Optical Coherence Tomography Findings in Patients of Parkinson's Disease: An Indian Perspective

BACKGROUND: Parkinson's disease (PD) is one of the most common neurodegenerative movement disorders and its incidence is increasing worldwide along with population aging. Previous clinical and histologic studies suggest that the neurodegenerative process, which affects the brain, may also affect the retina of PD patients. OBJECTIVE: The objective of this study was to determine the thickness changes of retina nerve fibers and macular volume with optical coherence tomography (OCT) in PD patients. MATERIALS AND METHODS: The spectral domain OCT was used to assess the thickness of retinal nerve fiber layer (RNFL) and macular volume from 34 PD patients and 50 healthy age-matched controls. RESULTS: Compared with healthy age-matched controls, the RNFL thickness of PD patients was much thinner (P < 0.05) in all retinal quadrants, with temporal thinning being more than nasal thinning. Macular volumes were diminished in both perifoveal and outer macular regions in all sectors (P < 0.05) with preserved foveal volume. The degree of tissue loss corroborated with the severity of disease as objectively assessed by standardized rating scales (UPDRS). CONCLUSION: There is generalized retinal nerve degeneration in patients of PD and the degree of loss correlated with the severity and duration of disease.