US-20260123835-A1 - MULTIMODAL DEVICE FOR SPECTRAL AND OCT ACQUISITIONS

US20260123835A1US 20260123835 A1US20260123835 A1US 20260123835A1US-20260123835-A1

Abstract

A multimodal device for performing an assessment of the fundus of a patient's eye is provided. The multimodal device includes an imaging module producing an image representative of a first region of the fundus, a spectroscopy module producing a spectral analysis of a second region of the fundus and an OCT module producing depth-resolved information on a third region of the fundus. The second region is located within the first region, and the third region is at least partially located within the first region. Electromagnetic radiation travels from the fundus to the imaging module, spectral module and OCT module along an imaging path, a spectral path and an OCT path which a common light path segment leading to the fundus of the patient's eye.

Inventors

Nicolas LAPOINTE
Damon DEPAOLI
Dominic Sauvageau

Assignees

ZILIA INC.

Dates

Publication Date: 20260507
Application Date: 20231115

Claims (17)

1 . A multimodal device for performing an assessment of the fundus of a patient's eye, the multimodal device comprising: an imaging module comprising an imaging sensor having an angular field of view encompassing a first region of the fundus, the imaging sensor configured to receive electromagnetic radiation from said first region through an imaging path and to produce therefrom an-image representative of said first region; a spectroscopy module comprising a spectral analyzer having an angular field of view encompassing a second region of the fundus, the second region being located within the first region, the spectral analyzer configured to receive electromagnetic radiation from the second region of the fundus through a spectral path and to produce therefrom a spectral analysis of said second region; and an OCT module comprising an OCT detector having an angular field of view encompassing a third region of the fundus, the third region being at least partially located within the first region, the OCT detector configured to receive electromagnetic radiation from the third region of the fundus through an OCT path and to produce therefrom depth-resolved information on said third region; wherein the imaging path, the spectral path and the OCT path have a common light path segment leading to the fundus of the patient's eye.
2 . The multimodal device according to claim 1 , further comprising an illumination module comprising a non-coherent light source generating illumination light and optically coupled to the common light path segment for illuminating the first region of the fundus of the patient's eye with said illuminating light.
3 . The multimodal device according to claim 2 , wherein the spectroscopy module comprises an excitation light source generating an excitation light beam coupled to the spectral path for projecting on the second region of the fundus of the patient's eye.
4 . The multimodal device according to claim 2 , further comprising a pointer light source generating a pointer light beam coupled to the spectral path for projection on the second region of the fundus of the patient's eye.
5 . The multimodal device according to claim 1 , wherein the spectral analysis produced by the spectral module comprises a spectroreflectometric analysis.
6 . The multimodal device according to claim 1 , wherein the spectral analysis produced by the spectral module comprises a photoluminescence analysis.
7 . The multimodal device according to claim 1 , wherein the OCT module further comprises: an OCT light source configured to generate an OCT light beam having a short coherence length; a reference arm; and an OCT coupler configured to divide the OCT light beam into a first portion and a second portion and optically coupled to the OCT light path and to the reference arm; whereby the first portion of the OCT light beam is coupled into the OCT light path for projection on the third region of the fundus of the patient's eye, and the second portion of the OCT light beam is coupled into the reference arm.
8 . The multimodal device according to claim 7 , wherein the OCT module has a Time-Domain OCT configuration.
9 . The multimodal device according to claim 7 , wherein the OCT module has a Spectral Domain OCT configuration.
10 . The multimodal device according to claim 8 , further comprising a scanning module provided along the OCT path and configured to move the first portion of the OCT light beam across the fundus of the patient's eye, thereby defining the third region.
11 . The multimodal device according to claim 10 , wherein the spectral path and the OCT path have a shared spectral and OCT segment, and the scanning module is provided within the shared spectral and OCT segment.
12 . The multimodal device according to claim 11 , comprising: a primary beamsplitter connecting the imaging path and the shared spectral and OCT segment, the common light path segment extending between the primary beamsplitter and the fundus of the patient's eye; and a secondary beamsplitter connecting the spectral path and the OCT path, the shared spectral and OCT segment extending between the secondary beamsplitter and the primary beamsplitter.
13 . The multimodal device according to claim 1 , comprising: a primary beamsplitter coupling the spectral path and the imaging path, the common light path segment extending between the primary beamsplitter and the fundus of the patient's eye; and a secondary beamsplitter coupling the OCT light path to the imaging light path downstream of the primary beamsplitter.
14 . The multimodal device according to claim 17 , further comprising a controller generating control signals for controlling active components of the imaging module, spectral module, OCT module, illumination module and scanning module.
15 . The multimodal device according to claim 14 , wherein the controller is configured to operate the multimodal device to: a) acquire the image representative of said first region using the imaging module; b) identifying the second region and third region based on said image; c) acquire the spectral analysis of said second region; and d) acquire the depth-resolved information on the third region.
16 . The multimodal device according to claim 14 , wherein the controller is configured to operate the multimodal device in: an illumination mode wherein the controller operates the illumination light source to project said illumination light towards the patient's eye, the imaging device to obtain the image representative of said first region of the fundus and the spectral analyser to obtain said spectral analysis of said second region of the fundus; and an OCT mode wherein the controller operates the OCT light source, OCT detector and scanning module to obtain the depth-resolved image of the third region of the fundus.
17 . The multimodal device according to claim 10 , further comprising an illumination module comprising a non-coherent light source generating illumination light and optically coupled to the common light path segment for illuminating the first region of the fundus of the patient's eye with said illuminating light.

