直肠癌表观弥散系数测量稳定性评估:高低b值不同信号激励次数的影响  

Impact of Different Number of Excitations on Measurement of ADC of Rectal Cancer

作　　者：李纪强 周慧赟 董海鹏 夏益涵 王康宁 吴梦雄 LI Jiqiang;ZHOU Huiyun;DONG Haipeng;XIA Yihan;WANG Kangning;WU Mengxiong

机构地区：[1]上海交通大学附属瑞金医院放射科,上海市200025

出　　处：《中国医学计算机成像杂志》2024年第6期698-702,共5页Chinese Computed Medical Imaging

基　　金：国家自然科学基金(82271934;82101986)。

摘　　要：目的:探讨扫描时间一致时,弥散加权成像(DWI)的高、低b值的信号激励次数(NEX)的设置不同对直肠癌表观弥散系数(ADC)测量稳定性的影响。方法:回顾性分析2023年3月至9月本院确诊的直肠癌患者38例。患者于术前行直肠MR扫描,其中DWI序列(b值分别为0和1000 s/mm^(2))在不改变扫描时间的前提下对b值采用了不同NEX设置,即DWI22(b=0和1000 s/mm^(2)时NEX均为2)和DWI13(b=0和1000 s/mm^(2)时NEX分别为1和3)。2名医生分别测量这2组图像病灶的ADC值,其中医生1在2周后重复测量1次。结果:基于DWI13的ADC值在2名医师间无统计学差异(P>0.05),医师1前后2次测量的ADC最小值(ADCmin,×10^(-3)mm^(2)/s)及ADC平均值(ADCave,×10^(-3)mm^(2)/s)无差异[ADCmin:589.105±249.307和597.316±213.854;ADCave:1054.658±325.478和953.45(876.68,1045.13);P>0.05]。基于DWI22测量的ADCmin值在医师1(第2次测量)与医师2间有统计学差异(P=0.039),且医师1前后2次测量的ADCave结果有统计学差异[993.450(894.525,1124.650)和955.242±172.805;P=0.004]。结论:扫描时间相同时,DWI13的ADC值更稳定。Purpose:To explore the impact of different number of excitations(NEX)for diffusion-weighted imaging(DWI)on the stability of apparent diffusion coefficient(ADC)of rectal cancer with the same scanning time.Methods:A total of 38 patients with pathologically confirmed rectal cancer were involved in this retrospective study in our hospital from March 2023 to September 2023.All patients underwent rectal MR scans within 2 weeks before surgery,and two different NEX settings(DWI13 and DWI22)were used for the DWI sequence(b-values of 0 and 1000 s/mm^(2))without altering the scan time.Two radiologists independently measured the ADC values of the tumor lesions in these two image sets,and radiologist 1 repeated the measurement after a two-week interval.Results:DWI13-derived ADCs were with no statistical difference between the two radiologists(all P>0.05),and the minimum ADC(ADCmin,×10^(-3)mm^(2)/s)and average ADC(ADCave,×10^(-3)mm^(2)/s)were similar between the former and later measurement of radiologist 1[ADCmin:589.105±249.307 and 597.316±213.854;ADCave:1054.658±325.478 and 953.45(876.68,1045.13);P>0.05].There was a statistical difference between DWI22-derived ADCmin measured by radiologist 1 for the second time and that by radiologist 2(P=0.039),and there were significant differences in the ADCave results between the two measurements by radiologist 1[993.450(894.525,1124.650)and 955.242±172.805;P=0.004].Conclusion:DWI13 provided significantly better stability in ADC measurement than DWI22 protocol with the same scanning time.

关 键 词：直肠肿瘤 激励次数 表观弥散系数 弥散加权成像 

分 类 号：R445.2[医药卫生—影像医学与核医学]