Abstract
Purpose :
To assess changes in outer plexiform layer (OPL) of the retina in aging and age-related macular degeneration (AMD) using spectral-domain optical coherence tomography (SD-OCT).
Methods :
Comparative study of 76 eyes with non-advanced dry AMD, 14 drusen non-AMD, 12 geographic atrophy (GA), 22 old and 25 young normal controls. OPL, outer nuclear layer (ONL) and inner nuclear layer (INL) thicknesses were assessed in 12 quadrants of three annuli (inner 400-1000 mm, middle 1000-2000 mm and outer 2000-3000 mm) of central 3 mm perifoveal region. Generalized linear models were performed.
Results :
Significant thinning of the OPL was noted in the central 3 mm area in aging (35.7 ± 1.7 mm in old vs 44.8 ±1.6 mm in young (p< 0.001)) especially in the temporal and superior quadrants of the outer and middle annulus. Further thinning of the OPL and extension of the thinning into the inner annulus as small drusen developed. In the early stages of AMD, the OPL thinning were confined to the nasal and temporal quadrants of the inner annulus with the mean thickness of 28.5 ±1 mm in AMD vs 35.2 ±1.9 mm in controls in the temporal quadrant of the inner annulus (p value <0.006). OPL thinning was also present in the nasal quadrant of the inner annulus in the non-involved eye of patients with unilateral AMD. ONL thickness was significantly decreased in the superior quadrant of the inner and middle annulus in intermediate vs early AMD (74.9 ±2.8 mm in intermediate vs 87.5 ±3.8 mm in early AMD in the superior quadrant of middle annulus (p=0.003)). INL did not show any significant change.
Conclusions :
Changes in the OPL thickness happen in aging and may precede drusen in AMD. These findings suggest that pathologic neurosensory retina changes in AMD are more prominent than that seen by clinical examination.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.