目的 探讨兔肝VX2瘤活体二维多体素^1H-MRS动态变化特征。材料与方法 对14只兔肝VX2瘤荷瘤兔分两期进行活体2D^1 H-MRS和常规MRI检查,观察肿瘤中心部分、肿瘤周围部分与瘤周正常肝组织的代谢物波峰变化,测量代谢物峰下积分面积比值。取MRS检查相应部位标本进行常规病理学检查,并进行PAS染色,测量积分光密度。结果 肿瘤中心部分的脂质(Lip)、胆碱化合物(Cho)和糖原和葡萄糖复合物(Gbu)波峰与瘤周正常肝组织差别较大。肿瘤周围部分除Lip峰高于瘤周正常肝组织以外,Cho和Glyu峰差异不大。肿瘤中心部分的Cho/Lip和Glyu/Lip值均较瘤周正常肝组织低(P〈0.05),肿瘤周围部分与瘤周正常肝组织无显著性差异(P〉0.05)。第二期三个部位的Glx/Lip、Cho/Lip、Glyu/Lip比值均较第一期明显降低(P〈0.05)。瘤周正常肝组织PAS染色积分光密度值与Glyu/Lip值之间存在显著线性相关关系(r=0.627,P〈0.05)。结论 活体2D^1 H-MRS能动态显示兔肝VX2瘤不同区域和不同时期主要代谢物的变化,在一定程度上反映了肝组织糖原储备及肿瘤的生长、增殖、坏死情况。
Objective To dynamically evaluate in vivo two-dimensional (2D) muhi-voxel hydrogen 1 magnetic resonance spectroscopic ( ^l H-MRS) findings in the rabbit VX2 tumor model. Material and Methods Both in vivo 2D H-MR spectroscopy and MR imaging were performed in 14 rabbit VX2 tumors for liver cancers at two stages. The peak areas of glutamine and glutamate complex (Glx), glycogen and glucose complex (Glyu), choline (Cho), and lipid (Lip) were measured on the liver spectra. The histopathologic features were correlated with the in vivo ^1 H-MR spectroscopic findings at each stage of liver cancers. Results There was significant difference between the peak areas of Lip, Cho, and Glyu in the center of the cancer and those in the adjacent liver with Cho/Lip and Glyu/Lip ratios in the center of the cancer lower than those in the adjacent liver (P 〈0.05 ). However, there was no significant difference be- tween the peak areas of metabolites in the peripheral part of the cancer and those in the adjacent liver except that the peak area of Lip in the peripheral part of the cancer was higher than that in the adjacent liver. Glx/Lip, Cho/Lip, and Glyu/Lip ratios in the cancer and adjacent liver at the second stage were lower than those at the first stage (P 〈0.05 ). There was a linear correlation between integrated optical density values on the Periodic Acid Schiff (PAS) staining and the Glyu/Lip ratio in adjacent liver of the liver cancer ( P 〈 0.05 ). Conclusion In vivo 2D ^l H-MRS could demonstrate changes of the peak areas of the metabolites in different parts of the VX2 tumor and adjacent liver at different sta- ges, which might reflect approximately behaviors of the VX2 tumor.