Assessment of retinal manifestations of Parkinson’s disease using spectral domain optical coherence tomography: A study in Indian eyes

ABSTRACT

Purpose: To assess the retinal manifestations of Parkinson’s disease using optical coherence tomography. Methods: A prospective case?control study comparing 30 eyes from 15 patients with Parkinson’s disease and 22 eyes from 11 healthy age?matched controls. Total macular subfield thickness and the thickness of the ganglion cell layer, nerve fiber layer, and peripapillary retinal nerve fiber layer were measured with spectral?domain optical coherence tomography (SD?OCT). Results: The mean age of PD patients was 68.4 years ± 10.64 (range 46–82) and in the control group was 66.36 ± 5.22 (range 64–68). The average disease duration in patients with PD was 6.7 ± 2.8 years (range 2–10 years). The mean best?corrected visual acuity in PD was 20/26 and 20/20 in controls, with P = 0.0059, which was significant. Significant difference was also found in the contrast sensitivity between both groups. Structural differences in the central macular thickness (P = 0.0001), subfield thicknesses in the superior (P = 0.003), inferior (P = 0.001), nasal (P = 0.004), and temporal subfields (P = 0.017) was seen. Severe thinning of the ganglion cell layer was seen in PD patients (P = 0.000) as well as of the nerve fiber layer (P = 0.004). Peripapillary retinal nerve fiber thickness measured showed significant thinning in superotemporal (P = 0.000), superonasal (P = 0.04), inferonasal (P = 0.000), inferotemporal (P = 0.000), nasal (P = 0.000), and temporal quadrants (P = 0.000). Conclusion: Visual dysfunction was observed in patients with PD along with structural alterations on OCT, which included macular volumes, ganglion cell layer, and peripapillary retinal nerve fiber layer.