Application of a wide-field phantom eye for optical coherence tomography and reflectance imaging

Abstract

Optical coherence tomography (OCT) and reflectance imaging are used in clinical practice to measure the thickness and transverse dimensions of retinal features. The recent trend towards increasing the field of view (FOV) of these devices has led to an increasing significance of the optical aberrations of both the human eye and the device. We report the design, manufacture and application of the first phantom eye that reproduces the off-axis optical characteristics of the human eye, and allows the performance assessment of wide-field ophthalmic devices. We base our design and manufacture on the wide-field schematic eye, [Navarro, R. J. Opt. Soc. Am. A, 1985, 2.] as an accurate proxy to the human eye and enable assessment of ophthalmic imaging performance for a external FOV. We used multi-material 3D-printed retinal targets to assess imaging performance of the following ophthalmic instruments: the Optos 200Tx, Heidelberg Spectralis, Zeiss FF4 fundus camera and Optos OCT SLO and use the phantom to provide an insight into some of the challenges of wide-field OCT.

Spectroscopic oximetry in the eye: a review

“…[85] Bio-mimicking phantoms may be advantageous in future because they could simulate realistic blood flow patterns and thus reproduce features like laminar flow seen in branching retinal veins. [42] Corcoran et al, (2014) [87] created an advanced, wide-field spherical eye with 3D-printed phantom retina, an optics based on a rigorous schematic eye model. The retina incorporated embedded image resolution test targets and simulated retinal tissue layers.…”

“…This style of advanced phantom has not yet been applied to oximetry, but could be highly beneficial in future studies that more closely resemble in vivo applications. [87]…”

“…This can enable oximetry in new applications, such as the study of small retinal vessels, [29] oximetry in infants, [68] in ex vivo red blood cells. [46] The advent of 3D printing has allowed the development of bio-mimicking phantoms [87] based on real blood vessel network patterns, [85] enabling the study of blood flow in realistic yet controlled scenarios. The fast paced development of 3D printing makes this field of phantom development particularly promising.…”

Low-Cost Eye Phantom for Stereophotogrammetry-Based Optic Nerve Head Topographical 3D Imaging

“…In both cases, the eye phantoms were very simplistic: they contained a single lens for refractive power, were air-filled and were not true to scale, thus incorrectly mimicking artefacts and aberration, hence of dubious validity for testing imaging devices designed for human eyes. More optically correct eye phantoms, fluid-filled, life-sized and containing two lenses to emulate the cornea and crystalline lens [9]- [11] have been developed for other purposes. These eye phantoms contained custom lenses, at very high cost and complexity.…”

Printed optics: phantoms for quantitative deep tissue fluorescence imaging

“…For example, printed phantoms of the human eye allow assessment of optical coherence tomography and related ophthalmic devices [7]. Additionally, printed phantoms formed from images of human vascular networks have allowed development of hyperspectral oximetry [8].…”