Vitreoretinal Interface Cells Correlate in Vivo with Uveitis Activity and Decrease with Anti-Inflammatory Treatment.

Purpose: To highlight the utility of en face swept -source optical coherence tomography angiography (SS-OCTA) in assessing vitreoretinal interface cells (VRICs) of patients with active uveitis and their dynamics. Methods: In this prospective, single -center study , 20 eyes from patients with active uveitis were analyzed using six 6 x 6 -mm macular scans at three time points: active inflammation (baseline), clinically improving (T1), and resolved inflammation (T2). VRICs were visualized using 3-mu m en face OCT slabs on the inner limiting membrane. The variation of VRIC number, density, and size over time was assessed, and VRIC measurements were compared with clinical grading. Results: At baseline, the VRIC count was significantly higher (552.5 VRICs) than that of the healthy controls (478.2 VRICs), with a density of 15.3 cells/mm 2 . VRIC number decreased significantly to 394.8 ( P = 0.007) at T1, with a density of 10.9 cells/mm 2 ( P = 0.007). VRIC size reduced from 6.8 mu m to 6.3 mu m at T1 ( P = 0.009) and remained stable at T2 ( P = 0.3). Correlation coefficients between inflammatory parameters (anterior chamber cells and National Eye Institute vitreous haze), and VRIC count indicated a positive correlation at baseline ( r = 0.53), weakening at T1 ( r = 0.36), and becoming negative at T2 ( r = - 0.24). Conclusions: En face SS-OCTA revealed increased VRIC number and size in active uveitis, likely due to monocyte recruitment. Post -inflammation control, VRIC number, size, and density significantly decreased, returning to normal despite residual anterior chamber cells or vitreous haze. Translational Relevance: Visualization of VRICs by in vivo OCT opens up new opportunities for therapeutic targets.