低剂量CT扫描参数对肺磨玻璃结节容积测量的影响  

The effect of low-dose CT scanning parameters on volume measurement of pulmonary ground glass nodules

作　　者：于安宏 马延贺[1] 高洪岩 张洪[1] YU Anhong;MA Yanhe;GAO Hongyan;ZHANG Hong(Department of Radiology,Tianjin Chest Hospital,Tianjin 300222,China)

机构地区：[1]天津市胸科医院影像科,天津300222

出　　处：《实用放射学杂志》2021年第5期842-845,共4页Journal of Practical Radiology

基　　金：天津市科技计划项目(18ZXZNSY00400).

摘　　要：目的探讨低剂量CT扫描参数对仿真胸部体模中磨玻璃结节(GGN)容积测量准确度的影响.方法将15个模拟GGN(直径为5mm、10mm、15mm,CT值为-600HU)随机置于仿真胸部体模中,使用PhilipsBrillianceiCT以不同扫描方案对仿真体模行CT扫描,管电压分别采用120kV、100kV、80kV;管电流分别采用50mAs、30mAs、15mAs;组合成9种不同的扫描方案.应用肺结节分析软件对体模内的结节进行标记和识别,自动计算出各扫描方案下的结节容积测量值.应用单因素方差分析评估不同扫描条件下不同直径的GGN之间相对容积误差(RVE)的差异.结果3种不同直径的结节RVE有统计学差异(P<0.05);管电压80kV组的结节RVE与其他管电压组均有显著差异(P<0.05);管电流15mAs组与其他2组(50mAs组、30mAs组)的结节RVE有显著差异(P<0.05);其他各组间无统计学差异(P>0.05).结论GGN的直径大小与扫描参数对容积测量准确度有影响,对直径较小的结节,可适当提高扫描条件.Objective To investigate the impact of low-dose CT scanning protocols on the volume measurement accuracy of ground glass nodules(GGN)in an anthropomorphic chest phantom.Methods Fifteen simulated GGN(diameter of 5 mm,10 mm,15 mm,CT value of—600 HU)were randomly placed in the anthropomorphic chest phantom.Different scanning schemes was used to scan the phantom by using Philips Brilliance iCT with the tube voltage of 120 kV,100 kV,80 kV,and the tube current of 50 mAs,30 mAs,15 mAs,respectively.Nine different scanning schemes were derived then.The pulmonary nodule analysis software was used to label and identify the nodules in the phantom,and the nodule volume under each scanning scheme was calculated automatically.One Way ANOVA was used to evaluate the differences of the relative volume error(RVE)among GGN with different diameters under different scanning conditions.Results The RVE of nodules with the three different diameters were statistically different(P<0.05);the RVE of nodules in the tube voltage 80 kV group was significantly different from that in the other two groups(P<0.05);the RVE of nodules in the tube current of 15 mAs was significantly different from that in the other two groups(50 mAs and 30 mAs)(P<0.05);no significant differences were observed among the other groups(P>0.05).Conclusion The diameter of GGN and scanning parameters play a significant role in the accuracy of volume measurement.The scanning condition can be appropriately improved for GGN with a smaller diameter.

关 键 词：磨玻璃结节 低剂量 计算机体层成像 体模 

分 类 号：R563[医药卫生—呼吸系统] R814.42[医药卫生—内科学]