80kV管电压联合SAFIRE技术应用于大螺距胸主动脉CT成像的可行性研究  

The feasibility study on 80 kV low tube voltage combined with SAFIRE technique in high-pitch spiral scan of CT thoracic angiography

作　　者：陈丹[1] 周嘉慧[1] 周祖华 贾崇富[3] 

机构地区：[1]山东省威海市立医院CT室,山东威海264200 [2]海军旅顺红营子离职干部休养所卫生所,辽宁旅顺116041 [3]大连医科大学附属第一医院心脏检查室,辽宁大连116011

出　　处：《医学影像学杂志》2017年第7期1235-1238,共4页Journal of Medical Imaging

摘　　要：目的评估并比较80k V低管电压联合SAFIRE技术大螺距胸主动脉CT成像(CTTA)的辐射剂量及图像质量。方法对临床怀疑患有胸主动脉疾病、20kg/m2<BMI≤25kg/m2的60例患者实施前瞻性大螺距CTTA,A组(30例,管电压80k V),B组(30例,管电压100k V),两组螺距均为3.2,管电流采用CARE Dose 4D技术,并分别进行SAFIRE、FBP重建。比较相同管电压下SAFIRE算法与FBP重建的图像质量;并比较A组SAFIRE算法与B组FBP重建的胸主动脉图像CT值、噪声(SD)、信号-噪声比(SNR)、对比-噪声比(CNR)、以及有效辐射剂量。结果 A、B两组内SAFIRE技术较FBP重建的图像质量明显提高;A组SAFIRE的图像噪声高于B组FBP重建(42.4±9.6)HU、(29.8±6.8)HU,P<0.01),但两组的SNR分别为(15.5±3.1、15.8±3.2,P>0.05)、CNR分别为(14.5±2.9、14.3±2.8,P>0.05),差别无统计学意义。A、B两组的有效辐射剂量分别为(0.79±0.09)m Sv、(1.72±0.13)m Sv,A组较B组降低了约56%。结论与100k V管电压、FBP重建相比,应用80k V管电压联合SAFIRE技术进行CTTA扫描,能在保证图像质量前提下大大降低有效辐射剂量。Objective To assess the image quality and radiation dose of high-pitch spiral scan of CT thoracic angiography （CTTA） using 80 kV tube voltage and SAFIRE.Methods 60 consecutive patients with 20 kg/m2〈body mass index （BMI）≤25 kg/m2 who had suspected thoracic aortic disease underwent high-pitch CTTA, Two thoracic CTA protocols （group A： n=30, 80 kV;group B： n=30, 100 kV） were compared.The parameters of CT scans were 3.2 pitch, automatic tube current modulation （CARE dosed 4 D）, SAFIRE and FBP for medium soft convolution kernel.First, we compared the image quality between SAFIRE and FBP reconstruction in the same group, then, compared the image noise,signal-to-noise ratio （SNR） , contrast-to-noise ratio （CNR） and radiation dose in matched groups （group A with SAFIRE, group B with FBP）.Results In the each group, the image noise with SAFIRE was greatly better than with FBP.In matched groups, the image noise was significantly higher with SAFIRE in group A than with FBP in group B〔（42.4±9.6） HU, （29.8±6.8） HU, P〈0.01〕.But there were no significant differences in SNR（15.5±3.1, 15.8±3.2, P〉0.05）, CNR（14.5±2.9, 14.3±2.8, P〉0.05） beteen them.The effective radiation dose of group A and B was 〔（0.79±0.09） mSv, （1.72 ±0.13） mSv, P〈0.01）, reduced about 56% in group A than group B.Conclusion To compared with 100kV voltage and FBP, high-pitch spiral scan of CTTA using 80 kV and SAFIRE can greatly reduce the radiation dose, and the image quality has no obvious difference.

关 键 词：胸主动脉 大螺距 图像质量 辐射剂量 体层摄影术 X线计算机 

分 类 号：R543.1[医药卫生—心血管疾病] R814.42[医药卫生—内科学]