Abstract
Purpose::
To describe the relationship between early changes of optic disc deviation and peripapillary crescent formation in mild or moderate myopic eyes.
Methods::
We retrospectively evaluated series of fundus photographs periodically taken from 10 patients with mild or moderate myopia. Patients' foveas and optic disc margins were clearly identified on the photographs. Patients with high myopia and myopic macular degeneration were excluded. The distance between the fovea and the temporal edge of the optic disc was measured in each photograph and the chronological elongation of the distance between them in the same patient was regarded as optic disc deviation. Correlation between the optic disc deviation (0 to 34.5 % disc diameter) and either the progression of myopia (-0.75 to 6.25 D) or follow-up periods (21 to 98 months) was statistically examined.
Results::
Significant correlation was found between the optic disc deviation and progression of myopia (p < 0.0001) while no correlation was detected between disc deviation and follow-up periods. As optic disc deviation progressed, peripapillary crescent became larger. The series of the same patients' photographs revealed that the temporal edge of temporal crescents corresponded to the initial temporal margin of the optic disc photographically recorded before myopia progressed.
Conclusions::
We observed that optic disc appeared to deviate mostly nasally as myopia progressed and that peripapillary crescent is formed as a result of myopic optic disc deviation in mild or moderate myopic eyes.
Keywords: myopia • optic disc • clinical (human) or epidemiologic studies: natural history