A Translational Reference for Green Autofluorescence Imaging in the Rhesus Macaque Eye using the OcuMet Beacon

Ripolles-Garcia, A.; Lim, J.; Raposo, A. C.; Bailey, J. C.; Handel, K. W.; Khan, M. J.; Sutton, L. R.; Yu, J.; Dougherty, E. K.; Nguyen Jaggers, T.; Lam, B.; Valjalo, Y. N.; Thienpaitoon, R.; Muniz, N. A.; Giorgi, E.; Villafuerte-Trisolini, C. I.; Anderson, K.; Habbas-Nimer, N.; Rich, C. A.; Riegger, K.; Moshiri, A.; Leonard, B. C.; Yiu, G.; Thomasy, S. M.

doi:10.64898/2026.08.11.744247

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bioRxiv · 10.64898/2026.08.11.744247

A Translational Reference for Green Autofluorescence Imaging in the Rhesus Macaque Eye using the OcuMet Beacon

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Abstract

PurposeTo evaluate associations between green autofluorescence (GAF) and structural and functional measures relevant to retinal and optic neuropathies, and to establish normative GAF values across the optic nerve head (ONH), macula, and papillofoveal bundle (PFB) in rhesus macaques. MethodsEighty-two macaques with normal ONH morphology by spectral-domain optical coherence tomography (SD-OCT) were included with a mean {+/-} SD age of 12.76 {+/-} 7.18 (range 0.11-29.39) years. The GAF images were acquired in the ONH, macula and PFB with the OcuMet Beacon. In a subset of macaques (n=19), pattern electroretinogram (PERG) and photopic full-field ERG including the photopic negative response (PhNR) were recorded. ResultsThe GAF significantly increased with age in the ONH, macula and PFB. After adjusting by age, there were no sex differences, but IOP showed a positive association with macular GAF. At the ONH, higher GAF correlated with thinner retinal nerve fiber layer, inner and outer segment complex, and total retinal thickness. In the macula, inner nuclear layer thickness was positively associated with GAF, whereas outer plexiform layer and inner and outer segment complex were inversely associated. The PERG amplitudes inversely tracked ONH GAF. ConclusionsGAF rises with age and IOP, couples to retinal structure, and at the ONH, aligns with inner-retinal functional indices. This study provides a regional reference for GAF in rhesus macaques. Translational RelevanceNormative GAF data in healthy rhesus macaques provide a framework for interpreting this noninvasive signal in translational studies of retinal and optic nerve disease.

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Ripolles-Garcia, A., Lim, J., Raposo, A. C., Bailey, J. C., Handel, K. W., Khan, M. J., Sutton, L. R., Yu, J., Dougherty, E. K., Nguyen Jaggers, T., Lam, B., Valjalo, Y. N., Thienpaitoon, R., Muniz, N. A., Giorgi, E., Villafuerte-Trisolini, C. I., Anderson, K., Habbas-Nimer, N., Rich, C. A., Riegger, K., Moshiri, A., Leonard, B. C., Yiu, G., Thomasy, S. M.. 2026-08-19. A Translational Reference for Green Autofluorescence Imaging in the Rhesus Macaque Eye using the OcuMet Beacon. https://doi.org/10.64898/2026.08.11.744247

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