Description

TECHNICAL FIELD The technical field generally relates to imaging techniques and, more specifically, to devices and methods combining spectral information and optical coherence tomography (OCT), in particular of the eye fundus. BACKGROUND Ocular oximetry, that is, the measurement of the degree of oxygen saturation of blood in tissues of the eye, is a useful non-invasive tool with widespread medical and health monitoring applications. Indeed, measurement of oxygen saturation in biological tissues can provide valuable information on metabolism, responses to stress, the pathophysiology of different illnesses and conditions or the efficacy of administered treatments. Spectroreflectometric systems can be used to provide oximetry measurements or other information from the fundus of a patient's eye through a spectral analysis of light resulting from the interaction of illumination light with the fundus medium, or features in the eye fundus. For optimal use in the field, oximeters or similar devices and systems should preferably be efficient, simple to use and easy to manufacture. Low cost and miniaturisation of such equipment are also factors of interest. International patent application No. WO2019/109186 (PRIOR ART) teaches a spectroreflectometric system which provides a combined imaging and spectral analysis of the eye fundus. Advantageously, the disclosed system provides both a 2D image of the eye fundus as well as a spectral analysis at an analysis area on the fundus. A pointer mode allows for a user to visualize the position of the analysis area within the 2D image. In practice, fundus imagery based on the acquired 2D RGB images has been used for years by eye-care professionals to identify suspicious retinal features, for example associated with pathologies. For more specific information and metabolism-related information, additional tests are required, typically using different platforms. Optical coherence tomography (OCT) is typically used to show internal structural details, including in the area where the abnormal occurrence was identified. In addition to these techniques, diffuse reflectance spectroscopy enables the evaluation of specific biomarkers from a specific location, these biomarkers providing indications of the medical state of the patient. There remains a need for techniques acquiring multimodal information from a specific region of the eye fundus to provide a complete assessment of the state of the region, from oxygen saturation, retina thickness and blood flow. SUMMARY In accordance with one aspect, there is provided a multimodal device for performing an assessment of the fundus of a patient's eye, the multimodal device comprising: an imaging module comprising an imaging sensor having an angular field of view encompassing a first region of the fundus, the imaging sensor configured to receive electromagnetic radiation from said first region through an imaging path and to produce therefrom an image representative of said first region;a spectroscopy module comprising a spectral analyzer having an angular field of view encompassing a second region of the fundus, the second region being located within the first region, the spectral analyzer configured to receive electromagnetic radiation from the second region of the fundus through a spectral path and to produce therefrom a spectral analysis of said second region;an OCT module comprising an OCT detector having an angular field of view encompassing a third region of the fundus, the third region being at least partially located within the first region, the OCT detector configured to receive electromagnetic radiation from the third region of the fundus through an OCT path and to produce therefrom depth-resolved information on said third region;wherein the imaging path, the spectral path and the OCT path have a common light path segment leading to the fundus of the patient's eye. In some implementations, the multimodal device further comprises an illumination module comprising a non-coherent light source generating illumination light and optically coupled to the common light path segment for illuminating the first region of the fundus of the patient's eye with said illuminating light. In some implementations, the spectroscopy module comprises an excitation light source generating an excitation light beam coupled to the spectral path for projecting on the second region of the fundus of the patient's eye. In some implementations, the multimodal device further comprises a pointer light source generating a pointer light beam coupled to the spectral path for projecting on the second region of the fundus of the patient's eye. In some implementations, the spectral analysis produced by the spectral module comprises a spectroreflectometric analysis and/or a photoluminescence analysis. In some implementations, the OCT module further comprises: an OCT light source configured to generate an OCT light beam having a short coherence length;a reference arm; andan OCT