MR扩散加权成像及ADC值评价小鼠H22肝癌模型的初步研究

目的：探讨MR扩散加权成像（DWI）结合频谱预饱和反转恢复（SPIR）技术在小鼠H22肝癌模型成像的技术参数及其可行性。方法：于小鼠右前肢腋窝下皮下注射0.2ml H22腹水细胞,制造小鼠H22肝癌模型,第15天进行MR检查,测量肿瘤组织的表观扩散系数（ADC）,测量T2WI及DWI图像中肿瘤实质部分的信号强度及信噪比,利用三维最大强度投影（3D-MIP）重组及黑白反转技术,观测病变显示效果。结果：在扩散敏感因子（b）=600s/mm^2的DWI图像中,肝癌多表现为高信号,其内的坏死部分为低信号,肿瘤实质部分的ADC值为：1421±160s/mm^2,经MIP重组及黑白反转技术,病变周围组织信号被抑制,有利于肿瘤的显示,但部分荷瘤小鼠DWI图像存在伪影。结论：MR DWI及ADC值测量在评价小鼠H22肝癌模型显示病灶方面有一定优势。

Initial study on H22 hepatocarcinoma transplanted model in mice by MR diffusion weighted imaging and ADC value

Objective：To explore the feasibility of echo planer with spectral presaturation inversion recovery（SPIR） diffusion weighted imaging（DWI） in H22 hepatocarcinoma transplanted mice model for imaging parameters and the feasibility.Methods：Subcutaneous injection in the right forelimb armpit of the mice with 0.2 ml H22 ascites cells was performed to create mice H22 hepatoma model,MR study had been done after 15 days to survey the apparent diffusion coefficient（ADC） of the tumor,and the SNR of T2WI,DWI.The effect of lesions was observed using three-dimensional maximum intensity projection（3D-MIP） and black-and-white reversal recombinant technology was observed.Results：In the DWI images with the diffusion sensitized factor（b）=600 s/mm2,hepatoma tissue displayed high signal,and the signal of necrosis was lower,the ADC value of the parenchymatous tissue was 1421±160 s/mm2.By restructuring and black-and-white reversal MIP technology,the signal of the surrounding tissue around the lesions was suppressed,but there were some artifacts in the DWI.Conclusion：MR DWI and ADC value have a certain advantage with conclusion in the evaluation of the H22 hepatocarcinoma transplanted model in mice Ⅰ.