Feasibility of Macular Integrity Assessment (MAIA) Microperimetry in Children: Sensitivity, Reliability, and Fixation Stability in Healthy Observers.

Purpose: To assess the feasibility of macular integrity assessment (MAIA) microperimetry (MP) in children. Also to establish representative outcome measures (differential light sensitivity, fixation stability, test-retest reliability) for children without visual impairment.
Methods: Thirty-three adults and 33 children (9-12 years) were asked to perform three monocular MAIA examinations within a single session (dominant eye only).
Results: Children exhibited poorer test-retest reliability than adults for measures of both mean sensitivity (95% coefficient of repeatability [CoR95] = 2.7 vs. 2.3 dB, P = 0.036) and pointwise sensitivity (CoR95 = 6.2 vs. 5.7 dB, P < 0.001). Mean sensitivity was lower in children (27.6 vs. 29.5 dB, P < 0.001), and fixation stability was poorer (95% bivariate contour ellipse area [BCEA95] = 4.58 vs. 1.14, P < 0.001). Mean sensitivity was negatively correlated with fixation stability (r = -0.44, P < 0.001). Both children and adults exhibited substantial practice effects, with mean sensitivity improving by 0.5 dB (adults) and 0.9 dB (children) between examinations 1 and 2 (P ≤ 0.017). There were no significant differences between examinations 2 and 3 (P ≥ 0.374). Conclusions: Microperimetry is feasible in 9- to 12-year-old children. However, systematically lower sensitivities mean that the classification boundary for "healthy" performance should be lowered in children, pending development of techniques to improve attentiveness/fixation that may reduce or remove this difference. High measurement variability suggests that the results of multiple tests should be averaged when possible. Learning effects are a potential confound, and it is recommended that the results of the first examination be discarded.