Binocular vision disorders and tear meniscus parameters using anterior segment-optical coherence tomography (AS-OCT) in Parkinson’s disease: a case report

BACKGROUND: Ocular abnormalities are potential consequences of early signs of Parkinson’s disease (PD). The novelty of this case is that it provides additional binocular vision findings for better diagnosis and demonstrates the role of imaging techniques such as anterior segment-optical coherence tomography (AS-OCT) to quantitatively assess the ocular surface in PD. CASE PRESENTATION: A 55-year-old male with early Parkinson’s disease presented with a history of transient diplopia, irritation, and burning sensation one year after his PD diagnosis. On examination, his contrast sensitivity was reduced, and he had receded convergence amplitude, poor saccadic function, and reduced developmental eye movement (DEM) test. Additionally, his tear meniscus parameters were significantly reduced when measured quantitatively. CONCLUSION: Convergence insufficiency and eye movement deficit may serve as early oculomotor signs of PD. Imaging techniques such as AS-OCT, which quantitatively assess the ocular surface, could also serve as diagnostic tools in the early detection of underlying symptoms associated with dry eyes.