Laser Speckle Flowgraphy (LSFG) in Age-Related Macular Degeneration and Diabetic Retinopathy: A Systematic Review of Recent Literature

Background: Laser Speckle Flowgraphy (LSFG) is a non-invasive imaging technology that quantitatively evaluates retinal and choroidal blood flow by analyzing speckle patterns generated by laser light scattering. This systematic review summarizes the application of LSFG in two major degenerative retinal diseases: age-related macular degeneration (AMD) and diabetic retinopathy (DR). Methods: A comprehensive literature search (2010–2025) was conducted in PubMed, Cochrane Library and EMBASE according to PRISMA guidelines. Twenty-three studies including a total of 974 eyes (191 AMD, 783 DR) were analyzed. Results: In AMD, LSFG detected baseline reductions in choroidal and retinal perfusion in non-exudative disease, often extending beyond atrophic regions. Anti-VEGF injections produced acute reductions in MBR, particularly with brolucizumab, with partial recovery over time; drug-specific differences suggest a potential impact on geographic atrophy progression. In DR, LSFG revealed early microvascular dysfunction even in asymptomatic eyes. Retinal and choroidal MBR and blowout score correlated with HbA1c, DR severity, and inflammatory mediators. Intravitreal anti-VEGF therapy consistently reduced retinal and choroidal MBR and RFV, while conventional panretinal photocoagulation decreased choroidal flow and vascular caliber more robustly than patterned laser, reflecting oxygenation-driven VEGF modulation. Low baseline MBR predicted higher central macular thickness and reduced therapeutic response in diabetic macular edema. Conclusions: LSFG provides reproducible, rapid, and non-invasive quantitative insights into ocular hemodynamics across degenerative retinal diseases. Its integration into multimodal imaging may facilitate early diagnosis, support personalized management, and assist in the prognostic assessment of retinal and choroidal vascular disorders.