In vivo visualization of macrophage-like cells in patients with uveitis by use of en face swept source optical coherence tomography

Aims: To detect macrophage-like cells (MLCs) in uveitis patients and describe their characteristics compared to healthy subjects by using en face SS-OCTA. Methods: Fifteen consecutive patients with “active” uveitis and 11 healthy participants underwent 6 macular scans of 6×6mm using SS-OCTA. The 3μm en face OCT slabs on inner limiting membrane were used to visualize the MLCs. Results: In healthy subjects there was an average of 478.2±149.7 MLCs with a density of 13.28±4.16 cells/mm2. MLCs were larger in patients with “active” uveitis than in controls (891.18±69.46 µm2 vs.885±77.53 µm2). Patients with “active” anterior uveitis had a significantly reduced count and density of MLCs (172±14.68 and 4.77±0.4 cell/mm2) compared to controls, while patients with posterior uveitis had a statistically increased count (546.1±132.4) and area (909.23+/-54.97 µm2) of MLCs compared to controls. Conclusions: MLCs detected with en face SS-OCTA are increased in number and size in active posterior uveitis eyes compared to controls.