低管电压迭代重建冠状动脉CT成像的图像质量和辐射剂量  

Image quality and radiation dose of coronary CT angiography in iterative reconstruction using low tube voltage

作　　者：赵承琳[1] 王照谦[1] 贾崇富[1] 杨志强[1] 孙喜霞[1] 卢晓娟[1] 刘兴众[1] 郑飞[1] 申敬顺[1] 

机构地区：[1]大连医科大学附属第一医院心脏CT科,116011

出　　处：《中华老年心脑血管病杂志》2014年第3期259-262,共4页Chinese Journal of Geriatric Heart,Brain and Vessel Diseases

摘　　要：目的评价低管电压迭代重建(IR)冠状动脉CT成像(CCTA)的质量和辐射剂量。方法选择接受低管电压CCTA检查患者50例,其中体质量指数<25kg/m2 25例(A组)和体质量指数≥25kg/m2 25例(C组),分别采用80kV和100kV管电压进行IR。另选与A组和C组性别、年龄和体质量指数相匹配的B组25例和D组25例患者接受标准管电压CCTA检查,分别采用100kV和120kV管电压,进行IR和滤波反投影(FBP)重建。分别比较A组IR与C组FBP重建以及B组IR与D组FBP重建的图像噪声、信号-噪声比率(SNR)、对比-噪声比率(CNR)、图像质量评分以及有效辐射剂量。结果与B组FBP重建比较,A组IR的CT值、图像噪声明显升高(P<0.05,P<0.01),有效辐射剂量明显降低(P<0.01),2组SNR、CNR及图像质量评分比较,差异无统计学意义(P>0.05)。与D组FBP重建比较,C组IR的CT值、图像噪声、SNR及CNR明显升高(P<0.05,P<0.01),有效辐射剂量明显降低(P<0.01),2组图像质量评分比较,差异无统计学意义(P>0.05)。结论与标准管电压FBP重建CCTA比较,低管电压IR CCTA不仅能提供质量相接近的CCTA,而且有效辐射剂量降低约50%。Objective To assess the image quality and radiation dose of coronary CT angiography （CCTA） in IR using low tube voltage.Methods Fifty patients who underwent CCTA using low tube voltage were divided into group A with their BMI〈25 kg/m2 and group C with their BMI≥ 25 kg/m2.Patients in group A received IR using 80 kV tube voltage and those in group C underwent IR using 100 kV tube voltage.Anther sex-,age-and BMI-matched 50 patients were divided into group B （n=25） and group D （n=25）.Patients in group B received IR and filtered back projection （FBP） reconstruction using 100 kV tube voltage and those in group D underwent IR and FBP reconstruction using 120 kV tube voltage.The image noise,SNR,CNR,image quality and radiation dose of IR in groups A and B were compared with those of FBP reconstruction in groups C and D.Results The CT image noise of IR was significantly higher while the radiation dose of IR was significantly lower in group A than that of RBP reconstruction in group B （P〈0.05,P〈 0.01）.The CT image noise,SNR and CNR of IR were significantly higher while the radiation dose of IR was significantly lower in group C than in group D （P〈0.05,P〈0.01）.Conclusion CCTA in IR using low tube voltage can provide the similar CCTA as in FBP reconstruction using standard tube voltage and reduce about 50% of the effective radiation dose.

关 键 词：体层摄影术 X线计算机 辐射剂量 图像处理 计算机辅助 冠状动脉疾病 

分 类 号：R816.2[医药卫生—放射医学]