We read with interest the article on multiple system atrophy (MSA) by Colosimo et al1 that appeared in the March 1995 issue of the Archives and completely agree with them about the clinical criteria used for the diagnosis of possible or probable MSA. However, we believe that the contribution offered by magnetic resonance imaging (MRI) cannot now be disregarded. The studies we made at the Istituto Nazionale Neurologico "C. Besta," Milan, Italy, on the neuroradiologic aspects of MSA2-4 and on the correlations between the clinical presentation and the findings from an MRI in a large series of patients with MSA, including the varieties of striatonigral degeneration and olivopontocerebellar atrophy,5,6 clearly demonstrate the great value of MRI in the diagnosis of MSA.
In striatonigral degeneration, low-signal intensity in T2-weighted images at high-field intensity MRI (1.5 T) can be demonstrated in the putamen, principally in the posterolateral