Spinocerebellar ataxia in a cohort of patients from Rio de Janeiro.

OBJECTIVE: The objective of this study is to describe the first series of spinocerebellar ataxia (SCA) in Rio de Janeiro, whose population has a high proportion of mixed Portuguese and African ancestry. METHODS: We reviewed the medical records of patients with progressive ataxia evaluated at the Sarah Network of Rehabilitation Hospitals (Rio de Janeiro). Clinical course, genetic tests for hereditary ataxia, brain MRI, and electroneuromyography were analyzed. RESULTS: SCA was confirmed in 128 individuals, one-third of African descendants. SCA3 predominated (83.6%), followed by SCA7 (7%); SCA2 (3.9%); SCA1, SCA6, and SCA8 (1.6% each); and SCA10 (0.8%). Dysphagia, pyramidal signs, and neurogenic bladder occurred frequently. Oculomotor disorders occurred with SCA3, SCA7, SCA2, and SCA1; peripheral neuropathies with SCA3 and SCA1; extrapyramidal syndromes with SCA3, SCA7, and SCA2; bilateral visual impairment with SCA7; and epilepsy with SCA10. Mobility assistance was required in 75% after 11 years and wheelchair in 25%. The Scale for the Assessment and Rating of Ataxia scores at the last follow-up varied from 2 to 37 (median = 14.50) and correlated positively with duration of the disease. In SCA3, a higher CAG repeats correlated with a lower age at onset. African ethnicity was associated with earlier onset, regardless of CAG repeats. The main brain MRI abnormality was cerebellar atrophy, isolated or associated with brainstem atrophy, "hot cross bun" sign, or brain atrophy. Linear T2 hyperintensity along the medial margin of the globus pallidus occurred in SCA3, SCA2, SCA1, and SCA7. ENMG confirmed peripheral neuropathy in SCA3 and SCA1. CONCLUSION: Machado Joseph disease/SCA3 was the most frequent inherited dominant ataxia in Rio de Janeiro. This study revealed new aspects of ethnic influence in the clinical course and new MRI findings.

Scrutinizing brain magnetic resonance imaging patterns in Angelman syndrome.

BACKGROUND: Global developmental delay, lack of speech, and severe epilepsy are the characteristic hallmarks of Angelman syndrome (AS). The purpose of this study was to explore the utility of brain magnetic resonance imaging (MRI) as an ancillary tool for the diagnosis of AS. MATERIAL AND METHODS: Brain MRI images of nine laboratory-confirmed patients with AS from a neurorehabilitation center in Rio de Janeiro were reviewed. Each MRI was assessed by a set of two experienced neuroradiologists following a predefined protocol. RESULTS: The main neuroimaging findings revealed in our study were: Thinning of the corpus callosum in five patients; enlargement of lateral ventricles in four patients; and, cerebral atrophy with frontal and temporal predominance in one patient. All patients presented with an increased signal intensity in T2-weighted images and fluid-attenuated inversion recovery (FLAIR) sequences. CONCLUSION: The lack of specific changes in the brain MRI of children with AS observed in this case series rendered brain MRI a less helpful complementary test. Thus, a definitive diagnosis of AS could only be established on molecular biology that was undertaken based on the clinical suspicion of AS.