Fourier domain OCT device for optical retina imaging

Abstract

The invention relates to a Fourier domain OCT device for optical retinal imaging. A Fourier domain OCT apparatus for acquiring optical retinal imaging data includes a fixation target that fixes a gaze direction of an eye; an optical system that applies optical stimuli, the optical stimuli being restricted to a location-controllable partition of the retina of the eye; an OCT imaging system that acquires OCT data from the retina; and a controller that: acquires a target position on the retina; while the fixation target remains fixed relative to the position of the eye, using the target position to control the optical system to apply an optical stimulus to a first partition of the retina at the target position; controlling the OCT imaging system to acquire OCT data of a second partition of the retina, the second partition being stimulated by the applied optical stimulus during acquisition of the OCT data; and generating ORG data based on the acquired OCT data.

Description

[0001] field

[0002] Example aspects of the present invention generally relate to the field of optical coherence tomography (OCT) imaging systems, and specifically to Fourier domain OCT imaging systems for acquiring optical retinal imaging (optoretinography, ORG) data indicative of a physiological response of the retina of a subject's eye to optical stimulation.

[0003] background

[0004] Optical coherence tomography (OCT) is an imaging technique based on low-coherence interferometry that is widely used to acquire high-resolution two-dimensional and three-dimensional images of optically scattering media such as biological tissues.

[0005] Depending on how the depth measurement is achieved, OCT imaging systems can be classified as time domain OCT (TD-OCT) or Fourier domain OCT (FD-OCT) (also called frequency domain OCT). In TD-OCT, the optical path length of the reference arm of the interferometer of the imaging system varies with time during the acquisition of the reflectivity profile of the scattering medium imaged by the OCT imaging system (referred to herein as the "imaging target"), and the reflectivity profile is usually referred to as a "depth scan" or "axial scan" ("A scan"). In FD-OCT, the spectral interference pattern generated by the interference between the light in the reference arm of the interferometer and the light in the sample arm at each A scan position is Fourier transformed to simultaneously acquire all points along the depth of the A scan without any change in the optical path length of the reference arm. FD-OCT can allow much faster imaging than the scanning of the sample arm mirror in the interferometer because all back reflections from the sample are measured simultaneously. Two common types of FD-OCT are spectral domain OCT (SD-OCT) and swept source OCT (SS-OCT). In SD-OCT, a broadband light source delivers many wavelengths to the imaging target, and a spectrometer is used as a detector to measure all wavelengths simultaneously. In SS-OCT (also known as time-coded frequency-domain OCT), the light source is swept over a range of wavelengths, and the temporal output of the detector is converted into spectral interferometry.

[0006] Modern FD-OCT imaging systems are usually phase-stabilized. For example, SD-OCT imaging systems are inherently phase-stabilized due to the use of a line scan camera to acquire all spectral sampling points simultaneously. SS-OCT imaging systems can also be phase-stabilized by using phase stabilization techniques well known to those skilled in the art.

[0007] OCT imaging systems may also be classified as point scanning (also referred to as "point detection" or "scanning point"), line scanning, or full-field, depending on how the imaging system is configured to acquire OCT data at locations on an imaging target. Point scanning OCT imaging systems acquire OCT data by scanning across the surface of an imaging target with a focused sample beam, typically along a single line (which may be straight, or alternatively curved to define a circle or spiral) or a set of (usually substantially parallel) lines on the imaging target surface, and acquiring an axial depth profile (A-scan) for each of a plurality of points along the line, one point at a time, to create OCT data comprising a one-dimensional or two-dimensional array of A-scans representing a two-dimensional (i.e., B-scan) or three-dimensional (i.e., C-scan or volume scan) reflectance profile of the sample.

[0008] Line scan OCT imaging systems acquire OCT data by scanning with focused light across the surface of an imaging target. The measured reflectance from the imaging target is used to generate OCT data including a two-dimensional reflectance distribution (i.e., a B-scan) of the sample. By scanning with focused light across multiple locations on the imaging target, OCT data including a three-dimensional reflectance distribution (i.e., a C-scan or volume scan) of the sample can be obtained. Typically, the focused light is straight and is scanned in a direction perpendicular to it, although in some cases it can be curved and the scanning direction is adjusted accordingly. Full-field OCT imaging systems acquire OCT data by projecting a light beam onto an imaging target to acquire OCT data including a three-dimensional reflectance distribution (i.e., a C-scan or volume scan) of the sample.

[0009] Optical retinal imaging (ORG) generally refers to the detection of the physiological response of the retina of the eye to optical stimulation (i.e., the functional activity of the light-induced retina). ORG technology includes non-invasive optical imaging of this physiological response of the retina. For example, OCT imaging systems can be used to image retinal neurons that are believed to exhibit size (size) changes in response to the excitation of optical stimulation. These size changes have been shown to be detectable by OCT imaging systems, and are typically changes in the length of the outer segments of cone photoreceptors or rod photoreceptors in the retina, which are detected by measuring the axial depth changes of the inner and outer segments (IS / OS) of cone photoreceptors and the outer segment tips (COST) of cones or the IS / OS of rod photoreceptors and the outer segment tips (ROST) of rods. However, the detection of size changes of other retinal neurons (such as, for example, those neurons of retinal ganglion cells) has also been demonstrated with OCT imaging systems. When stimulated, the ganglion cell layer / inner plexiform layer (GCL / IPL) can also produce measurable thickness changes. The GCL and IPL tend to provide much weaker reflections, but these can also be detected, especially if steps are taken to suppress motion artifacts (see, for example, C. Pfāffle et al., “Simultaneous functional imaging of neuronal and photoreceptor layers inliving human retina,” Optics Letters, vol. 44, no. 23, pp. 5671-5674, published on December 1, 2019).

[0010] Existing ORG techniques that use an OCT imaging system to acquire ORG data indicating the physiological response of a portion of the retina to optical stimulation typically rely on a preliminary dark adaptation period of the retina to ensure that the retinal neurons are in an unstimulated state, wherein optical stimulation is subsequently applied to the retina within the full field of view of the OCT imaging system (i.e., the area of ​​the retina over which the OCT imaging system is operable to acquire OCT data when the eye is fixated on a fixation target). After acquiring ORG data at a first position on the retina, the retina must undergo another dark adaptation period before corresponding ORG data at each additional position on the retina can be acquired, because the entire retina is stimulated within the field of view of the OCT imaging system during the acquisition of ORG data at each position.

[0011] However, since the dark adaptation period is typically on the order of several minutes (e.g., about 5 minutes) or longer, repeating the dark adaptation period significantly increases the time it takes to acquire ORG data from different subregions of the retina. This can be tiresome for the patient and reduces the rate at which ORG data can be acquired from the patient, thereby limiting the rate at which the clinician can examine the patient.

[0012] Overview

[0013] According to a first exemplary aspect of the present invention, a Fourier domain optical coherence tomography (FD-OCT) device is provided, which is arranged to acquire optical retinal imaging (ORG) data indicating the physiological response of the retina of the subject's eye to optical stimulation. The FD-OCT device includes a fixation target, an optical system, an FD-OCT imaging system, and a controller. The fixation target is arranged to fix the gaze direction of the eye. The optical system is operable to apply an optical stimulus to the retina so that the illumination of the optical stimulus to the retina is limited to at least one partition of the retina, and the optical system can be controlled to change the position on the retina to which the optical stimulus is to be applied. The FD-OCT imaging system is operable to acquire OCT data by imaging the partitions of the retina of the eye. The controller is arranged to: acquire an indicator of a target position on the retina to which an optical stimulus is to be applied by the optical system; control the optical system using the acquired indicator to apply the optical stimulus to a first sub-region of the retina located at the target position while the position of the fixation target relative to the eye remains fixed; control the FD-OCT imaging system to acquire OCT data of a second sub-region of the retina, wherein at least a portion of the second sub-region of the retina is arranged relative to the first sub-region so as to be stimulated by the applied optical stimulus during acquisition of at least some of the OCT data; and generate ORG data based on the acquired OCT data.

[0014] In an example embodiment, the optical system may include a light source arranged to generate light providing optical stimulation, and one or more scanning elements arranged to direct the light to the retina, and the controller may be arranged to control the one or more scanning elements using the acquired indicators to direct the light to a first partition of the retina at the target location while the position of the fixation target remains fixed relative to the eye.

[0015] In an example embodiment, the FD-OCT imaging system may include: an interferometer having a sample arm and a reference arm; and a detector arranged to detect interference between sample OCT light propagating along the sample arm after having been scattered from the retina and reference OCT light propagating along the reference arm, wherein at least one of the one or more scanning elements is also arranged to direct the sample OCT light toward a second partition of the retina and to direct the sample OCT light scattered from the second partition of the retina toward the detector.

[0016] Alternatively, the FD-OCT imaging system of the example embodiments may include: an interferometer having a sample arm and a reference arm; one or more scanning elements; and a detector arranged to detect interference between sample OCT light propagating along the sample arm after having been scattered from the retina and reference OCT light propagating along the reference arm, wherein the one or more scanning elements are arranged to direct the sample OCT light toward a second subdivision of the retina and to direct the sample OCT light scattered from the second subdivision of the retina toward the detector, and wherein the one or more scanning elements of the optical system are different from the one or more scanning elements of the FD-OCT imaging system. In this case, the controller may be arranged to use the acquired indicator to control the one or more scanning elements of the optical system independently of the one or more scanning elements of the FD-OCT imaging system while the position of the fixation target relative to the eye remains fixed.

[0017] According to another example embodiment, the controller may be arranged to: acquire a plurality of indicators, each indicating a respective target position on the retina to which an optical stimulus is to be applied by the optical system; control the optical system to apply the optical stimulus using the acquired indicators while the position of the fixation target relative to the eye remains fixed so as to confine the optical stimulus to respective independent first subareas of the retina at respective target positions; control the FD-OCT imaging system to acquire, for each of the first subareas of the retina, respective OCT data of respective second subareas of a plurality of second subareas of the retina, wherein at least a portion of the respective second subarea of ​​the retina is disposed relative to the respective first subarea of ​​the retina so as to be stimulated by the applied optical stimulus during acquisition of at least some of the respective OCT data; and process the respective OCT data of each second subarea of ​​the retina to generate respective ORG data indicating respective physiological responses of the second subarea of ​​the retina to the optical stimulus applied to the corresponding first subarea of ​​the retina. Additionally, within a period of no more than 3 seconds: the controller may be arranged to control the optical system using the acquired indicators to apply the optical stimulus to the respective first subareas of the retina; and the controller may be arranged to control the FD-OCT imaging system to acquire respective OCT data of each of the first subareas of the retina.

[0018] In another example embodiment, the controller may be further arranged to: for each second sub-division of the retina, store the corresponding ORG data generated for the second sub-division in association with a corresponding indication of the position of a point in the field of view of the eye that is optically conjugate with the corresponding position of the second sub-division on the retina. In this case, the controller may be further arranged to: determine, for each of a plurality of points in the field of view of the eye, a corresponding indication of the corresponding position on the retina that is optically conjugate with the point, a corresponding indication of the position of each second sub-division of the retina at which OCT data is to be acquired by the FD-OCT imaging system; and determine, based on the corresponding indication in the determined indication indicating the position of the corresponding second sub-division of the retina, each indicator of a plurality of indicators, wherein at least a portion of the corresponding second sub-division of the retina is arranged relative to the first sub-division (the position of which is indicated by the indicator) so as to be stimulated by the applied optical stimulus during the acquisition of at least some of the OCT data. Alternatively, the controller may also be arranged to: acquire a plurality of indicators based on an image of the retina of the eye; determine, based on corresponding indicators among the plurality of indicators, a corresponding indication of the following position on the retina for each second partition of the retina: at which position OCT data will be acquired by the FD-OCT imaging system; and for each second partition of the retina, determine a corresponding indication of the position in the field of view of the eye of a point that is optically conjugate with the position of the second partition on the retina.

[0019] In another example embodiment set forth above or any variation thereof, the FD-OCT apparatus may further include a display device, and the controller may further be arranged to acquire data indicating how the measurement results of the subject's ability to see optical stimuli of corresponding different partitions on the retina confined to different corresponding positions of the retina of the eye are distributed over at least a portion of the field of view of the eye. The controller may acquire the data by: receiving a corresponding indication provided by the subject as to whether the subject sees a corresponding optical stimulus of each of a plurality of first partitions of the retina applied by the optical system to the retina; associating each of the received indications with a corresponding indication of the position of the corresponding first partition on the retina; and for each corresponding indication of the position of the corresponding first partition on the retina, determining a corresponding indication of the position of a point in the field of view of the eye that is optically conjugate with the position of the corresponding first partition on the retina. Alternatively, the controller may acquire the above data by receiving field of view test data that has been acquired from the eye. In either case, the controller may also be arranged to control the display device to display a first graph based on at least some of the acquired data, the first graph indicating how the subject's ability to see the optical stimulus (indicated by at least some of the acquired data) is distributed over at least a portion of the eye's field of view; and to control the display device based on at least some of the stored ORG data and the associated stored indications to display a second graph for comparison with the first graph, the second graph indicating how the retina's physiological response to the optical stimulus (indicated by at least some of the stored ORG data) is distributed over at least a portion of the eye's field of view. For example, the first graph and the second graph may be displayed side by side or (at least partially) superimposed on each other on the display device.

[0020] Alternatively, in another example embodiment set forth above, the controller may also be arranged to: for each of a plurality of second partitions of the retina, store corresponding ORG data generated from OCT data acquired from the second partition in association with a corresponding indication of the position of the second partition on the retina; and acquire data indicating how measurements of the subject's ability to see optical stimuli of corresponding different partitions on the retina confined to different corresponding positions of the retina of the eye are distributed over at least a portion of the field of view of the eye. The controller may be arranged to acquire the data by: receiving field of view test data acquired from the eye by a field of view test device, the field of view test data comprising measurements of the subject's ability to see optical stimuli applied from a plurality of points in the field of view of the subject's eye; and for each of a plurality of points in the field of view of the eye, determining a corresponding indication of a corresponding position on the retina that is optically conjugate with the point. Alternatively, the controller may be arranged to acquire the aforementioned data (the data indicating how the measurement results of the subject's ability to see optical stimuli of respective different subareas on the retina confined to different respective positions of the retina of the eye are distributed over at least a portion of the retina) by: receiving an indication provided by the subject as to whether the subject sees the respective optical stimuli of each of the first subareas applied to the retina by the optical system; and associating each of the received indications with a respective indication of the position of the respective first subarea on the retina. In either case, the FD-OCT apparatus may further include a display device, and the controller may be further arranged to control the display device based on at least some of the acquired data to display a first map indicating how the subject's ability to see optical stimuli with the eye is distributed over at least a portion of the retina of the eye; and to control the display device based on at least some of the generated ORG data and the position of the second subarea of ​​the retina from which at least some of the ORG data is generated to display a second map for comparison with the first map, the second map indicating how the response of the retina to the optical stimuli indicated by at least some of the generated ORG data is distributed over at least a portion of the retina of the eye.

[0021] The controller may also be arranged to compare the data of the first map with the data of the second map, and based on the comparison, identify at least one of the following: (i) one or more first regions of at least a portion of the visual field, indicating that the subject is able to see the optical stimulus in the one or more first regions of the at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provide a physiological response to the optical stimulus that satisfies a predetermined condition; (ii) one or more second regions of at least a portion of the visual field, indicating that the subject is unable to see the optical stimulus in the one or more second regions of the at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provide a physiological response to the optical stimulus that satisfies a predetermined condition. provides a physiological response to the optical stimulus that satisfies a predetermined condition; (iii) one or more third areas of at least a portion of the visual field, indicating that the subject is able to see the optical stimulus in the one or more third areas of the at least a portion of the visual field, and indicating that one or more corresponding areas of the retina provide a physiological response to the optical stimulus that does not satisfy the predetermined condition; and (iv) one or more fourth areas of at least a portion of the visual field, indicating that the subject is unable to see the optical stimulus in the one or more fourth areas of the at least a portion of the visual field, and indicating that the one or more corresponding areas of the retina provide a physiological response to the optical stimulus that does not satisfy the predetermined condition.

