Aspects of the disclosed subject matter relate generally to eye pathology detection and monitoring, and more particularly to a system and method of corneal surface measurement that enables capture of corneal surface information for automated analysis.
Many pathologies affect the cornea. Some of these, like keratoconus, are treatable if the diagnosis is made while the patient remains young. Establishing these diagnoses has been the job of the trained clinician such as an ophthalmologist or an optometrist who has the requisite training and skill to make the appropriate determination. Tools employed by such clinicians include devices that measure the curvature of the surface of the cornea. These devices produce output that is interpretable by the clinician.
More recently, artificial intelligence and machine learning algorithms have been created that can aid in the interpretation of the display output that was originally designed for clinician interpretation. These algorithms suffer the disadvantage of interpreting displays or images that were originally created for human interpretation.
In some practical situations, by way of example, many cataract patients demonstrate evidence of a condition known as “dry eye” upon examination for cataract surgery. The majority of these patients are asymptomatic until testing. This ocular surface disease may result in inaccurate calculations for the power of intraocular lenses required, and may therefore result in a patient becoming unintentionally nearsighted or farsighted after cataract surgery. Remediation is possible, but only if this condition is detected before surgery.
By way of another example, in the case of contact lens fitting by optometrists, workflow inefficiencies exist that create undue expense and time commitments for both patients and care providers. Patients fit with contact lenses with which they are uncomfortable require increased time in office (e.g., known in the profession as “chair time”) with an optometrist, an ophthalmologist, or other care provider. As a result of discomfort, or frustration with conventional service paradigms, many contact lens wearers decline to continue wearing the devices within three years of agreeing to treatment. In some instances, it is believed that abnormalities of the tear film are associated with dissatisfaction experienced by contact lens wearers, but devices to measure tear quality (e.g., to quantify or otherwise to assess or to evaluate such tear film) over contact lenses are expensive and require substantial training, making determinations expensive and time consuming for both patient and care-giver.
By way of another example, keratoconus is a less common malady than the foregoing two conditions, but is equally identifiable and capable of being monitored by the subject matter disclosed below. Keratoconus is a progressive thinning and steepening of the cornea of a human eye, with a typical onset during the teenage years. New cross-linking therapy can stabilize the condition, but only in cases in which the diagnosis has been made. The chief problem is that although the age of onset is typically in a patient's teenage years, the mean age of diagnosis is a decade or more later, when patients present with more advanced disease than would be the case if the condition were detected earlier. Devices exist to detect keratoconus, but they are generally unavailable to pediatricians, and typically require substantial training in order to interpret the results that they generate.
There is, therefore, a need for an improved system and method employing data that have been captured in a manner designed for automated machine interpretation (e.g., a machine learning algorithm) which may then enable a device to render an interpretation of the acquired data. For example, it may be desirable in some instances to obtain (for subsequent processing) an image of a cornea or other body feature that is more advantageous for machine interpretation than it is for traditional interpretation methods that rely upon human intervention (and that only subsequently may be repurposed for machine ingestion).
The following presents a simplified summary of the disclosure in order to provide a basic understanding of some aspects of various embodiments disclosed herein. This summary is not an extensive overview of the disclosure. It is intended neither to identify key or critical elements of the disclosed embodiments nor to delineate the scope of those embodiments. Its sole purpose is to present some concepts of the disclosed subject matter in a simplified form as a prelude to the more detailed description that is presented later.
The present disclosure describes a system and method that are operative to gather data captured in a manner that is designed for automated machine interpretation. This feature may create an advantageous setting for a machine learning algorithm which may then render an interpretation of the data. Accordingly, an image may be created that is more advantageous for machine interpretation than traditional methods designed for human interpretation (where image data are later repurposed for use by machines or algorithms).
It will be appreciated that some advantages may include (but are not limited to) one or more of the following. By employing a light mask (an “optical mask” as described below) that incorporates many apices, an apex- and edge-rich corneal-reflected image may be captured. Circumferential displacement of these apices and edges is more evident than is available with traditional placido disk reflection techniques. In some implementations, artificial intelligence and machine learning algorithms may be employed to determine the probability of specific pathologies of the eye.
