Volumetric MRI Changes in Spinocerebellar Ataxia (SCA3 and SCA10) Patients

• Published in: Cerebellum (London, England) Vol. 19; no. 4; pp. 536 - 543
• Main Authors: Arruda, Walter Oleschko, Meira, Alex Tiburtino, Ono, Sergio Eiji, de Carvalho Neto, Arnolfo, Betting, Luiz Eduardo Gomes Garcia, Raskin, Salmo, Camargo, Carlos Henrique F., Teive, Hélio Afonso Ghizoni
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2020; Springer Nature B.V
• Subjects: Adult; Ataxia; Basal ganglia; Biomedical and Life Sciences; Biomedicine; Brain - diagnostic imaging; Brain - pathology; Brain stem; Cerebellum; Diencephalon; DNA Repeat Expansion; Female; Genetic screening; Globus pallidus; Humans; Machado-Joseph Disease - diagnostic imaging; Machado-Joseph Disease - pathology; Magnetic Resonance Imaging; Male; Medical imaging; Middle Aged; Neurobiology; Neuroimaging; Neurology; Neurosciences; Original Paper; Spinocerebellar ataxia; Spinocerebellar Ataxias - diagnostic imaging; Spinocerebellar Ataxias - pathology; Thalamus; Neuroimaging; Ataxins; Machado-Joseph disease; Magnetic resonance imaging; Spinocerebellar ataxias
• ISSN: 1473-4222; 1473-4230
• DOI: 10.1007/s12311-020-01137-3

Spinocerebellar ataxias type 3 (SCA3) and type 10 (SCA10) are the most prevalent in southern Brazil. To analyze the relationships between volumetric MRI changes and clinical and genetic findings in SCA3 and SCA10 patients. All patients in the study had a confirmed genetic diagnosis. Demographic data, ataxia severity (SARA score), and the size of the expanded alleles were evaluated. Nineteen SCA3 and 18 SCA10 patients were selected and compared with a similar number of healthy controls. Patient and control groups underwent the same MRI protocol. The standard FreeSurfer pipeline was used for the morphometric data. Our results show more affected brain structures (volume reductions) in SCA3 patients than in SCA10 patients (15 vs. 5 structures). Volume reductions in brain structures were also greater in the former. The main areas with significant volumetric reductions in the former were the cerebellum, basal ganglia, brain stem, and diencephalon, whereas in the latter, significant volume reductions were observed in the cerebellum and pallidum. While SARA scores and disease duration were more correlated with volume reduction in SCA10, in SCA3, the expansion length (CAGn) correlated positively with cerebellar WM, thalamus, brain stem, and total GM volumes. There was no correlation between expansion length (ATTCTn) and neuroimaging findings in SCA10. Neuroimaging results differed significantly between SCA3 and SCA10 patients and were compatible with the differences in clinical presentation, disease progression, and molecular findings.