[0022] In the foregoing, each first subdivision of the retina may be smaller than an area of ​​the retina on which the FD-OCT imaging system is operable to acquire OCT data.

[0023] According to a second exemplary aspect of the present invention, a method for acquiring ORG data is provided, the ORG data indicating a physiological response of the retina of an eye to an optical stimulus, the method comprising: acquiring an indicator of a target position on the retina to which the optical stimulus is to be applied; applying the optical stimulus to a first partition of the retina located at the target position using the acquired indicator while the gaze direction of the eye remains fixed; acquiring OCT data of a second partition of the retina, wherein at least a portion of the second partition of the retina is arranged relative to the first partition so as to be stimulated by the applied optical stimulus during at least some of the acquisition of the OCT data; and generating ORG data based on the acquired OCT data. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Example embodiments will now be explained in detail, by way of non-limiting example only, with reference to the accompanying drawings described below.Unless otherwise indicated, like reference numerals appearing in different figures of the drawings may represent the same element or a functionally similar element.

[0026] Figure 1 is a schematic diagram of an FD-OCT apparatus 100 according to an example embodiment herein.

[0027] Figure 2 is a schematic front view of a display device 200 of the FD-OCT apparatus 100 , which displays a graphic 210 as an example of a fixation target for fixing the gaze direction of the eye.

[0028] Figure 3A is a schematic diagram of an optical system 300 and a FD-OCT imaging system 320 according to example embodiments herein.

[0029] Figure 3B is a schematic diagram of an example optical system 330 and an example FD-OCT imaging system 331 that share an example scanning system 332 that includes lens-based optics rather than Figure 3A The curved mirrors 313 and 315 in FIG.

[0030] Figure 3C is a schematic diagram of an optical system 340 and a FD-OCT imaging system 341 according to an alternative implementation of example embodiments herein.

[0031] Figure 3D is a schematic diagram of an example optical system 350 and an example FD-OCT imaging system 351 that share an example scanning system 352 that includes lens-based optics rather than Figure 3C The curved mirrors 313 and 315 in FIG.

[0032] Figure 3E is a schematic diagram of an optical system 360 and a FD-OCT imaging system 361 according to another alternative implementation of an example embodiment.

[0033] Figure 3F is a schematic diagram of an example optical system 370 and an example FD-OCT imaging system 371 that share an example scanning system 372 that uses a two-dimensional scanner 373 instead of Figure 3E The third scanning element 363 and the fourth scanning element 364 in.

[0034] Figure 4 is a schematic diagram of programmable signal processing hardware that may be configured to perform the functions of controller 140 described herein.

[0035] Figure 5 is a flow chart illustrating a process by which the controller 140 generates the ORG data 150 according to an example embodiment herein.

[0036] Fig. 6A , Figure 6B and Figure 6C is performed using the optical system 300 and the FD-OCT imaging system 320 of the exemplary embodiment. Figure 5 Schematic diagram of example first and second subareas of the retina during processes S52 and S53.

[0037] Fig.6D and Fig. 6E is using Figure 3E The optical system 360 and the FD-OCT imaging system 361 perform Figure 5 Schematic diagram of example first and second subareas of the retina during processes S52 and S53.

[0038] Fig. 6F is used Figure 3C The optical system 340 and the FD-OCT imaging system 341 perform Figure 5 Schematic diagram of the first partition and the second partition during processes S52 and S53 in FIG.

[0039] Figure 7 is a flow chart illustrating a process by which the controller 140 may generate ORG data 150 for multiple locations on the retina.

[0040] Fig. 8A shows the execution during an ORG data capture session Figure 7 The example plurality of first partitions 801 to 807 and the example plurality of second partitions 811 to 817 during processes S72 and S73.

[0041] Figure 8B shows the execution during an ORG data capture session Figure 7 The example plurality of first partitions 821 to 824 and the example plurality of second partitions 825 to 824 during processes S72 and S73.

[0042] Figure 8C shows the execution during an ORG data capture session Figure 7 The example plurality of first partitions 831 to 834 and the example plurality of second partitions 835 to 838 during processes S72 and S73.

[0043] Fig.8D shows the execution during an ORG data capture session Figure 7 The example plurality of first partitions 841 to 844 and the example plurality of second partitions 845 to 848 during processes S72 and S73.

[0044] Fig. 8E shows the execution during an ORG data capture session Figure 7 The example multiple first partitions 851, 852, 855 and 856 and the example multiple second partitions 853, 854, 857 and 858 during processes S72 and S73.

[0045] Fig. 9 shows the execution during an ORG data capture session Figure 5 Processes S52 and S53 in Figure 7 The example first partition 901 and the example second partition 902 during processes S72 and S73 in FIG.

[0046] Fig.10 shows the execution during an ORG data capture session Figure 5 Processes S52 and S53 in Figure 7 The example first partition 1001 and the example second partition 1002 during processes S72 and S73 in FIG.

[0047] Fig.11 is a flow chart illustrating a process by which the controller 140 of an example embodiment may determine an indicator of a target location on the retina to which an optical stimulus is to be applied based on a point in the field of view of the eye.

[0048] Fig.12 is a flow chart illustrating a process by which the controller 140 may select indicators and corresponding locations where OCT data is to be acquired, and map locations on the retina where OCT data has been acquired to corresponding locations in the eye's field of view.

[0049] Fig.13 is a schematic diagram of a data structure 1300 that may be stored by the controller 140, wherein respective ORG data generated for each of a plurality of independent partitions of the retina is stored in association with respective indications of the position of a point in the field of view of the eye that is optically conjugate with the position of the partition.

[0050] Fig.14 is a flow chart showing a process by which a controller 140 acquires data indicating how measurements of a subject's ability to see optical stimuli applied to corresponding different locations on the retina of the eye are distributed over at least a portion of the eye's field of view, and controls a graph display device 142 to display the graph described herein.

[0051] Fig.15 A flow chart is shown which illustrates that the controller 140 may Fig.14 The process of obtaining data in process S1401.

[0052] Fig.16 An example first graph 1400 is shown, which may be viewed at Fig.14 The process S1402 is displayed by the diagram display device 142.

[0053] Fig.17 An example second graph 1500 is shown, which may be viewed at Fig.14 The process S1403 is displayed by the graph display device 142.

[0054] Fig.18 An example third graph 1600 is shown, which may be viewed at Fig.14 The process S1405 is displayed by the graph display device 142.

[0055] Fig.19 is a flow chart showing a process by which controller 140 can acquire data indicating how measurements of a subject's ability to see optical stimuli applied to corresponding different locations on the retina of eye 160 are distributed over at least a portion of the retina of eye 160, and controller 140 controls image display device 142 to display the fourth and fifth images described herein.

[0056] Fig. 20A The display controller 140 can be Fig.19 Flow chart of the process of acquiring data in process S2102.

[0057] Fig. 20B The display controller 140 can be Fig.19 Flow chart of an alternative process for obtaining data in process S2102.

[0058] Fig.21 An example fourth graph 1700 is shown, which may be viewed at Fig.19 The process S2103 is displayed by the graph display device 142.

[0059] Fig. 22 An example fifth graph 1800 is shown, which may be viewed at Fig.19 The process S2104 is displayed by the diagram display device 142.

[0060] Fig.23A is a schematic diagram of a rotatable wedge prism that can be controlled to set the location on the retina of eye 160 where optical stimulation is to be applied.

[0061] Fig. 23B is a schematic diagram of a Risley prism scanner that can be controlled to set the location on the retina of eye 160 where an optical stimulus is to be applied.

[0062] Fig.24 is a schematic diagram of an alternative optical arrangement including optical fibers and one or more lenses that may be used to locate a location on the retina of eye 160 to which optical stimulation is to be applied.

[0063] Fig.25 is a schematic diagram of another alternative optical arrangement including a dynamic amplitude mask and a beam steering mechanism that can be used to set the location on the retina of eye 160 to which optical stimulation is to be applied.

[0064] Detailed Description of Example Embodiments

[0065] In view of the above-mentioned problems of using repeated dark adaptation periods to acquire ORG data at multiple locations on the retina, the present inventors designed a Fourier domain optical coherence tomography (FD-OCT) device, which is arranged to acquire optical retinal imaging (ORG) data indicating the physiological response of the retina of the eye to optical stimulation, and the FD-OCT imaging device includes an optical system that is operable to apply optical stimulation to the retina so that the illumination of the retina by the optical stimulation is limited to a subregion of the retina, and is controllable to change the position on the retina to which the optical stimulation is to be applied.

[0066] Thus, by controlling the optical system, optical stimulation can be applied to a localized partition of the retina (but not to the surrounding area of ​​the retina), and can be applied to different partitions on the retina at different locations of the retina within the field of view of the FD-OCT imaging device. Thus, after a single dark adaptation period, the optical stimulation can stimulate multiple different partitions of the retina, while the optical stimulation applied to any partition does not stimulate any other partition of the retina. This can allow accurate, comparable ORG data to be acquired at each location of the partition without the need for additional dark adaptation periods or repeated patient alignments, which can make the acquisition of ORG data easier to automate and significantly reduce the time spent acquiring ORG data. Faster acquisition of ORG data can improve patient comfort by reducing the time the patient spends in front of the FD-OCT device, thereby reducing the tendency for the patient to move and thereby reduce the quality of the ORG data. In addition, the rate at which a patient can be imaged using the FD-OCT device can be increased, thereby increasing the rate at which a clinician can evaluate a patient using the FD-OCT device.

[0067] Furthermore, a less powerful light source can be used to generate the optical stimulation, which may be more comfortable for the patient, than is conventionally the case where the optical stimulation is applied to the full field of view of the OCT imaging system. By limiting the optical stimulation to a localized subregion of the retina, a sufficiently high irradiance to that subregion of the ORG can also be achieved, but using a less powerful light source.

[0068] Example embodiments of the aforementioned FD-OCT imaging apparatus will now be described in detail with reference to the accompanying drawings.

[0069] Figure 11 is a schematic diagram of an FD-OCT apparatus 100 arranged to acquire optical retinal imaging (ORG) data 150 indicative of a physiological response of a retina of an eye 160 of a subject to an optical stimulus according to an example embodiment of the present invention. The FD-OCT apparatus 100 includes a fixation target 110, an optical system 120, a FD-OCT imaging system 130, a controller 140, and an optional image display device 142.

[0070] The fixation target 110 is arranged to fix the gaze direction 161 of the eye 160 (i.e., the direction away from the eye 160 along the visual axis of the eye 160). Such fixation may occur when the eye 160 is fixated on the fixation target 110. That is, during the acquisition of the ORG data 150, the fixation target 110 is arranged to be visible to the eye 160 so as to fix the gaze direction 161 of the eye 160 when being fixed on by the eye 160. However, the fixation target 110 may alternatively be arranged to fix the gaze direction 161 of the other eye 160 when one eye of the subject is fixed on the fixation target 110. In most subjects without strabismus or the like, the muscles controlling eye movement work together and point both eyes in the same direction, so that the fixation of the gaze direction of one eye by the fixation target 110 causes the other eye (even if the other eye cannot see the fixation target 110) to have the same gaze direction. For example, in the case where the eye 160 is the right eye of the subject, the gaze direction 161 of the eye 160 may be fixed by fixing the subject's left eye on the fixation target 110. As in the present example embodiment, the position of the fixation target 110 relative to the eye 160 may be controlled by the controller 140 so as to control the gaze direction 161 of the eye 160 when the eye 160 is fixated on the fixation target 110. However, during manufacture or installation / setting of the FD-OCT imaging system 130, the position of the fixation target 110 may alternatively be set at a fixed position relative to the expected position of the eye 160 (i.e., the position where the eye 160 is placed relative to the FD-OCT imaging system 130 for the FD-OCT imaging system 130 to acquire the AS-OCT image). The fixation target 110 may be integrated into the FD-OCT device 100 to be visible to the eye 160 in various ways known to those skilled in the art or as described in US Pat. No. 11,253,146 B2, the contents of which are hereby incorporated by reference in their entirety.

[0071] Figure 2is a schematic diagram of an example implementation of a fixation target 110 in the form of a graphic 210 displayed by a display device 200 forming part of the FD-OCT apparatus 100. The display position of the graphic 210 relative to the eye 160 can be controlled by the controller 140 to control the gaze direction 161 of the eye 160 when the eye 160 gazes at the graphic 210. In other words, the position of the eye 160 relative to the FD-OCT imaging system 130 is fixed (e.g., by placing the patient's chin on the chin rest of the FD-OCT imaging system 130), and the display position of the graphic 210 on the display area of ​​the display device 200 is adjustable, such as Figure 2 As shown by the arrow in , in order to set (manipulate) the gaze direction 161 of the eye 160 when the eye 160 gazes at the graphic 210. Although the graphic 210 is Figure 2 The graphic takes the form of dots, but it should be understood that the form of the graphic is not limited to this and can alternatively be provided in the form of a cross, a circle, or any shape that the eye 160 can focus on.

[0072] Furthermore, the fixation target 110 may be implemented in a form different from the graphic displayed by the display device 200. For example, the fixation target 110 may include a light source (e.g., a light emitting diode) attached to an actuator that may be controlled by the controller 140 to move the light source relative to the eye 160, thereby controlling the gaze direction 161 of the eye 160 when the eye 160 is fixated on the light source.

[0073] The optical system 120 is operable to apply optical stimulation to the retina of the eye 160 such that illumination of the retina by the optical stimulation is limited to (and may span or fill) a sub-area of ​​the retina, and the optical system 120 is controllable to change the location on the retina of the eye 160 where the optical stimulation is to be applied while the gaze direction of the eye 160 is fixed by the fixation target 110. In other words, the optical system 120 is controllable to apply the optical stimulation to each of a plurality of different sub-areas of the retina of the eye 160, whereby when the optical stimulation is applied to a sub-area of ​​the plurality of sub-areas of the retina of the eye 160, the optical stimulation is not applied to any other sub-area of ​​the plurality of sub-areas of the retina. As described in more detail below, the optical system 120 is controllable to change the location on the retina where the optical stimulation is to be applied while the position of the fixation target 110 relative to the eye 160 remains fixed (and the gaze direction 161 of the eye 160 remains fixed to the fixation target 110).

[0074] As in the present example embodiment, the optical stimulus may be a flash of predetermined duration applied to the retina of the eye 160 along the optical path 121 of the optical system 120. The duration of the flash is typically much shorter than the time period over which the OCT data is acquired by the FD-OCT imaging system 130 to generate the ORG data 150, and may depend on the intensity of the stimulus. For example, the duration of the flash may be between 5 ms and 50 ms. As described in more detail below, the duration of the optical stimulus may be controlled by the controller 140.

[0075] As in the present example embodiment, the FD-OCT imaging system 130 (which may be a phase-stabilized FD-OCT imaging system) may be a point scanning FD-OCT imaging system. However, the FD-OCT imaging system 130 may take other forms, such as a line scan or full field FD-OCT imaging system. The FD-OCT imaging system 130 is operable to acquire composite OCT data 135 by imaging a subarea of ​​the retina of the eye 160. As in the present example embodiment, the OCT data 135 may include a time series of OCT images, such as, for example, a time series of A-scans, B-scans, or C-scans.