Implementations may include one or more of the following: illumination of the cornea of an eye using at least one light source oriented to pass light through an optical mask; alignment of a viewing portal to facilitate photography or other image capture of an image of the optical mask reflected from the cornea; and capture (for example, for further processing an interpretation) of image data related to a cornea-reflected image, for example, via a camera or other optical array.
In one embodiment, the light source and optical mask are contained within a portable housing. In one embodiment, the light source, optical mask, and at least one processor are contained within a portable housing. In one embodiment, the light source, optical mask, and at least one processor are contained within a desktop, table mounted, or device mounted housing.
In one embodiment, the optical mask comprises a plurality of transparent apertures comprising multiple apices. In one embodiment, the optical mask comprises a plurality of translucent apertures comprising multiple apices. In one embodiment, the optical mask comprises a plurality of transparent apertures comprising multiple edges. In one embodiment, the optical mask comprises a plurality of translucent apertures comprising multiple edges. In one embodiment, the optical mask comprises a plurality of transparent apertures comprising geometries optimized for machine learning ingestion of the captured image. In one embodiment, the optical mask comprises a plurality of translucent apertures comprising geometries optimized for machine learning ingestion of the captured image.
In accordance with one aspect of the disclosed subject matter, for example, a system of corneal (or other anatomical) surface measurement may generally comprise: a light source to transmit incident light through an optical mask, the optical mask comprising a light attenuation portion to impede transmission of the incident light and a plurality of apertures to allow transmission of a selected wavelength and intensity of the incident light; the plurality of apertures defining an image of a pattern that the incident light creates when it is cast on a portion of an anatomy of a patient; an image sensor to capture data representative of the image that is reflected from the anatomy of a patient; and a processing resource to assess a condition of the anatomy based upon the data.
Implementations are disclosed wherein the light source is operative to transmit the incident light in the selected wavelength, wherein ones of the plurality of apertures are transparent in the selected wavelength, and wherein ones of the plurality of apertures are translucent and operative to transmit only light having the selected wavelength.
Systems are disclosed wherein ones of the plurality of apertures comprise a plurality of apices, ones of the plurality of apertures comprise a plurality of edges, or both.
In some implementations, a system may further comprise a light diffusing element interposed between the light source and the optical mask. In some circumstances, it may be desirable that such a light diffusing element transmits the incident light in the selected wavelength.
Additionally or alternatively, a system as describe below may further comprise a lens to collimate the pattern on the image sensor. In some implementations, an image sensor is one of a charge-coupled device and a complementary metal oxide semiconductor sensor, though the following description is not so limited.
In accordance with another aspect of the disclosed subject matter, a method of corneal (or other anatomical) surface measurement may generally comprise: providing a light source to illuminate an area of a patient's anatomy with incident light of a selected wavelength and intensity; interposing an optical mask between the light source and the area; employing the optical mask to cast a pre-determined pattern of the incident light on the area; capturing an image of the pattern using an image sensor to create image data; and interpreting the image data to assess a condition of the area. In some instances, providing a light source may comprise transmitting the incident light in the selected wavelength.
Methods are disclosed wherein employing the optical mask comprises using a plurality of apertures to transmit the incident light in the selected wavelength. In that regard, some methods are disclosed wherein ones of the plurality of apertures are transparent in the selected wavelength, and wherein ones of the plurality of apertures are translucent and operative to transmit only light having the selected wavelength; combinations of the foregoing are contemplated as set forth below.
Some disclosed methods comprise employing a lens interposed between the area and the image sensor, the lens being operative to collimate the image of the pattern on the image sensor. Further methods are disclosed wherein capturing an image comprises using one of a charge-coupled device and a complementary metal oxide semiconductor sensor.
As will be more apparent from a review of the description to follow, in some embodiments, the systems and methods have utility in situations wherein the area (of a patient's anatomy sought to be imaged) is a cornea of an eye.
Certain aspects and features of the disclosed subject matter are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding thereof. It may be evident, however, that the innovative aspects may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate a description thereof. Specifically, the present disclosure provides for system and method of corneal surface measurement that may generally comprise hardware and software.
