Abstract
Purpose :
Quantitative ultra-widefield angiography (UWFA) provides unique insights into disease burden in retinal vascular disease. The correlation between quantitative UWFA features and Diabetic Retinopathy Severity Scale (DRSS) alterations during anti-VEGF therapy remains unknown. The purpose of this study was to evaluate whether select retinal vascular features on UWFA are associated with improvement in the DRSS in eyes with diabetic macular edema (DME) treated with intravitreal aflibercept injection (IAI) in the PERMEATE study.
Methods :
PERMEATE is an IRB-approved, prospective open-label 12-month study for treatment-naïve eyes with macular edema secondary to retinal vascular disease, including DME. Subjects received 2mg IAI q4 weeks for the first 6 months, followed by 2 mg q8 weeks. UWFA images (California, Optos) were analyzed utilizing a novel quantitative assessment platform to quantify microaneurysm (MA) counts and leakage index. Grading of DR for DRSS was performed using Optos ultra-widefield imaging. Eyes with underlying diabetic retinopathy were selected for this analysis. Statistical analysis was performed using student t-test and Pearson’s correlation.
Results :
Fourteen subjects had images that were sufficient quality for analysis. At baseline, forty three percent of patients (n=6) had a baseline DRSS score of 43, 50% (n=7) had a score of 53, and 7% (n=1) presented 71 as DRSS score. At month 12, 50% of subjects (n=7) had ≧ 2 steps DRSS score improvement from baseline. IAI resulted in a 78.1% decrease in panretinal leakage index (p=0.02) at month 12. At month 12, IAI treatment resulted in a non-significant decrease in total MA count (-32.1%, p=0.09) and a significant reduction in posterior pole MA (-42.3%, p=0.01). Reduction in DRSS was not associated with change in leakage index. DRSS improvement demonstrated a trend towards significant direct correlation with total MA reduction (r = -0.48; p=0.07) and significantly directly correlated with peripheral MA reduction (r = -0.65; p=0.01).
Conclusions :
Therapy with IAI demonstrated DRSS improvement in a large proportion of patients with DME. Reduction in peripheral MA count on quantitative UWFA correlated with DRSS improvement. Additional research is ongoing to explore potential imaging biomarkers for therapeutic response and confirming these findings in a larger study cohort.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.