[0076] Figure 3A 3 is a schematic diagram of an optical system 300 and an FD-OCT imaging system 320. In the present exemplary embodiment, the optical system 300 and the FD-OCT imaging system 320 may form Figure 1 1 and 2. The optical system 300 includes a light source 301, and the FD-OCT imaging system 320 includes an OCT light source 321, an interferometer 322, and a detector 323. As described below, the scanning system 310 is shared by the optical system 300 and the FD-OCT imaging system 320, and includes a beam splitter 311, a first scanning element 312, a first curved mirror 313, a second scanning element 314, and a second curved mirror 315. Although not shown in FIG. 1 for clarity, the scanning system 310 is not shown in FIG. Figure 3A 314, but the fixation target can be located in the scanning system 310, on at least one side of the first curved mirror 313, above and / or below the plane of the figure, as described in US 11,253,146 B2. Therefore, light from such a fixation target can be passed to the eye 160 via the second scanning element 314 and then via the second curved mirror 315.

[0077] The OCT light source 321 of the FD-OCT imaging system 320 is arranged to generate an OCT beam L b As in the present example embodiment, the OCT light source 321 may include an illumination source and an illumination source aperture. In this case, the illumination source is arranged to emit light through the light source aperture to generate the OCT light beam L b, so that the shape and size of the illumination source aperture (e.g., the diameter in the case where the light source aperture is circular) defines the OCT beam L b The cross-sectional shape and size (e.g., diameter) of the FD-OCT imaging system 320 (i.e., such that these sizes and shapes are the same). In the case where the FD-OCT imaging system 320 is a swept source OCT (SS-OCT) imaging system, the illumination source can be arranged to generate light having a certain wavelength that is swept over a range of wavelengths during a scan performed by the SS-OCT imaging system, or in the case where the FD-OCT imaging system 320 is a spectral domain OCT (SD-OCT) imaging system, the illumination source is a broadband light source that is arranged to simultaneously generate light having a range of wavelengths (i.e., broad spectral content) during a scan performed by the SD-OCT imaging system. The illumination source can be any known swept source or broadband source, as the case may be. For example, the illumination source can include a laser or a light emitting diode.

[0078] For example, the OCT light source 321 may include additional components, such as one or more collimating lenses for collimating light from the light source. In addition, as will be readily appreciated by those skilled in the art, the OCT light source 321 may alternatively take other forms, where the FD-OCT imaging system 320 is a line-field or full-field FD-OCT imaging system. For example, where the FD-OCT imaging system 320 is a line-field FD-OCT imaging system, the OCT light source 321 may be arranged to generate light and may include a laser and one or more cylindrical lenses (e.g., a combination of a plano-concave lens and a plano-convex lens, which are arranged to focus a light beam from a laser in respective directions orthogonal to each other to form light), but any other type of spatial light modulator known to those skilled in the art for beam shaping may also be used instead.

[0079] The interferometer 322 is arranged to transmit the OCT light beam L from the OCT light source 321 to b The light L is divided into the sample OCT light L and propagates along the sample arm 324 of the interferometer 322. o , and propagates along the reference arm 325 of the interferometer 322 as the reference OCT light L r The interferometer 322 is also arranged to receive light L that has been scattered by a subarea of ​​the retina of the eye 160 and collected by the scanning system 310. c , to generate the reference OCT light L r and the collected light L c The interference light L I , and the interference light L I The reference OCT light L transmitted along the reference arm 325 during the scan performed by the FD-OCT imaging system 320 is output to the detector 323. rand collected light L which has been scattered by a partition of the retina of the eye 160 and collected by the scanning system 310 c are guided to coincide and interfere with each other, and the resulting interference light L I is guided to the detector 323 and received by the detector 323 .

[0080] As in the present example embodiment, the interferometer 322 may be a Michelson interferometer that uses a beam splitter 326 to separate the OCT beam L b The reference OCT light L that has been reflected from the reference mirror 327 propagates along the sample arm 324 and the reference arm 325 of the interferometer 322. r and the collected light L from the scanning system 310 c Interference. Although a Michelson interferometer has been described, those skilled in the art will recognize that the interferometer 322 is not limited thereto and that any interferometer suitable for OCT, such as, for example, a Mach-Zehnder interferometer, may be used. Furthermore, those skilled in the art will recognize that in the case where the FD-OCT imaging system 320 is a line scan or full-field FD-OCT imaging system, the interferometer 322 may also be appropriately adapted. For example, in the case where the FD-OCT imaging system 320 is a line scan FD-OCT imaging system, the interferometer 322 may be a free space interferometer using at least one beam splitter. Furthermore, the interferometer 322 is not limited to a free space interferometer, but may be a fiber-based interferometer. In this case, the interferometer may employ a fiber coupler to separate the OCT beam L b The reference light L r and collect light L c Interference occurs.

[0081] The scanning system 310 is arranged to perform a sample OCT scan on a sub-area of ​​the retina of the eye 160. o 160 and collects light L that has been scattered by a subarea of ​​the retina of the eye 160 during the point scanning. c Thus, the scanning system 310 is arranged to acquire (e.g., one-dimensionally or two-dimensionally) A-scans at corresponding scanning positions distributed over a sub-area of ​​the retina of the eye 160 by: o The scanning positions are illuminated sequentially, one at a time, and light L scattered by a subarea of ​​the retina of the eye 160 at each scanning position is collected. c By acquiring successive A scans, the scanning system 310 is thus able to acquire a B scan and / or a C scan of the retina of the eye 160.

[0082] Sample OCT light L o From the interferometer 322, it enters the scanning system 310 and propagates to the beam splitter 311. The sample OCT light L o Then, it is reflected by the first scanning element 312, the first curved mirror 313, the second scanning element 314, and the second curved mirror 315 in sequence, and then is incident on the partition of the retina of the eye 160. The light L that has been scattered by the partition of the retina of the eye 160 and collected by the scanning system 310 c Along with the sample OCT light L o The same optical path passes through scanning system 310 but in reverse order and exits scanning system 310 after having propagated via beam splitter 311 .

[0083] Point scanning is performed by the scanning system 310 in the following manner: the first scanning element 312 rotates around a first axis (not shown) to scan the sample OCT light L in a first direction or a direction opposite to the first direction on a sub-area of ​​the retina of the eye 160. o , and / or the second scanning element 314 rotates about the second axis 316 to scan the sample OCT light L in a second direction or in a direction opposite to the second direction on a subarea of ​​the retina of the eye 160 o As in the present example embodiment, the second direction may be orthogonal to the first direction. Therefore, by rotating the first scanning element 312 and the second scanning element 314, the sample OCT light L o The sample OCT light L is directed to any position within the field of view of the FD-OCT device 100 on a subarea of ​​the retina of the eye 160. As described above, the rotation of the first scanning element 312 and the second scanning element 314 is coordinated by the controller 140 or by a dedicated scanning system controller (not shown) so that the sample OCT light L o A predefined scanning pattern is scanned on a subarea of ​​the retina of the eye 160. The predefined scanning pattern may be any suitable scanning pattern known to those skilled in the art, such as unidirectional scanning (wherein a set of parallel scanning lines are along a common direction, the scanning lines extending along the common direction), circular scanning, serpentine scanning or spiral scanning, which may be existing or selected by the user of the FD-OCT device 100 during manufacturing.

[0084] As in the present exemplary embodiment, the first curved mirror 313 and the second curved mirror 315 may be respective ellipsoidal mirrors each having a first focus and a conjugate second focus. The first scanning element 312 is located at the first focus F of the first curved mirror 313. P1 and the second scanning element 314 is located at the second focus F of the first curved mirror 313 P2The second scanning element 314 is also located at the first focus F of the second curved mirror 315. P3 and the eye 160 is located at the second focus F of the second curved mirror 315 P4 More specifically, the pupil of the eye 160 is located at the second focus F of the second curved mirror 315. P4 , so that the optical path of the scanning system 310 can be turned in two dimensions on a partition of the retina of the eye 160. However, the first curved mirror 313 and the second curved mirror 315 can be any reflective component with an aspherical reflective surface, such as a shape similar to a parabola or hyperbola of a conical section, or more generally can have a shape described by one or more polynomial functions of two variables.

[0085] As described in further detail in WO 2014 / 53824A1, the use of curved mirrors in the scanning system 310 allows the FD-OCT imaging system 130 to be used as a widefield FD-OCT imaging system or an ultra-widefield (UWF) FD-OCT imaging system, the contents of which are hereby incorporated by reference in their entirety. However, the scanning system 310 is not limited thereto.

[0086] Figure 3B is a schematic diagram of an alternative implementation of an example optical system 330 and an example FD-OCT imaging system 331 that share a lens-based scanning system 332 (where the same reference numerals indicate the same Figure 3A ). Figure 3B As shown, instead of being guided by curved mirrors 313 and 315, light is guided from the first scanning element 312 to the second scanning element 314, and then is guided through a lens relay (barrel) 334 via a beam splitter 333 to the retina of the eye 160, which lens relay includes one or more lenses. The beam splitter 333 can take a similar form to the beam splitter 311 (for example, it can be a beam splitter cube or a dichroic mirror). In addition, the scanning system 332 can include a first lens relay and a second lens relay (which can retain equal focal lengths) between the first scanning element 312 and the second scanning element 314 (as the only intervening intermediate optical devices). The fixation target 335 can be provided as Figure 1 1. An example of a fixation target 110. Light from a fixation target 335 may pass through a beam splitter 333, a lens relay 334 and then reach the eye 160.

[0087] As in the present example embodiment, first scanning element 312 and second scanning element 314 may each be a galvanometer optical scanner (“H-galvanometer” and “V-galvanometer”, respectively). However, another type of scanning element, such as a MEMS scanning mirror or a resonant scanning mirror, for example, may be used instead.

[0088] The detector 323 is arranged to detect the interference light L I That is, the detector 323 is arranged to receive the interference light L from the interferometer 322 I And based on the received interference light L I Generate detection signal S d The detector 323 performs a detection on the interference light L incident on the photoelectric element of the detector 323. I The photoelectric conversion generates a detection signal S d . The specific form of the detector 323 depends on the implementation form of the FD-OCT imaging system 320. For example, in the case where the FD-OCT imaging system 320 is implemented as an SD-OCT imaging system, the detector 323 includes a spectrometer, which may have a diffraction grating, a Fourier transform lens, and a detector array (or a line scan camera). In the case where the FD-OCT imaging system 320 is implemented as an SS-OCT imaging system, the light detector 120 may include a balanced photodetector device, which includes two photodetectors (e.g., reverse-biased photodiodes), and the output photocurrents of the two photodetectors are subtracted from each other, wherein the subtracted current signal is converted into a voltage detection signal through a transimpedance amplifier. As in the present example embodiment, the detection signal S d The OCT data processing hardware of the FD-OCT imaging system 320 may then be processed to generate the OCT data 135. However, the functions of the OCT data processing hardware may alternatively be performed by the controller 140 (ie, the detection signal S d may be received and processed by controller 140 to generate OCT data 135 ).

[0089] Reference again Figure 3A , where the FD-OCT imaging system 320 is a line scanning system rather than a point scanning system, as described above, the OCT light source 321 generates light. In this case, the interferometer 322 is instead arranged to transmit the light rather than the OCT beam L b The scanning system 310 is arranged to perform a line scan of the sample OCT light on a sub-area of ​​the retina of the eye 160 and collect light L that has been scattered by the sub-area of ​​the retina of the eye 160 during the line scan. c Therefore, the scanning system 310 may further include a lens arranged to focus the sample OCT light at a first focus F of the first curved mirror 313. P1The sample OCT light is then reflected by the first scanning element 312, the first curved mirror 313, the second scanning element 314, and the second curved mirror 315 in sequence before being incident on a subdivision of the retina of the eye 160, and the light scattered from the subdivision of the retina of the eye 160 travels back to the detector 323 (i.e., a detector adapted for a line scanning system) via the scanning system 310 in the same manner as described above for the point scanning implementation. Thus, the sample OCT light can be steered in two dimensions within the eye by rotating the first scanning element 312 and the second scanning element 314, so that scanning of the eye 160 can be performed by the scanning system 310, such as coordinated by the controller 140 or a dedicated scanning system controller. However, when the sample OCT light is incident on a subdivision of the retina, the scanning system 310 thereby acquires at least one B-scan (e.g., a series of B-scans forming a C-scan) of the retina of the eye 160, rather than acquiring at least one A-scan as in the point scanning implementation.

[0090] The light source 301 of the optical system 300 is arranged to generate light L s As an optical stimulus. In this example embodiment, the light L s The light may have one or more wavelengths in the visible spectrum of the human eye, although more generally the light may have any wavelength for stimulating a physiological response of the retina of the eye 160. The light source 301 may be arranged to generate a plurality of lights of different wavelengths, each of which may be used as an optical stimulus as desired (e.g., by using a broadband spectral source, which may produce white light, filtered by at least one tunable or removable spectral filter), but this may alternatively be achieved by including an additional light source in the optical system 300, which is arranged to generate light L having wavelengths which are different from the light L. s The wavelength of light is different from that of light L s It can be an optical stimulus (these light sources can be combined into a single output of light source 301 using fiber couplers, wavelength division multiplexed (WDM) fibers, beam splitters or dichroic mirrors).

[0091] In addition, the light source 301 can be controlled by the controller 140 to generate light L of a desired light intensity. s .

[0092] As in the present example embodiment, the light source 301 may include an illumination source (e.g., a light emitting diode) and an illumination source aperture in a manner similar to the above-described OCT light source 321. For example, the light source 301 may include additional components, such as one or more collimating lenses for collimating light from the light source. As described below, the controller 140 controls the light source 301 of the optical system 300 to generate light L s As an optical stimulus, the light source 301 may be further controlled to change the duration of the optical stimulus provided by the light source 301 .

[0093] As in the present example embodiment, the beam splitter 311 may be a cubic beam splitter. However, it may alternatively be a dichroic mirror, for example.

[0094] The optical system 300 shares the scanning system 310 used by the FD-OCT imaging system 320 to perform point scanning. This is done by coupling the light L using a beam splitter 311. s The optical path followed by the sample OCT light L o This is achieved by traveling through the optical path followed by the scanning system 310, but any other suitable arrangement for coupling two optical paths may be used. s The optical path followed by the sample OCT light L generated by the light source 301 as it travels through the scanning system 310 can be coupled to o The optical paths followed by travel through scanning system 310 and beam splitter 311 are such that the optical paths extend along a common axis, but the optical paths may alternatively extend along axes offset by a predetermined amount (e.g., by adjusting the incident position of one of the optical paths on beam splitter 311).

[0095] Therefore, the scanning system 310 is also arranged to convert the light L s The light L is guided to the retina of the eye 160. s The light enters the scanning system 310 through the beam splitter 311 , is then reflected by the first scanning element 312 , the first curved mirror 313 , the second scanning element 314 , and the second curved mirror 315 in sequence, and is then applied to the retina of the eye 160 .

[0096] With the sample OCT light L o In the same manner, the optical system 300 can be controlled to change the light L to be applied to the retina of the eye 160 in the following manner: s The first scanning element 312 is rotated about a first axis (not shown) to move the optical path of the scanning system 310 in a first direction or in a direction opposite to the first direction on the retina of the eye 160, and the second scanning element 314 is rotated about a second axis 316 to move the optical path of the scanning system 310 in a second direction or in a direction opposite to the second direction on the retina of the eye 160. By rotating the first scanning element 312 and the second scanning element 314, the optical path of the scanning system 310 can be moved in two dimensions. s The optical path followed by the light L s can be applied to any location on the retina of the eye 160. Therefore, by controlling the light L generated by the light source 301 sBy adjusting the timing and duration of the scanning element 312 and / or the second scanning element 314, and the rotation range and speed, the controller 140 can make any position on the retina of the eye 160 be illuminated by the light L s The stimulation lasts for a desired duration. The duration can be controlled by the controller 140 and the light L generated by the light source 301. s The intensity of the bleaching agent is controlled to obtain a predetermined degree of bleaching of the retina of the eye 160. For example, the degree of bleaching obtained may be between 10% and 66%. For studying alpha waves in the ORG data 150 (i.e., fast retinal responses), higher bleaching values ​​may be preferred.

