兔大腿VX2移植瘤模型磁共振扩散成像研究

采用大腿肌肉注射法建立兔VX2肿瘤模型,于造模后第7天、14天及21天进行磁共振成像(MRI)平扫、增强及扩散加权成像(DWI)检查,观察不同时期MRI表现。并于造模后第21天对照大体标本测量结果比较DWI及T2WI图像肿瘤最大径,同时比较肿瘤实体部分与髂窝内转移淋巴结的表观弥散系数(ADC)值。结果显示,造模后第7天,12只模型兔MRI常规及DWI图像均可见成瘤;第14天,2例肿瘤内出现坏死灶;第21天,12例肿瘤内均出现坏死,DWI图像可发现局部淋巴结转移灶,DWI及T2WI图像肿瘤最大径与大体标本测量结果差别无统计学意义。髂窝内转移淋巴结的ADC值与原发肿瘤实体部分ADC值间差别无统计学意义。DWI可以监测兔大腿VX2肿瘤生长,有效区分肿瘤早期坏死成分,并判断相应引流区域淋巴结的性质。

Magnetic Resonance Diffusion Weighted Imaging in Rabbit VX2 Thigh Implantation Tumor Model

Rabit VX2tumor model was made by injecting tumor tissue suspension into thigh muscles.7days,14 days and 21days after the injection,MR plain scan、contrast enhancement scan and diffusion-weighted imaging(DWI) were performed in these rabbits,respectively.Imaging findings of routine MR and DWI were observed.On the 21st day,the biggest length of the tumor in DWI and T2WI were measured,and compared with pathology measurement.And the differences of the ADC value between the solid part of the tumor and the metastatic lymph node were compared.The results showed that 7days after injection,DWI and T2WI demonstrated the tumor in all of the rabbits.14 days after injection,necrosis could be found in 2cases.21days after injection,necrosis could be found in all cases;DWI showed the metastatic lymph node in the ipsilateral fossa iliaca;there were no differences of the biggest tumor length in DWI and T2WI and pathology measurement;there were no differences of ADC value between the solid part of the tumor and the metastatic lymph node.DWI could monitor the growth of tumor,demonstrate the necrosis part and differentiate the quality of lymph node.