中文摘要：

目的：探索锰离子增强磁共振成像（MEMRI）在大鼠视觉中枢核团立体定位中的价值。方法 SD 大鼠36只,分成3组。A 组（1 6只）使用 MEMRI 定位法；B 组（1 6只）使用传统解剖图谱定位；C 组（4只）使用 A 组所取得的数据定位并穿刺中枢核团。A 组定位方法为提前在单侧眼球内注射氯化锰（MnCL2）水溶液（30 mmol/L×3μL）,24 h 后行 MRI 确定对侧上丘、外侧膝状体位置；B 组为根据图谱确定上述核团位置。随后,A、B 2组均经颅骨穿刺视觉核团后,注入3%荧光金溶液1μL,5 d 后处死大鼠并取出视网膜铺片,在荧光显微镜下观察视网膜神经节细胞（RGCs）标记情况。C 组则根据 A 组中取得的定位数据确定核团位置,穿刺并注射 MnCL2溶液（30 mmol/L×0.5μL）1 h 后,使用 MRI 观察强化区域,直接验证 MEMRI 定位数据的可靠性。结果 A 组RGCs 标记成功15只（93.8%）,B 组 RGCs 标记成功10只（62.5%）。A 组的成功率高于 B 组（P =0.041,〈0.05）。C 组 4只均准确命中核团。结论 MEMRI 在大鼠的视觉中枢核团立体定位中可提高定位准确性。

英文摘要：

Objective To explore the value of manganese-enhanced MRI in locating the rat visual nuclei.Methods The visual nuclei of thirty-six rats were located by 3 different ways including individual MEMRI locating （group A,n= 1 6）,anatomical atlas locating （group B,n=1 6）and direct puncture by using the data obtained in MEMRI （group C,n=4）.After unilateral intra-vitreal injection of MnCL2 （30 mmol/L×3 μL）in group A,the brain MRI was performed 24 h later.The location coordinate of lateral geniculate nucleus （LGN） and superior colliculus （SC）were recorded individually.The nuclei injections （3% fluorogold solution,1 μL）were performed by using different location coordinate in groups A and B.The rat’s retinas were examined under fluorescence microscope 5 days later,and the results were compared between the two groups.After brain nucleus puncture injection （30 mmol/L MnCL2 solution,0.5 μL）,MRI was performed 1 h later in group C.Results The success rate was 93.8% （1 5/1 6）in group A,and 65.5% （10/1 6）in group B.The difference between groups was statistically significant （P〈0.05）.All the injection locations of C group were agreed with atlas.Conclusion MEMRI in the visual nucleus stereotactic can improve the accuracy of location.