3.0T磁共振IVIM-DWI参数与直肠中分化腺癌T分期相关性的初步研究

目的：探讨3.0T MR 体素内不相干运动-扩散加权成像(IVIM-DWI)参数与直肠中分化腺癌 T 分期的关系。方法收集37例直肠中分化腺癌患者的直肠 MRI 图像(包括 IVIM-DWI 序列)及临床资料；根据肿瘤是否突破固有肌层,将 T 分期分为未突破组(T1、T2期)和突破组(T3、T4期)；测量直肠癌与正常直肠壁真实扩散系数(D)、假扩散系数(D?)、灌注分数(f)和表观扩散系数(ADC)值,比较直肠癌与正常直肠壁,不同 T 分期,不同分组直肠癌各参数值之间的差异,分析 IVIM-DWI 参数和 ADC 值与直肠中分化腺癌 T 分期的关系。结果直肠癌的 D、D?、f 和 ADC 值均低于正常直肠壁,其中 D、f 和 ADC 值差异有统计学意义(P <0.05)；不同 T 分期肿瘤 D 和 D?值的差异有统计学意义,LSD 法两两比较显示 T1期与 T4期,T3期与 T4期肿瘤的 D?值差异有统计学意义(P =0.017、0.003),T2期与 T3期肿瘤 D 值差异有统计学意义(P =0.005)；未突破组与突破组肿瘤 D 值分别约(0.93±0.16)×10-3 mm2/s、(0.77±0.19)×10-3 mm2/s,D?值分别约(12.6±2.44)×10-3 mm2/s、(12.3±3.49)×10-3 mm2/s,f值分别约(27.1±2.94)%、(24.6±4.13)%,ADC 值分别约(0.95±0.09)×10-3 mm2/s、(0.87±0.12)×10-3 mm2/s,其中 D 值的差异有统计学意义(t=2.512,P =0.017)。结论IVIM-DWI 参数和 ADC 值能够区分直肠癌和正常直肠壁,D 值可以辅助鉴别直肠癌是否突破固有肌层。

Correlation between parameters of intravoxel incoherent motion DWI at 3.0 Tesla and T staging of moderately differentiated adenocarcinoma of rectum:a preliminary study

Objective To investigate the relationships between the parameters of intravoxel incoherent motion (IVIM)DWI at 3.0 Tesla and T staging of moderately differentiated adenocarcinoma of rectum.Methods Clinical data and MRI findings including con-ventional imaging and IVIM-DWI were collected in a total of 37 patients with moderately differentiated adenocarcinoma of rectum proven by pathology.The patients were divided into two groups without (staging T1 and T2)or with myometrial invasion (T3 and T4).The D,D? ,f and ADC values of rectal cancer and normal rectal wall were measured and were compared between the lesion and normal rectal wall,between both groups and among different T stages.The relationships of the parameters of IVIM-DWI and ADC values with the T staging of moderately differentiated adenocarcinoma of rectum were analyzed.Results The D,D? ,f and ADC val-ues of rectal cancer were lower than those of normal rectal wall with statistical differences in D,f and ADC values (P <0.05).The differences in D and D? values among different T stages were statistically significant,and LSD Duncan test showed that the differ-ence in D? value between T1 and T4 (P =0.01 7)and between T3 and T4 (P =0.003)and in D value between T2 and T3 (P =0.005) were statistically significant.The D,f,D? and ADC values of noninvasion group and invasion one were (0.93±0.1 6)×10 -3 mm2/s versus (0.77±0.1 9)×10 -3 mm2/s,(27.1±2.94)% versus (24.6 ±4.13)%,(12.6±2.44)×10 -3 mm2/s versus (12.3±3.49)× 10 -3 mm2/s,and (0.95±0.09)×10 -3 mm2/s versus (0.87 ±0.12)×10 -3 mm2/s respectively,and the difference in D value was statistically significant (t=2.5 12,P =0.01 7).Conclusion The parameters of IVIM-DWI and the ADC values are different in rectal cancer and normal rectal wall,and the D value may help to identify the tumor invasion into the muscularis propria.