As set forth in more detail below, the present disclosure generally addresses acquisition of image data related to the curvature of a body part, such as a cornea of an eye, that are intended or optimized for ingestion by a machine learning or artificial intelligence algorithm, as opposed to being intended or optimized for review by a technician and then later repurposed or further processed for ingestion by such an algorithm.
In some implementations, artificial intelligence may achieve a simplification of interpretation to the point at which a device as described below may be used by a non-clinician; additionally or alternatively, analysis of the clinical image itself may be simplified, even for a trained clinician or other care giver. Conventional tools, primarily corneal topographers, exist that are adept at detecting keratoconus. These devices obtain a reflected image from a patient's cornea and produce a color-coded map to be interpreted by a clinician. The output displayed by such existing tools typically includes a number of calculated parameters that may aid the clinician in making a diagnosis. The aim of these devices is to produce output that is interpretable by a human, who may then make judgments based upon training and experience. To the extent that artificial intelligence (“AI”) has heretofore been employed to analyze such images, the AI has generally been made to ingest (i.e., to load, process, and to examine) the output and parameters that have been primarily produced for human interpretation. In essence, this requires two sets of mathematical computations: the first set is the translation of the reflected image from the cornea into an output that may be interpreted by a human clinician or care provider; the second represents a computation of that reflected image that is produced solely to allow a machine or an algorithm make an inference about the presence of a particular pathology.
In a departure from conventional methodologies, the approach set forth below is to have an AI engine (or algorithm, module, hardware component, software element, etc.) directly ingest the reflected image (i.e., the image reflected from a patient's cornea or other area of a patient's anatomy) without the cumbersome and inefficient intermediate task of producing a human-interpretable intermediate output. The advantages of the proposed approach are twofold: first, by reducing the computational load, the software and hardware may both be made much simpler, cheaper, and more compact; second, the intermediate output created by conventional corneal topography devices for human interpretation requires a great deal of technical training (both from an anatomical standpoint as well as from a device operation standpoint) to have any clinical value—this expertise (in anatomy, electronics, or both) may be minimized or avoided in the instant approach.
Specifically, employment of an AI engine or machine learning technologies may simplify the conventional process by supplying probabilities of the existence of a particular diagnosis in a straightforward manner that may be understood by a user with little to no clinical (or electro-mechanical) training. The present disclosure represents a novel approach to interpretation of ocular surface topography and pathology interpretation, and may be extended to areas of a patient's anatomy beyond the eye.
In that regard, conventional corneal topography devices are designed to facilitate the production of human-interpretable output, but are not optimized for ingestion by AI. As set forth below, one innovation described herein is to create a pattern to be projected onto the cornea, the reflection of which (by the cornea) is more ingestible by artificial intelligence than those currently produced by conventional devices. For instance, the conventional light pattern projected onto the surface of the cornea for diagnostic purposes is a series of concentric rings known as a placido disk. The historical basis for this has to do with the fact that a patient can view concentric rings and make judgments (and provide feedback to a clinician that is relevant to a diagnosis) based upon the patient's perception of the rings' distortion, if any. An inherent limitation in this diagnostic method, however, is that rings lack vertices or apices (corners), while it is features like edges and corners that facilitate computer-assisted image interpretation and analysis. By employing a reflectance mask (or “optical mask”) that is apex-rich, a pattern of incident light falling on a portion of a patient's anatomy (e.g., such as a cornea) may be produced that, while less interpretable to a human being, is more aligned with the sort of images that AI algorithms and machine learning engines require (or prefer) to make inferences or diagnostic suggestions. In some aspects of the present disclosure, such an apex-rich optical mask may present a significant distinction from conventional technologies.
In current ophthalmic treatment regimes, an eye's tear film is typically evaluated by measuring the amount of time that the film is stable before it spontaneously breaks up or decomposes. In the process of selectively projecting an apex-rich pattern of light (e.g., having a desired wavelength and intensity) over a large surface of the cornea, an AI engine or other algorithm may be enabled to distinguish patterns of breakup that may relate to (or provide insight into) a “dry eye” diagnosis.
