基于MRI的早期盲人海马体积分析研究

Volume analysis of the hippocampal formation in early blind subjects based on MRI

目的:采用3.0T磁共振对早期盲人与视力正常人的海马结构进行定量测量,探讨早期盲人与视力正常人之间海马结构的体积差异。方法:对早期盲人与视力正常人各22例行颅脑MRI扫描,获得3D-T1WI图像并对每个个体的两侧海马进行手动分割,测量海马体积并比较两组之间海马体积整体及前、中、后部体积差异。结果:早期盲人组及视力正常组的海马均有半球差异,表现为右侧海马总体积明显大于左侧,差异有统计学意义(P<0.05)。视力正常组左、右侧海马总体积大于早期盲人组,差异有统计学意义(P<0.05);且早期盲人组右侧海马后部和左侧海马中部体积小于视力正常组,差异有统计学意义(P<0.05)。结论:早期盲人组及视力正常组的右侧海马总体积均大于左侧,与视力正常组相比早期盲人组双侧海马总体积明显缩小,以右侧海马后部和左侧海马中部为著。

Objective: To investigate the difference of hippocampal volume between early blind subjects and normal sighted controls by using 3.0T MR scanner. Methods: Twenty-two early blind subjects and an equal number of sighted controls were underwent 3D T 1-weighted scanning using GE 3.0T MR scanner.The bilateral hippocampi were manually segmented and the volumes of them were automatically calculated using ITK-SNAP and MATLAB software,respectively.The difference of whole hippocampal volume between the two groups were compared.Meanwhile,the volumes of anterior,middle and posterior parts of the hippocampus between the two groups were also compared. Results: The volumes of the hippocampal formation were statistically lager in right than in left in both groups ( P <0.05),indication a hemisphere difference.Compared with early blind subjects,the bilateral hippocampal volumes of normal sighted controls were statistically larger ( P <0.05).Moreover,the right posterior and the left middle parts of the hippocampus in blind group were significantly smaller than those of normal sighted controls. Conclusion: The whole volumes of right hippocampal were larger than those of the left side in both two groups.Volumes of bilateral hippocampus are substantially decreased in early blind group,which mostly involved the right posterior and the left middle parts of the hippocampus.