EMLCs are increased in RVO and show a spatially heterogeneous distribution pattern, with eMLC count associated with disease duration, prior anti-VEGF exposure, and ischemic status, suggesting ultra-widefield OCTA-based eMLC quantification may provide a clinically accessible imaging biomarker for inflammatory involvement in RVO.
RVO eyes showed significantly higher eMLC density compared to unaffected fellow eyes.
RVO eyes demonstrated greater central subfield thickness (CST) and larger foveal avascular zone (FAZ) area compared to fellow eyes.
Within RVO eyes, eMLC density showed a spatially heterogeneous distribution, with lower density in the macular region than in the peripheral retina.
eMLC density was lower within nonperfusion areas (NPAs) compared to the remaining retinal regions within the same eye.
In RVO eyes, eMLC count was independently associated with disease duration, prior anti-VEGF injection number, and ischemic status.
A machine-learning-based pipeline was used to quantify eMLC density and morphology from ultra-widefield swept-source OCTA images.
Ultra-widefield OCTA-based eMLC quantification was proposed as a potentially clinically accessible imaging biomarker for inflammatory involvement in RVO.
This research suggests that a type of immune cell called epiretinal macrophage-like cells (eMLCs) — cells that sit on the surface of the retina and are thought to be involved in inflammation — are more numerous in eyes affected by retinal vein occlusion (RVO), a condition where a vein in the retina becomes blocked, than in the unaffected fellow eyes of the same patients. Using a wide-field eye imaging technology called swept-source optical coherence tomography angiography (OCTA) and a machine-learning tool to count and measure these cells, the researchers found that RVO eyes had about 65% higher eMLC density and nearly double the total eMLC area compared to healthy fellow eyes. RVO eyes also showed thicker retinas at the center and larger areas of poor blood vessel structure (the foveal avascular zone), indicating more disease-related damage. The study also found that these immune cells are not spread evenly across the retina. In RVO-affected eyes, eMLC density was actually lower in the central macular region and, importantly, lower within areas of poor blood flow (nonperfusion areas) compared to other parts of the same retina. The total number of eMLCs in an RVO eye was linked to how long the patient had had the disease, how many anti-VEGF injections (a common treatment) they had previously received, and whether the eye had significant areas of poor blood supply. This research suggests that measuring eMLCs using wide-field retinal imaging could serve as a non-invasive way to track inflammation in RVO, potentially helping clinicians better understand disease progression and treatment response. The authors note, however, that some findings — particularly those comparing patients at different stages of disease — are preliminary and need to be confirmed in larger, prospective studies before drawing firm clinical conclusions.
Lin H, Liu Y, Wu Z, Wang Y, Zhou L, Xu Y, et al.. (2026). Ultra-Widefield OCTA Mapping of Epiretinal Macrophage-Like Cells in Patients With Retinal Vein Occlusion.. Translational vision science & technology. https://doi.org/10.1167/tvst.15.9.9