Additionally, a system and method as set forth herein may be capable of mapping the tear film over a contact lens, and it is believed to be the case that the tear film break up pattern correlates with satisfaction and comfort of a particular patient with a particular contact lens. In this case, a clinician, optometrist, or other care provider may be able to select a compatible contact lens for a particular patient's cornea topography much more rapidly than is currently possible.
Turning now to the drawing figures,
As noted above, the optical mask 160 may generally be constructed such that the plurality of apertures 162 comprise geometries that are optimized for machine learning ingestion of an image captured by system 100. In one embodiment, the light source 104 may comprise light-emitting diodes 105, as noted above, though other light sources having utility in medical imaging or ophthalmic applications may also be used. In one embodiment, reference numeral 199 may refer to the cornea of an eye.
In operation, system 100 is operative to direct light from light source 104 through optical mask 160 (specifically, through apertures 162, while other light is attenuated by light attenuation portion 161) to a cornea 199 of an eye. Light reflecting off of cornea 199 is transmitted through viewing aperture 120 in optical mask 160 and through viewing aperture 110 in substrate 102 so as to be captured via a suitable imaging device as set forth in more detail below.
In one embodiment, a substrate 204 is provided with an aperture 210 arranged to align with a camera or visual array associated with or embodied in imaging device 299; in some implementations, this configuration may facilitate alignment of light reflected from cornea 199 such that the light traveling back to imaging device 299 (i.e., from right to left in
Without limiting the generalities of the foregoing, it will be appreciated that the optical mask 160 may be implemented to comprise a plurality of apertures 162 having geometries (both individually and collectively) that are favorable to or optimized for machine learning ingestion of the data captured by imaging device 299 related to an image of the cornea 199. Specific sizes, shapes, and geometries of the individual apertures 162, their relative transparency or translucency, and the relative placement of each in an array or field on optical mask 160 may be application-specific, or may vary as a function of the capture and processing capabilities of imaging device 299, the nature of the pathology sought to be detected, overall resolution of the image sought to be captured, manufacturing costs, material composition and other requirements, and other considerations related to construction and desired operational characteristics of optical mask 160, or a combination of these and a variety of other factors.
The
The foregoing and other hardware components, electronics, and necessary structural supports or ancillary functional and operational elements (such as electronic data busses, electrical connections, battery supplies, memory interfaces, electronic device controllers, and the like, some of which have been omitted from the drawings for clarity) may be supported or maintained in a housing or enclosure (generally identified at reference numeral 690). In that regard, housing 690 may be constructed of plastics, polymers, acrylics, metals or metal alloys, laminated materials such as fiberglass or carbon composites, or other materials generally known in the art and generally suitable for electronics and component manufacturing methodologies. The present disclosure is not intended to be limited by the nature or structural characteristics of the housing 690 that is used to enclose the operative components of system 600.
Similarly, power buttons (such as 601), power indicators (such as 602), charge indicators (such as 603), ventilation apertures (such as 604), ports (such as charging port 605 and data port 606), and electronic displays (such as 699) are generally known in the art, and are thus not described in more detail here for the sake of brevity. It is noted, however, that the size, placement, and relative orientations of these components (for example, positioning with respect to others of the features, components, buttons, or interface elements) on, in, or in connection with housing 690 are generally design choices and may be application-specific as a function of the overall desired operational characteristics or functionality of system 600, manufacturing costs, desired user interface (UI) or user experience (UX) requirements, specifications, or parameters, or a combination of these and a variety of other factors. For example, where display 699 is not a “touch-screen” or “touch-active” display, accommodations may be made for interface mechanisms (buttons, rocker panels, two-dimensional switches, and the like) to be disposed somewhere on housing 690 to enable a user to access and interact with the operational characteristics of system 600.
