Macular edema after retinal vein occlusions. Macular morphometry and chorioretinal hemodynamics

This review article summarizes current data on the pathogenesis of macular edema after retinal vein occlusions (RVOs) and patterns of macular morphometry and chorioretinal hemodynamics. RVOs account for 60% of acute vascular eye diseases. The major cause of vision loss in RVOs is macular edema which results from subclinical inflammation characterized by leukostasis and enhanced expression of adhesion molecules and production of cytokines increasing retinal capillary permeability. The association between the severity of macular edema and vitreous levels of pro-inflammatory mediators (IL-1β, IL-6, TNF-α, MCP-1, and VEGF) is established. Cystic lesions and detachment of the neuroepithelium (75%) are typical for macular edema after RVOs. Impaired chorioretinal hemodynamics (as demonstrated by a significant reduction of vascular density in the superficial and deep vascular plexus, significant decrease in peak diastolic flow velocity, and increase in resistivity index in the ophthalmic artery and short posterior ciliary arteries) is also reported. The paper addresses etiological factors of RVOs and pathogenesis of macular edema, technical tools for vital assessment of the retina, and choroidal/retinal hemodynamics. This provides great opportunities for a complex in-depth study of the development and course of macular edema to identify potential predictors of its development and persistence. Keywords: retinal vein occlusions, macular edema, morphometry, chorioretinal hemodynamics. For citation: Fil' A.A., Sorokin E.L., Kolenko O.V. Macular edema after retinal vein occlusions. Macular morphometry and chorioretinal hemodynamics. Russian Journal of Clinical Ophthalmology. 2021;21(3):164–168 (in Russ.). DOI: 10.32364/2311-7729-2021-21-3- 164-168.