Role of Diffusion Tensor Imaging-Derived Metrics for the Assessment of Deranged Myelination in Children With...

Background Diffusion tensor imaging (DTI) is a sensitive neuroimaging modality that evaluates white matter microstructure by measuring parameters such as fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD). Alterations in these metrics can indicate myelin disruption, axonal injury, or generalized microstructural changes. This study aimed to assess white matter integrity in children with developmental delay and evaluate the diagnostic performance of DTI metrics using receiver operating characteristic (ROC) analysis. Methods A hospital-based observational study was conducted on pediatric subjects with neurodevelopmental abnormalities. DTI was performed, and FA, MD, RD, and AD were quantified across major tracts, including the genu and splenium of the corpus callosum, anterior and posterior limbs of the internal capsule, superior longitudinal fasciculus (SLF), inferior fronto-occipital fasciculus (IFOF), and frontal and parietal white matter. Age-matched controls served as the comparison group. Statistical analysis included group comparisons and ROC curve evaluation for diagnostic accuracy. Results Significant reductions in FA were observed in the genu of the corpus callosum (0.34±0.07), frontal white matter (0.31±0.06), parietal white matter (0.33±0.05), SLF (0.35±0.06), and IFOF (0.37±0.05) (p<0.01 vs. controls). RD was significantly elevated in these regions (0.92-0.97×10⁻³ mm²/s; p<0.01), consistent with demyelination or delayed myelination. MD values were diffusely elevated (1.06-1.12×10⁻³ mm²/s), supporting generalized microstructural disruption, whereas AD showed mild but non-significant changes. ROC analysis demonstrated that FA had the highest diagnostic accuracy: genu of the corpus callosum (AUC 0.89), frontal white matter (AUC 0.91), and SLF (AUC 0.88). RD and MD also showed strong discriminatory ability, while AD performed less robustly. Conclusion Reduced FA, along with elevated RD and MD, reliably reflects white matter microstructural injury in pediatric populations. ROC analysis confirmed FA as the most sensitive biomarker, with high sensitivity and specificity. DTI metrics hold strong clinical potential for the early detection of neurodevelopmental white matter abnormalities.