General description

Spinocerebellar ataxia 2 (SCA2) is an autosomal dominant neurodegenerative disease that occurs in young to middle age and is caused by a CAG repeat in the Ataxin 2 gene.

The progression of imaging findings is slower than in Multiple system atrophy (MSA) but faster than in Spinocerebellar ataxia 3 (SCA3). Imaging findings resemble those of MSA, but the onset is earlier than in MSA.

Parkinsonism

Symptoms include slowly progressive cerebellar ataxia, decreased tendon reflexes, pyramidal tract disturbances, and Parkinsonism. SCA 2 is often young-onset and slowly progressive, although it must be differentiated from MSA in that it also produces Parkinsonism.

Although the clinical significance is still not entirely clear, DaT scans and neuromelanin imaging show degeneration of the nigrostriatal axis.

References

1. Kurokawa, Ryo, et al. "Clinical and neuroimaging review of triplet repeat diseases." Japanese Journal of Radiology 41.2 (2023): 115-130.
2. Cocozza, Sirio, et al. "Conventional MRI findings in hereditary degenerative ataxias: a pictorial review." Neuroradiology 63.7 (2021): 983-999.