Objective To observe the relationship between position of normal central fixation and the position of the optic disc, and to find out the features of stability of fixation. Methods The position of central fixation of 120 eyes of 60 healthy adults was determined by MP-1 microperimeter. The position of central fixation relative to the position of the optic disk was measured. The relationship between the central fixation and the age or refraction was analyzed statistically. The difference between the right and left eye in each individual was analyzed with t test. R esul ts The central fixation located at the retina with the horizontal distance of 14.48 deg; plusmn;1.85 deg; and vertical distance of －2.14 deg; plusmn;1.26 deg; from the temporal edge of the optic disk. In the 120 eyes, 90% of the central fixation located in a bivariate normal ellipse. The normal eyes usually kept in a slightly moving condition when a normal person fixing on a subject. The median of horizontal and vertical deviation was 0.4 deg; and 0.3 deg; respectively. Conclusion The distribution of central fixation in healthy adults is a bivariate normal ellipse. When fixing on a subject, the moving extent of the eyes in the horizontal direction is larger than that in the vertical direction.
Citation： LI Gaiyun,JIA Yading,ZHANG Mianhua. Position of central fixation of normal adults detected by microperimetry. Chinese Journal of Ocular Fundus Diseases, 2007, 23(6): 398-400. doi: Copy