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Background:Giant cell arteritis (GCA) is a vasculitis often revealed by visual signs. Diagnosis is challenging and urgent. Retinal angiography (RA) and MRI allow effective diagnosis. We compared those and proposed an imaging-based approach to diagnose GCA in ophthalmological practice.Methods:We conducted a retrospective study based on the data collected from patients suspected to have GCA on ophthalmological findings. Fluorescein (FA) and indocyanine green (ICG) RAs and MRI were performed and compared with final diagnosis.Results:Among the 41 patients included, 25 were diagnosed with GCA. Sensitivities and specificities of FA and ICG were not different. MRI showed a higher sensitivity and specificity. The approach consisting in performing RA followed by MRI provided a better accuracy.Conclusion:Our study shows that RA can be supplemented by MRI in a specialized center to provide the most accurate diagnosis in GCA revealed by visual signs.

The anatomical differences between the retinas of humans and most animal models pose a challenge for testing novel therapies. Nonhuman primate (NHP) retina is anatomically closest to the human retina. However, there is a lack of relevant NHP models of retinal degeneration (RD) suitable for preclinical studies. To address this unmet need, we generated three distinct inducible cynomolgus macaque models of RD. We developed two genetically targeted strategies using optogenetics and CRISPR-Cas9 to ablate rods and mimic rod-cone dystrophy. In addition, we created an acute model by physical separation of the photoreceptors and retinal pigment epithelium using a polymer patch. Among the three models, the CRISPR-Cas9–based approach was the most advantageous model in view of recapitulating disease-specific features and its ease of implementation. The acute model, however, resulted in the fastest degeneration, making it the most relevant model for testing end-stage vision restoration therapies such as stem cell transplantation.