ASSESSMENT OF PARAFOVEAL RETINAL VASCULATURE IN BEHÇET'S SYNDROME USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

Abstract

Purpose : OCT-Angiography (OCT-A) has a unique ability to analyze retinal vascular plexuses, providing additional information about ocular involvement in Behçet's syndrome (BS), which manifests mainly as an occlusive retinal vasculitis. We performed a cross-sectional quantitative and qualitative assessment of parafoveal retinal vascular plexuses in Behçet's uveitis (BU) patients, comparing them with non-ocular Behçet's syndrome (NOBS) patients and healthy subjects (HS).

Methods : Twenty-six patients that met the International Criteria for Behçet's Disease (2014), 16 with BU (age 43.4±12.8 years) and 10 with NOBS (40.7±9 years), and 10 sex-matched HS (42.2±11.7 years) were evaluated with Spectralis® OCT-A (Heidelberg Engineering, Heidelberg, Germany) (Figure 1). Five eyes with poor fixation or media opacities were excluded. Foveal avascular zone (FAZ) area and circularity index (CI) were manually measured in superficial vascular plexus (SVP), intermediate capillary plexus (ICP), and deep capillary plexus (DCP), using ImageJ (NIH, Bethesda, Maryland, USA). Parafoveal vessel density (VD) was quantified for superior, nasal, inferior, and temporal quadrants. Perifoveolar arcade disruption frequency was also evaluated. All biomarkers were correlated with age of onset, duration of disease, and episodes in BU patients. Statistical analysis was performed using generalized estimating equations with a normal distribution.

Results : Variance analysis showed a statistically significant difference (p < 0.05) in global VD between BU and NOBS groups and between BU and HS groups in ICP (nasal and inferior quadrants) and DCP (all quadrants) (Figure 2). No differences for CI, temporal VD in SVP and ICP, and perifoveolar arcade disruption were found among the groups (p > 0.05). FAZ area and other VD parameters were significantly different only between BU and HS. In the BU group, the Pearson correlation coefficient showed the age of onset has an inverse correlation with the FAZ area (r = -0.460) and a positive correlation with VD in SVP (r = 0.447).

Conclusions : In patients with BU, the deeper the retinal vascular layer, the lower is the VD. Nasal and inferior quadrants are the most affected, while the temporal quadrant is relatively spared. The age of onset seems to be a predictor for parafoveal vascular changes in BS. None biomarker showed a statistically significant difference between NOBS patients and HS.

This is a 2021 ARVO Annual Meeting abstract.