[0097] By sharing the scanning system 310 between the optical system 300 and the FD-OCT imaging system 320, the optical system 300 can access the full field of view of the FD-OCT imaging system 320 without any additional scanning hardware. As described above, for example, in the case where the FD-OCT imaging system 320 is a UWF FD-OCT imaging system, this reduces the complexity of the FD-OCT apparatus 100 and can allow the optical system 300 to be more easily integrated into a complex sample arm.

[0098] Figure 3C is a schematic diagram of an optical system 340 and an FD-OCT imaging system 341. According to an alternative implementation of this example embodiment, the optical system 340 and the FD-OCT imaging system 341 may form Figure 1 Example implementation of the optical system 120 and the FD-OCT imaging system 130 (wherein the same reference numerals indicate the same Figure 3A The optical system 340 and the FD-OCT imaging system 341 are respectively Figure 3A The optical system 300 is the same as the FD-OCT imaging system 320, but the difference is Figure 3A These components in FIG. 3 share scanning system 342 instead of scanning system 310. Scanning system 342 is identical to scanning system 310 except that it includes third scanning element 343 and beam splitter 344. Third scanning element 343 may be implemented in the same form as first scanning element 312, but is used by scanning system 342 (instead of first scanning element 312) to convert light L from light source 301 into a beam splitter. s The light L to be applied to the retina of the eye 160 is guided to the retina of the eye 160, and changes the light L to be applied to the retina of the eye 160 in a first direction and in a direction opposite to the first direction. s The beam splitter 344 may be implemented in the same form as the beam splitter 311 and is positioned to split the light L from the light source 301 s Guided to the first curved mirror 313, and the sample OCT scan L oThe light L is guided to the first curved mirror 313 (and the collected light L c to the first scanning element 312). Although not shown in Figure 3C The fixation target is shown in FIG. 3 , but the fixation target may be located in the scanning system 342, on at least one side of the first curved mirror 313, or in the Figure 3C , as described in US 11,253,146 B2. Thus, light from such a fixation target can be passed via the second scanning element 314 and then via the second curved mirror 315 to reach the eye 160.

[0099] Since it is used by the scanning system 342 to s The third scanning element 343 directed to the retina of the eye 160 is different from the first scanning element 312, so it can be independently controlled by the controller 140. s The optical path followed by the sample OCT light L generated by the light source 301 as it travels through the scanning system 342 can vary in a first direction (or in a direction opposite to the first direction) and can be different from the sample OCT light L generated by the light source 301 as it travels through the scanning system 342. o The optical path followed by the light L through the scanning system 342 is irrelevant. s The optical path followed by the scanning system 342 is coupled to the sample OCT light L in only one dimension. o The optical path followed by the scanning system 342 is similar to Figure 3A and Figure 3B This adds an additional degree of freedom to the variation of the optical stimulus on the retina of the eye 160, although at the expense of increased complexity of the FD-OCT apparatus 100. For example, by removing the light L s Optical path and sample OCT beam L o This degree of freedom may be advantageous for studying photoreceptor pathways within the retina by removing at least some coupling between the centers of the first subdivision and the second subdivision of the retina (e.g., introducing a spatial offset between the center of the first subdivision and the center of the second subdivision of the retina).

[0100] although Figure 3C The exemplary embodiment includes curved mirrors 313 and 315, but as Figure 3D These can be omitted as shown, Figure 3D is a schematic diagram of an example optical system 350 and an example FD-OCT imaging system 351 that share a scanning system 352 with curved mirrors 313 and 315 omitted (whereby the same reference numerals indicate the same FIG. 3A to FIG. 3C ). Figure 3DAs shown, light is directed from the first scanning element 312 and from the third scanning element 343 to the second scanning element 314 via the first lens relay 353 and the second lens relay 354 (which may have equal focal lengths) located between the third scanning element 343 and the second scanning element 314. The first lens relay 353 and the second lens relay 354 are optional, and in an alternative example embodiment, the only intervening optical device between the first scanning element 312 and the second scanning element 314 and between the third scanning element 343 and the second scanning element 314 may be a beam splitter 344. Figure 3D As shown, it can be Figure 3B The scanning system 332 is similarly configured in the Figure 3D A fixation target 335 is provided in the scanning system 352.

[0101] Figure 3E 3 is a schematic diagram of an optical system 360 and an FD-OCT imaging system 361 constituting an additional alternative implementation of the optical system 120 and the FD-OCT imaging system 130 of the example embodiment. The optical system 360 is different from Figure 3A The optical system 300 and the FD-OCT imaging system 361 are different from Figure 3A The FD-OCT imaging system 320 is different only in that it shares a scanning system 362 (instead of the scanning system 310). The scanning system 362 is similar to Figure 3B The scanning system 332 includes, for example, one or more lenses in a lens relay (lens barrel) 334 instead of Figure 3A The curved mirrors 313 and 315 of the scanning system 332 are different from the scanning system 332 in that the scanning system 332 further includes a third scanning element 363, a fourth scanning element 364 and a beam splitter 365 instead of Figure 3B The third scanning element 363 can be implemented in the same form as the first scanning element 312, and the fourth scanning element 364 can be implemented in the same form as the second scanning element 314, although the third scanning element 363 and the fourth scanning element 364 are used by the scanning system 362 (instead of the first scanning element 312 and the second scanning element 314) to convert the light L s The light L to be applied to the retina of the eye 160 is guided to the retina of the eye 160 and changes the light L to be applied to the retina of the eye 160 in a first direction, a direction opposite to the first direction, a second direction, and a direction opposite to the second direction. sThe scanning system 362 may also include a first relay lens and a second relay lens (not shown) between the first scanning element 312 and the second scanning element 314, and may include a third relay lens and a fourth relay lens (not shown) between the third scanning element 363 and the fourth scanning element 364. The beam splitter 365 may be implemented in the same form as the beam splitter 333, and may be arranged to direct light from the fourth scanning element 364 through the lens barrel 334 toward the eye 160.

[0102] Scanning system 362 may also include Figure 3B The beam splitter 366 and fixation target 335. Light from the fixation target 335 can be guided by the beam splitter 366 through the beam splitter 365, the lens relay 334, and then to the eye 160.

[0103] Used by scanning system 362 to convert light L s The third scanning element 363 and the fourth scanning element 364 directed to the retina of the eye 160 are different from the first scanning element 312 and the second scanning element 314 used by the scanning system 362 to direct the sample OCT light L o The light L is directed to the retina, and the scanning elements 363 and 364 can be controlled by the controller 140 independently of the scanning elements 312 and 314. s The optical path followed by the sample OCT light L as it travels through the scanning system 362 when generated by the light source 301 may vary in a first direction (or in a direction opposite to the first direction) and in a second direction (or in a direction opposite to the second direction) with respect to the sample OCT light L. o The optical path followed by the light L through the scanning system 362 is irrelevant. s The optical path followed by the scanning system 362 is not coupled to the sample OCT light L o The optical path followed by the scanning system 362 allows independent control of the changes in the optical stimulus on the retina of the eye 160 in two degrees of freedom, although unlike the above reference Figures 3A to 3D The trade-off is increased complexity of the FD-OCT apparatus 100 compared to the described implementation.

[0104] Although the scanning system 362 includes the third scanning element 363 and the fourth scanning element 364, these may alternatively be replaced by a single two-dimensional scanner (eg, a micro-electromechanical system (MEMS) scanner).

[0105] Figure 3F 3 is a schematic diagram of an example optical system 370 and an example FD-OCT imaging system 371 that share a scanning system 372 including a two-dimensional scanner 373. Figure 3FIn, with FIG. 3A to FIG. 3E The same elements are labeled with the same numbers. The scanning system 372 is the same as the scanning system 362 except that it includes a two-dimensional scanner 373 (instead of the third scanning element 363 and the fourth scanning element 364), which is used to convert the light L s The light L to be applied on the retina of the eye 160 is guided to the retina of the eye 160, and changes the light L to be applied on the retina of the eye 160 in a first direction, a direction opposite to the first direction, a second direction, and a direction opposite to the second direction. s location.

[0106] Scanning system 372 may also include Figure 3B The beam splitter 366 and fixation target 335. Light from the fixation target 335 can be guided by the beam splitter 366 through the beam splitter 365, the lens relay 334, and then to the eye 160.

[0107] As another alternative implementation of the exemplary embodiment, the optical system 120 may include a spatial light modulator that can be controlled by the controller 140 to change the light L to be applied on the retina. s For example, the spatial light modulator may include a projector having a light source 301, a collimator, and a dynamic amplitude mask (e.g., in the form of a digital micromirror device (DMD)) arranged to be illuminated by collimated light and controllable by the controller 140 to allow the collimated light L generated by the light source 301 to be s Only a predefined portion of the dynamic amplitude mask is passed, thereby changing the position at which the light from the light source 301 is incident on the retina.

[0108] Where the dynamic amplitude mask is provided in the form of a DMD, the DMD may include an array of rotatable micromirrors that may be individually controlled by the controller 140 to switch from one of the first and second orientations to the other of the first and second orientations. More specifically, the DMD may be configured to set each micromirror in the DMD to a first orientation to reflect light from the light source 301 toward the eye 160, or to a second orientation to reflect incident light away from the eye 160, thereby preventing light from the light source 301 from reaching the eye 160. In this manner, the use of the DMD allows for binary amplitude modulation of light received at each micromirror position on the DMD.

[0109] However, it should be noted that the functionality of the dynamic amplitude mask may be provided by any suitable type of spatial light modulator other than a DMD, such as an array of liquid crystal cells or an analog micromirror array. For example, in an alternative example embodiment where the dynamic amplitude mask comprises an array of liquid crystal cells, the liquid crystal in each liquid crystal cell of the array may be individually switched between a first liquid crystal phase and a second liquid crystal phase. The liquid crystal cell in the first liquid crystal phase switches the light L incident thereon to the first liquid crystal phase. s On the other hand, the liquid crystal cell in the second liquid crystal phase blocks the incident light L s , preventing it from being transmitted to the eye 160. In addition, the unmasked portions of the dynamic amplitude mask can be composed of liquid crystal cells in the array having liquid crystal in a first phase, while the masked portions of the dynamic amplitude mask can include liquid crystal cells in the array having liquid crystal in a second phase. As another example, the spatial light modulator can include an array of light sources (e.g., LEDs) that are arranged to provide corresponding collimated, spatially separated light beams and can be controlled by the controller 140 to provide control over the location on the retina where the optical stimulus is applied.

[0110] In addition, for example, when the FD-OCT imaging system 130 is a full-field FD-OCT imaging system, a spatial light modulator may be used to change the light L to be applied on the retina of the eye 160. s location.

[0111] It should be noted that although the above arrangement for varying the location on the retina where the optical stimulus is to be applied is described in the context of the FD-OCT imaging system 130, the FD-OCT imaging system 130 is arranged to direct the single sample OCT beam L o Delivered to the retina of eye 160, but the present disclosure is not limited to this, and these arrangements for changing the location on the retina where the optical stimulus is to be applied may also be used within a multi-beam FD-OCT imaging system arranged to simultaneously deliver multiple sample OCT beams to the retina.

[0112] The above arrangement can allow the location on the retina where the optical stimulus is applied to be set with greater accuracy than if the location on the retina where the optical stimulus is applied is set by turning the eye, for example, by moving the fixation target 110 laterally relative to the eye 160 (i.e., moving it in the field of view of the eye 160) to change the location on the retina where the optical stimulus is applied. In addition, keeping the fixation target 110 in a fixed position during acquisition of the ORG data 150 can improve patient comfort and improve the ease of use of the system. In addition, some of the above arrangements for changing the location on the retina where the optical stimulus is to be applied utilize existing optics of an OCT sample arm, thereby making it easier to integrate the optical system 120 into an existing OCT system.

[0113] Return to Figure 1, the controller 140 is arranged to acquire at least one indicator 141 of a target location on the retina to which an optical stimulus is to be applied by the optical system 120, and to control the optical system 120 using the acquired indicator 141 while the position of the fixation target 110 relative to the eye 160 remains fixed to apply the optical stimulus to a first subdivision of the retina at the target location. The controller 140 is also arranged to control the FD-OCT imaging system 130 to acquire OCT data 135 of a second subdivision of the retina, wherein at least a portion of the second subdivision of the retina is arranged relative to the first subdivision so as to be stimulated by the applied optical stimulus during acquisition of at least some of the OCT data 135. As described in more detail below, the controller 140 is also arranged to generate ORG data 150 based on the acquired OCT data 135.

[0114] Controller 140 (and dedicated scanning system controller, if provided) may be provided in any suitable form, such as as Figure 4 The programmable signal processing hardware 400 of the type schematically shown in FIG. The programmable signal processing device 400 includes a communication interface (I / F) 410 for receiving OCT data 135 (or detection signal S) from the FD-OCT imaging system 130. d), and in some cases receives indicator 141, outputs control signals to FD-OCT imaging system 130 and outputs ORG data 150 and / or a graphical representation thereof to a map display device 142 (such as a computer screen, etc.) for display thereby. Signal processing hardware 400 also includes a processor 420 (e.g., a central processing unit CPU and / or a graphics processing unit GPU), a working memory 430 (e.g., a random access memory), and an instruction storage device 440 storing a computer program 445, which includes computer readable instructions that, when executed by processor 420, cause processor 420 to perform various functions, including those of controller 140 described herein. Working memory 430 stores information used by processor 420 during execution of computer program 445. Instruction storage device 440 may include a ROM (e.g., in the form of an electrically erasable programmable read-only memory (EEPROM) or flash memory) preloaded with computer readable instructions. Alternatively, the instruction storage device 440 may include RAM or a similar type of memory, and the computer-readable instructions of the computer program 445 may be input to the instruction storage device 440 from a computer program product (e.g., a non-transitory computer-readable storage medium 450 in the form of a CD-ROM, DVDROM, etc.) or a computer-readable signal 460 carrying the computer-readable instructions. In any case, the computer program 445, when executed by the processor 420, causes the processor 420 to perform the functions of the controller 140 described herein. In other words, the controller 140 of the example embodiment may include a computer processor 420 and a memory 440 storing computer-readable instructions, as described herein, which when executed by the computer processor 420 causes the computer processor 420 to acquire an indicator 141 of a target location on the retina to which an optical stimulus will be applied by the optical system 120, and to control the optical system 120 using the acquired indicator 141 while the position of the fixation target 110 relative to the eye 160 remains fixed to apply the optical stimulus to a first subdivision of the retina located at the target location, control the FD-OCT imaging system 130 to acquire OCT data 135 of a second subdivision of the retina, wherein at least a portion of the second subdivision of the retina is disposed relative to the first subdivision so as to be stimulated by the applied optical stimulus during acquisition of at least some of the OCT data 135, and generate ORG data 150 based on the acquired OCT data 135.

[0115] However, it should be noted that the controller 140 may alternatively be implemented in non-programmable hardware (such as an ASIC, FPGA, or other integrated circuit dedicated to performing the functions of the controller 140 described above), or as described above with reference to Figure 4In addition, although the controller 140 is described with respect to a single programmable signal processing hardware 400, the controller 140 is not limited thereto, and the functions of the controller 140 may be implemented in a combination of non-programmable hardware and programmable hardware. Figure 4 The controller 140 may be divided between a plurality of programmable signal processing hardware of the type shown or portions thereof and / or the aforementioned non-programmable hardware. Figure 4 The FD-OCT imaging system 130 may be implemented by programmable signal processing hardware of the type shown in the figure, as described herein, arranged to acquire an indicator 141 of a target location on the retina to which an optical stimulus is to be applied by the optical system 120, use the acquired indicator to control the optical system 120 to apply the optical stimulus to a first subdivision of the retina at the target location while the position of the fixation target 110 relative to the eye 160 remains fixed, and control the FD-OCT imaging system 130 to acquire OCT data 135 of a second subdivision of the retina, wherein at least a portion of the second subdivision of the retina is disposed relative to the first subdivision so as to be stimulated by the applied optical stimulus during acquisition of at least some of the OCT data 135. In this case, as described herein, a separate processor (e.g., similar to Figure 4 The processor 420 in the controller 140 may be arranged to receive the acquired OCT data 135 from the controller 140 and generate ORG data 150 based on the acquired OCT data 135 (and output the ORG data 150 to, for example, the image display device 142).

