Visual dysfunction and its correlation with retinal changes in patients with Parkinson disease

Abstract

PurposeTo evaluate visual dysfunction and its correlation with structural changes in the retina in patients with Parkinson disease (PD).MethodsPatients with PD (n = 37) and controls (n = 37) underwent visual acuity (VA), color vision (using the Farnsworth and L´Anthony desaturated D15 color tests), and contrast sensitivity vision (CSV; using the Pelli Robson chart and CSV 1000E test) evaluation to measure visual dysfunction. Structural measurements of the retinal nerve fiber layer (RNFL), and macular and ganglion cell layer (GCL) thicknesses were obtained using spectral domain optical coherence tomography (SD‐OCT). Comparison of obtained data and correlation analysis between functional and structural results were performed.ResultsVA (in all different contrast levels) and all CSV spatial frequencies were significantly worse in PD patients than in controls (P < 0.05). Color vision was significantly affected (p < 0.05) based on the L´Anthony color test. Macular thinning was detected in the central, outer (inferior and temporal), and superior sectors (p < 0.05), and the RNFL had significant thinning in the temporal quadrant (p < 0.05). Significant GCL loss was observed in the superior and superonasal sectors and the GCL + minimum inner plexiform layer (p < 0.05). CSV was the functional parameter most strongly correlated with structural measurements in PD. Color vision was associated with most GCL measurements. Macular thickness was strongly correlated with macular volume and functional parameters (r > 0.70, p < 0.05).ConclusionPatients with PD had visual dysfunction that correlated with structural changes evaluated by SD‐OCT. Macular and GCL measurements may be reliable indicators of visual impairment in PD patients.