In Ophthalmology. Retina
OBJECTIVE : The purpose is to evaluate the longitudinal change of quantitative ultra-widefield angiographic (UWFA) parameters and correlate them with functional outcomes and Spectral Domain Optical Coherence Tomography (SD-OCT) metrics.
DESIGN : This study is a post-hoc analysis of the Phase II RUBY study: a prospective, randomized trial of Diabetic Macular Edema (DME) patients treated with either intravitreal aflibercept (IAI) or combined IAI/nesvacumab (anti-angiopoietin 2 mAb).
SUBJECTS : Subjects with DME that underwent UWFA across all treatment groups (n=44).
METHODS : A machine learning-enabled feature extraction system generated panretinal quantitative UWFA metrics, including leakage, ischemia, and microaneurysm (MA) burden. Zonal assessments were performed corresponding to the macula, mid-periphery, and far periphery.
MAIN OUTCOME MEASURES : Changes in ischemic area and index (proportion of nonperfusion in analyzable retina), leakage area and index (proportion of leakage in analyzable retina), and MA count at baseline, week 12, week 24, week 36 were analyzed. SD-OCT quantitative metrics such as central subfield thickness (CST), Ellipsoid Zone (EZ) integrity parameters, intraretinal fluid (IRF) volume, and subretinal fluid (SRF) volume were extracted via a machine-learning enhanced OCT feature extraction platform and analyzed. Additionally, the effect of these changes on best correct visual acuity (BCVA) was evaluated.
RESULTS : Mean panretinal leakage index, zonal leakage area, and panretinal MA count improved significantly between baseline and week 36. Panretinal ischemic index decreased between baseline and week 36, with some aspects showing significant improvement. Mean BCVA significantly improved from baseline to week 36. There was a significant inverse correlation between change in BCVA and change in macular leakage area. A direct correlation was observed between both baseline macular leakage area and panretinal leakage index with IRF volume, SRF volume, and EZ disruption on OCT.
CONCLUSION : Assessment of UWFA parameters demonstrates a significant improvement in panretinal leakage index, leakage area, and MA burden in eyes treated with IAI with or without nesvacumab. A numerical reduction in panretinal ischemic index and area was also noted. The analysis also shows the critical association of leakage with visual and OCT features. This highlights the potential role of UWFA in disease burden assessment, with leakage parameters serving as a primary endpoint.
Sarici Kubra, Yordi Sari, Martin Alison, Lunasco Leina, Mugnaini Christopher, Chu Karen, Moini Hadi, Vitti Robert, Srivastava Sunil K, Ehlers Justis P
2023-Feb-01