[0116] As in the present example embodiment, the map display device 142 may be arranged to receive data for display to a user (e.g., a clinician), for example, from the controller 140, and the communication interface 410 may be arranged to receive input from a user of the FD-OCT apparatus 100, such as input required by the controller 140. For example, the map display device 142 may receive and display the ORG data 150 or a graphical representation thereof, or may be controlled by the controller 140 to display a map as described below. The input from the user of the FD-OCT apparatus 100 may include, for example, an indicator 141, or an indication of a second subregion of the retina as will be described later, which the map display device 142 may transmit to the controller 140. The map display device 142 may be, for example, an LCD screen, and may include Figure 4140 , which may be used to generate a graphical representation of the ORG data 150, process input provided by a user (e.g., by processing touch input from a user where the graphic display device 142 is a touch screen) and interface with the controller 140. However, the graphic display device 142 is optional and may be omitted. For example, the aforementioned functions of the graphic display device 142 may be provided by an external computer, or in some cases, it may not be necessary to display the ORG data 150, and the ORG data may instead be stored on an external server or in a memory of the controller 140 for later retrieval.

[0117] Figure 5 1 is a flow chart illustrating a process by which the controller 140 may generate the ORG data 150 in this example embodiment. The process defines an ORG capture session that may be initiated by a dark adaptation period of the retina of the eye 160. For example, the FD-OCT device 100 may be arranged to prevent light (both internal and external to the FD-OCT device 100) from being incident on the retina of the eye 160 for a predetermined duration (e.g., approximately 5 minutes), or the patient may be more simply instructed to close their eyes or wait in a dark room for the predetermined duration.

[0118] exist Figure 5 In process S51, the controller 140 obtains an indicator 141 of a target position on the retina of the eye 160 to which the optical stimulus is to be applied by the optical system 120. For example, the indicator 141 may indicate the position of a point on the retina of the eye 160 at which the center of the optical stimulus applied by the optical system 120 is located. The indicator 141 of the target position may be automatically generated based on a predetermined position on the retina defined relative to one or more anatomical landmarks (e.g., optic disc, macula, etc.) and taking into account the gaze direction 161 of the eye 160. Alternatively, the indicator 141 of the target position may be input to the controller 140 by, for example, a user selecting the target position on a retinal image (e.g., an en-face OCT image previously acquired by the FD-OCT imaging system 130 or a reflectance image of the retina previously acquired using a scanning laser ophthalmoscope (SLO), e.g., a scanning laser ophthalmoscope may be included in the FD-OCT imaging apparatus 100 and share a scanning system 310 with the FD-OCT imaging system 130) displayed on the image display device 142 (or an external display, such as a computer screen, etc.) using a mouse and / or keyboard or via one or more touch interactions if the display is a touch screen.

[0119] exist Figure 5In process S52 of the embodiment, while the position of the fixation target 110 relative to the eye 160 remains fixed and the eye 160 is fixated on the fixation target 110 (i.e., while the position of the fixation target in the field of view (FoV) of the eye 160 remains fixed, wherein the FoV covers everything that the eye 160 can see when pivoting in its eye socket when the head is held in a fixed orientation), the controller 140 uses the acquired indicator 141 to control the optical system 120 to apply optical stimulation to a first sub-area of ​​the retina of the eye 160 at the target position. The controller 140 may use the acquired indicator 141 to control the optical system 120 to change the position on the retina where the optical stimulation is to be applied to the target position while the position of the fixation target 110 relative to the eye 160 remains fixed, and to apply the optical stimulation to the first sub-area of ​​the retina at the target position. The controller 140 may be configured to transform the location on the retina indicated by the indicator 141 into a corresponding set of one or more control parameters for steering the optical system 120 to apply the optical stimulus at a location on the retina substantially the same as the location indicated by the indicator 141. This may be accomplished in one of a number of different ways. For example, the controller 140 may use a mapping between locations on the retina and values ​​of corresponding control parameters, which may be provided, for example, in the form of a lookup table (LUT) or a function defined by a set of parameters. The mapping may be determined by calibration using techniques known to those skilled in the art.

[0120] In this example embodiment, Figure 3A As shown, the controller 140 controls the scanning system 310 to rotate the first scanning element 312 and the second scanning element 314 so that the light L s The light L is incident on the target position by traveling through the optical path followed by the scanning system 310, and the controller 140 controls the light source 301 to generate light L s , so as to propagate along the optical path after or, as the case may be, during the above-mentioned rotation. As in the present example embodiment, the first subdivision of the retina can be smaller than the field of view of the FD-OCT imaging system 130 (e.g., less than 0.1%, 1%, or 10% of the area covered by the field of view of the FD-OCT imaging system 130). Examples of the first subdivision of the retina are shown and described in more detail below.

[0121] exist Figure 5In process S53, the controller 140 controls the FD-OCT imaging system 130 to acquire OCT data 135 of a second partition of the retina of the eye 160. The controller 140 may acquire a second indicator indicating the location of the second partition of the retina of the eye 160 by the user selecting the location of the second partition of the retina on the map display device 142 in a scanner similar to that described in process S51 for the indicator 141. Alternatively, the second indicator may be generated by the controller 140 based on at least one of the indicator 141 or the first partition of the retina of the eye 160, as described in more detail below. For example, the second partition may have a predetermined, fixed positional relationship with the first partition.

[0122] As in the present example embodiment, the acquisition of OCT data 135 may be a time series of OCT images of a second subarea of ​​the retina of the eye 160 within a first time period (i.e., a time period between the acquisition time of a first OCT image in the time series of OCT images and the acquisition time of a last OCT image in the time series of OCT images). Figure 3A In the illustrated example embodiment, the controller 140 controls the rotation of one or both of the first scanning element 312 and the second scanning element 314 to perform point scanning of a second subarea of ​​the retina of the eye 160 according to a predetermined scanning pattern to acquire a temporal sequence of OCT images. The controller 140 may alternatively instruct a dedicated scanning system controller (where provided) to control one or both of the scanning elements 312 and 314.

[0123] At least a portion of a second subdivision of the retina of the eye 160 is positioned relative to the first subdivision so as to be stimulated (or at least partially illuminated) by the applied optical stimulus during the acquisition of at least some of the OCT data 135. That is, during the execution of process S53 for the second subdivision of the retina, the controller 140 previously executed process S52 and used the acquired indicator 141 to control the optical system 120 to apply the optical stimulus to the corresponding first subdivision of the retina of the eye 160 at a first time falling within the first time period, so that at least some OCT images in the time sequence of OCT images are acquired after the first time, and in each of these OCT images at least a portion of the second subdivision of the retina of the eye 160 is stimulated (or at least partially illuminated) by the applied optical stimulus. The second subdivision of the retina may at least partially overlap with the corresponding first subdivision of the retina, or it may alternatively be disposed away from but sufficiently close to the corresponding first subdivision so that light incident on the first subdivision is scattered into at least some of the second subdivision, or otherwise provide at least a portion of the second subdivision of the retina with optical stimulus for stimulating the retinal area therein. Examples of the location of a second subdivision of the retina of eye 160 relative to a corresponding first subdivision of the retina of eye 160 are described in more detail below.

[0124] In a variation of the example embodiment, as described above, the controller 140 may first obtain an indication of the location of the second subdivision of the retina at which OCT data 135 is to be acquired, and may subsequently generate the indicator 141 so that the first subdivision of the retina at the target location stimulates at least a portion of the second subdivision of the retina (i.e., so that ORG data 150 may be generated at the location of the second subdivision of the retina). For example, the location of the first subdivision may be selected to be along a predetermined scanning pattern for acquiring OCT data 135. Thus, for example, Figure 3A or Figure 3B One or both of the first scanning element 312 and the second scanning element 314 in Figure 3C or Figure 3D The same rotation of the second scanning element 314 in process S52 can be used to acquire OCT data 135 and apply optical stimulation to the first subregion of the retina. This can allow optical stimulation to be applied to the eye 160 within a smaller time window than would be possible if the controller 140 needed to coordinate different rotations of the scanning elements in processes S52 and S53, which may be important when the time series of OCT images acquired in process S53 are closely spaced in time (e.g., this may be desirable to reduce motion artifacts in the OCT images). Note that the position of the first subregion is not along a predetermined scanning pattern on the retina, but is instead determined by using a predetermined scanning pattern as described above with reference to FIG. FIG. 3C to FIG. 3FThe advantages can similarly be achieved (although at the expense of increased system complexity) with the arrangement described but with the scanning pattern shifted.

[0125] Reference again Figure 5 In process S54, the controller 140 generates ORG data 150 based on the acquired OCT data 135. As in the present exemplary embodiment, the controller 140 may generate the ORG data 150 based on the phase information in the acquired OCT data 135. For example, the ORG data 150 generated by the controller 140 may be displayed to a user on the image display device 142, or output to an external computer or server for analysis.

[0126] The controller 140 can generate ORG data 150 based on the acquired OCT data 135 using any technique known to those skilled in the art, such as the velocity-based ORG technique described in Kari V. Vienola et al. (published in 2022), "Velocity-based optoretinography for clinical applications," Optica 9, 1100-1108, which is incorporated herein by reference in its entirety. In short, this velocity-based ORG technique generates ORG data based on the acquired OCT data (in this case, the OCT data includes a time series of B-scans) by first flattening each B-scan so that the photoreceptor inner and outer segments (IS / OS) and cone outer segment (COST) reflections are at the same height for each A-scan in each corresponding B-scan. Then, a moving (e.g., 10 ms) time window is used to select a set (e.g., five) sequential B-scans, in which motion correction is performed relative to the first B-scan in the series. The phase data cube of each composite data cube for each spatial coordinate pair in the volume is then expanded in the time dimension to minimize the amplitude of the phase difference between the data cubes of consecutive phase B scans. After expansion, the phase change rate is calculated for each coordinate pair by using a least squares linear fit with respect to time to calculate the instantaneous velocity for each spatial position. If necessary, these instantaneous velocities and B-scan amplitudes are averaged in the lateral dimension to give instantaneous depth-related metrics for velocity and backscattering, respectively. By moving (10ms) time windows, a time series of depth profiles is constructed for velocity and reflectivity, respectively. Both of these can be visualized as M scans in time-depth coordinates. The velocities of the IS / OS and COST layers are then extracted, and the difference between them is the rate of contraction / elongation of the OS in the region over time, which can form ORG data 150 (or, alternatively, the OS length response can be ORG data 150). However, these techniques can be applied to other retinal layers, such as rod photoreceptors, by extracting the velocities of the IS / OS and ROST layers. Alternatively, the amplitude of so-called "alpha waves" (i.e., fast retinal responses, typically on a time scale of a few milliseconds) in the contraction / elongation rate data of the outer segment (OS) over time may be determined and saved as (or as part of) the ORG data 150. Additionally or alternatively, the amplitude of so-called "beta waves" (i.e., slow responses, typically on a time scale of a few seconds) may be determined and saved as (or as part of) the ORG data 150.As another alternative, the ORG data 150 may include a value indicating the quality of a retinal response at a location of the second subdivision of the retina (e.g., on a predefined scale, such as a scale of 1 to 10), the value being generated by comparing the retinal response indicated by the acquired ORG data to the response of a healthy retina. For example, the healthy retinal response may be obtained from ORG data at a location on the retina of an eye 160 that is assessed by a clinician to be healthy, or may be obtained from ORG data of a sample healthy eye.

[0127] The controller 140 can generate ORG data 150 based on the acquired OCT data 135 using an intensity-based ORG technique, such as the OCT brightness variation and OCT band analysis technique described in Kim T-H, Ma G, Son T, and Yao X (published in 2022), "Functional Optical Coherence Tomography for Intrinsic Signal Optoretinography: Recent Developments and Deployment Challenges", Front. Med. 9: 864824, the contents of which are incorporated herein by reference in their entirety. The OCT brightness variation technique can be used to detect local changes in pixel intensity values ​​caused by light stimulation on the retina. Data processing techniques used in OCT brightness change analysis techniques may include registering raw OCT B-scans to account for eye movement, normalizing pixel intensity based on inner retinal intensity to limit the effects of pupillary response, identifying "active" intrinsic optical signal (IOS) pixels (i.e., pixels that exhibit significant intensity changes after light stimulation, which may be positive with increased intensity and negative with decreased intensity), and quantifying the number of these active IOS pixels for analysis. OCT band analysis techniques may include, for example, deconvolution methods for band analysis (e.g., of high and low reflective bands in the retina). In the case of using intensity-based ORG techniques, the OCT data may be acquired by an OCT imaging system that is not phase-stabilized.

[0128] Fig. 6A , Figure 6B and Figure 6C1 is a schematic diagram of an example first subarea of ​​the retina of the eye 160 and an example corresponding second subarea of ​​the retina of the eye 160, which are illuminated by the optical system 300 according to an example embodiment and imaged by the FD-OCT imaging system 320 in the above-mentioned processes S52 and S53. These figures show a region 600 of the retina of the eye 160, which corresponds to the field of view of the FD-OCT imaging system 130. That is, the second subarea of ​​the eye 160 (for which OCT data 135 is acquired) may be located within the region 600, and the scanning system 300 may be able to transmit the sample OCT light L o Since the optical system 300 and the FD-OCT imaging system 320 share the scanning system 310, the scanning system 310 of the first subarea of ​​the eye 160 can also be located in the region 600 and can direct the light L s Guide to any position. Note that light L s can be generated by the light source 301 as a light beam, which can have different diameters, which can result in different sizes (widths) of the corresponding first subareas, such as Fig. 6A , Figure 6B and Figure 6C For example, light L s Different beam sizes (eg, diameters) can be achieved using different illumination source apertures.

[0129] In particular, in the case where the optical system 300 shares the scanning system 310 with the FD-OCT imaging system 320, the light beam (as the light L generated by the light source 301) s ) can be set so that the beam illuminates the entire second sector of the eye 160 when the beam is at each scanning position within the second sector of the eye 160. For example, where the second sector is a straight line portion corresponding to a straight B scan, the radius of the beam can be set to illuminate the entire straight line portion when the beam is at a first scanning position (the first A scan corresponding to a straight B scan) and at each subsequent scanning position. This arrangement prevents "flickering" that may be perceived by a portion of the retina due to alternating illumination and lack of illumination of the beam by the beam as the beam moves between scanning positions, which can improve the quality of the generated ORG data.

[0130] Fig. 6AA circular first partition 610 is shown as an example of a first partition of the retina in process S52, and a second partition 611 corresponding to an A-scan is shown as an example of a second partition of the retina in process S53. The controller 140 starts process S53 by controlling the FD-OCT imaging system 320 to acquire OCT data 135, which is a time series of A-scans of the second partition 611, by rotating the first scanning element 312 and the second scanning element 314 in the scanning system 310 to a first pair of corresponding angular positions so that each A-scan at the position of the second partition 611 is acquired. At the above first time, the controller 140 executes process S52, controls the optical system 300 using the acquired indicator 141 to generate light L via the light source 301. s Apply optical stimulation to the circular first subarea 610 (the diameter of the circular first subarea is the diameter of the light L incident on the retina). s Since the circular first partition 610 is concentric with the second partition 611, the first scanning element 312 and the second scanning element 314 are maintained at a first pair of corresponding angular positions during acquisition of the ORG data 150, thereby simplifying the process.

