Department of Medical Imaging, Jinan Military General Hospital, China.
Acad Radiol. 2012 Mar;19(3):281-8. doi: 10.1016/j.acra.2011.11.004. Epub 2011 Dec 27.
The aim of this study was to prospectively assess the effect of low-tube voltage (80 kVp) 320-detector row volume computed tomographic (CT) angiography (L-VCTA) in the detection of intracranial aneurysms, with three-dimensional (3D) spin digital subtraction angiography (DSA) as the gold standard.
Forty-eight patients with clinically suspected subarachnoid hemorrhages were divided into two groups. One group underwent L-VCTA and DSA, while the other group underwent conventional-tube voltage (120 kVp) volume CT angiography (C-VCTA) and DSA. Vascular enhancement, image quality, detection accuracy of aneurysms, and radiation dose were compared between the two groups.
For objective image quality, the L-VCTA group had higher mean vessel attenuation, correlated with higher image noise and lower signal-to-noise ratio, than the C-VCTA group. For subjective image quality, there were no significant differences between the two groups regarding scores for arterial enhancement, depiction of small arterial detail, interference of venous structures, and overall image quality scores. The mean effective dose for the L-VCTA group was significantly lower than for the C-VCTA group (0.56 ± 0.25 vs 1.84 ± 0.002 mSv), with a reduction of radiation dose of 69.73%. With 3D DSA as the reference standard, the sensitivity, specificity, and accuracy in the L-VCTA and C-VCTA groups were 94.12%, 100%, 94.4% and 100%, 100%, and 100%, respectively. In both groups, there were significant correlations for maximum aneurysm diameter measurements between volume CT angiography and 3D DSA; no statistical difference in the mean maximum diameter of each aneurysm was measured between volume CT angiography and 3D DSA.
L-VCTA is helpful in detecting intracranial aneurysms, with results similar to those of 3D DSA, but at a lower radiation dose than C-VCTA.
本研究旨在前瞻性评估低管电压（80kVp）320 排容积 CT 血管造影（L-VCTA）在颅内动脉瘤检测中的作用，以三维（3D）旋转数字减影血管造影（DSA）为金标准。
将 48 例临床疑似蛛网膜下腔出血患者分为两组，一组行 L-VCTA 和 DSA 检查，另一组行常规管电压（120kVp）容积 CT 血管造影（C-VCTA）和 DSA 检查。比较两组患者血管增强程度、图像质量、动脉瘤检出准确率及辐射剂量。
客观图像质量方面，L-VCTA 组平均血管衰减值高于 C-VCTA 组，与图像噪声较高、信噪比较低相关。主观图像质量方面，两组患者动脉增强评分、小动脉细节显示评分、静脉结构干扰评分和整体图像质量评分差异均无统计学意义。L-VCTA 组的有效辐射剂量明显低于 C-VCTA 组（0.56±0.25比 1.84±0.002mSv），降低了 69.73%。以 3D DSA 为参考标准，L-VCTA 组和 C-VCTA 组的敏感度、特异度和准确率分别为 94.12%、100%、94.4%和 100%、100%、100%。两组容积 CT 血管造影与 3D DSA 测量最大动脉瘤直径均有显著相关性，容积 CT 血管造影与 3D DSA 测量的各动脉瘤平均最大直径无统计学差异。
L-VCTA 有助于颅内动脉瘤的检测，结果与 3D DSA 相似，但辐射剂量低于 C-VCTA。
