A large-scale, collaborative, systems biology approach is needed to expedite the discovery of treatments for dry AMD—a leading cause of blindness among people 65 and older for which is there is no treatment—according to a report by a working group of scientists appointed by the National Advisory Eye Council (NAEC).
Development of new imaging technologies
Standard-of-care imaging for AMD diagnosis, classification of disease severity, and the evaluation of treatment efficacy currently include color fundus photographs, optical coherence tomography (OCT), and OCT-angiography.
Handa et al. suggest that new imaging technologies could help identify preclinical risk factors or currently unknown AMD subtypes that may impact disease progression and treatment efficacy by allowing physicians to see cellular and subcellular structures at different disease stages.
For example, “when used with a scanning laser ophthalmoscope and OCT, adaptive optics systems can visualize individual cones, changes in rods, RPE [subretinal pigmented epithelial], and SDD [subretinal drusenoid deposits] in dry AMD,” the researchers write.
Other novel imaging modalities suggested include polarization-sensitive OCT, fluorescence lifetime, and hyperspectral fluorescence. They note, however, that more data and larger clinical trials are needed to confirm the utility of these new imaging technologies, as existing trials have been in small study populations with variable follow-up.
“To advance our understanding, we must identify imaging biomarkers of early changes that reflect AMD pathobiology, predict disease progression and/or treatment response, and correlate with molecular markers that are relevant in both animal models and humans,” they conclude.
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