Exploring Tractography: An Analysis of Brain Connectivity Patterns in Men

Introduction: 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).

Materials and methods: 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.

Results: 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.

Conclusion: 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.