Depth perception on fundus images using a single-channel stereomicroscopy

Edalat Radfar,Hyunseon Yu,Byungjo Jung,Tien Son Ho,Seung Ho Choi

doi:10.1142/s1793545821500127

Abstract

Typical fundus photography produces a two-dimensional image. This makes it difficult to observe the microvascular and neural abnormalities, because the depth of the image is missing. To provide depth appreciation, we develop a single-channel stereoscopic fundus video imaging system based on a rotating refractor. With respect to the pupil center, the rotating refractor laterally displaces the optical path and the illumination. This allows standard monocular fundus cameras to generate stereo-parallax and image disparity through sequential image acquisition. We optimize our imaging system, characterize the stereo-base, and image an eyeball model and a rabbit eye. When virtual realities are considered, our imaging system can be a simple yet efficient technique to provide depth perception in a virtual space that allows users to perceive abnormalities in the eye fundus.

Highlights

Binocular human vision a distance of 50–75 mm provides three-dimensional (3D) depth perception in object observation
In two-dimensional (2D) imaging, both eyes see the same images that are captured by a camera, the brain can still achieve a level of depth perception due to pattern recognition such as shadows and size.[2]
We provide a rapid sequential automatic image acquisition that can be developed with a standard monocular fundus camera, namely the single-channel stereoscopic fundus video imaging modality based on rotating refractor

Summary

Introduction

Binocular human vision a distance of 50–75 mm provides three-dimensional (3D) depth perception in object observation. The topography of the blood vessels around the optic nerve head is one of the most important diagnostic parameters, in glaucoma diagnosis.[4] In this case, the imaging target is not accessible, and 2D imaging may not be fully informative. Optical approaches such as stereoscopic imaging, confocal scanning laser tomography, and optical coherence tomography (OCT) can be used to obtain useful geometric and structural data.[4] Stereoscopic images of the fundus can be used to assess those blood vessels in glaucoma or other medical diagnostic procedures using popular fundus camera approaches owing to the wide availability of fundus cameras.[4]

Methods

Results

Conclusion