骨架化弥散指数在识别年龄相关鼠脑微结构改变中的应用效果  

Skeletonized diffusion indexes identify age-related microstructural alteration in mouse brain

作　　者：袁健瑜 梁铭垚 何祎 单鸿[1,2,3] Yuan Jianyu;Liang Mingyao;He Yi;Shan Hong(Molecular Imaging Center,the Fifth Affiliated Hospital Sun Yat-sen University;Guangdong Provincial Molecular Imaging Engineering Technology Research Center;Guangdong-Hong Kong-Macao University Joint Laboratory of Interventional Medicine,the Fifth Affiliated Hospital of Sun Yat-sen University,Guangdong Zhuhai 519000,China)

机构地区：[1]中山大学附属第五医院分子影像中心 [2]广东省分子影像工程技术研究中心 [3]广东省介入医学粤港澳高校联合实验室,广东珠海519000

出　　处：《中华介入放射学电子杂志》2024年第2期114-119,共6页Chinese Journal of Interventional Radiology：electronic edition

基　　金：国家高层次青年人才项目(RLZY20231001-01)。

摘　　要：目的探究骨架化弥散指数能否灵敏检测鼠脑年龄相关微结构变化,并进一步探讨小鼠性成熟到体成熟阶段神经可塑性。方法运用弥散张量成像(diffusion tensor imaging,DTI)扫描8周龄和12周龄小鼠,基于ANTs(advanced normalization tools)改良基于纤维束追踪的空间统计(tract-based spatial statistics,TBSS)分析小鼠白质骨架,并首次使用骨架化平均扩散率的峰宽(peak width of skeletonized mean diffusivity,PSMD)评估小鼠年龄相关的白质微结构特征。结果在大部分白质纤维束中,如前连合、胼胝体前部和膝部等,体成熟小鼠各向异性分数(fractional anisotropy,FA)显著高于性成熟小鼠(P<0.05)。在小鼠胼胝体体部中间区域、扣带回区域,体成熟小鼠FA明显下降(P<0.05)。体成熟小鼠PSMD稳定增加(P<0.001)。结论骨架化弥散指数能敏感地识别出性成熟到体成熟小鼠脑微结构改变,提示性成熟后白质束仍有髓鞘形成,神经纤维进一步成熟。Objective To investigate the sensitivity of skeletonized diffusion indexes in detecting age-related microstructural alteration in the mouse brain and to evaluate the neurostructural plasticity of mouse brain from sexual to body maturity.Methods Diffusion tensor imaging(DTI)was used to scan 8-week-old and 12-week-old mice.White matter skeleton was analyzed by tract tracing-based spatial statistics(TBSS)based on advanced normalization tools(ANTs).The peak width of the skeletonized average diffusivity(PSMD)was used to assess age-related white matter microstructural characteristics in mice.Results In mature mice,numerous white matter fiber tracts,including the anterior commissure,as well as the anterior and genu of the corpus callosum,exhibited significantly higher fractional isotropy(FA)compared to those in sexually mature mice(P<0.05).Conversely,within the middle of the body of the corpus callosum and the cingulate cortex,a notable reduction in FA was observed in mature mice(P<0.05).Furthermore,the peak width of skeletonized mean diffusivity(PSMD)demonstrated a consistent increase in body mature mice(P<0.001).Conclusion The skeletonized diffusion index can identify age-dependent microstructural changes in the mouse brain,suggesting that myelination of white matter tracts and further maturation of nerve fibers occur from sexual to full body maturity.

关 键 词：弥散张量成像 基于纤维束追踪的空间统计 骨架化平均扩散率的峰宽 

分 类 号：R285.5[医药卫生—中药学]