Objective: To investigate the relevance of the clinical finding of bulging eyes (BE) in a large Brazilian cohort of spinocerebellar ataxias (SCA), to assess its importance in clinical differential diagnosis among SCA.
Methods: Three hundred sixty-nine patients from 168 Brazilian families with SCA were assessed with neurological examination and molecular genetic testing. BE was characterized by the presence of eyelid retraction. Genetically ascertained SCA3 was detected in 167 patients, SCA10 in 68 patients, SCA2 in 20, SCA1 in 9, SCA7 in 6, and SCA6 in 3 patients.
Results: BE was detected in 123 patients with SCA (33.3%), namely 109 of the 167 SCA3 patients (65.3%) and in 5 of the others SCA patients (1 SCA10 patient, 2 SCA1 patients and 2 SCA2 patients).
Conclusion: BE was detected in the majority of patients with SCA3 (65.3%) and could be used with a clinical tool for the differential diagnosis of SCA.