Association of Optical Coherence Tomography Angiography Biomarkers with Fluorescein Angiography Retinal Inflammation Scores in Behcet’s Retinal Vasculitis

To investigate the association of macular vessel density (VD) and foveal avascular zone (FAZ) parameters with the severity of retinal inflammation in patients with Behcet's retinal vasculitis. In this prospective study, consecutive patients with Behcet's uveitis who had fluorescein angiography (FA)-proven retinal vasculitis underwent concurrent OCTA and FA imaging. Severity of retinal inflammation was quantitatively evaluated using our previously devised FA scoring system. Fovea-centered 6 × 6 mm spectral-domain OCTA scans were acquired, and VD of superficial vascular complex (SVC), deep vascular complex (DVC) and retina were measured for different measurement zones based on the ETDRS grid. FAZ area and perimeter were also measured. In total 54 eyes with mean age of 34.94 (±11.85) years were included. Mean best corrected visual acuity (BCVA) was 0.18 (±0.23) LogMAR. Mean FA score was 9.54 (±9.56). FAZ area and perimeter were not significantly associated with FA scores (p > 0.05). There was a significant negative association between superficial, deep and retina VD in all measurement zones except the fovea, with FA scores. This negative association was stronger in the DVC. Accordingly, greater deep VD in parafovea (B = -0.93; 95% CI -1.34 to -0.53), perifovea (B = -0.70; 95% CI -1.06 to -0.34) and whole ETDRS grid (B = -0.80; 95% CI -1.18 to -0.41) were associated with lower FA retinal inflammation scores. Greater macular vessel density is associated with lower retinal inflammation in patients with Behcet's retinal vasculitis in non-ischemic stages. The deep vascular complex is more severely affected in these patients. OCTA biomarkers have shown promising results for detecting microvascular changes in retinal inflammation.