Applied Imaging Science Laboratory, Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Circ Cardiovasc Imaging. 2010 Mar;3(2):179-86. doi: 10.1161/CIRCIMAGING.109.854307. Epub 2009 Dec 31.
To define and evaluate coronary contrast opacification gradients using prospectively ECG-gated single heart beat 320-detector row coronary angiography (CTA).
Thirty-six patients with normal coronary arteries determined by 320 x 0.5-mm detector row coronary CTA were retrospectively evaluated with customized image postprocessing software to measure Hounsfield Units at 1-mm intervals orthogonal to the artery center line. Linear regression determined correlation between mean Hounsfield Units and distance from the coronary ostium (regression slope defined as the distance gradient G(d)), lumen cross-sectional area (G(a)), and lumen short-axis diameter (G(s)). For each gradient, differences between the 3 coronary arteries were analyzed with ANOVA. Linear regression determined correlations between measured gradients, heart rate, body mass index, and cardiac phase. To determine feasibility in lesions, all 3 gradients were evaluated in 22 consecutive patients with left anterior descending artery lesions > or =50% stenosis. For all 3 coronary arteries in all patients, the gradients G(a) and G(s) were significantly different from zero (P<0.0001), highly linear (Pearson r values, 0.77 to 0.84), and had no significant difference between the left anterior descending, left circumflex, and right coronary arteries (P>0.503). The distance gradient G(d) demonstrated nonlinearities in a small number of vessels and was significantly smaller in the right coronary artery when compared with the left coronary system (P<0.001). Gradient variations between cardiac phases, heart rates, body mass index, and readers were low. Gradients in patients with lesions were significantly different (P<0.021) than in patients considered normal by CTA.
Measurement of contrast opacification gradients from temporally uniform coronary CTA demonstrates feasibility and reproducibility in patients with normal coronary arteries. For all patients, the gradients defined with respect to the coronary lumen cross-sectional area and short-axis diameters are highly linear, not significantly influenced by the coronary artery (left anterior descending artery versus left circumflex versus right coronary artery), and have only small variation with respect to patient parameters. Preliminary evaluation of gradients across coronary artery lesions is promising but requires additional study.
使用前瞻性 ECG 门控单心跳 320 探测器排冠状动脉造影（CTA）定义和评估冠状动脉对比显影梯度。
36 例经 320 x 0.5mm 探测器排冠状动脉 CTA 检查确定为正常冠状动脉的患者，使用定制的图像后处理软件进行回顾性评估，以测量与动脉中心线垂直的 1mm 间隔的 Hounsfield 单位。线性回归确定了平均 Hounsfield 单位与距冠状动脉口的距离（回归线斜率定义为距离梯度 G(d)）、管腔横截面积（G(a)）和管腔短轴直径（G(s)）之间的相关性。对于每个梯度，使用方差分析分析 3 条冠状动脉之间的差异。线性回归确定了测量梯度与心率、体重指数和心脏相位之间的相关性。为了确定在病变中的可行性，对 22 例左前降支病变>或=50%狭窄的连续患者的所有 3 个梯度进行了评估。对于所有患者的所有 3 条冠状动脉，梯度 G(a)和 G(s)均与零显著不同（P<0.0001），高度线性（Pearson r 值为 0.77 至 0.84），左前降支、左回旋支和右冠状动脉之间无显著差异（P>0.503）。右冠状动脉的距离梯度 G(d)在少数血管中呈现非线性，与左冠状动脉系统相比明显较小（P<0.001）。心脏相位、心率、体重指数和读者之间的梯度变化较小。病变患者的梯度明显不同于 CTA 确定的正常患者（P<0.021）。
从时间均匀的冠状动脉 CTA 测量对比显影梯度在正常冠状动脉患者中具有可行性和可重复性。对于所有患者，相对于冠状动脉管腔横截面积和短轴直径定义的梯度高度线性，不受冠状动脉（左前降支与左回旋支与右冠状动脉）影响，并且仅与患者参数有较小变化。梯度跨越冠状动脉病变的初步评估有希望，但需要进一步研究。
