Figure 2
Spatial topography and age-related regression analysis where relevant in the (A,B) retinal nerve fibre layer (RNFL) and (C–E) ganglion cell layer (GCL), using location-specific cluster analysis. For each layer, the (A,C) spatial cluster patterns (in right eye format), (B,D) corresponding plots of cluster thickness versus groups, i.e. sex or age interval cohorts (cyan crosses denote vertex age), and (E) corresponding age-correction regression functions, vertex ages (if within the limits of this study’s cohort), and slopes as derived after the vertex age are presented. All slopes were significantly different from zero (p < 0.05). Central black circle in the GCL represents the excluded central four grids containing the fovea. Regression characteristics are in the forms y = ax2 + bx + c (quadratic) or y = mx + c (linear), where x = age, y = thickness (µm). ‘a’, ‘b’, and ‘m’ are co-efficients, and ‘c’ is a constant. Peak thicknesses were based off the vertex age for quadratic models, or y-intercept for linear models or cases where the vertex age was beyond the age limits of this study. In cases where post-vertex age included less than three averaged data points, the nearest neighbouring data points up to three averaged totals were included to minimise variability. Mean thickness ± SD of all plotted values are provided in (Supplementary Table 9).
