Figure 10.

Examples of fixation stability obtained from 33 5- to 9-year-old children with hyperopic anisometropia using the Nidek MP-1 microperimeter.(Birch et al., 2012) On each image, the small blue dots mark the location of the 750 fixation points acquired during the 30 sec test period. The Nidek MP-1 calculated three ellipses to describe the areas that enclose 68%, 95%, and 99% of the fixation points; the 95% BCEA ellipse is highlighted in yellow. On the left is a child with steady fixation; only small amplitude drifts and microsaccades were present and nearly all of the fixation points fell inside of the 1 deg fixation circle shown in red (BCEA = 0.8 deg²). In the center is a more typical anisometropic child, who shows moderate fixation instability (BCEA = 5.9 deg²). On the right, a child with substantial fixation instability is shown (BCEA = 10.8 deg²).