Related Experiment Video
Updated: Jan 23, 2026

Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy oSLO and Optical Coherence Tomography OCT
Published on: August 4, 2018
ReLayer: a Free, Online Tool for Extracting Retinal Thickness From Cross-Platform OCT Images
Giovanni Ometto1, Ismail Moghul2, Giovanni Montesano1,3,4
1Division of Optometry and Visual Science, School of Health Sciences, City, University of London, London, UK.
Purpose:
To describe and evaluate a free, online tool for automatically segmenting optical coherence tomography (OCT) images from different devices and computing summary measures such as retinal thickness.
Methods:
ReLayer (https://relayer.online) is an online platform to which OCT scan images can be uploaded and analyzed. Results can be downloaded as plaintext (.csv) files. The segmentation method includes a novel, one-dimensional active contour model, designed to locate the inner limiting membrane, inner/outer segment, and retinal pigment epithelium. The method, designed for B-scans from Heidelberg Engineering Spectralis, was adapted for Topcon 3D OCT-2000 and OptoVue AngioVue. The method was applied to scans from healthy and pathological eyes, and was validated against segmentation by the manufacturers, the IOWA Reference Algorithms, and manual segmentation.
Results:
Segmentation of a B-scan took ≤1 second. In healthy eyes, mean difference in retinal thickness from ReLayer and the reference standard was below the resolution of the Spectralis and 3D OCT-2000, and slightly above the resolution of the AngioVue. In pathological eyes, ReLayer performed similarly to IOWA (P = 0.97) and better than Spectralis (P < 0.001).
Conclusions:
A free online platform (ReLayer) is capable of segmenting OCT scans with similar speed, accuracy, and reliability as the other tested algorithms, but offers greater accessibility. ReLayer could represent a valuable tool for researchers requiring the full segmentation, often not made available by commercial software.
Translational Relevance:
A free online platform (ReLayer) provides free, accessible segmentation of OCT images: data often not available via existing commercial software.
Related Concept Videos
Directional Relays
Overcurrent Relays
Instantaneous overcurrent relays activate immediately when the input current exceeds a predetermined value, known as the pickup current, instantly energizing the circuit breaker trip coil. This rapid response is vital for addressing severe faults quickly.
Time-delay overcurrent relays, on the other...
Differential Relays
Line Protection with Impedance Relays
Under normal conditions, low load currents keep the measured...
Pilot and Numeric Relaying
Diencephalon: Thalamus and Information Relay