[0131] Figure 6B A hollow circular first partition 620 is shown as an example of a first partition of the retina in process S52, and Figure 5 The example of the second partition of the retina in process S53 corresponds to the second partition 621 of the circular B-scan. In this case, the controller 140 starts process S53 and controls the FD-OCT imaging system 320 to acquire OCT data 135, which is a time series of circular B-scans of the second partition 621 by rotating the first scanning element 312 and the second scanning element 314 in the scanning system 310 to perform two-dimensional point scanning using a circular scanning pattern, so that each circular B-scan has the second partition 621. At the above first time, the controller 140 executes process S52 and uses the acquired indicator 141 to control the optical system 300 to generate light L21 by the light source 301. s At the same time, the optical stimulus is applied to the hollow circular first subarea 620 (the thickness of the hollow circular first subarea 620 is the light L incident on the retina) by the first scanning element 312 and the second scanning element 314 in the rotating scanning system 310. s Since the hollow circular first partition 620 and the second partition 621 follow the same scanning pattern, the same rotation of the first scanning element 312 and the second scanning element 314 (coordinated by the controller 140) can be used to provide optical stimulation and acquire OCT data 135, which simplifies the operation of the FD-OCT device 100.

[0132] Figure 6C A straight first partition 630 is shown as an example of a first partition of the retina in process S52, and Figure 5 The example of the second subarea of ​​the retina in process S53 corresponds to the second subarea 631 of the line B scan. The controller 140 performs the same operation as described above. Figure 6B Execute in a similar manner as described in Figure 5 The process S51 to S53 (the thickness of the first linear partition 630 is the light L incident on the retina s ), except that the predetermined scanning pattern is a unidirectional scan along a single scanning axis (for a single straight line B scan). The straight line first partition 630 and the straight line second partition 631 extend along a common straight line, so that the same rotation of the first scanning element 312 and / or the second scanning element 314 (controlled by the controller 140) can be used to provide optical stimulation and acquire OCT data 135, which simplifies the operation of the FD-OCT device 100.

[0133] although Fig. 6A , Figure 6B and Figure 6C The corresponding first partitions and the corresponding second partitions in have been described as being concentric or extending along a common line, but this is not necessarily the case, and any other type of scanning pattern may be used. In addition, although the circular first partition 610, the hollow circular first partition 620, and the straight first partition 630 have been described as having a scanning pattern corresponding to the light L incident on the retina. s The corresponding diameter or thickness of the diameter, but the light L incident on the retina s The diameter of may alternatively be smaller than the expected width of the first partition, and controller 140 may coordinate the rotation of first scanning element 312 and second scanning element 314 to progressively illuminate the entirety of each first partition.

[0134] In addition, despite the Fig. 6A , Figure 6B and Figure 6C The corresponding first sub-area in FIG. 3 is shown as being larger than the corresponding second sub-area, but this is not necessarily the case. For example, the illumination source aperture of the light source 301 may be selected to provide an illumination source aperture having a diameter smaller than the sample OCT light L o Light s , or the second partition can be extended beyond the first partition of the eye 160 by the controller correspondingly controlling the rotation of one or both of the first scanning element 312 and the second scanning element 314.

[0135] Fig.6D and Fig. 6Eis a schematic diagram of an example corresponding first subarea of ​​the retina of the eye 160 within the region 600 and a corresponding example second subarea of ​​the retina of the eye 160 in the above-mentioned processes S52 and S53, the two subareas being illuminated by the optical system 360 and being illuminated by Figure 3E Imaging with the FD-OCT imaging system 361.

[0136] Fig.6D A circular first partition 640 is shown as an example of a first partition of the retina in process S52, and Figure 5 The example of the second subdivision of the retina in process S53 corresponds to the second subdivision 641 of the A scan. Fig.6D As shown, the second subarea 641 is not concentric with the circular first subarea 640, and this is achieved by independently controlling the position of the optical stimulus. FIG. 6A to FIG. 6C In contrast, the optical system 360 may be independent of the sample OCT beam L o The optical stimulus is directed to a location on the retina so that the optical stimulus can be applied to any desired portion of the retina without interrupting the acquisition of the time series of OCT images.

[0137] Fig. 6E Shown as Figure 5 The circular first partition 650 of the example of the first partition of the retina in the process S52, and as Figure 5 The example of the second partition of the retina in process S53 corresponds to the second partition 651 of the circular B scan (acquired using the circular scan as the predetermined scan pattern). These geometries can also be achieved by independently controlling the location where the optical stimulus is applied to the retina and the location where OCT data is acquired from the retina.

[0138] Fig. 6F As Figure 5 The first partition of the retina in the process S52 is an example of a straight line first partition 660 and as Figure 5 Schematic diagram of a second partition 661 of an example of a second partition of the retina in process S53, wherein the controller 140 controls the optical system 340 to provide optical stimulation and controls the FD-OCT imaging system 341 to acquire OCT data 135, the second partition 661 corresponding to a plurality of parallel straight line B scans (acquired using raster scanning as a predetermined scanning pattern) forming a C scan. In this case, the sample OCT beam L can be independently o The optical stimulation is controlled in a first direction and in a direction opposite to the first direction, the first direction being perpendicular to the line B scan. This allows the optical stimulation to be applied to the line first sub-area 660 without affecting the sample OCT beam L oThe movement in the second direction between the expected positions of each of the plurality of parallel straight line B scans. Note that similar C scans can be obtained by using the optical system 360 and the FD-OCT imaging system 361 at the expense of increased system complexity, and by interrupting the sample OCT beam L in the second direction between the expected positions of each of the plurality of parallel straight line B scans. o The optical system 300 and the FD-OCT imaging system 320 are used at the expense of movement.

[0139] Instead of acquiring a single indicator 141 for a single target location and corresponding OCT data 135 acquired for that target location, the controller 140 may alternatively acquire multiple indicators, each indicating a respective target location on the retina, and process respective OCT data of respective second subareas of the retina corresponding to respective first subareas of the retina at each target location to generate respective ORG data during an ORG capture session.

[0140] Figure 7 is a flow chart illustrating a process by which the controller 140 may acquire and process corresponding OCT data for each second subregion of the retina to generate corresponding ORG data indicating a corresponding physiological response of the second subregion of the retina to an optical stimulus applied to a corresponding first subregion of the retina. Figure 7 The process shown in FIG. 1 can be performed before the dark adaptation period of the retina of the eye 160, as described above with reference to Figure 5 The same approach described improves the accuracy and reliability of ORG data 150.

[0141] exist Figure 7 In process S71, the controller 140 acquires a plurality of indicators, each indicator indicating a corresponding target position on the retina of the eye 160 to which the optical stimulation will be applied by the optical system 120. Each of the plurality of indicators has the same form as the indicator 141 described above, and the plurality of indicators can be acquired by the controller 140 in the same manner as described for the indicator 141.

[0142] exist Figure 7 In process S72, while the position of fixation target 110 relative to eye 160 remains fixed, controller 140 uses the acquired indicator to control optical system 120 to apply optical stimulation to the corresponding independent first subarea of ​​the retina of eye 160 at each target position. Controller 140 sequentially controls the optical system 120 in the same manner as above (reference Figure 5) Each of the acquired indicators is used to control the optical system 120 in the same manner as described for indicator 141. The optical stimulus applied to each of the first subdivisions of the retina of the eye 160 does not provide stimulus in any other first subdivision of the retina of the eye 160. That is, each of the plurality of indicators has a corresponding target position on the retina that is different from the target positions indicated by the other indicators, such that each of the first subdivisions of the retina does not overlap with any other first subdivision on the retina. Each of the first subdivisions of the retina is smaller than the field of view of the FD-OCT imaging system 130 (e.g., less than 0.1%, 1%, or 10% of the area covered by the field of view of the FD-OCT imaging system 130). Examples of first subdivisions of the retina are described in more detail below.

[0143] exist Figure 7 In process S73, the controller 140 controls the FD-OCT imaging system 130 to acquire corresponding OCT data of a corresponding second subarea of ​​the retina of the eye 160 for each of the first subareas of the retina of the eye 160. The controller 140 acquires a second indicator indicating a corresponding position of the second subarea of ​​the retina on the retina, and controls the FD-OCT imaging system 130 to acquire corresponding OCT data of a corresponding second subarea of ​​the retina of the eye 160 for each of the first subareas of the retina of the eye 160. Figure 5 The corresponding OCT data of the second sub-area of ​​the retina of the eye 160 is obtained in the same manner as described in process S53 of FIG. At least a portion of each corresponding second sub-area of ​​the retina is arranged relative to its corresponding first sub-area of ​​the retina so as to be aligned with the reference Figure 5 In a similar manner as described for the first and second subdivisions of the retina, the optical stimulus applied to the first subdivision during the acquisition of at least some of the corresponding OCT data is stimulated. Each second subdivision of the retina can be separated (spaced apart) from each other second subdivision of the retina. However, in some cases, at least some of the second subdivisions can at least partially overlap at least some of the other second subdivisions. Examples of the positions of the second subdivisions of the retina relative to the corresponding first subdivisions of the retina are described in more detail below.

[0144] exist Figure 7 In the process S74, the controller 140 processes the corresponding OCT data of each second subarea of ​​the retina to generate corresponding ORG data of the second subarea, the ORG data indicating the corresponding physiological response of the second subarea of ​​the retina to the optical stimulus applied to the corresponding first subarea of ​​the retina. The corresponding ORG data has the same Figure 5 The same format as described in ORG data 150.

[0145] Note that, as in the present example embodiment, the controller 140 may first acquire a first indicator of the plurality of indicators 141 and use the first indicator to acquire first OCT data corresponding to the first indicator. The controller 140 may then repeat the OCT data acquisition process (workflow) using each of the remaining indicators of the plurality of indicators 141 until corresponding OCT data has been acquired for each of the remaining indicators 141. The controller 140 may then repeat the OCT data acquisition process (workflow) using each of the remaining indicators 141. Figure 7 The corresponding OCT data is processed in process S74 to generate corresponding ORG data. However, the generation of ORG data can be performed in parallel with the acquisition of corresponding OCT data. That is, after acquiring the first corresponding OCT data, the controller 140 can start executing process S74 to generate corresponding ORG data based on the first corresponding OCT data, and repeat the above workflow for each of the remaining indicators 141, generating corresponding ORG data based on the corresponding OCT data corresponding to each of the multiple indicators in parallel when acquiring the corresponding OCT data. In addition, Figure 7 The process S71 may be performed to acquire all of the multiple indicators before performing any one of the processes S72, S73, and S54 for a first indicator of the multiple indicators.

[0146] The controller 140 may perform the following operations only during an ORG capture session (for all of the plurality of indicators 141) after a single dark adaptation period of the retina of the eye 160. Figure 7 Processes S72 and S73 of the FD-OCT imaging system 130. This is made possible by a combination of limiting the applied optical stimulation to a first subdivision of the retina that is smaller than the field of view of the FD-OCT imaging system 130 and varying the location of the applied optical stimulation on the retina between multiple different locations on the retina through the optical system 120. Because the optical stimulation applied to each of the first subdivisions of the retina of the eye 160 does not provide stimulation in any other first subdivision of the retina of the eye 160, the need to provide a dark adaptation period after each application of the optical stimulation to the retina of the eye 160 (as in the prior art ORG techniques described in the background section) is avoided. In addition, the controller 140 can perform processes S72 and S73 (for all multiple indicators) to obtain ORG data for multiple retinal locations on a time scale that is much smaller than the time scale required for light adaptation (for example, within a time period of no more than 0.1 seconds, 1 second, or 3 seconds), which is not achievable using the conventional methods described above.

[0147] Note that the controller 140 may first acquire corresponding second indicators for multiple second partitions of the retina at which corresponding OCT data are to be acquired, and may then generate multiple indicators 141 so that when optical stimulation is applied to a first partition of the retina, each first partition of the retina (whose position on the retina is indicated by a corresponding one of the indicators 141) stimulates at least a portion of the corresponding second partition of the retina (i.e., so that corresponding OCT data may be generated based on the corresponding OCT data at the corresponding second partition of the retina).

[0148] FIG. 8A to FIG. 8E yes Figure 7 Schematic diagrams of an example first subarea of ​​the retina of eye 160 and an example second subarea of ​​the retina of eye 160 in processes S72 and S73 of the present invention, wherein the two subareas are illuminated by any implementation of optical system 120 and imaged by any implementation of FD-OCT imaging system 130 (e.g., optical system 300 and FD-OCT imaging system 320), respectively, according to example embodiments, unless otherwise noted. These figures illustrate the same 6A to 6F The field of view of the FD-OCT imaging system 130 shown in FIG. 1 corresponds to a region 600 of the eye 160 .

[0149] Fig. 8A shows an ORG capture session as Figure 7 The multiple first partitions 801 to 807 of the example of the multiple first partitions in the process S72, and as Figure 7 The controller 140 performs processes S72 and S73 to stimulate the first partition and obtain OCT data 135 from the corresponding second partition, for each pair of the first partition 801 and the second partition 811, the first partition 802 and the second partition 812, the first partition 803 and the second partition 813, etc., which are described above with respect to the example of the multiple second partitions 811 to 817 in the process S73. Figure 6C The straight line first partition 630 and the second partition 631 are sequentially arranged at different positions on the retina in the manner described.

[0150] Figure 8B shows an ORG capture session as Figure 7 The multiple first partitions 821 to 824 of the example of the multiple first partitions in the process S72, and as Figure 7The controller 140 performs processes S72 and S73 to stimulate the first partition and obtain OCT data 135 from the corresponding second partition, which are described above with respect to each pair of the first partition 821 and the second partition 825, the first partition 822 and the second partition 826, the first partition 823 and the second partition 827, etc. Fig. 6F The straight lines in the first partition 660 and the second partition 661 are sequentially arranged at different positions on the retina in the manner described.

[0151] Figure 8C shows an ORG capture session as Figure 7 The multiple first partitions 831 to 834 of the example of the multiple first partitions in the process S72, and as Figure 7 The multiple second partitions 835 to 838 of the example of the multiple second partitions in the process S73 of the eye 160 can be used to perform radial trend analysis of the eye 160 by analyzing the change of the retinal response of the eye 160 with the eccentricity of the eye 160 (for example, from the periphery of the eye 160 to the fovea of ​​the eye 160). For example, for each pair of the first partition 831 and the second partition 835, the first partition 832 and the second partition 836, the first partition 833 and the second partition 837, etc., the controller 140 performs the processes S72 and S73 to stimulate the first partition and obtain OCT data 135 from the corresponding second partition, and these first partitions and second partitions are based on the reference Figure 6C The straight line first partition 630 and the second partition 631 are sequentially arranged at different positions on the retina along a line in the manner described.

[0152] Fig.8D shows an ORG capture session as Figure 7 The multiple first partitions 841 to 844 of the example of the multiple first partitions in the process S72 in the embodiment of the present invention, and as Figure 7 The multiple second partitions 845 to 848 of the example of the multiple second partitions in the process S73 of the eye 160 can also be used to perform a radial trend analysis of the eye 160, in which the retinal response of the eye 160 is analyzed as a function of the eccentricity of the eye 160. To achieve this, each of the first partition and the second partition can form a concentric annular area centered on the fovea of ​​the eye 160, which corresponds to different degrees of eccentricity of the eye 160. For each pair of the first partition 841 and the second partition 845, the first partition 842 and the second partition 846, the first partition 843 and the second partition 847, etc., the controller 140 performs the processes S72 and S73 to stimulate the first partition and obtain OCT data 135 from the corresponding second partition, which are the first partitions and the second partitions as mentioned above. Figure 6BThe hollow circular first partition 620 and the second partition 621 are sequentially arranged at different distances from the fovea of ​​the retina in the manner described above.

