Initial evaluation of coronary images from 320-detector row computed tomography
Initial evaluation of coronary images from 320-detector row computed tomography
复制标题
DOI：
10.1007/s10554-008-9308-2
复制
发表时间：
2008-06-01
影响因子：
2.1
通讯作者：
Di Carli, Marcelo F.
中科院分区：
文献类型：
--
作者：
Rybicki, Frank J.;Otero, Hansel J.;Di Carli, Marcelo F.
目的评价320排螺旋CT冠状动脉成像的图像质量和造影剂混浊程度。患者剂量估计前瞻性和回顾性心电门控;说明320层CT和冠状动脉导管插入术之间的初始相关性。方法回顾性评价40例患者的影像学表现，包括主观评价影像质量和对比剂显影（碘帕醇370 mg I/ml 80 ml，生理盐水40 ml）。使用口处和2.5 mm直径处的感兴趣区域混浊测量值来确定单次心跳中成像的冠状动脉中的造影剂混浊梯度（定义为近端减去远端HU测量值）。比较了前瞻性与回顾性ECG门控、两种体重指数分类（30 kg/m2截止值）以及单次与两次心跳采集的估计有效剂量。当可用时，CT结果与冠状动脉导管检查结果相关。结果89%以上的动脉节段（15节段模型）图像质量良好。图像退化的最常见原因是心脏运动。1例患者的一个节段被认为不可评价。几乎普遍认为造影剂显影效果极佳。平均Hounsfield单位（HU）大于350;冠状动脉造影剂浑浊梯度为30-50 HU。回顾性ECG门控、体型较大的患者和两次心跳成像的患者剂量更大。对于最常见（n = 25）方案（120 kV，400 mA，前瞻性ECG门控，60-100%相位窗口，16 cm头尾覆盖，单次心跳），平均剂量为6.8 +/- 1.4 mSv。所有的CT结果证实了在四个病人接受冠状动脉插管。结论320层螺旋CT冠状动脉成像质量稳定，碘造影剂显影不明显。这些患者接受了关于碘负荷、前瞻性ECG门控相位窗和头尾覆盖范围的保守方案扫描。未来的工作将集中在降低对比度和辐射剂量，同时保持图像质量。
Purpose To evaluate image quality and contrast opacification from coronary images acquired from 320-detector row computed tomography (CT). Patient dose is estimated for prospective and retrospective ECG-gating; initial correlation between 320-slice CT and coronary catheterization is illustrated. Methods Retrospective image evaluation from forty consecutive patients included subjective assessment of image quality and contrast opacification (80 ml iopamidol 370 mg I/ml followed by 40 ml saline). Region of interest opacification measurements at the ostium and at 2.5 mm diameter were used to determine the gradient of contrast opacification (defined as the proximal minus distal HU measurements) in coronary arteries imaged in a single heartbeat. Estimated effective dose was compared for prospective versus retrospective ECG-gating, two body mass index categories (30 kg/m(2) cutoff), and single versus two heartbeat acquisition. When available, CT findings were correlated with those from coronary catheterization. Results Over 89% of arterial segments (15 segment model) had excellent image quality. The most common reason for image degradation was cardiac motion. One segment in one patient was considered unevaluable. Contrast opacification was almost universally considered excellent. The mean Hounsfield units (HU) was greater than 350; the coronary contrast opacification gradient was 30-50 HU. Patient doses were greater for retrospective ECG-gating, larger patients, and those imaged with two heartbeats. For the most common (n = 25) protocol (120 kV, 400 mA, prospective ECG-gating, 60-100% phase window, 16 cm craniocaudal coverage, single heartbeat), the mean dose was 6.8 +/- 1.4 mSv. All CT findings were confirmed in the four patients who underwent coronary catheterization. Conclusion Initial 320-detector row coronary CT images have consistently excellent quality and iodinated contrast opacification. These patients were scanned with conservative protocols with respect to iodine load, prospective ECG-gating phase window, and craniocaudal coverage. Future work will focus on lowering contrast and radiation dose while maintaining image quality.