Abstract
Purpose :
Prior cross-sectional studies have revealed decreased macular perfusion density (PFD) and increased peripapillary capillary PFD in Parkinson’s disease (PD). We assess longitudinal rate of change of retinal microvascular and structural parameters in PD vs controls with normal cognition.
Methods :
Subjects were imaged using Zeiss Cirrus HD-5000 AngioPlex. Those with confounding medical or ocular comorbidities were excluded and image quality was manually reviewed. Superficial capillary plexus PFD, vessel density (VD), and foveal avascular zone (FAZ) were assessed using ETDRS 6x6 zones (circle, inner ring, outer ring), and 3x3 zones (circle, inner ring). PFD, VD, FAZ, peripapillary retinal nerve fiber layer (RNFL) thickness, ganglion cell-inner plexiform layer (GC-IPL) thickness, and central subfield thickness (CST) were measured at 2 time points roughly 1 year apart. Rate of change was calculated per year and compared between groups using generalized estimating equations.
Results :
74 eyes of 40 patients with PD (60% male, mean age 67.4±7.9 years) & 149 eyes of 78 controls (28% male, mean age 70.3±5.8 years) were included. No demographic differences were observed between groups except a higher proportion of females in controls (p=.001). PD had a greater decline in PFD in the 6x6 circle (mean change per year in PD= –0.021, control=0.00; p=.001), 6x6 inner ring (PD= –0.018, control=0.001; p=.007), 6x6 outer ring (PD= –0.022, control=0.00; p=.001), 3x3 circle (PD= –0.016, control=0.002; p<.001), 3x3 inner ring (PD= –0.016, control=0.002; p<.001). PD had greater decline in VD in the 6x6 circle (mean change per year in PD= –.072/mm, control= –0.054/mm; p=.006), 6x6 inner ring (PD= –0.636/mm, control= –0.048/mm; p=.03), 6x6 outer ring (PD= –0.746/mm, control= –0.054/mm; p=.005), 3x3 circle (PD= –0.939/mm, control=0.006/mm; p<.001), 3x3 inner ring (PD= –0.942/mm, control=0.013/mm; p<.001). PD had greater decrease in GC-IPL thickness (mean change per year in PD= –0.403µm, control=0.128µm; p=.01). There were no significant differences in rate of change in FAZ, CST, RNFL thickness, and no significant differences in rate of change when stratified by PD severity.
Conclusions :
PD may be associated with more rapid loss of retinal microvascular perfusion and vessel density, and more rapid thinning of the GC-IPL compared to normal aging in healthy controls with normal cognition.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.