Comparison of MRI and 123 I-FP-CIT SPECT for the evaluation of MSA-P clinical severity

The aim of the present study was to compare the efficacy of magnetic resonance imaging (MRI) and I-labeled 2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)nortropane single photon emission computed tomography ( I-FP-CIT SPECT) for determining the clinical severity of patients with multiple system atrophy with Parkinsonism (MSA-P). MRI and I-FP-CIT SPECT images from 17 patients with MSA-P as diagnosed using the Unified MSA Rating Scale part IV (UMSARS IV) score were compared. Brain MRI scans were available for all 17 patients and I-FP-CIT SPECT images were available for 12 patients. Putaminal atrophy (PA), hyperintense putaminal rim (HPR), hyperintense pons (hot cross bun sign, HCB), atrophy of the cerebellar vermis and hemisphere (cerebellar atrophy, CA) and other abnormalities were evaluated in the MRI scans. Distribution of striatal uptake (SU) and the specific binding ratio (SBR) on each side of the bilateral striatum were evaluated using I-FP-CIT SPECT images. No significant associations were observed between HPR, HCB, CA and UMSARS IV score. However, the frequency of PA increased significantly with higher UMSARS IV score (P