Background: Parkinson's disease (PD) is known to produce alterations in dopaminergic neurons in human retina. Recent reports showed a decrease in retinal thickness and selective retinal layers.
Objective: To investigate macular and optic nerve (ON) morphology in PD comparing the eyes on the “more” or “less” affected sides and healthy controls using optical coherence tomography (OCT).
Methods: High-resolution spectral domain OCT was used to image 25 patients with PD and 25 healthy controls. RT and macular RNFL thickness and ON parameters were measured using automated software. Retinal layers segmentation analysis was performed with ImageJ.
Results: Macular segmentation analysis showed thinner retinal nerve fibre layer (RNFL) in temporal (p = 0.015) and central (p = 0.02) areas; outer nuclear layer (ONL) – in all analysed areas (p < 0.001 for all) and retinal pigment epithelium (RPE) – in nasal (p = 0.001) area and centrally (p = 0.04). Maximal optic nerve cup depth was statistically larger in PD patients with associated peripapillary RNFL thinning in all segments.
Conclusion: Our study confirms previous histological and electrophyiological findings of abnormal retina in PD. We demonstrated significant thinning of the RNFL, ONL and RPE in patients with PD. RPE thinning could be related to dopamine deficiency. We also describe for the first time optic nerve abnormalities in PD. In addition, we describe for the first time changes of the optic nerve. The macular structure in PD patients indicated the most significant difference between the eyes on the side with less severe neurological deficit and healthy controls.
© 2015 Published by Elsevier Inc.