A recent study based in California used SD-OCT to confirm risk factors for macular atrophy development that were originally identified with color fundus photography (CFP) and fluorescein angiography (FA). Using three-dimensional detection methods provided a more accurate description of the baseline characteristics, the researchers noted in their paper.

The retrospective analysis included 1,097 patients with subfoveal choroidal neovascularization secondary to wet AMD treated with intravitreal ranibizumab 0.5mg. The researchers identified an increased risk of atrophy with the presence of intraretinal cysts, type 3 neovascularization and macular atrophy in the fellow eye. Presence of subretinal fluid was associated with a lower rate of atrophy development.

OCT analysis revealed five new baseline risk factors for macular atrophy: higher central drusen volume (within central 3mm), lower choroidal thickness, presence of nascent atrophy, presence of reticular pseudodrusen and increased central foveal thickness.

The study did note that neither monthly ranibizumab treatment nor quadrupling the dose of ranibizumab increased the risk of macular atrophy development at 24 months. The researchers believe these results suggest the atrophy observed is more likely related to natural progression of the underlying AMD rather than any direct effect of treatment. Also, the risk factors for macular atrophy development appeared to overlap with risk factors for geographic atrophy development.

“The current analysis of OCT data is more robust than CFP or FA data assessments and provides a more comprehensive depiction of macular atrophy risk factors,” the study concluded. “OCT is nearly universally obtained in patients with wet AMD undergoing anti-VEGF therapy and may be useful in patient prognostication.”

Sadda SR, Abdelfattah NS, Lei J, et al. SD-OCT analysis of risk factors for macular atrophy development in the HARBOR Study for neovascular age-related macular degeneration. Ophthalmology. April 2, 2020. [Epub ahead of print].