Proton magnetic resonance spectroscopy: normal findings in the cerebellar hemisphere in childhood

Background: The cerebellar hemispheres (CER) are different from the supratentorial white and gray matter embryologically, in cytoarchitecture, and probably in metabolic activity. Proton magnetic resonance spectroscopy (H-1 MRS) can provide a noninvasive biochemical analysis of this region. Objective: To study, with H-1 MRS, metabolite concentrations in CER as a function of age and compare these metabolic data with those of parietoccipital white matter (PO WM) in healthy children. Materials and methods: Using single-voxel H-1 MRS, we studied 37 volunteers (3-18 years) with normal MRI scans of the brain. H-1 MRS was performed using the PRESS technique in CER and PO WM. The NAA/Cr, Cho/Cr, NAA/H2O, Cr/H2O, and Cho/H2O ratios were analyzed as a function of age. Metabolic data from these regions were compared. Results: The NAA/Cr ratio tended to increase with age in CER. Mean NAA/Cr and Cho/Cr ratios were found to be lower in CER than in PO WM. Mean NAA/H2O, Cr/ H2O, and Cho/H2O ratios in CER were higher than in the PO WM. Conclusion: Our data confirm the regional variations between CER and PO WM metabolite ratios, and demonstrate a tendency of age-dependent change of the NAA/ Cr ratio in CER. The creatine concentration was significantly higher in the cerebellum than in the PO WM.