Evolutionary mosaicking for high-resolution wide-field optical coherence tomography angiography

Abstract

[Abstract]: Optical coherence tomography angiography (OCTA) is a noninvasive imaging modality that produces retinal blood flow images. However, the limited field of view (FOV) of typical high-resolution scan poses challenges for comprehensive analysis. This work presents a fully automatic method for generating high-resolution wide-field OCTA mosaics from overlapping scans, addressing the need for wider FOVs without requiring advanced OCTA equipment or manual mosaicking. The proposed approach consists of a three-stage pipeline: an initial mosaic is constructed using correlation-based template matching, refined with an evolutionary algorithm to optimize vascular continuity at seams, and finalized with a blending stage to improve overall quality. Unlike existing methods, our approach avoids keypoint extraction or input image preprocessing, making it robust against noise and artifacts typically present in clinical OCTA images. Using a correlation-based metric that measures the degree of vascular continuity at the seams in each mosaic, we obtained a mean and standard deviation equal to (before blending) for all the mosaics analyzed. The proposed method presented robust results, producing high-resolution wide-field OCTA mosaics.