in three different lesions, a circular concentric severe lesion (A), a circular concentric moderate lesion (B), and a circular eccentric moderate lesion (C), were measured by 3D QCA. The acquisition protocol was repeated for a silicone bifurcation phantom, and the bifurcation angles and bifurcation core volume were measured by 3D QCA. The measurements were compared with the true dimensions if applicable and their correlation with AAD was studied.
50 matched pairs of angiographic views were analyzed for the brass phantom. The average value of AAD was 48.0 ± 14.1°. The percent diameter stenosis was slightly overestimated by 3D QCA for all lesions: A (error 1.2 ± 0.9%, P < 0.001); B (error 0.6 ± 0.5%, P < 0.001); C (error 1.1 ± 0.6%, P < 0.001). The correlation of the measurements with AAD was only significant for lesion A (R(2) = 0.151, P = 0.005). The lesion length was slightly overestimated by 3D QCA for lesion A (error 0.06 ± 0.18 mm, P = 0.026), but well assessed for lesion B (error -0.00 ± 0.16 mm, P = 0.950) and lesion C (error -0.01 ± 0.18 mm, P = 0.585). The correlation of the measurements with AAD was not significant for any lesion. Forty matched pairs of angiographic views were analyzed for the bifurcation phantom. The average value of AAD was 49.1 ± 15.4°. 3D QCA slightly overestimated the proximal angle (error 0.4 ± 1.1°, P = 0.046) and the distal angle (error 1.5 ± 1.3°, P < 0.001). The correlation with AAD was only significant for the distal angle (R(2) = 0.256, P = 0.001). The correlation of bifurcation core volume measurements with AAD was not significant (P = 0.750). Of the two aforementioned measurements with significant correlation with AAD, the errors tended to increase as AAD became larger.
3D QCA can be used to reliably assess vessel dimensions and bifurcation angles. Increasing the AAD of the two angiographic views does not increase accuracy and precision of 3D QCA for circular lesions or bifurcation dimensions.
三维（3D）定量冠状动脉造影（QCA）需要两个血管造影视图来恢复血管尺寸。本研究调查了两个血管造影视图的采集角度差异（AAD）对 3D QCA 评估尺寸的影响。
在多个血管造影投影中记录具有不同类型直病灶的组装黄铜模型的 X 射线血管造影。将投影随机匹配为对，并在 AAD 大于 25°的对中进行 3D QCA。通过 3D QCA 测量三个不同病变的病变长度和直径狭窄程度：圆形同心严重病变（A）、圆形同心中度病变（B）和圆形偏心中度病变（C）。如果适用，通过 3D QCA 比较获得的协议来测量分叉模型的分叉角度和分叉核心体积。并研究了它们与 AAD 的相关性。
对黄铜模型分析了 50 对匹配的血管造影视图。AAD 的平均数值为 48.0 ± 14.1°。所有病变的 3D QCA 对直径狭窄的估计都略有偏高：A（误差 1.2 ± 0.9%，P < 0.001）；B（误差 0.6 ± 0.5%，P < 0.001）；C（误差 1.1 ± 0.6%，P < 0.001）。只有病变 A 的测量值与 AAD 呈显著相关（R²=0.151，P=0.005）。病变 A 的 3D QCA 对病变长度的估计略有偏高（误差 0.06 ± 0.18mm，P=0.026），但对病变 B（误差 -0.00 ± 0.16mm，P=0.950）和病变 C（误差 -0.01 ± 0.18mm，P=0.585）的评估良好。任何病变的测量值与 AAD 之间均无显著相关性。对分叉模型分析了 40 对匹配的血管造影视图。AAD 的平均数值为 49.1 ± 15.4°。3D QCA 略高估了近侧角度（误差 0.4 ± 1.1°，P=0.046）和远侧角度（误差 1.5 ± 1.3°，P<0.001）。与 AAD 仅存在显著相关性（R²=0.256，P=0.001）。分叉核心体积测量值与 AAD 的相关性不显著（P=0.750）。在与 AAD 具有显著相关性的两个上述测量中，误差随着 AAD 的增加而增加。
3D QCA 可用于可靠地评估血管尺寸和分叉角度。增加两个血管造影视图的 AAD 不会增加圆形病变或分叉尺寸的 3D QCA 的准确性和精密度。
