7.0T MR-DTI评估大鼠脑胶质瘤瘤周浸润组织各向异性分数及纤维密度指数与皮质脊髓束损伤分级的相关性研究  

The Relevance Study of 7.0T MR-DTI Parameters of Fractional Anisotropy and Fiber Density Index Evaluating Peritumoral Infiltrating Tissue in Glioma in Rats with Injury Grades of Corticospinal Tracts

作　　者：贾晓雄 张国斌[1,2] 夏鹤春 Jia Xiaoxiong;Zhang Guobin;Xia Hechun(Department of Neurosurgery,Tianjin Huanhu Hospital,Tianjin 300350,China;Brain Trauma&Neurosurgical Critical Care Center,Tianjin Huanhu Hospital,Tianjin 300350,China;Department of Neurosurgery,General Hospital of Ningxia Medical University,Yinchuan Ningxia 750001,China;Incubation Base of National Key Laboratory for Cerebrocranial Diseases,Ningxia Medical University,Yinchuan Ningxia 750001,China)

机构地区：[1]天津市环湖医院神经外科,天津300350 [2]天津市颅脑损伤抢救中心,天津300350 [3]宁夏医科大学总医院神经外科,宁夏银川750001 [4]宁夏颅脑疾病国家重点实验室,宁夏银川750001

出　　处：《医疗装备》2021年第22期1-4,共4页Medical Equipment

基　　金：国家自然科学基金项目(81260373);宁夏医科大学校级项目(XM2015082)。

摘　　要：目的探讨弥散张量成像(DTI)参数各向异性分数(FA)及纤维密度指数(FDi)与大鼠脑胶质瘤影响下的皮质脊髓束不同损伤程度的相关性。方法建立14只大鼠脑胶质瘤模型,应用7.0T小动物磁共振于建模后第10天行DTI和T2WI成像,测量瘤周及健侧相对应区域的FA和FDi,并计算相对各向异性分数(rFA,患侧FA/健侧FA)和相对纤维密度指数(rFDi,患侧FDi/健侧FDi);大鼠处死后,免疫组化染色观察瘤周区域肿瘤细胞浸润和肿瘤细胞增殖指数;对DTI参数、病理结果及皮质脊髓束损伤程度进行相关性分析。结果大鼠脑胶质瘤瘤周区域FA(0.6014)、FDi(1.5761)较健侧对称区域FA(0.6964)、FDi(5.5299)降低,且rFA、rFDi与瘤周区域恶性肿瘤细胞数(r=-0.8581,r=-0.5077)及增殖指数(r=-0.8411,r=-0.5755)呈负相关;DTI显示,不同程度皮质脊髓束受损,与轻度皮质脊髓束受损相比,重度纤维束受损区域rFA降低,差异有统计学意义(P<0.05),rFDi仅表现为下降趋势,而无统计学意义(P>0.05)。结论在涉及皮质脊髓束受损的大鼠脑胶质瘤中,DTI参数FA和FDi可以为不同程度受损皮质脊髓束提供有价值的信息;通过DTI量化的指标可以为描述皮质脊髓束与恶性肿瘤之间的关系提供帮助。Objective This research aimed to evaluate the injury grades of the corticospinal tract involving glioma in rats using fractional anisotropy(FA)and fiber density index(FDi)by diffusion tensor imaging(DTI).Methods 14 rats underwent 7.0T small animal MRI(DTI and T2WI)on day 10 after glioma cells implantation.The FA and FDi were acquired in peritumoral and contralateral areas,and the relative fractional anisotropy(rFA,ipsilateral FA/contralateral FA)and the relative fiber density index(rFDi,ipsilateral FDi/contralateral FDi)in the peritumoral areas were calculated.All rats were sacrificed after MRI scanning,the invasion of glioma cells and glioma cells proliferation index were observed by immuohistochemical staining.The correlations among DTI parameters,pathological results and the injury grades of the corticospinal tract were analyzed.Results Compared to FA(0.6964)and FDi(5.5299)values in contralateral areas,FA(0.6014)and FDi(1.5761)values significant decreased in the peritumoral areas.Negative correlations were observed among malignant tumor cells counts(r=-0.8581,r=-0.5077),proliferation index(r=-0.8411,r=-0.5755)and rFA and rFDi values in the peritumoral areas.The DTI showed that the corticospinal tract injured at different degrees and the rFA value of the severely injured corticospinal tract was lower than that of the mildly injured ones,with statistically significant(P<0.05),the FDi values in the corticospinal tract injury grade groups did not significantly differ but showed a decreasing trend.Conclusions FA and FDi may be used to assess the injury grades of corticospinal tracts involving glioma in rats.Our data suggest that these parameters may be used to provide useful information of delineating the relationship between glioma and the corticospinal tract.

关 键 词：脑胶质瘤 弥散张量成像 各向异性分数 纤维密度指数 皮质脊髓束 

分 类 号：R445.2[医药卫生—影像医学与核医学] R739.41[医药卫生—诊断学]