Voxel-based Relaxometry of transverse relaxation rate with gradient echo R2(*) in patients with multiple system atrophy.

OBJECTIVE To explore the transverse relaxation rate with gradient echo R2(*) changes in patients with Parkinsonian variant of multiple system atrophy (MSA-P) with a voxel-based analysis of R2(*) map. METHODS Whole brain structural images and multi-echo T2(*) weighted image were acquired in 27 patients with probable MSA-P and 24 healthy individuals. R2(*) maps of the MSA-P were compared with the controls by voxel-based methods. RESULT Compared with the controls, MSA-P patients showed significant R2(*) decrease bilaterally in brain stem, cerebellar hemispheres, insular lobe, temporal lobes, caudate nucleus, and corpus callosum (P<0.005). CONCLUSIONS R2(*) can reveal the significant brain involvements of MSA-P. The introduction of gradient echo may increase the sensitivity, although the susceptible artifact may interfere the detection efficiency of R2(*).