Sharma Bhamini, Mittal Amit, Sharma Rahul, Rai Pinki, Aulakh Kirandeep K
Anatomy, Maharishi Markandeshwar Institute of Medical Science & Research, Ambala, IND.
Radiodiagnosis, Maharishi Markandeshwar Institute of Medical Science & Research, Ambala, IND.
Cureus. 2024 Nov 19;16(11):e73991. doi: 10.7759/cureus.73991. eCollection 2024 Nov.
White matter tracts that connect different parts of the brain comprise the structural connectome, which is essential to its operation. Assessing behavioral changes and brain health requires an understanding of these tracts. Diffusion tensor imaging (DTI), in particular, allows for the thorough viewing and characterization of these routes in tractography. In order to assess the impact of aging on white matter integrity, this study examines the 10 main white matter tracts in men, paying particular attention to volume, fractional anisotropy (FA), and mean diffusivity (MD).
A cohort of 49 men aged 18-50 years was examined using a Philips Multiva 1.5T MRI. DTI scans were performed after obtaining informed consent. Participants with neuronal disorders were excluded. Ten tracts were assessed: inferior fronto-occipital fasciculus (IFOF), superior fronto-occipital fasciculus (SFOF), inferior longitudinal fasciculus (ILF), superior longitudinal fasciculus (SLF), cingulum, corticospinal tract (CST), forceps major, forceps minor, uncinate fasciculus, and anterior thalamic radiation (ATR). Statistical analysis employed Kruskal-Wallis tests to compare age groups.
Significant age-related differences were observed in the IFOF, which exhibited notable changes in both volume and MD. Specifically, the IFOF's volume peaked in the 31-40 age group (14.42 ± 6.05) and declined in the 41-50 age group (8.71 ± 5.07), with a statistically significant p-value of 0.019. In parallel, MD increased significantly with age, moving from 0.86 ± 0.08 in the 18-30 group to 1.09 ± 0.13 in the 31-40 group and stabilizing at 0.96 ± 0.12 in the 41-50 group (p < 0.001). Notably, while the FA values remained relatively stable across age groups (p = 0.063), the increase in MD suggests a decline in neural efficiency or potential myelin degradation. Other tracts, including the SFOF and SLF, displayed stability in volume, FA, and MD across age groups, indicating a degree of resilience in certain neural pathways.
This study highlights the utility of tractography in understanding age-related changes in white matter, such as in Alzheimer's disease, age- and sex-related abnormalities, and dementia, particularly emphasizing the IFOF's sensitivity. Findings offer insights into brain connectivity and neurological health, indicating a need for further contribution to inform interventions aimed at cognitive preservation.
连接大脑不同部位的白质束构成了结构连接组，这对大脑的运作至关重要。评估行为变化和大脑健康需要了解这些白质束。特别是扩散张量成像（DTI），能够在纤维束成像中全面观察和描述这些纤维束。为了评估衰老对白质完整性的影响，本研究考察了男性的10条主要白质束，特别关注其体积、分数各向异性（FA）和平均扩散率（MD）。
使用飞利浦Multiva 1.5T磁共振成像仪对49名年龄在18至50岁的男性进行了检查。在获得知情同意后进行DTI扫描。排除患有神经疾病的参与者。评估了10条纤维束：额枕下束（IFOF）、额枕上束（SFOF）、下纵束（ILF）、上纵束（SLF）、扣带、皮质脊髓束（CST）、胼胝体压部、胼胝体膝部、钩束和丘脑前辐射（ATR）。采用Kruskal-Wallis检验进行年龄组间的统计分析。
在IFOF中观察到了与年龄相关的显著差异。其在体积和MD方面均表现出明显变化。具体而言，IFOF的体积在31至40岁年龄组达到峰值（14.42±6.05），在41至50岁年龄组下降（8.71±5.07），p值为0.019，具有统计学意义。同时，MD随年龄显著增加，从18至3岁年龄组的0.86±0.08增加到31至40岁年龄组的1.09±0.13，并在41至50岁年龄组稳定在0.96±0.12（p<0.001）。值得注意的是，虽然FA值在各年龄组中相对稳定（p=0.063），但MD的增加表明神经效率下降或可能存在髓鞘降解。其他纤维束，包括SFOF和SLF，在各年龄组的体积、FA和MD方面均表现稳定，表明某些神经通路具有一定的弹性。
本研究强调了纤维束成像在理解白质与年龄相关变化方面的作用，如在阿尔茨海默病、年龄和性别相关异常以及痴呆症中的变化，尤其强调了IFOF的敏感性。研究结果为大脑连接性和神经健康提供了见解，表明需要进一步研究以为旨在保护认知功能的干预措施提供信息。
