Sensitive optical coherence tomography angiography parameters detecting retinal vascular changes in Behcet's uveitis.

Purpose: To compare the retinal parameters in Behcet's uveitis (BU) patients with wide-field swept-source optical coherence tomography angiography (SS-OCTA) and find a sensitive OCTA parameter.

Methods: Fifty-two eyes from 52 quiescent BU patients and 50 healthy eyes were included. All subjects underwent SS-OCTA examinations with 12 × 12 mm region. Vessel density (VD) and flow area (FA) in nerve fiber layer (NFL), superficial vascular plexus (SVP), intermediate capillary plexus (ICP) and deep capillary plexus (DCP) were analyzed and compared in central, parafoveal, and peripheral regions with diameters of 1, 6 and 12 mm. Receiver operating characteristic curves (ROC), area under the curve (AUC), correlation analysis between OCTA metrics and best-corrected visual acuity (BCVA) were respectively evaluated.

Results: BU patients showed significantly lower peripheral VD and FA in NFL (P = 0.019 and 0.002), lower central and parafoveal VD-SVP (P = 0.006 and <0.001), and lower VD-ICP, VD-DCP, FA-SVP, FA-ICP and FA-DCP in all regions (all P < 0.05) as compared to healthy controls. The ROC analysis indicated that the parafoveal, peripheral FA-DCP, and a combination of the two metrics were sensitive parameters for identifying retinal vessel changes in BU (AUC=0.90, 0.90, 0.91, respectively). The parafoveal and peripheral FA-DCP were negatively associated with logMAR BCVA (r=-0.764, P < 0.0001; r=-0.641, P < 0.0001).

Conclusion: The deep retinal layers were apt to be affected in BU patients. The parafoveal and peripheral FA values of DCP may be sensitive parameters for detecting retinal vasculature alterations in BU.