Innovative Macula Capillaries Plexuses Visualization with OCTA B-Scan Graph Representation: Transforming OCTA B-Scan into OCTA Graph Representation

Abstract

Purpose: The aim of this study is to transform optical coherence tomography angiography (OCTA) scans into innovative OCTA graphs, serving as novel biomarkers representing the macular vasculature. Patients and Methods: The study included 90 healthy subjects and 39 subjects with various abnormalities (29 with diabetic retinopathy, 5 with age-related macular degeneration, and 5 with choroid neovascularization). OCTA 5µm macular coronal views (MCVs) were generated for each subject, followed by blood vessel segmentation and skeleton processing. Subsequently, the blood vessel density index, blood vessel skeleton index, and blood vessel tortuosity index were computed. The graphs of each metric were plotted against the axial axes of the OCTA B-scan, representing the integrity of vasculature at successive 5µm macular depths. Results: The results revealed two significant findings. First, the B-scans from OCTA can be transformed into OCTA graphs, yielding three specific OCTA graphs in this study. These graphs provide new biomarkers for assessing the integrity of deep vascular complex (DVC) and superficial vascular complex (SVC) within the macula. Second, a statistically significant difference was observed between normal (n=90) and abnormal (n=39) subjects, with a t-test p-value significantly lower than 0.001. The Mann–Whitney u-test also yielded significant difference but only between the 90 normal and 29 DR subjects. Conclusion: The novel OCTA graphs offer a unique representation of the macula’s SVC and DVC, suggesting their potential in aiding physicians in the diagnosis of eye health within OCTA clinics. Further research is warranted to finalize the shape of these newly derived OCTA graphs and establish their clinical relevance and utility. Plain Language Summary: The current state of optical coherence tomography angiography (OCTA) machines lacks the provision of OCTA graphs depicting macula vasculature. This article presents a new technique that transforms OCTA B-Scan data into OCTA plots, representing the vasculature through graphs or curves. The results showed that: ● The method is an innovative and successful endeavor to transform the OCTA scan data into a graphical representation, introducing an innovative representation of the macula capillaries’ plexuses’ diffusion. ● The method successfully characterized and distinguished the superficial from the deep capillaries plexuses in the macula. ● The physicians observed that the new method can be of futuristic advantage to OCTA clinics in monitoring patient’s health and probably differentiating the normal from abnormal OCTA patients, but this needs dedicated clinical research.