Figure 1.

Method overview using study eye 7. (A) The foveal-BMO (FoBMO) axis (Fig. 2) is determined and defined to be the nasal-temporal axis of the ONH 3D histomorphometric reconstruction (3D HMRN) (relative to the embedded orientation [EO] of the tissues [embedded vertical axis depicted by blue line]) by colocalizing the reconstructed vessels to a fundus photo (fovea not shown; see Fig. 2). Lamina is isolated (not shown); the beams are segmented (B) (Fig. 3); and each beam voxel and pore voxel has the associated diameter values assigned (Fig. 4). (C) Each voxel is then translated to a common cylinderized space (Figs. 5, 6). (D) The cylinder is rotated to establish FoBMO-oriented 30° (centered on the clinical clock-hours) sectors that straddle the FoBMO nasal-temporal and superior-inferior axes. All left eye data are converted into right eye orientation (Fig. 7). The three principal laminar microarchitecture outcome parameters are (E) beam diameter (BD) (with right eye, clock-hour, 30° sector designations), (F) pore diameter (PD), and (G) connective tissue volume fraction (CTVF). Secondary volumetric outcome parameters include (H) connective tissue volume (CTV) and (I) laminar volume (LV). For all connective tissue and pore parameters, scaling is adjusted so that white suggests more and black suggests less connective tissue. Laminar volume is depicted in green because it is not related to connective tissue. All parameters are reported within 12 central and 12 peripheral FoBMO-oriented 30° sectors (D). A separate analysis considers inner (one-third), middle (one-third), and outer (one-third) laminar layers (not shown). See the appropriate Methods sections and Figures 2 through 7 for detailed explanations of each step.