MR体素内不相干运动扩散加权成像对直肠腺癌T分期及分化程度的应用价值研究

The value of MR intravoxel incoherent motion diffusion weighted imaging in T stage and differentiated degree of rectal adenocarcinoma

目的通探讨体素内不相干运动扩散加权成像(intravoxel incoherent motion diffusion weighted imaging,IVIM-DWI)各定量参数值对直肠腺癌分期、分化程度的应用价值。材料与方法采用GE3.0 T MR扫描仪获得48例经肠镜证实为直肠腺癌患者术前影像学资料,并收集患者术后病理资料(单纯腺癌42例,腺癌伴部分粘液腺癌6例)。利用GE AW4.5工作站对图像进行后处理,获得单纯直肠腺癌不同分期、分化程度的表观扩散系数(apparent diffusion coefficient,ADC)、单纯扩散系数(D)、灌注相关扩散系数(D*)和灌注分数(f)值。直肠腺癌不同分期、分化程度间各参数应用ANOVA,组间两两比较采用LSD法。结果 ADC及D在直肠腺癌不同T分期及分化程度之间差异均有统计学意义,T2-T4期直肠腺癌的ADC值分别为(1.200±0.117)×10^(-3))mm^2/s、(0.913±0.104)×10^(-3) mm^2/s、(0.786±0.450)×10^(-3) mm^2/s,D值分别为(0.737±0.055)×10^(-3) mm^2/s、(0.608±0.091)×10^(-3) mm^2/s、(0.593±0.041)×10^(-3) mm^2/s,高-低分化直肠腺癌的ADC值分别为(1.353±0.080)×10^(-3) mm^2/s、(0.984±0.028)×10^(-3) mm^2/s、(0.8 0 8±0.0 7 5)×1 0^(-3) mm^2/s,D值分别为(0.805±0.085)×1 0^(-3) mm^2/s、(0.645±0.081)×10^(-3) mm^2/s、(0.525±0.057)×10^(-3) mm^2/s,D*和f值在直肠腺癌不同T分期及分化程度之间差异无统计学意义。结论直肠腺癌病灶的ADC、D值可在一定程度上反映肿瘤分期、分化特点,IVIM-DWI作为常规MR的补充序列,为临床最佳治疗方案的选择提供更多信息支持。

Objective：To investigate the value of intravoxel incoherent motion diffusion weighted imaging（IVIM-DWI） quantitative parameters in T stage and differentiated degree of rectal adenocarcinoma.Materials and Methods：Fourtyeight cases of rectal adenocarcinoma confirmed by colonoscopy underwent 3.0 T MR examination,their clinicopathologic data were collected（42 cases were pure adenocarcinoma,6 cases were adenocarcinoma with partial mucinous adenocarcinoma）.GE AW4.5 workstation was used to calculate the value of ADC,D,D＊ and f of various T stages and differentiated degree.All parameters of various T stages and differentiated degree were compared by ANOVA and comparison between the two groups by LSD.Results：The ADC and D value in various T stage and in various degrees of differentiation were all statistically significant,for rectal adenocarcinoma of T2-T4,the value of ADC were（1.200±0.117）×10^-3 mm^2/s,（0.913±0.104）×10^-3 mm^2/s,（0.786±0.450）×10^-3 mm^2/s,The value of D were（0.737±0.055）×10^-3 mm^2/s,（0.608±0.091）×10^-3 mm^2/s,（0.593±0.041）×10^-3 mm^2/s,the value of ADC in high,medium and low differentiation were（1.353±0.080）×10^-3 mm^2/s,（0.984±0.028）×10^-3 mm^2/s,（0.808±0.075）×10^-3 mm^2/s respectively,the value of D in high,medium and low differentation were（0.805±0.085）×10^-3 mm^2/s,（0.645±0.081）×10^-3 mm^2/s,（0.525±0.057）×10^-3 mm^2/s,D＊ and f value were no significant difference.Conclusion：ADC and D value are able to reflect T stage and differentiation features of rectal adenocarcinoma,IVIM-DWI can serve as a complement sequence for conventional MR sequences,can provide more information to choose the best treatment.