Analysis of Vascular Changes of Fundus in Behcet's Uveitis by Widefield Swept-source Optical Coherence Tomography Angiography and Fundus Fluorescein Angiography.

Abstract

To investigate vascular changes of fundus in quiescent Behçet's uveitis(BU) based on widefield swept-source optical coherence tomography angiography(SS-OCTA) and fluorescein angiography (FA). This case-control study included 33 quiescent BU patients(57eyes)and 35 healthy people(60 eyes) as the control. All participants underwent the widefield SS-OCTA, and BU patients additionally underwent the FA. The quantitative analysis of the widefield SS-OCTA assessed the vessel density(VD) of 9 anatomic locations in the fundus. Vascular leakage and retinal nonperfusion on FA were assessed in BU patients. Compared with the control group using Mann-Whitney U test, BU patients had enlargement of foveal avascular zone (FAZ) (P=0.005, P=0.04, respectively) and decreased VD within a 300μm width around the FAZ(FAZ300μm) (P=0.001, P<0.0001, respectively) both in the superficial and deep retina. Larger FAZ size and lower FAZ300μm were correlated with higher logarithm of the minimum angle of resolution best-corrected visual acuity in BU (P≤0.003, P<0.0001, respectively). VD of choriocapillaris(CC), as the most widely involved of all layers of the retina and choroid, was lower in 6 locations(P≤ 0.03∼0.0001) in the peripheral fundus of BU compared to the controls. Vascular leakage and retinal nonperfusion in the peripheral fundus was observed in 54.4% and 66.7% of the patients on FA. Fovea and peripheral fundus were prone to the damage of ischemia as evidenced by significantly decreased VD of capillaries. Combination of SS-OCTA with FA could accurately evaluate the changes in the retinal and choroidal vasculature in BU.