Widefield OCT Angiography Biomarkers for Predicting Clinically Significant Outcomes in Eyes with Nonproliferative Diabetic Retinopathy

Abstract

Purpose : To assess the utility of widefield swept-source optical coherence tomography angiography (WF SS-OCTA) imaging biomarkers in predicting the occurrence of clinically significant outcomes in eyes with nonproliferative diabetic retinopathy (NPDR).

Methods : Prospective longitudinal study. Participants with mild to severe NPDR with at least two WF SS-OCTA scans in consecutive visits over a follow-up period of at least 6 months were included. The presence of intraretinal microvascular abnormalities (IRMAs) at baseline and the stability of IRMAs during follow-up period on 12x12-mm angiography were evaluated. Stable IRMAs were defined as all IRMA lesions within the field of view that maintained their original structure, along with the surrounding non-perfused tissue. Baseline nonperfusion ischemia index (ISI) and other OCTA metrics were calculated on FIJI and ARI Network. Significant clinical outcomes were defined as one or more of the following: 1) 2-step or more DR progression (according to international clinical DR severity scale); 2) new development of center-involving diabetic macular edema; and 3) initiation of treatment with pan-retinal photocoagulation (PRP) or anti-VEGF injections during follow-up period. Cox mixed-effects regression models was used to explore the predictors for significant clinical outcomes.

Results : We included 88 eyes from 57 participants (age: 59.3±12.4). Over 28.6±10.5 months, 19.1% (17/88) eyes developed significant clinical outcomes. Univariate Cox mixed-effects regression analysis revealed that a higher baseline ISI and non-stable IRMAs during follow-up period were associated with the occurrence of significant clinical outcomes. In multivariable Cox mixed-effects regression models, a higher baseline ISI (hazard ratio: 1.10, p<0.001) and the lack of stability in IRMAs (hazard ratio: 0.19, p=0.002) remained significantly associated after adjusting for age, diabetes duration, and prior anti-VEGF injections at baseline.

Conclusions : In conclusion, NPDR eyes with worse retinal perfusion at baseline and non-stable IRMAs over time are in higher risk of developing significant clinical outcomes in the short term. Our findings suggest that WF-OCTA may offer additional prognostic benefits for clinical DR staging and predicting high-risk patients.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Figure 1. 12x12-mm OCTA angiography demonstrating stable IRMAs from baseline to follow-up.