On the other hand, optical assembly (reference numeral 630) for acquiring the image data of a cornea 199 of an eye represents a departure from conventional technologies, and enables novel imaging and data capture. In that regard, housing 690 and the other components of system 600 (and, indeed, of systems 100, 200, and 400) are intended to be so sized, structured, positioned, and interconnected as to support operation of optical assembly 630 in any and all of the several implementations set forth herein. It will be appreciated that any of various alternatives may be employed for any given element of system 600, provided however, that optical assembly 630 is enabled to acquire image data of the cornea 199 substantially as illustrated and described.
In some implementations, housing 690 may include a distal portion 691; it will be appreciated that, in this context, “distal” refers to that portion of housing 690 that is furthest from an imaging device 299 (not shown in
Those of skill in the art will appreciate that processing resource 730 may generally comprise one or more microprocessors, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), programmable logic blocks, microcontrollers, or other digital processing apparatus suitable for image acquisition and data processing in accordance with requirements or design specifications of system 600. Typically, processing resource 730 may cooperate with or operate in connection with a memory structure or database (not shown in
It will be appreciated that image sensor 820 may be embodied in or comprise a CCD array, a multi-layer CCD array, a CMOS sensor, or a combination of these and other image sensing technologies; image sensor 820 may be referred to as a “camera” in some instances, but is not intended to be so limited. Similarly, macrophotography lens 830 may be embodied in or comprise any of myriad lenses or focusing or collimating assemblies operative to focus light reflected from a cornea 199 of an eye onto image sensor 820 in a desired manner. In that regard, the collimating qualities, focusing aspects, functional requirements, or other operational characteristics of macrophotography lens 830 may be application-specific in some instances, or may be selected as a function of cost, reliability, optical clarity or resolution, or as a combination of these and a variety of other factors. The present disclosure is not intended to be limited by the nature, functionality, or operational parameters of macrophotography lens 830 or image sensor 820.
In operation, these components of optical assembly 900 are to generate light at light source 104 (e.g., at a desired wavelength and intensity via light emitting diode 105 or some other suitable source, depending upon the nature of the light to be produced) which is diffused via light diffusing element 208 and cast upon optical mask 160. Optical mask 160, in turn, allows a cornea 199 of an eye to be illuminated via light transmitted through apertures 162 (which, as noted above, may be translucent or transparent, e.g., as a design choice or as an application-specific requirement, for instance, as a function of a specific ophthalmic pathology that is to be detected). In that regard, light that is incident on a cornea 199 may reflect back to macrophotography lens 830, which focuses the reflected light and transmits same (e.g., via apertures 120 and 220) to image sensor 820 for processing. This functionality and the interconnection of the various components are best illustrated in
It will be appreciated that, in
It is noted that a cornea 199 of an eye has been mentioned above, but other tissues, structures, or other surfaces of a patient (and other optical targets) are contemplated for operation of the disclosed systems and methods. While distal portion 691 of housing 690 is illustrated and described in connection with engaging anatomical structures near a human eye, the present disclosure is not intended to be so limited.
As noted above, system 600 may be configured and operative to receive input, feedback, operational parameters, and other instruction sets or commands from a user 1199 (e.g., via a touch screen display 699 or other user interface mechanism); additionally or alternatively, such a system 600 may be configured and operative to receive such instruction sets or commands from networked or remote compute resources such as server 1110 and artificial intelligence (AI) engine 1130 as set forth below. The bi-directional data communications pathways illustrated by the double arrows in
In operation, user 1199 of a system 600 that enables capture of corneal surface information for automated analysis may engage an interface provided at system 600 (such as via any of various and common user interface technologies, including without limitation, touch screen display 699) to initiate, terminate, or otherwise control capture of image data from an area of a patient's anatomy substantially as set forth above with reference to
In some implementations, data captured or received by, or otherwise transferred or input to, system 600 may comprise the name, address, license number, or other identifying information associated with the user 1199 of system 600, the name or corporate identification number of an entity employing or affiliated with the user 1199, the name, address, telephone number, credit card information, and insurance parameters for a patient who is the subject of the image data being acquired by system 600, and the like.
