Multi-detector row CT angiography of the brain at various kilovoltage settings
Multi-detector row CT angiography of the brain at various kilovoltage settings
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DOI：
10.1148/radiol.2312030543
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发表时间：
2004-05-01
期刊：
影响因子：
19.7
通讯作者：
Reiser, MF
中科院分区：
文献类型：
--
作者：
Ertl-Wagner, BB;Hoffmann, RT;Reiser, MF
目的：探讨不同千伏条件下多层螺旋CT血管成像的图像质量和血管显示情况。材料和方法：对30例患者进行标准化CT扫描，连续3组，每组10例，分别在80、120和140千伏电压下进行检查。三名失明读者独立评估图像，并对图像质量参数、诊断置信度和颅内动脉和静脉的血管描绘进行分级。定量评估血管CT衰减值、CT剂量指数和剂量长度乘积。对于数据分析，使用Kruskal-Wallis非参数等级F检验来确定需要注意建模的趋势和变量。然后用广义估计方程对比例优势多项回归模型进行拟合，以说明数据的相关性。结果：千伏设置越高，图像质量越高(P<；.001)。在较低的千伏电压设置下，成像伪影的严重程度较高(P<；.001)，而主观评定的血管对比度在80千伏组低于120千伏组和140千伏组(P<；0.05)。120千伏组和140千伏组的诊断置信度较高(P<；.005)。大多数动脉和静脉结构的千伏电压设置较高时，血管轮廓较高。接近骨骼的结构和亚段动脉的差异更显著，而主要动脉分支和大静脉窦的差异不显著，部分差异不显著。千伏设定值越低，衰减值越高(P<；0.05)。平均剂量长度乘积可从594mGy.在140千伏组中增加到152mGy.结论：多层螺旋CT血管成像在不同的千伏电压设置下对图像质量和血管显示进行了多人研究，结果表明，高电压对邻近骨动脉和亚段动脉的血管的影响最明显。(C)RSNA，2004年。
PURPOSE: To investigate image quality and vascular delineation of multi-detector row computed tomographic (CT) angiography at various kilovoltage Settings.MATERIALS AND METHODS: Thirty patients were investigated with a standardized CT protocol, with three groups of 10 consecutive patients examined at 80, 120, and 140 kV, respectively. Three blinded readers independently evaluated images and graded image quality parameters, diagnostic confidence, and vascular delineation of intracranial arteries and veins. Vascular CT attenuation values, CT dose indices, and dose length products were assessed quantitatively. For data analysis, a Kruskal-Wallis nonparametric rank F test was used to identify trends and variables that required modeling attention. A proportional odds multinomial regression model was then fit with generalized estimating equations to account for the correlated nature of the data.RESULTS: Image quality was rated higher with higher kilovoltage settings (P < .001). The severity of imaging artifacts was higher with lower kilovoltage settings g g (P < .001), while the subjectively rated vessel contrast was lower in the 80-kV group than in the 120-kV group and the 140-kV group (P < .05). Diagnostic confidence was higher in the 120-kV group and 140-kV group (P < .005). Vascular delineation was higher with higher kilovoltage settings for most arterial and venous structures. Differences were more significant for structures in close topographic proximity to bone and for subsegmental arteries and were less significant and, in parts, not significant for the main arterial branches and the large venous sinus. Attenuation values were higher with lower kilovoltage settings (P < .05). The mean dose length product could be reduced from 594 mGy . cm in the 140-kV group to 152 mGy (.) cm in the 80-kV group.CONCLUSION: This multireader study of image quality and vessel delineation with cranial multi-detector row CT angiography at various kilovoltage settings demonstrated a superiority of higher voltages with most pronounced effects for vessels adjacent to bone and subsegmental arteries. (C) RSNA, 2004.