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

PURPOSE: 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).

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.