Adaptive vessel tracing and segmentation in OCT enables robust detection of wall-to-lumen ratio abnormalities in 5xFAD mice

The wall-to-lumen ratio (WLR) of retinal blood vessels promises a sensitive marker for physiological assessment of eye conditions. However, in vivo measurement of vessel wall thickness and lumen diameter is still technically challenging, hindering wide application of WLR in research and clinical settings. In this study, we demonstrate the feasibility of using optical coherence tomography (OCT) as one practical method for in vivo quantification of WLR in the retina. Based on three-dimensional vessel tracing, lateral en face and axial B-scan profiles of individual vessels were constructed. By adaptive depth segmentation for en face vessel OCT projection, the vessel wall thickness and lumen diameter are reliably quantified. A comparative study of control and 5xFAD mice confirmed WLR as a sensitive marker of the eye condition.