Abstract
Purpose :
To identify microvascular changes in Systemic Lupus Erythematosus (SLE) patients using perifoveal vascular perfusion densities derived from Optical Coherence Tomography Angiography (OCTA) and to compare current staging of SLE severity based on clinical features with perifoveal perfusion.
Methods :
A total of 2769 3mm×3mm OCTA scans imaged with a spectral-domain OCT system (Optovue XR Avanti, Fremont, CA) from 951 patients were reviewed and 5 subjects with SLE (9 eyes) and 5 age-matched controls (10 eyes) met inclusion criteria for analysis. En face OCTA images of the SCP, DCP, and foveal avascular zone (FAZ) were obtained for each eye and quantitative values of Vessel Density (VD) were extracted for comparison to Katz Clinical Severity scores using ANOVA and linear regression analysis.
Results :
The average VD ± SD for normal subjects in the 3 x 3-mm scans were 26.11 ± 1.2 and 37.45 ± 1.8 for the superficial and deep capillary plexus respectively. For SLE subjects the means ± SD were 18.46 ± 0.84 and 30.22 ± 1.5 for superficial and deep respectively. The mean FAZ was found to be 0.207 mm ± 0.02 for healthy controls and 0.350 mm ± 0.02 for SLE subjects. Hence, both the superficial and deep capillary plexuses had a statistically significant reduction in vessel density in the SLE group when compared to the control group (p < 0.05), and the FAZ was 1.7 times as large in SLE eyes (p < 0.001). SLE severity approached significant correlation with SCP VD (p = 0.07), DCP VD (p = 0.08), and FAZ size (p = 0.18), and hydroxychloroquine dose does not confound or contribute to the associations between lupus severity and SCP, DCP, nor FAZ.
Conclusions :
OCT-Angiography's ability to detect subclinical findings may offer a non-invasive, sensitive adjunct to characterize and detect systemic SLE. After an extensive literature review, to our knowledge, we are the first to demonstrate an enlarged FAZ in patients with lupus and the first to study VD in this disease. It is notable that the SCP VD demonstrated a dose-response type negative relationship with increased lupus severity, as did the DCP VD and FAZ area for mild and moderate severities. It appears that subclinical SLE pathology can now be detected with OCTA, and OCTA may further prove to provide a means for monitoring the severity or progression of other microvascular diseases.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.