%0 Journal Article
%T Retinal Ganglion Cell Content Underlying Standard Automated Perimetry Size I to V Visual Sensitivities in the Non-Human Primate Experimental Glaucoma Model.
%A Venkata Srinivasan V
%A Carter-Dawson L
%A Patel NB
%J Invest Ophthalmol Vis Sci
%V 65
%N 8
%D 2024 Jul 1
%M 38995114
%F 4.925
%R 10.1167/iovs.65.8.22
%X UNASSIGNED: To determine the relationship between visual sensitivities from white-on-white Goldmann size I to V stimuli and the underlying retinal ganglion cell (RGC) content in the non-human primate (NHP) experimental glaucoma model.
UNASSIGNED: Normative data were collected from 13 NHPs. Unilateral experimental glaucoma was induced in seven animals with the least variable fields who were monitored using optical coherence tomography and 30-2 full-threshold standard automated perimetry (SAP). At varying endpoints, animals were euthanized followed by perfusion fixation, and 1-mm retinal punches were obtained from 34 corresponding SAP locations. RGCs were immunolabeled with an antibody against an RNA-binding protein (RBPMS) marker and imaged using confocal microscopy. RGC counts from each location were then related to visual sensitivities for each stimulus size, after accounting for ocular magnification.
UNASSIGNED: At the endpoint, the circumpapillary retinal nerve fiber layer thickness for experimental glaucoma eyes ranged from 47 to 113 µm. RGC density in control eyes was greatest for the 4.24° sample (18,024 ± 6869 cells/mm2) and decreased with eccentricity. Visual sensitivity at each tested location followed that predicted by spatial summation, with the critical area increasing with eccentricity (slope = 0.0036, R2 = 0.44). The relationship between RGC counts and visual sensitivity was described using a two-line fit, where the intercept of the first segment and hinge points were dependent on eccentricity.
UNASSIGNED: In NHPs, SAP visual thresholds are related to the underlying RGCs. The resulting spatial summation based structure-function model can be used to estimate RGC content from any standard white-on-white stimulus size.