Photo Credit: miodrag ignjatovic

The following is a summary of “Expanded Field OCT Angiography Biomarkers for Predicting Clinically Significant Outcomes in Non-Proliferative Diabetic Retinopathy,” published in the October 2024 issue of Ophthalmology by Ding et al. 

Researchers conducted a retrospective study to evaluate the utility of extended field swept-source Optical Coherence Tomography Angiography (SS-OCTA) imaging biomarkers in predicting clinically significant outcomes in eyes with Non-Proliferative Diabetic Retinopathy (NPDR).  

They examined 88 eyes from 57 participants (median age: 64.0 years; mean duration of diabetes: 15.8 years), all with at least 2 consecutive SS-OCTA scans over a minimum follow-up period of 6 months. The evaluation focused on the presence of intraretinal microvascular abnormalities (IRMAs) at baseline and the stability during the follow-up period using 12 × 12-mm angiograms. FIJI and the ARI Network calculated the baseline nonperfusion ischemia index (ISI) and other SS-OCTA metrics. Significant clinical outcomes were defined as the occurrence of occurrence of 1 or more of the following at the last available clinical visit: significant diabetic retinopathy (DR) progression (2-step DR progression or progression to proliferative diabetic retinopathy [PDR]); development of new center-involving diabetic macular edema (CI-DME); and initiation of treatment with pan-retinal photocoagulation (PRP) or anti-vascular endothelial growth factor (anti-VEGF) injections during the follow-up. Mixed-effects Cox regression models were employed outcomes.  

The results showed that after a clinical follow-up period of 25.1 ± 10.8 months, significant clinical outcomes occurred in 17 eyes (19.3%). Among these, 7 eyes (8.0%) experienced substantial progression, and 4 eyes (4.5%) developed CI-DME, Anti-VEGF injections were initiated in 15 eyes (17.0%), while PRP was started in 2 eyes (2.3%). Adjusting for age, duration of DM, and prior Anti-VEGF treatments revealed that non-stable IRMAs during the follow-up period and a higher ischemia index at baseline were significantly associated with the occurrence of significant clinical outcomes, with HRs of 3.88 (95% CI: 1.56-9.64; P =0.004) and 1.05 (95% CI: 1.02-1.09; P =0.004), respectively.  

Investigators concluded that eyes with non-stable IRMAs over time and greater ischemia at baseline faced a higher risk of significant clinical outcomes, indicating that expanded field SS-OCTA could provide enhanced prognostic benefits for clinical DR staging and high-risk patient prediction. 

Source: ajo.com/article/S0002-9394(24)00485-9/abstract