LDCT平扫联合ASiR算法在新型冠状病毒肺炎检查中的应用价值

Application value of LDCT combined with ASiR algorithm for diagnosing COVID-19

目的:为降低新型冠状病毒肺炎(以下简称“新冠肺炎”)患者进行胸部CT筛查与复查时所受的辐射剂量,探讨低剂量CT(low-dose computed tomography,LDCT)联合自适应统计迭代重建(adaptive statistical iterative reconstruction,ASiR)算法在新冠肺炎检查中的可行性。方法:回顾性分析经核酸检测确诊的26例(88次检查)新冠肺炎患者的临床资料,根据扫描方式分为原厂程序组和LDCT程序组。原厂程序组使用GE原厂的普通程序扫描,管电压为120 kV,自动管电流控制(250~450 mA);LDCT程序组使用LDCT联合ASiR算法扫描,管电压为100 kV,自动管电流控制(150~250 mA)。对比2组的图像质量、有效剂量(effective dose,ED)及质量剂量比(SNR/ED),并绘制ROC曲线。采用SPSS 17.0软件进行数据分析。结果:2组图像质量比较差异无统计学意义(P>0.05);LDCT程序组的ED低于原厂程序组,且质量剂量比高于原厂程序组,差异有统计学意义(P<0.01);ROC曲线显示质量剂量比的AUC最高(0.85)。结论:LDCT联合ASiR算法扫描能够在保证图像质量的前提下大幅降低患者所受的辐射剂量,在新冠肺炎筛查和复查中具有重要的应用价值。

Objective To explore the feasibility of diagnosing COVID-19 by combined low-dose computed tomography(LDCT)and adaptive statistical iterative reconstruction(ASiR)so as to decrease the exposure dose during chest CT screening and reexamination of COVID-19 patients.Methods A review of the clinical data of 26 COVID-19 patients(88 examinations)confirmed by nucleic acid testing was executed,which were categorized according to the mode of scanning into an original program group and LDCT program group.The original program group used GE's normal program scanning with 120 kV tube voltage and automatic tube current control(250-450 mA);the LDCT program group underwent scanning with LDCT combined with ASiR algorithm with a tube voltage of 100 kV and automatic tube current control(150-250 mA).The two groups were compared over image quality,effective dose(ED)and image quality/radiation dose(SNR/ED),and the ROC curve was drawn.SPSS 17.0 software was used for data analysis.Results There were no significant differences between the two groups in image quality(P>0.05);the LDCT program group had its ED lower while image quality/radiation dose higher significantly than those of the original program group(P<0.01);the ROC curve showed that the AUC of image quality/radiation dose gained the highest value(0.85).Conclusion LDCT combined with ASiR algorithm decreased greatly the exposure dose of the patient with the image quality ensured,and thus is of great significance for the screening and reexamination of COVID-19 patients.