Effect of myopia and age on optic disc margin anatomy within the parapapillary atrophy area

To evaluate the effect of myopia and age on temporal optic disc margin anatomy within the parapapillary atrophy (PPA) area by use of spectral-domain optical coherence tomography (OCT).

Fifty young myopic eyes with PPA (myopic PPA group), 50 aged non-myopic eyes with PPA (aged PPA group), and 50 young non-myopic eyes without PPA (control group) were enrolled. High-definition OCT scanning was used to obtain horizontal cross-sectional optic nerve head (ONH) images. By use of these OCT scans we investigated three temporal optic disc margin structures: the configuration of the border tissue of Elschnig; the cross-sectional ONH structure coinciding with the clinically detected optic disc margin; and the integrity of the retinal layers within the PPA area.

The distribution of the configuration of the border tissue of Elschnig and the cross-sectional ONH structure coinciding with the clinically detected optic disc margin of the myopic PPA group differed significantly from those of the control group (P < 0.01) whereas those of the aged PPA group did not (P > 0.05). Other than the photoreceptor layer, the retinal layers within the PPA area were more commonly impaired in the myopic PPA group than in the aged PPA group (P < 0.001).

Myopia and aging led to different structural changes in temporal optic disc margin anatomy within the PPA area. This finding implies that different mechanisms may underlie myopic and age-related PPA development.