“双低”技术主动脉MSCTA临床应用研究  

Application of double-low technique to aortic MSCTA

作　　者：余红胜[1] 沈又利[1] 刘义康[2] 

机构地区：[1]孝感市康复医院放射科,湖北孝感432000 [2]华中科技大学同济医学院附属孝感医院放射科,湖北孝感432000

出　　处：《医疗卫生装备》2017年第2期76-79,88,共5页Chinese Medical Equipment Journal

摘　　要：目的:探讨"双低"技术应用于主动脉CT血管造影(CT angiography,CTA)的可行性。方法:搜集70例体质量指数(body mass index,BMI)≤25 kg/m^2且临床拟行主动脉CTA病例,前瞻性随机分为常规组和实验组,每组35例,均以4 ml/s速率注入碘海醇(350 mg I/ml)。常规组:120 k V、120 m As,对比剂用量1.5 ml/kg;实验组:90 k V、120 m As,对比剂用量1.0 ml/kg,其他扫描参数一致。记录并计算所有病例的辐射剂量、对比剂用量和碘含量,对图像质量进行双盲法主观评价和客观评价。结果:(1)实验组容积CT剂量指数(CT dose index volumes,CTDIvol)、剂量长度乘积(dose length product,DLP)、有效剂量(effect dose,ED)显著低于常规组(P<0.05)。(2)图像主观评分一致性较好(Kappa值>0.6),图像质量评分均≥2分,满足诊断要求,组间差异无统计学意义(P>0.05)。(3)客观评价实验组主动脉各部血管CT值、图像噪声显著高于常规组(P<0.05);2组间信噪比(signal noise ratio,SNR)、对比噪声比(contrast to noise ratio,CNR)差异无统计学意义(P>0.05)。实验组对比剂碘含量均明显低于常规组(P<0.05)。结论:在BMI≤25 kg/m^2的患者中行"双低"技术主动脉CTA,不仅有效降低了受检者辐射剂量和对比剂碘量,而且获得图像质量完全满足诊断要求,具有较好的临床应用价值。Objective To discuss the feasibility of double-low technique applied in aortic MSCTA. Methods Totally 70 patients with BMI not more than 25 kg/m2 were divided into a routine group and an experimental group randomly and equally, and then went through aortic MSCTA. Iohexol（350 mg I/ml） was injected with the velocity of 4 ml/s. The routine group had the parameters as120 kV, 120 m As and 1.5 ml/kg contrast agent, and the experimental group had the parameters as 90 kV, 120 m As and 1.0 ml/kg contrast agent, while the other scanning parameters were kept the same in the two groups. The radiation doses, contrast agent doses and iodine contents were recorded in the two groups, and the image quality was assessed with double-blind method objectively and subjectively. Results The experimental group had the CT dose index volumes（CTDIvol）, dose length product（DLP） and effect dose（ED） significantly lower than those in the routine group（P〈0.05）. The two groups had the consistency of subjective scores（Kappa〉0.6） and image quality scores（not lower than 2） meet the desired requirements, and there were no significant differences between the scores（P〉0.05）. Objective evaluation showed that the signal values of aortic trunk and major branch vessels as well as image noise SD of the experimental group were obviously higher than those in the routine group（P〈0.05）. There were no statistical differences between the signal noise ratios（SNR） and contrast to noises（CNR） in the two groups（P〈0.05）, The iodine content in the contrast agent of the experimental group was significantly lower than that in the routine group（P〈0.05）. Conclusion Double-low technique applied in aortic MSCTA of the patient with BMI not more than 25 kg/m2 reduces the radiation dose and iodine content in the contrast agent, has the image quality meet the desired requirements, and thus is of great value for clinical application.

关 键 词：管电压 对比剂 团注追踪 主动脉 辐射剂量 多层螺旋CT 

分 类 号：R816.2[医药卫生—放射医学]