In accordance with some aspects of the present disclosure, system 600 in general, and processing resource 730, in particular, may be configured and operative (e.g., in cooperation with memory resources that are not illustrated in the drawing figures for clarity) to perform statistical and/or machine learning and and/or artificial intelligence analysis of captured images (such as image 1099, for instance). Such computing may be local (e.g., entirely resident on system 600, facilitated by processing resource 730), remote (e.g., executed at server 1110 or 1130, in cooperation with data on servers at data center 1120), or a combination of both. In any event, data representative of results or conclusions based upon such statistical analysis may be presented at system 600 (e.g., on a display screen 699), transmitted to or retained at server 1110 for subsequent analysis, transmission for display, or both, transmitted to AI engine 1130 to be used as seed data for further AI training, or a combination of any or all of the foregoing.
In this context, the server depicted at the upper right of
As noted above, it will be appreciated that server 1110, data center 1120, and AI engine 1130 may generally be embodied in or comprise a computer server, a desktop or workstation computer, a laptop or portable computer or tablet, or a combination of one or more of such components. In operation, these devices (individually or in cooperation) may be employed to initiate, instantiate, or otherwise to effectuate data processing operations as is generally known in the art. In that regard, these components 1110, 1120, and 1130 may be embodied in or include one or more physical or virtual microprocessors, FPGAs, application specific integrated circuits (ASICs), programmable logic blocks, microcontrollers, or other digital processing apparatus, along with attendant memory, controllers, firmware, and network interface hardware (not illustrated in
In operation, API 1212 may generally enable bi-directional data communication between system 600 (or other elements of system architecture 1200) and medical data management system 1214 (which, as noted above, may be controlled by a third party). In some implementations, such a patient medical data management system 1214 may be an electronic medical record system or an electronic health record system such as may be maintained by a county, state, or federal medical board, for example, or by a private research facility, university, medical practice, or for-profit life sciences research entity.
Method 1300 may continue by interposing an optical mask between the light source and the area to be illuminated, as indicated at block 1302. An optical mask, such as described above in connection with reference numerals 160, 161, and 162, may be manufactured of aluminum, stainless steel, nickel, or other suitable metals, for example; additionally or alternatively, some portions (or the entirety) of the structure of an optical mask may be constructed of ceramics, plastics, acrylics, or laminated materials such as fiberglass or carbon composites. In some implementations, apertures (such as described above in connection with reference numeral 162) may simply be holes or voids (i.e., spaces in optical mask 160 where there is no material at all); in other implementations, however, such apertures may include translucent materials (e.g., acrylics, glasses, plastics, etc.) that selectively allow transmission of incident light of a particular wavelength or intensity.
In the illustrated implementation, method 1300 may continue by employing the optical mask to cast a pre-determined pattern of the incident light on the area (block 1303); this operation may be selectively repeated as indicated by the dashed loop at reference numeral 1399. As noted above, this particular operation represents a departure from conventional methodologies which do not contemplate casting complex patterns of incident light on an area of a patient's anatomy (particularly a cornea 199 of an eye).
An image of the pattern of incident light (that is cast on the area of patient's anatomy) may be captured using an image sensor to create image data, as is indicated at block 1304. Many suitable image sensors (such as image sensor 820 described above) are known in the art to have sufficient functionality for this purpose; the present disclosure is not intended to be limited by the nature, functional characteristics, or specific technology employed by any particular image sensor employed to execute the functionality identified at block 1304.
Acquired image data may be interpreted to assess a condition (e.g., determine a pathology) of the area illuminated by the incident light, as indicated at block 1305. As noted above, conditions such as “dry eye” and keratoconus may be detected by the method of
It is noted that the arrangement of the blocks and the order of operations depicted in
Several features and aspects of a system and method have been illustrated and described in detail with reference to particular embodiments by way of example only, and not by way of limitation. Those of skill in the art will appreciate that alternative implementations and various modifications to the disclosed subject matter are within the scope and contemplation of the present disclosure. Therefore, it is intended that the present disclosure be considered as limited only by the scope of the appended claims.
This application claims the benefit of U.S. provisional patent application Ser. No. 63/349,085, filed Jun. 4, 2022, the disclosure of which is hereby incorporated herein by reference in its entirety.
Number | Date | Country | |
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63349085 | Jun 2022 | US |