Faculty Bibliography

PURPOSE/UNASSIGNED:To describe the utility of fundus autofluorescence (FAF) for detection and monitoring of acute regional outer retinopathy in punctate inner choroidopathy (PIC). DESIGN/UNASSIGNED:Multimodal imaging case series. METHODS/UNASSIGNED:Patients with PIC and acute regional hyperautofluorescence were identified. Multimodal imaging, treatment, and clinical course were reviewed. RESULTS/UNASSIGNED:Six eyes of five patients were included (5 women, mean age 39 years, range 28-69). All endorsed new symptoms. Short-wave blue FAF revealed regional hyperautofluorescence in the symptomatic eye, corresponding to ellipsoid zone (EZ) loss on optical coherence tomography (OCT). All patients were treated with local or systemic corticosteroids or immunosuppression, with resolution of symptoms and acute imaging abnormalities. CONCLUSIONS/UNASSIGNED:Symptomatic acute regional outer retinopathy in PIC, manifesting as hyperautofluorescence and EZ loss, is easily identifiable using widefield FAF imaging. Treatment resulted in resolution of symptoms and imaging findings in our cohort, and should be considered in this patient population.

Metformin is one of the most prescribed drugs in the world giving potential health benefits beyond that of type 2 diabetes (T2DM). Emerging evidence suggests that it may have protective effects for retinal/posterior segment diseases including diabetic retinopathy (DR), age-related macular degeneration (AMD), inherited retinal degeneration such as retinitis pigmentosa (RP), primary open angle glaucoma (POAG), retinal vein occlusion (RVO), and uveitis. Metformin exerts potent anti-inflammatory, antiangiogenic, and antioxidative effects on the retina in response to pathologic stressors. In this review, we highlight the broad mechanism of action of metformin through key preclinical studies on animal models and cell lines used to simulate human retinal disease. We then explore the sparse but promising retrospective clinical data on metformin's potential protective role in DR, AMD, POAG, and uveitis. Prospective clinical data is needed to clarify metformin's role in management of posterior segment disorders. However, given metformin's proven broad biochemical effects, favorable safety profile, relatively low cost, and promising data to date, it may represent a new therapeutic preventive and strategy for retinal diseases.

PURPOSE OF REVIEW/OBJECTIVE:The gut microbiome, trillions of microorganisms residing in our digestive tract, is now believed to play a significant role in retinal diseases. Breakthroughs in computational biology and specialized animal models have allowed researchers not only to characterize microbes associated with retinal diseases, but also to provide early insights into the function of the microbiome in relation to biological processes in the retinal microenvironment. This review aims to provide an update on recent advances in the current knowledge on the relationship between the gut microbiome and retinal disorders. RECENT FINDINGS/RESULTS:Recent work demonstrates distinct gut microbial compositions associated with retinal diseases such as agerelated macular degeneration and retinopathy of prematurity. Currently, it is believed that gut dysbiosis leads to increased gut permeability, elevated circulation of bacterial products, microbial metabolites and inflammatory mediators that result in immune dysregulation at distant anatomic sites including the retina. SUMMARY/CONCLUSIONS:Emerging evidence for the gut-retina axis can elucidate previously unknown pathways involved in retinal diseases and also presents an exciting potential therapeutic avenue. Further preclinical and clinical studies are necessary to establish causation and delineate the precise relationship of the gut microbiome with retinal disorders.