LOCATION OF THE FOVEA AT THE FUNDUS IN RELATION TO THE OPTIC-NERVE HEAD

Background: Exact determination of the location of the fovea may be di fficult, especially in patients suffering from macular pathology. The purpose of this study was to evaluate whether the distance between the optic nerve head and fovea in healthy eyes may be helpful in such pat ients. Patients and methods: We measured the distance between the cent er of the optic nerve head and the fovea in 165 healthy eyes in a hori zontal and vertical direction. Results were correlated to the refracti ve status. Results: There was a relatively high deviation between all eyes for the distance between the optic disc and the fovea (15.5 +/- 1 .2 degrees [12.8 to 21.3 degrees]). There was a significant relationsh ip between this distance and the refraction (r = 0.353, P<0.001). Intr aindividual deviation between the right and left eyes showed a markedl y lower variance (0.67 +/- 0.49 degrees [0.05 to 2.3 degrees]). Conclu sion: The distance between the optic nerve head and the fovea does not allow for meaningful determination of the location of the fovea in ey es in which morphological changes have occurred. However, knowledge of this distance from the other eye of the same patient is helpful.