自动管电压选择技术在双源CT大螺距心脑一体化血管成像中的应用价值

Application of automated tube potential selection technique in high-pitch dual-source CTA for cardiocerebrovascular disease

目的探讨第三代双源CT大螺距心脑一体化血管成像中使用自动管电压选择技术在优化图像质量及降低辐射剂量中的作用。方法选择2019年10月~2020年11月首都医学大学宣武医院神经内科住院行冠状动脉及头颈动脉一体化CT扫描的老年患者100例,随机分为自动管电压组50例,固定管电压组50例。比较2组的一般临床资料、辐射剂量,并对图像质量进行主观及客观评价。结果自动管电压组实际管电流明显高于固定管电压组(P<0.01)。自动管电压组剂量长度乘积及有效剂量较固定管电压组明显减低[(121.84±37.17)mGy·cm vs(175.93±18.26)mGy·cm,P<0.01;(1.29±0.85)mSv vs(1.89±0.58)mSv,P<0.01]。2组冠状动脉主观评分比较,无统计学差异(P>0.05)。自动管电压组头颈动脉主观评分明显高于固定管电压组[(3.45±0.66)分vs(3.05±0.72)分,P<0.05]。2组各部位图像噪声、信噪比及对比噪声比比较,差异无统计学意义(P>0.05)。自动管电压组左冠状动脉主干、右冠状动脉主干、颈总动脉、颈内动脉、大脑中动脉及椎动脉CT值明显高于固定管电压组,差异有统计学意义(P<0.01)。结论第三代双源CT大螺距心脑一体化血管成像中使用自动管电压技术可明显降低辐射剂量,并能提供良好的图像质量,值得临床推广应用。

Objective To study the role of automated tube potential selection technique in optimizing the image quality and reducing the radiation dose of 3rd generation high-pitch dual-source CTA for cardiocerebrovascular diseases.Methods One hundred elderly patients who underwent high-pitch dual-source CTA for cardiocerebrovascular diseases were randomly divided into automatic tube potential selection group(n=50)and fixed tube potential group(n=50).Their general clinical data and radiation dose were compared and their image quality was subjectively and objectively evaluated.Results The tube current was significantly higher while the dose length product and effective radiation dose were significantly lower in automatic tube potential selection group than in fixed tube potential group(121.84±37.17 mGy·cm vs 175.93±18.26 mGy·cm,P<0.01;1.29±0.85 mSv vs 1.89±0.58 mSv,P<0.01).No significant difference was detected in subjective score of coronary artery between the two groups(P>0.05).The subjective score of cervical and carotid artery was significantly higher in automatic tube potential selection group than in fixed tube potential group(3.45±0.66 vs 3.05±0.72,P<0.05).No significant difference was detected in image noise,signal/noise ratio and contrast/noise ratio between the two groups(P>0.05).The CTA value of left main coronary artery,right main coronary artery,common carotid artery,internal carotid artery,middle cerebral artery and vertebral artery was significantly higher in automatic tube potential selection group than in fixed tube potential group(P<0.01).Conclusion The application of automated tube potential selection technique in 3rd generation high-pitch dual-source CTA for cardiocerebrovascular diseases can significantly reduce the radiation dose,achieve good image quality and is thus worthy of popularization in clinical practice.