[0153] Fig. 8E shows an ORG capture session as Figure 7 The multiple first partitions 851, 852, 855, 856 of the example of the multiple first partitions in the process S72, and as Figure 7 The controller 140 performs processes S72 and S73 to stimulate the first partition and obtain OCT data 135 from the corresponding second partition, and the first partition and the second partition are each based on the reference. Figure 6C In this case, the controller 140 controls the optical system 120 to apply the first optical stimulus to the first subareas 851 and 852 on the retina, and to apply the second optical stimulus to the second subareas 855 and 856, wherein the first optical stimulus is different from the second optical stimulus (for example, two different wavelengths of light are generated by the light source of the optical system 120, or the optical system 120 includes two different light sources arranged to generate light of different wavelengths). Although two different optical stimuli are described, the optical system 120 is not limited thereto, and may be operable to generate additional different optical stimuli (for example, as described in reference Figure 3A 301 of the optical system 300).

[0154] Fig. 9 A first partition 901 and a second partition 902 in the region 600 are shown, and these partitions may be Figure 5 The first partition in process S52 and Figure 5 . The stimulus applied to the first partition 901 stimulates the first portion 903 of the second partition 902, but does not stimulate the second portion 904 of the second partition 902. Therefore, the second portion 904 provides a baseline unstimulated area that can be used for comparison and / or normalization purposes. This technique of partially stimulating the second partition (by performing temporal modulation of the signal used to generate the optical stimulus) can also be used in the above reference FIG. 8A to FIG. 8E Furthermore, while this technique has been described in conjunction with a rectilinear first subarea 630 and a rectilinear second subarea 631, it will be appreciated that the technique is not limited thereto and that the principles described may be applied to other geometries of the first and second subareas of the retina.

[0155] In some cases, controller 140 may advantageously break the processing of OCT data to generate ORG data 150 into smaller steps. Fig.10 An example first partition 1001 and an example second partition 1002 in the area 600 are shown, and these partitions can provide Figure 5 An example of the first partition in process S52 and the second partition in process S53, or respectively providing Figure 7 One of the plurality of first partitions in process S72 and Figure 7 One of the plurality of second partitions in the process S73. Fig.10 As shown, the OCT data of the second partition 1002 can be divided into subsets of OCT data corresponding to regions 1003 to 1007, respectively, and each of the subsets of OCT data can be processed separately using the above-mentioned technique to generate ORG data 150 for each of the portions 1003 to 1007 on the retina of the eye 160. For example, in the above-mentioned velocity-based ORG technique, the time series of partial B scans acquired from each of the regions 1003 to 1007 can be used as the time series of B scans in the algorithm to generate ORGs at corresponding positions of the time series of partial B scans. This technique of processing to segment the second partition can also be performed on at least some of the remaining portions of the plurality of second partitions (if any). In addition, although this technique has been shown and described in conjunction with the straight first partition 1001 and the straight second partition 1002, it will be appreciated that the technique is not limited thereto, and the principles described can be applied to other geometric structures of the first partition and the second partition of the retina.

[0156] As in the present exemplary embodiment, the controller 140 of the FD-OCT apparatus 100 may be configured to Figure 7Each of the second subdivisions of the retina of the described eye 160 stores corresponding ORG data generated for the second subdivision (the ORG data indicating a corresponding physiological response of the second subdivision of the retina to an optical stimulus applied to the corresponding first subdivision of the retina) in association with a corresponding indication of a location of a point in the field of view of the eye 160 that is optically conjugate with the location of the second subdivision on the retina of the eye 160 (e.g., the location of the point on the second subdivision, such as the geometric center of the second subdivision). The stored ORG data and the stored associated indications can provide an indication of retinal function of the eye 160 at multiple points in the field of view of the eye 160, which can help diagnose a range of pathological conditions of the eye. In addition, the stored ORG data and the stored associated indications can be used to supplement the results of a visual field test of the eye 160 (e.g., an automated static visual field test, a dynamic visual field test, or a frequency doubling visual field test), specifically by providing further information that can help establish the cause of any blind spots or reduced retinal sensitivity within the field of view of the eye 160 determined by the visual field test, as described in more detail below.

[0157] The data items stored in association with each other as described above by the controller 140 may be generated in different ways. For example (as shown below with reference to Fig.11 As discussed in more detail herein, the locations of points on the retina to be stimulated by the optical system 120 and to have OCT data acquired therefrom by the FD-OCT imaging system 130 (for use in generating ORG data by the controller 140) can be selected by the controller 140 based on predefined locations in the field of view of the eye 160. This approach may be useful in situations where the ORG data 150 generated by the controller 140 is to be compared to measurements that have been (or will be) acquired at those same locations in a field of view test.

[0158] Alternatively, the controller 140 may select the locations of points on the retina to be stimulated by the optical system 120 and to have OCT data acquired therefrom by the FD-OCT imaging system 130 based on an image of the retina of the eye 160, such that the ORG data 150 ultimately generated by the controller 140 is derived from one or more regions of interest for study of the retina. The ORG data 150 generated in this manner may be similarly compared to measurements that have been (or will be) acquired in a visual field test by mapping locations on the retina associated with items of OCT / ORG data to conjugate locations in the field of view of the eye 160. Although in this case the items of ORG data 150 and the measurements in the visual field test may not yet have been acquired at a set of corresponding points that are optically conjugate, a meaningful comparison may still be made. Refer below to Fig.11 This alternative is described in more detail.

[0159] Fig.11 1 is a flow chart illustrating a process by which the controller 140 may determine, based on points in the field of view of the eye, indicators of target locations on the retina to which optical stimulation is to be applied, and indicators of locations on the retina to which OCT data 135 is to be acquired, in order to facilitate comparison of the field of view test data with the ORG data 150 generated by the controller 140. The controller 140 may perform a reference Figure 7 The process is performed before the process described above, whereby the controller 140 controls the FD-OCT imaging system 130 to acquire corresponding OCT data of each of the plurality of second subareas of the retina of the eye 160 corresponding to the corresponding first subarea of ​​the retina to which the optical stimulus is applied. However, the controller 140 may alternatively control the FD-OCT imaging system 130 to acquire corresponding OCT data of each of the plurality of second subareas of the retina of the eye 160 corresponding to the corresponding first subarea of ​​the retina to which the optical stimulus is applied. Figure 7 The processes in Fig.11 process.

[0160] exist Fig.11 In process S1101, the controller 140 determines a corresponding indication of the position on the retina of each second subregion of the retina at which the FD-OCT imaging system 130 will acquire OCT data 135. The controller 140 achieves this by determining, for each of a plurality of independent points in the field of view of the eye 160, a corresponding indication of a corresponding position on the retina that is optically conjugate to the point. As in the present example embodiment, the plurality of points in the field of view of the eye 160 may be an arrangement of points (e.g., on a grid or array) for which the results of a visual field test (e.g., an automated static visual field test, a dynamic visual field test, or a frequency-doubling visual field test) may be used to compare with the ORG data 150 to be generated by the controller 140, such that the ORG data 150 may be acquired from subregions of the retina that are substantially the same as those that have been illuminated by the stimulus used in the visual field test and therefore have their response to the stimulus evaluated in the visual field test. For example, the plurality of points in the field of view may be provided by a visual field testing device, such as an Octopus 100. TM Field of view test equipment or Humphrey TM High Frequency Field Analyzer (HFA).

[0161] exist Fig.11 In process S1102, the controller 140 determines each indicator 141 of a plurality of indicators 141 indicating a target position on the retina to which optical stimulation will be applied by the optical system 120, so that the optical stimulation can be appropriately applied to stimulate the intended partition of the retina for which ORG data 150 is to be acquired. Fig.11 The determination in process S1102 is based on Fig.11The corresponding indication in the indication determined in process S1101 of the embodiment of the present invention indicates the location of the corresponding second subarea of ​​the retina. Here, at least a portion of the corresponding second subarea of ​​the retina is arranged relative to the first subarea, and its location is indicated by the indicator 141, so that the optical stimulation stimulus applied to the first subarea during the acquisition of at least some OCT data 135 is stimulated. For example, the corresponding first subarea and the second subarea may at least partially overlap. Once at least some (i.e., one or more) target position indicators have been determined in this manner, which indicate the target locations on the retina where the optical stimulation is to be applied, the above-referenced method can be started. Figure 7 The process of generating ORG data 150 is described.

[0162] The location of the second partition of the retina may include a representative location of the second partition of the retina (e.g., a point (e.g., a center point) along a scan line on the retina along which repeated B scans are taken as OCT data 135). Thus, the location of the second partition may be expressed in terms of Cartesian coordinates (x x ,y n ,z n ) or the position of a point defined in any other coordinate system relative to a reference position (e.g., a point on the retina through which the optical axis or visual axis of the eye 160 passes, or the position of an anatomical feature on the retina, such as the fovea or the optic disc). The corresponding position in the field of view of the eye 160 that is optically conjugate with the position of the second partition of the retina can be such a point, such that the position of the point can be defined, for example, according to a first angle α with the visual axis of the eye 160 (which is in the temporal-nasal direction of the eye 160) and a second angle β with the visual axis of the eye 160 (which is in the superior-inferior direction of the eye 160), or defined in any other suitable coordinate system.

[0163] Fig.12 is a flow chart showing a process by which a controller 140 may select a set of indicators 141, each indicating a target location on the retina where optical stimulation will be applied by the optical system 120, and a corresponding location where OCT data 135 will be acquired by the FD-OCT imaging system 130, and map the locations on the retina where the OCT data 135 has been acquired to corresponding locations in the field of view of the eye 160, so that the generated ORG data 150 may be compared with the results of a field of view test performed on the eye 160.

[0164] exist Fig.12 In process S1201, the controller 140 acquires a plurality of indicators 141 based on an image of the retina of the eye 160. The controller 140 may obtain the plurality of indicators 141 by using the received designation of the retinal position made by the user (e.g., as described above with reference to Figure 5The controller 140 may alternatively automatically acquire the plurality of indicators 141, for example, based on an image of the retina of the eye 160 and information indicating the spatial distribution of photoreceptor cells across the retina of the eye 160, which information may be estimated or predicted based on the results of previous studies (measurements) of the spatial distribution in the human retina, such as reported in JB Jonas et al., "Count and density of human retinal photoreceptors", Graefe's Arch Clin Exp Ophthalmol 230, pp. 505-510 (1992).

[0165] exist Fig.12 In process S1202, the controller 140 determines, based on the above information, a corresponding indication of the position of each second subarea of ​​the retina on the retina, at which OCT data will be acquired by the FD-OCT imaging system 130. The corresponding first subarea and second subarea may at least partially overlap (e.g., as described above with reference to Figure 3A and Figure 3B ), or they may be separated from each other but sufficiently close to each other (e.g., as may be seen above with reference to Figure 3E The optical arrangement described herein is implemented such that an optical stimulus applied to the first sub-region induces a response in the second sub-region of the retina.

[0166] exist Fig.12 In process S1203, the controller 140 determines, for each second partition of the retina, a corresponding indication of the position of a point in the field of view of the eye 160 that is optically conjugate with the position of the second partition on the retina. This may be performed by the controller 140 using a mapping between points on the retina of the eye 160 and optically conjugate points in the field of view of the eye 160. The mapping may be determined using any technique known to those skilled in the art. For example, the mapping may be based on a ray tracing model of the eye 160, or based on a ray tracing model of the eye defined, for example, by average parameters of a set of eyes sampled from a population.

[0167] Fig.13 is a schematic diagram of a tabular representation of a data structure 1300, such as may be stored by controller 140 in a memory of controller 140 in this example embodiment. Data structure 1300 contains in the first (optional) column of the table an indication of the location of the second subarea on the retina (x n ,yn ,z n ), in the second column of the table contains an indication of the position of a point in the eye's field of view that is conjugate with the position of the second partition (α n ,β n ), and the third column of the table contains the corresponding ORG data [XXX] n Thus, each row in the data structure 1300 stores a corresponding indication of the location of a corresponding second subarea on the retina (x n ,y n ,z n ), which is a corresponding indication of the position of a corresponding point in the field of view of the eye 160 that is conjugate with the position of the corresponding second partition (α n ,β n ) and is associated with the corresponding ORG data [XXX] n However, it will be appreciated that data structure 1300 is not limited thereto and may take other forms. Note that the header of each column is included for explanation purposes only and that ORG data [XXX] n can take different forms, such as the above Figure 5 The process S54 is described.

[0168] The stored corresponding ORG data and the associated corresponding indication of location in the field of view of the eye 160 can be used to supplement field of view testing of the eye 160, providing further information that may help determine the cause of any blind spots or reduced retinal sensitivity within the field of view of the eye 160.

[0169] Fig.14 is a flow chart illustrating a process by which, as in this example embodiment, the controller 140 may acquire data indicating how measurements of the subject's ability to see optical stimuli of corresponding different partitions on the retina confined to different corresponding locations on the retina of the eye 160 are distributed over at least a portion of the field of view of the eye 160, and control the graph display device 142 to display a first graph indicating how the subject's ability to see the optical stimuli with the eye 160 is distributed over at least a portion of the field of view of the eye 160, and a second graph indicating how the retina's response to the optical stimuli represented by the stored corresponding indications is distributed over at least a portion of the field of view of the eye 160, for comparison purposes.

[0170] exist Fig.14 In process S1401, the controller 140 acquires data indicating how measurements of the subject's ability to see optical stimuli of corresponding different partitions on the retina confined to different corresponding locations on the retina of the eye 160 are distributed over at least a portion of the field of view of the eye 160. Fig.15is a flow chart illustrating a process by which the controller 140 may acquire the data, as in this example embodiment.

[0171] refer to Fig.15 In process S1501, the controller 140 receives a corresponding indication provided by the subject as to whether the subject sees a corresponding optical stimulus for each of a plurality of first subareas of the retina applied by the optical system 120. For example, the FD-OCT apparatus 100 may include a button (e.g., which may be a physical button or a virtual button on a display of the FD-OCT apparatus 100) that may be pressed by the subject when the subject sees an optical stimulus provided by the optical system 120.

[0172] exist Fig.15 In process S1502, controller 140 associates each of the received indications with a corresponding indication of the location of the corresponding first partition on the retina. Controller 140 can achieve this by, for example, matching the indication received from the subject with one of the time periods during which optical system 120 applies optical stimulation to a first partition of the plurality of first partitions of the retina.

[0173] exist Fig.15 In process S1503, for each corresponding indication of the position of the corresponding first partition on the retina, the controller 140 determines a corresponding indication of the corresponding position of a point in the field of view of the eye 160 that is optically conjugate with the position of the corresponding first partition on the retina. The controller 140 may determine the corresponding indication of the corresponding position of the point in the field of view of the eye 160 that is optically conjugate with the position of the corresponding first partition on the retina, for example by using Fig.12 The technique described in process S1203 achieves this.

[0174] Controller 140 may alternatively acquire the above data (indicating how the measurements of the subject's ability to see optical stimuli constrained to respective different subareas on the retina at different respective locations on the retina of eye 160 are distributed over at least a portion of the visual field of eye 160) by receiving visual field test data that has been acquired from eye 160 (e.g., by a dynamic or static perimetry device). For example, the data may be acquired by using a computer such as, for example, Octopus TM Field of view test equipment or Humphrey TMThe visual field test device of the visual field analyzer (HFA) performs a visual field test on the eye 160 to obtain visual field test data from the eye 160. The visual field test data can more generally be obtained via various forms of visual field examination, including, for example, using a tangent screen, using Goldmann perimetry, automated perimetry, and microperimetry (which are described in more detail below). In addition, the form of visual field examination can use static or dynamic representations of visual field test stimuli, such as to perform static perimetry or dynamic perimetry, and the visual field test stimulus used can be selected to perform a photoreceptor-specific visual field examination, such as photopic perimetry or scotopic perimetry.

