Week in review: Brain remodeling and vision, first spray for mydriasis, unique gut microbiota in AMD

A weekly roundup of ophthalmic news from around the web.

Plasticity in the brain’s white matter allows for improvement of visual function past early childhood. Brain remodeling can enable restoration of visual skills even at later ages, according to newly published research. Nineteen patients aged 7–16 years with blindness due to congenital cataracts underwent cataract surgery and were followed up through adolescence. After visual acuity was restored, changes in the brain’s white matter, including plasticity in late-visual pathways, were identified through diffusion tensor imaging. The younger the patient was at surgery, the greater the impact of the procedure, but improvements in behavioral performance were seen in all patients. Dr. Pawan Sinha, professor of brain and cognitive sciences at Massachusetts Institute of Technology, said “Given the remarkable level of remodeling of brain structure that we are seeing, it reinforces the point that…all children ought to be provided treatment.” Massachusetts Institute of Technology; Proceedings of the National Academy of Sciences

First ophthalmic spray for mydriasis is approved. On May 8, 2023, the US Food and Drug Administration approved Mydcombi (tropicamide and phenylephrine hydrochloride ophthalmic spray 1%/2.5%) for inducement of mydriasis during diagnostic procedures and other situations where short-term dilation is needed. Developed by Eyenovia and using the novel Optejet microdose delivery platform, Mydcombi is the first fixed-dose combination spray of tropicamide and phenylephrine to receive FDA approval. Ophthalmology Times

Can the gut help to diagnose and identify AMD? Potentially, say researchers in China who studied the intestinal gut microbiota makeup of patients with AMD. When compared with healthy controls, those with AMD had less fecal bacterial diversity. The gut microbiota signatures were different in each population, and 7 enriched metabolic pathways were found in the AMD group but not the control group, most related to glycan synthesis and metabolism. The authors conclude that these findings may provide insight into potential microbial markers of AMD. Frontiers in Microbiology

If you’re older and non-White, having myopia puts you at greater risk for glaucoma. A cross-sectional study of data from more than 2.7 million California Medicare beneficiaries found that those with myopia were 2.4 times more likely to have primary open-angle glaucoma (POAG) than those without myopia. People with myopia and Hispanic, Asian, or Black ethnicity had even greater risk of POAG development (odds ratios 3.28, 2.74, and 2.60, respectively). The authors note the need to consider earlier or more frequent screening for individuals from racial and ethnic minority backgrounds, as well as to address any potential health or health care disparities that may contribute to these observations. JAMA Ophthalmology