Eye manifestations in Huntington's disease: an update on the potential of ocular biomarkers

Huntington's disease (HD) remains a devastating neurodegenerative disorder caused by CAG repeat expansion in the HTT gene. Biomarkers are urgently needed to facilitate more accurate evaluation of disease onset, progression, and response to interventions. Characteristic clinical features of the disease are secondary to neuronal dysfunction, and the eye provides a potential window to characterize these changes. In this review, we systematically evaluate clinical studies examining ocular abnormalities in HD, including oculomotor function and retinal anatomy assessed by optical coherence tomography. Findings indicate that while ocular abnormalities can be identified in HD, their clinical utility remains unclear. Further evaluation in large cohorts of gene-positive individuals followed longitudinally is required.