Background and purpose: Loss of integrity in nonlesional white matter occurs as a fundamental feature of multiple sclerosis in adults. The purpose of our study was to evaluate DTI-derived measures of white matter microstructure in children with MS compared with age- and sex-matched controls by using tract-based spatial statistics.
Materials and methods: Fourteen consecutive pediatric patients with MS (11 female/3 male; mean age, 15.1 ± 1.6 years; age range, 12-17 years) and age- and sex-matched healthy subjects (11 female/3 male; mean age, 14.8 ± 1.7 years) were included in the study. After we obtained DTI sequences, data processing was performed by using tract-based spatial statistics.
Results: Compared with healthy age- and sex-matched controls, children with multiple sclerosis showed a global decrease in mean fractional anisotropy (P ≤ .001), with a concomitant increase in mean (P < .001), radial (P < .05), and axial diffusivity (P < .001). The most pronounced fractional anisotropy value decrease in patients with MS was found in the splenium of the corpus callosum (P < .001). An additional decrease in fractional anisotropy was identified in the right temporal and right and left parietal regions (P < .001). Fractional anisotropy of the white matter skeleton was related to disease duration and may, therefore, serve as a diagnostic marker.
Conclusions: The microstructure of white matter is altered early in the disease course in childhood multiple sclerosis.