To understand the variations in optic disc topography that may affect the local susceptibility
of nerve fibers to glaucomatous damage, we evaluated the correlations between optic
disc topography and selected ocular parameters in 210 normal eyes of healthy Japanese.
In the total study group, eyes with a longer axial length had a longer distance between
the disc and foveola, a larger index of ovalness and a larger disc (P < 0.01). A longer
disc-foveola distance correlated with a larger index of ovalness (P < 0.01). The optic
discs of severely myopic eyes had a considerably different structure from other eyes.
Eyes with a tilted optic disc were unique in that the area of the optic disc was not
large despite a positive correlation with long axial length (P < 0.01) a long disc-foveola
distance (P < 0.01), and a large index of ovalness (P < 0.01). Eyes with a rotated
optic disc were another special case. This eye type correlated in a contradictory
fashion with two parameters: a large axial length (P < 0.01) and a short disc-foveola
distance (P < 0.01). These findings suggest that changes in optic disc topography
or susceptibility to glaucomatous damage correlate with selected ocular parameters
but are not completely parallel.