Objectives: In the present study, we compared the patterns of regional cerebral blood flow (rCBF) between cerebellar variant of multiple system atrophy (MSA-C) and the late-onset cortical cerebellar ataxia (LCCA) using FineSRT.
Patients and methods: We performed (99m)Tc ethylcysteinate dimer (ECD) single-photon emission computed tomography in 11 patients with MSA-C (mean age 65.7 years), 7 patients with LCCA (mean age 62.0 years), and 12 age-matched healthy controls (mean age 64.1 years). The rCBF in the region of interest (ROI) was measured by the noninvasive Patlak plot method and calculated using FineSRT, which is a fully automated the ROI technique.
Results: All patients with MSA-C had various degrees of atrophy in the brainstem and middle cerebellar peduncles and 4 of 11 patients showed a clear 'hot cross bun' sign in pontine base on T2-weighted MR images. All patients with LCCA showed the various degrees of atrophy in cerebellum without brainstem. FineSRT revealed the significantly decreased rCBF in the caudate tail, fusiform, lingual, cerebellum, midbrain, and pons in MSA-C group compared with controls. Moreover, MSA-C group showed significantly decreased rCBF in the pons compared with LCCA group.
Conclusion: We suggest that a widespread brain involvement is present in patients with MSA-C and the decreased rCBF in the pons may support the differential diagnosis between MSA-C and LCCA.