Gray matter T2 hypointensity is related to plaques and atrophy in the brains of multiple sclerosis patients

Cortical and subcortical gray matter hypointensities on T2-weighted MR imag es (T2WI) occur commonly in MS brains and have been related to disease dura tion, clinical course, and the level of neurologic disability. These hypoin tensities have been reported to occur in the thalamus, basal ganglia, and r olandic cortex. We assessed whether T2 hypointensity is associated with the severity of white matter plaques and atrophy of MS brains. In 114 MS patie nts, hypointensity of the thalamus, putamen, caudate, and sensorimotor cort ex was ordinally rated against age- and gender-matched normal controls on 1 .5-T R IRI fast spin-echo axial T2WI. Regional and global T2 hyper-intense and T1 hypointense parenchymal lesion loads were ordinally rated. Enlargeme nt of subarachnoid and ventricular spaces (atrophy) was ordinally rated vs. age- and gender-matched normal controls. T2 hypointensity was highly, posi tively correlated with many other MRI variables. Regression modeling showed that T2 hypointensity was related to total atrophy, total T2 lesion load, third ventricular enlargement, par ictal atrophy, and to a lesser extent, f rontal T1 lesions and cerebellar T2 lesions, but not related to gadolinium enhancement. Ordinal ratings of T2, lesions and central atrophy showed high correlations with quantitative computerized assessments. We conclude that gray matter hypointensity on T2WI may reflect pathologic iron deposition an d brain degeneration in MS. This T2 hypointensity is associated with blain atrophy and other MR markers of tissue damage. Further study is warranted t o determine if T2 hypointensity is predictive of disease course in MS and i s a useful surrogate outcome measure in therapeutic trials. (C) 2001 Elsevi er Science B.V. All rights reserved.