低管电压结合低剂量对比剂在64层螺旋CT头颈部血管成像中的应用  

Feasibility of Low Tube Voltage Combined with Low Contrast Dose in 64-slice Spiral CT Cerebral and Carotid Arteriography

作　　者：王婕妤[1] 乔伟[2] 黎秋菊[1] 孙红彬[1] 孙鹤[1] 邹杰[1] 

机构地区：[1]中国医科大学附属第四医院放射科,辽宁沈阳110032 [2]中国医科大学附属盛京医院超声科,辽宁沈阳110004

出　　处：《中国医学影像学杂志》2015年第7期481-485,共5页Chinese Journal of Medical Imaging

摘　　要：目的探讨64层螺旋CT头颈部血管成像(CTA)低管电压结合低剂量对比剂扫描的可行性,对比低管电压低剂量与常规电压常规剂量对比剂扫描对头颈部血管的显示效果,并评估其对辐射剂量的影响。资料与方法前瞻性选取接受头颈部CTA检查的80例患者,随机分为对照组和低剂量组,每组各40例。对照组管电压120 k V,对比剂用量80 ml;低剂量组管电压80 k V,对比剂用量50 ml。比较两组动脉图像质量及静脉干扰评分、动脉强化CT值、信噪比(SNR)、对比噪声比(CNR)、辐射剂量。结果 2名医师对动脉图像质量评分、静脉干扰评分的一致性较高(Kappa=0.782、0.867,P<0.05)。两组动脉图像质量评分、静脉干扰评分、SNR、CNR比较,差异无统计学意义(Z=-0.864^-0.032,t=0.331~1.793,P>0.05)。低剂量组各动脉强化CT值均高于对照组(t=-8.789~1.715,P<0.05)。低剂量组容积CT剂量指数、剂量长度乘积和有效剂量均明显低于对照组(Z=-8.888,t=78.092、78.350,P<0.05)。结论在头颈部CTA检查中采用低管电压结合低剂量对比剂扫描,可以获得较好的图像质量,能够满足临床诊断需要,同时明显降低辐射剂量。Purpose To evaluate the feasibility of a low-dose contrast medium protocol for 64-slice spiral CT angiography（CTA） of cerebral and carotid using a low-tube-voltage setting, and to compare the display effect of cerebral and carotid arteries by low-tubevoltage low-dose contrast medium and routine-tube-voltage routine-dose contrast medium scanning, and to assess the effect on radiation dose. Materials and Methods Eighty consecutive patients were prospectively selected to perform cerebral and carotid CTA inspection. The patients were randomly divided into control group and low dose group with 40 people in each group. The voltage in control group was 120 k V and the contrast agent was 80 ml; those in low dose group were 80 k V and 50 ml, respectively. The artery image quality was evaluated and venous interference was scored. The CT value, signalto-noise ratio（SNR）, contrast-to-noise ratio（CNR） and radiation dose in both groups were statistically analyzed. Results The consistency of uniform in artery image quality score and venous interference score was rather high according to the assessment of two physicians（Kappa=0.782 and 0.867）. There was no statistical difference in artery image quality score, venous interference score, SNR and CNR between the two groups（Z=-0.864-- 0.032, P〉0.05）. The CT value in low dose group was higher than that in control group（differences with statistical significance, t=- 8.789-1.715, P〈0.05）. The CT dose index of volume, dose-length product and effective dose in low dose group were all significantly lower than those in control group（Z=- 8.888, t=78.092 and 78.350, respectively, P〈0.05）. Conclusion The use of low tube voltage and low contrast dose in cerebral and carotid CTA examination can result in high quality images which meets the diagnostic needs and obviously reduce radiation dosage.

关 键 词：体层摄影术 螺旋计算机 血管造影术 颈总动脉 颈内动脉 造影剂 剂量效应关系 药物 辐射剂量 

分 类 号：R445.3[医药卫生—影像医学与核医学]