自动管电压选择技术在不同体质量指数患者腹部增强 CT 扫描中的应用  

Application of automatic tube voltage selection for abdominal CT in various patient sizes

作　　者：张芮[1] 高剑波[1] 刘杰[1] 吕培杰[1] 胡丽丽[1] 侯平[1] 

机构地区：[1]郑州大学第一附属医院放射科,河南郑州450052

出　　处：《实用放射学杂志》2014年第6期1014-1017,1034,共5页Journal of Practical Radiology

摘　　要：目的：探讨自动管电压选择技术（ATVS）在不同体质量指数（BMI）患者腹部增强 CT 扫描中的应用价值。方法160例腹部增强 CT 扫描患者按扫描时间随机分为实验组80例（自动管电压选择技术）和对照组80例（常规120 kVp）,再根据 BMI 值分为4个亚组（A：BMI〈18.5 kg/m2；B：BMI 18.5-23.9 kg/m2；C：BMI 24-28.9 kg/m2；D：BMI ≥29 kg/m2）。对各组图像质量进行评分,并采用秩和检验进行比较；记录动脉期和静脉期图像的噪声及各部位对比噪声比（CNR）,并采用方差分析进行比较；观察对照组和实验组的辐射剂量,并采用 t 检验进行比较。结果实验组78.75%患者管电压自动调节为100 kVp,分布于 A-D 亚组,分别占60%（6/10）,80%（24/30）,90%（27/30）,60%（6/10）,平均 BMI（23.71±3.19）kg/m2。实验组 A-C 亚组有效剂量较对照组分别下降约35.09%、27.61%、19.08%（t=3.829、4.389、2.238,P =0.005、〈0.001、0.025）。实验组图像噪声较对照组稍增高,但总体图像质量可接受。结论自动管电压选择技术可降低 BMI〈28.9 kg/m2患者腹部增强 CT 扫描的辐射剂量。Objective The purpose of this study was to evaluate the effect of patient’s body mass index on applications of automatic tube voltage selection （ATVS）for contrast-enhanced abdominal CT.Methods 1 60 patients underwent contrast-enhanced ab-dominal CT scan were assigned into the study group （ATVS technique）and the control group （120 kVp）with equal size （both n =80）according to the scanning mode.The two groups were both divided into four subgroups according to BMI （A：BMI 〈18.5 kg/m2 ;B：BMI 18.5-23.9 kg/m2 ;C：BMI 24-28.9 kg/m2 ;D：BMI ≥29 kg/m2 ）.Image quality were assessed and compared with Rank-sum test.Analysis of variance was used to compare differences in mean contrast-to-noise ratio （CNR）and image noise a-mong the two groups.Two sample t tests were used to compare the radiation dose.Results In the study group,tube voltage of 100 kVp were selected highest（78.75%）and distributed from subgroups A to D,accounting for 60%,80%,90% and 60% respectively, with average BMI of （23.71±3.1 9）kg/m2 .Compared to control group,the effective dose of study group from subgroups A to C reduced by 35.09%,27.61% and 1 9.08% respectively（t=3.829,4.389,2.238,P =0.005,〈0.001,0.025）.Despite the higher image noise in study group,the overall image quality was acceptable.Conclusion The contrast-enhanced abdominal CT with AVTS technique can reduce radiation dose in patients with BMI smaller than 28.9 kg/m2 .

关 键 词：计算机体层成像 体质量指数 辐射剂量 图像质量 

分 类 号：R814.42[医药卫生—影像医学与核医学] R323.3[医药卫生—放射医学]