Analysis of the peripapillary retinal nerve fiber layer and choroidal thickness in patients with Parkinson's disease using swept‐source optical coherence tomography

Abstract

PurposeTo analyze the thickness of several retinal layers and the thickness of the choroid in the peripapillary area in patients with Parkinson's disease (PD) using swept‐source optical coherence tomography (SS‐OCT) as a marker for neurodegenerative injury.Methods108 eyes of patients with PD and 90 eyes of healthy controls were included. All subjects underwent ophthalmologic evaluation, including retinal and choroidal assessment using SS‐OCT Triton (Topcon), 3DH Wide protocol. RNFL‐TSNIT data were analyzed in the peripapillary area, including retinal nerve fiber layer (RNFL), GCL+ layer (from RNFL to inner nuclear layer), GCL++ layer (from inner limiting membrane to inner nuclear layer) and choroidal thickness.ResultsPatients with PD revealed significant thinning in every retinal layer compared to healthy controls: average retinal thickness (280.25 ± 20.18 μm in patients vs. 288.18 ± 13.09 μm in controls; p = 0.013); inferotemporal sector of the RNFL thickness (135.08 ± 25.28 μm vs. 144.23 ± 17.19 μm; p = 0.024); superotemporal sector of the GCL+ layer thickness (38.52 ± 7.02 μm vs. 41.78 ± 9.24 μm; p = 0.047); inferotemporal sector of the GCL++ layer thickness (176.00 ± 28.07 μm vs. 187.07 ± 16.93 μm; p = 0.010). Contrary, patients with PD revealed significant thickening in total choroidal thickness compared to healthy controls (153.56 ± 62.48 μm in patients vs. 125.64 ± 52.53 μm in controls; p = 0.012), choroidal nasal (152.73 ± 50.54 μm vs. 129.32 ± 54.86 μm; p = 0.024), choroidal temporal (165.82 ± 80.16 μm vs. 128.40 ± 50.81 μm; p = 0.003) and choroidal inferior thickness (129.90 ± 64.70 μm vs. 98.83 ± 51.67 μm; p = 0.006).ConclusionsPatients with PD present significant reduction of peripapillary retinal, RNFL and ganglion cell layer thickness and significant thickening of the choroid in the peripapillary area detectable with new SS‐OCT technology.