Peripapillary crescent and related factors in highly myopic healthy eyes

Purpose: To investigate the relationship between the size of the peripapillary crescent and different ocular parameters in highly myopic healthy eyes; in addition, to determine whether the area of the peripapillary crescent enlarged significantly during one year of observation. Methods: The medical records of 49 highly myopic healthy eyes whose fellow eyes had myopic complications were reviewed. The area of the peripapillary crescent and other ocular parameters were measured initially and after one year. The changes in the area of the peripapillary crescent and their association with other ocular parameters during the natural course of the pathological myopia were determined. Results: The area of the peripapillary crescent was significantly associated with the choroidal thickness (P < 0.001), axial length (P < 0.001), and foveal thickness (P < 0.01). Stepwise regression analyses found that the factors most associated with the area of the peripapillary crescent were the choroidal thickness (P < 0.01) and the absolute nasal staphyloma height (P < 0.05). The factor most associated with the increase in the area of the peripapillary crescent was the increase in the axial length (P < 0.01). Conclusions: The size of the peripapillary crescent may be affected by changes in the axial length, the height of the posterior staphyloma, and the choroidal thickness.