Prediction of Visual Acuity Response to Ranibizumab in Age-Related Macular Degeneration Using Artificial Intelligence-Based Analysis of Fluorescein Angiography

Abstract

Purpose : Quantification of vascular parameters from intravenous fluorescein angiography may provide insight into treatment prognosis in neovascular age-related macular degeneration (nAMD). We hypothesize that baseline blood-retinal-barrier (BRB) permeability can predict improvement in best-corrected visual acuity (BCVA) in response to ranibizumab in patients with nAMD.

Methods : A prospective cohort study was conducted at a single center in Toronto, Canada involving patients over 50 years with nAMD. At baseline, patients were imaged with fluorescein angiography using an ultra-widefield scanning laser ophthalmoscope. Images were processed using the artificial intelligence RETICAD system to extract quantitative retinal vascular parameters, including BRB permeability, perfusion, and blood flow. All nAMD patients were treated using a pro re nata regimen of ranibizumab and final outcomes were measured at 12 months of follow up. Associations between quantitative vascular parameters with functional and anatomical outcomes were examined using univariable and multivariable regression models. Receiver-operating characteristic (ROC) curves and area-under-the-curve (AUC) values were used to determine the predictive value of fluorescein angiography parameters for improvement in BCVA following treatment.

Results : The study population included 60 eyes from 60 patients with confirmed nAMD, and seven eyes from seven heathy controls. Among patients with nAMD, most were female (n=37, 61.7%), Caucasian (n=44, 73.3%), and had a mean age of 80.8 ± 8.0 years. On multivariable analysis, baseline central BRB permeability was associated with the change in BCVA from baseline to 12 months (p=0.034) and the number of injections over 12 months (p=0.003). Patients with improved BCVA had significantly lower baseline values of central (p=0.003) and peripheral (p=0.007) BRB permeability compared to those with no improvement. ROC analysis revealed baseline BRB permeability was a strong predictor of BCVA improvement (AUC=0.85).

Conclusions : Baseline quantitative fluorescein angiography parameters, particularly BRB permeability, were predictive of improvement in BCVA following ranibizumab treatment. Future work should explore associations between quantitative fluorescein angiography parameters and functional and anatomical outcomes in diverse nAMD patient populations.

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