Effect of Contrast Injection Protocols with Dose Adjusted to the Estimated Lean Patient Body Weight on Aortic Enhancement at CT Angiography
Effect of Contrast Injection Protocols with Dose Adjusted to the Estimated Lean Patient Body Weight on Aortic Enhancement at CT Angiography
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DOI：
10.2214/ajr.08.1407
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发表时间：
2009-04-01
影响因子：
5
通讯作者：
Yamashita, Yasuyuki
中科院分区：
文献类型：
--
作者：
Yanaga, Yumi;Awai, Kazuo;Yamashita, Yasuyuki
目标。本研究的目的是根据CT血管成像(CTA)患者估计的瘦体重(LBW)调整碘剂量对主动脉强化的影响。应用多层螺旋CT对97例(平均年龄67.4岁)确诊或可疑的主动脉病变患者进行了全主动脉CTA检查。将患者分为两组：总体重(TBW)组(n=49)和估计LBW组(n=48)。根据患者体重(TBW)和身高估算体重。TBW组和估算LBW组分别接受360 mg I/kg的TBW和450 mg I/kg的估算LBW造影剂。估计的低体重组与体重组的相对剂量比是基于这样一个事实，即平均体重为60公斤的日本成年人的标准体脂百分比是20%(360=0.8x450)。结果：估计低体重组和体重组的平均主动脉增强程度分别为308.9 HU和314.1 HU，两者之间无显著差异(Welch‘s t检验，p=0.61)。LBW组的四分位数范围小于TBW组(分别为52.8HU和79.1 HU)；估计LBW组的患者间变异性较低。TBW组和估计LBW组的主动脉衰减梯度分别为20.7HU和25.8HU，差异无统计学意义。结论：与使用基于TBW的剂量的CTA方案相比，使用估算的LBW量身定制剂量的CTA方案产生了更一致的主动脉增强，且患者间的变异性较小。
OBJECTIVE. The objective of our study was to investigate the effect on aortic enhancement of iodine doses adjusted for the patient estimated lean body weight (LBW) at CT angiography (CTA).SUBJECTS AND METHODS. CTA for the whole aorta using a 64-MDCT scanner was performed in 97 patients (mean age, 67.4 years) with confirmed or suspected aortoiliac disease. The patients were divided into two groups: a total body weight (TBW) group (n = 49) and an estimated LBW group (n = 48). LBW was estimated from the patient weight (TBW) and height. The TBW and estimated LBW groups received 360 mg I/kg of TBW and 450 mg I/kg of estimated LBW of contrast medium, respectively. The relative dose ratio for the estimated LBW group versus the TBW group was based on the fact that the standard percentage of body fat in Japanese adults with an average TBW of 60 kg is 20% (360 = 0.8 x 450). Differences in the degree of aortic enhancement and interpatient variability in aortic enhancement between the estimated LBW and TBW group were evaluated.RESULTS. Mean aortic enhancement was 308.9 HU for the estimated LBW group and 314.1 HU for the TBW group, indicating no significant difference in the degree of enhancement (Welch's t test, p = 0.61). The interquartile range was smaller for the LBW group than the TBW group (52.8 vs 79.1 HU, respectively); interpatient variability was lower in the estimated LBW group. The aortic attenuation gradient in the TBW group and estimated LBW group was 20.7 and 25.8 HU, respectively; the difference was not statistically significant.CONCLUSION. The CTA protocol using an estimated LBW-tailored dose yielded more consistent aortic enhancement with reduced interpatient variability than the CTA protocol using a TBW-based dose.