[0175] The visual field test data obtained from the eye 160 may include values ​​indicating the subject's ability to see an optical stimulus presented in the field of view of the eye 160 at each of a plurality of different locations in the field of view of the eye 160. For example, where the visual field test data is obtained from the eye 160 by performing a visual field test on the eye 160 using an HFA, the values ​​may indicate the patient's retinal sensitivity (e.g., in dB) in a digital display output from the FHA, or may be grayscale values ​​in a grayscale image output from the HFA. More generally, the values ​​may be binary (e.g., "1" or "0") depending on whether the subject indicated that they saw the optical stimulus, or may indicate a threshold light intensity at which the subject indicated that they could see the optical stimulus a certain percentage (e.g., 50%) of the time. Positions in the field of view of the eye 160 may be defined similarly to those with respect to Fig.11 However, it will be appreciated that the form of the visual field test data is not limited thereto, and any form of visual field test data acquired using a visual field test of the eye 160 may be used.

[0176] Reference again Fig.14 In the optional process S1402, the controller 140 performs the following operations based on Fig.14 The image display device 142 is controlled to display a first image indicating how the subject's ability to see optical stimuli with the eye 160 will be distributed over at least a portion of the visual field of the eye 160 (which may be indicated by at least some of the acquired visual field test data) based on at least some of the data acquired in process S1401. For example, in the case where the visual field test data is acquired from the eye 160 by performing a visual field test on the eye 160 using an HFA, the first image may be similar to a digital display or grayscale image output from the device.

[0177] Fig.16 Yes, you can Fig.14The example first diagram 1400 is shown in the process S1402 of FIG. In this example, the acquired data is the field of view test data obtained from the field of view test device. In this case, the field of view test data includes values ​​V1 to V 24 , as described above, each value indicates a threshold light intensity at which the subject indicates that they can see the visual field optical stimulus at that location 50% of the time, and the values ​​are plotted along a first axis 1410 corresponding to a first angle α and a second axis 1420 corresponding to a second angle β. However, depending on the type of visual field test used, the first graph 1400 may take other forms, such as a Goldmann visual field graph when the visual field test is performed using Goldmann perimetry.

[0178] Reference again Fig.14 In an optional process S1403, the controller 140 controls the map display device 142 to display a second map for comparison with the first map based on at least some of the stored ORG data 150 and corresponding stored indications of corresponding positions in the field of view of the eye 160. The second map indicates how the physiological response of the retina to the optical stimulus indicated by at least some of the stored ORG data 150 is distributed over at least a portion of the field of view of the eye 160.

[0179] Fig.17 It shows that it can be Fig.14 The example second graph 1500 shown in process S1403 of FIG. The second graph 1500 shows the stored ORG data I1 to I2 on a graph of the field of view of the eye similar to the first graph 1400. 16 , as described above, the data indicates the retinal response at the corresponding position of the second subarea on the retina. As in this example embodiment, the stored ORG data I1 to I 16 The amplitude of the preliminary "alpha wave" in the retinal response at the corresponding position of the second subarea on the retina (or the amplitude of the "beta wave" in the retinal response) can be indicated. For example, the second graph 1500 can be displayed on the graph display device 142 adjacent to the first graph 1400 to facilitate comparison of the two graphs. However, the second graph 1500 can alternatively be superimposed on the first graph 1400 so that the acquired visual field test data V1 to V 24 and the stored ORG data I1 to I 16 A first axis 1410 corresponding to a first angle α and a second axis 1420 corresponding to a second angle β are shown on a single graph.

[0180] For comparison purposes, in the field of view of eye 160 Fig.14 The second diagram of process S1403 shows that the location of the stored ORG data 150 can be compared with Fig.14The data obtained in process S1401 is displayed in Fig.14 The first graph of process S1402 of FIG. 1404 is the same as the first graph of process S1402, thereby allowing the data acquired at each position to be easily and directly compared with the ORG response of the eye 160 at that same position. This can help to increase the certainty of the diagnosis of the cause of any defect in the visual field of the eye 160. This can be described above with respect to Fig.11 The process described in the embodiment of the present invention may be particularly advantageous in the case where the first and second figures are superimposed because the clinician can view the corresponding ORG data 150 and the acquired data at each location side by side (e.g., by displaying the corresponding values ​​of the stored ORG data and the corresponding values ​​of the visual field test data side by side at each location).

[0181] exist Fig.14 In the optional process S1404 of the embodiment, the controller 140 compares the data of the first graph with the data of the second graph, and identifies at least one area of ​​at least a portion of the field of view based on the comparison. The controller 140 may identify at least one of the following based on the comparison: one or more first areas, one or more second areas, one or more third areas, and one or more fourth areas of the field of view or a portion thereof shown in the graph. As in the present example embodiment, each of these areas may be identified by the controller 140 by determining whether the value of the field of view test data at the corresponding position in the field of view of the eye 160 indicates that the subject is able to see the optical stimulus at each corresponding position (in the field of view) (e.g., with a certain light intensity at least 50% of the time), and whether the corresponding ORG data at each corresponding position (e.g., the same position or the position closest to the corresponding position compared to the other remaining corresponding positions) indicates a physiological response to the optical stimulus that satisfies a predetermined condition. Satisfying the predetermined condition may indicate that the physiological response to the optical stimulus indicates the physiological response of a healthy eye to the optical stimulus (i.e., a healthy retinal response). For example, where the corresponding ORG data includes a set of values, each value indicating the magnitude of a retinal response to an optical stimulus, the predetermined condition may be that the value is greater than or equal to a threshold value. Thus, a value greater than or equal to the threshold value may indicate a healthy retinal response, while a value less than the threshold value may indicate an unhealthy retinal response. As in the present example embodiment, the comparison performed by the controller 140 may allow the relationship between the data of the first graph and the data of the second graph to be classified into one of the aforementioned four categories for each of a plurality of regions into which the first graph and the second graph may be divided in any suitable manner.

[0182] In this example embodiment, one or more first regions (i.e., different first regions) of the displayed field of view indicate that the subject is able to see the optical stimulus in the one or more first regions, and further indicate that one or more corresponding regions of the retina provide a physiological response to the optical stimulus that satisfies a predetermined condition. Therefore, these one or more first regions can be considered to correspond to regions of the retina with healthy (normal) function.

[0183] One or more second areas (i.e., different second areas) of the displayed visual field indicate that the subject cannot see the optical stimulus in the one or more second areas, and further indicate that one or more corresponding areas of the retina provide a physiological response to the optical stimulus that satisfies a predetermined condition. Therefore, these one or more second areas can be considered to correspond to areas of the retina where, although the retina responds normally to the optical stimulus, the subject cannot see the applied stimulus (but this does not exclude that the subject may have been able to see higher intensity stimuli if these stimuli had been applied in the visual field test). This indicates to the clinician that the reason why the subject cannot see is unlikely to be retinal photoreceptor dysfunction, but may originate elsewhere, such as the communication pathways between the retinal photoreceptors and the subject's brain. This can guide the clinician to reach a correct diagnosis more quickly.

[0184] One or more third regions of the displayed visual field (i.e., different third regions) indicate that the subject can see the optical stimulus in the one or more third regions, and further indicate that one or more corresponding regions of the retina provide a response to the optical stimulus that does not meet a predetermined condition. Thus, these one or more third regions can be associated with subjects who erroneously indicated that they can see the optical stimulus. These regions can be re-investigated through further visual field testing, or excluded from (or weighted with a reduced confidence in) the functional analysis of the retina, thereby further improving the accuracy of any diagnosis made by the clinician.

[0185] The one or more fourth areas of the displayed field of view (i.e., different fourth areas) indicate that the subject cannot see the optical stimulus in the one or more fourth areas, and further indicate that one or more corresponding areas of the retina provide a physiological response to the optical stimulus that does not meet the predetermined condition. Therefore, these one or more fourth areas correspond to one or more areas of the retina that are not functioning healthily, and identification of these areas can save the clinician's time by initially focusing the clinician's attention on these areas when performing an analysis of the retinal function of the eye 160.

[0186] Optionally, in Fig.14In process S1405, the controller 140 controls the map display device 142 to display any identified area indicating at least a portion of the field of view of the eye 160 in at least one of the first map, the second map, and the third map. Fig.18 An example third graph 1600 is shown, which may be viewed in Fig.14 The third figure 1600 is displayed by the figure display device 142 in the process S1405 of the example first figure 1400. The third figure 1600 is on a drawing similar to the example first figure 1400 and the example second figure 1500 (i.e., a drawing along the first axis 1410 corresponding to the first angle α and the second axis 1420 corresponding to the second angle β). The third figure 1600 shows the area 1601 as the first area identified as described above, the two areas 1602 and 1603 as the second areas identified as described above, the area 1604 as the third area identified as described above, and the three areas 1605, 1606 and 1607 as the fourth area identified as described above. As described above, these areas 1601 to 1607 can alternatively be shown as superimposed on the first figure, the second figure, or superimposed on the superposition of the first figure and the second figure.

[0187] While the display of a first graph indicating the ability of a subject to see optical stimulation as distributed over at least a portion of the field of view of the eye 160 and a second graph indicating the physiological response of the retina to the optical stimulation as distributed over at least a portion of the field of view of the eye 160 indicated by the stored respective indications has been described above, in an alternative implementation of the example embodiment, the controller 140 may control the graph display device 142 to display a fourth graph indicating the ability of a subject to see optical stimulation with the eye 160 as distributed over at least a portion of the retina of the eye 160 and a fifth graph indicating the physiological response of the retina to the optical stimulation as distributed over at least a portion of the retina of the eye 160 indicated by at least some of the stored ORG data. This may be preferred for clinicians because it allows the visual field test data and the ORG data to be compared when overlaid on an image of the retina of the eye 160, thereby enabling, for example, the use of both sets of data to interpret structural features of the eye 160 in the image. Specifically, the fourth map may be a map obtained from a microperimetry test of the eye 160, thereby allowing the corresponding ORG data to be mapped to and displayed together with the microperimetry results acquired by the controller 140, as described below.

[0188] Fig.19is a flow chart illustrating a process by which, as in an alternative implementation of the example embodiment, the controller 140 may acquire data indicating how measurements of the subject's ability to see corresponding different partitions of the retina confined to different corresponding locations on the retina of the eye 160 are distributed over at least a portion of the retina of the eye 160, and control the image display device 142 to display the fourth and fifth images.

[0189] exist Fig.19 In process S2101, the controller 140 stores, for each of a plurality of second partitions of the retina, corresponding ORG data 150 generated from the OCT data 135 acquired from the second partition in association with a corresponding indication of the position of the second partition on the retina.

[0190] exist Fig.19 In process S2102, the controller 140 acquires data indicating how the measurement results of the subject's ability to see optical stimuli of corresponding different partitions on the retina confined to different corresponding positions on the retina of the eye 160 are distributed on at least a portion of the retina. Fig. 20A is a flow chart illustrating a process by which the controller 140 may acquire the data, as in this example embodiment.

[0191] refer to Fig. 20A In process S1901, controller 140 receives visual field test data acquired from eye 160 by a visual field test device, the visual field test data including measurement results of a subject's ability to see optical stimuli applied from multiple points in the visual field of the subject's eye 160. For example, controller 140 may acquire visual field test data from HFA or other visual field tests such as those described above.

[0192] exist Fig. 20A In process S1902, the controller 140 determines, for each of a plurality of points in the field of view of the eye 160, a corresponding indication of a corresponding position on the retina that is optically conjugate to the point. The controller 140 may achieve this by using a mapping between the coordinates of a first point in the field of view of the eye and the coordinates of a second point on the retina that is optically conjugate to the first point to generate distribution information, which mapping may be obtained as described above.

[0193] As an alternative to processes S1901 and S1902, controller 140 may receive visual field test data acquired from eye 160 by a visual field test device, the visual field test data indicating how the measurement results of the subject's ability to see optical stimuli applied to corresponding different locations on the retina of eye 160 are distributed on at least a portion of the retina of eye 160. For example, the visual field test data may be acquired from a microperimetry device (e.g., Nidek TMMP-3 microperimeter, ZeissHumphrey TM Visual Field Analyzer Model 860 or Haag-Streit Octopus 900 Pro TM ) is acquired, the output of the device also including an indication of the location on the retina of the eye 160 to which the optical stimulus from the microperimeter device is delivered (for example, in the form of coordinates of a point on the retinal image acquired by the microperimeter device) as distribution information.

[0194] Fig. 20B A flow chart showing a process by which the controller 140 may alternatively acquire the aforementioned data is shown.

[0195] exist Fig. 20B In process S1903, the controller 140 receives an indication provided by the subject as to whether the subject sees a corresponding optical stimulus for each of a plurality of first subareas of the retina applied by the optical system 120. For example, the FD-OCT apparatus 100 may include a button (e.g., which may be a physical button or a virtual button on a display of the FD-OCT apparatus 100) that may be pressed by the subject when the subject sees the optical stimulus provided by the optical system 120.

[0196] exist Fig. 20B In process S1904, controller 140 associates each of the received indications with a corresponding indication of the location of the corresponding first partition on the retina. Controller 140 can achieve this by, for example, matching the indication received from the subject with one of the time periods during which optical system 120 applies optical stimulation to a first partition of the plurality of first partitions of the retina.

[0197] Return to Fig.19 In an optional process S2103, the controller 140 controls the map display device 142 to display a fourth map based on at least some of the data acquired in the process S2101, the fourth map indicating how the subject's ability to see optical stimulation (with the eye 160) is distributed over at least a portion of the retina of the eye 160. The fourth map may include, for example, an image of a portion of the retina of the eye 160 acquired by a microperimeter device (e.g., by a scanning laser ophthalmoscope included in the microperimeter device) or by the FD-OCT apparatus 100 (e.g., by the FD-OCT imaging system 130 or a scanning laser ophthalmoscope forming a portion of the FD-OCT apparatus 100).

[0198] Fig.21 An example fourth graph 1700 is shown, which shows the Fig.16 The values ​​V1 to V in the example first graph 1400 24, although these are distributed over the image of area 800 of the retina of eye 160. Values ​​V1 to V 24 The position in area 800 comes from the distribution information.

[0199] exist Fig.19 In the optional process S2104 of the embodiment, the controller 140 controls the map display device 142 to display a fifth map for comparison with the fourth map based on at least some of the generated ORG data and the position of the second partition of the retina from which at least some of the ORG data is generated, the fifth map indicating how the physiological response of the retina to the optical stimulus indicated by at least some of the stored ORG data 150 is distributed over at least a portion of the retina of the eye 160. The fifth map may include an image of a portion of the retina of the eye 160 in the same manner as described above for the fourth map.

[0200] Fig. 22 An example fifth graph 1800 is shown, which shows the Fig.17 The example second figure 1500 stores the ORG data I1 to I 16 , although these Fig. 22 The ORG data I1 to I2 are distributed in the image of the area 800 of the retina of the eye 160. 16 The position in region 800 is determined as described above, and as described above, can be set to the same position as the value of the visual field test data on the retina of eye 160 by using the distribution information in process S2102 to determine, for example, Figure 7 The multiple indicators in the process S71 or in Figure 7 The location of the second partition is determined in process S73. Using the same location for the values ​​of the corresponding ORG data 150 and visual field test data can facilitate side-by-side comparison of the data sets by the clinician, thereby allowing direct correlation between the data sets at each location.

[0201] The fourth and fifth images may be superimposed in the same manner as described above with respect to the first and second images. In addition, the controller 140 may identify one or more first areas, one or more second areas, one or more third areas, and one or more fourth areas as being distributed on at least a portion of the retina of the eye 160 by comparing the fourth and fifth images in the same manner as described above with respect to the first and second images. In addition, these identified areas may be displayed by the image display device 142 in at least one of the fourth, fifth, and sixth images in the same manner as described above with respect to the first, second, and third images, indicating at least a portion of the retina of the eye 160. Note that the controller 140 may perform the above process to control the image display device 142 to display at least one of the fourth, fifth, and sixth images in addition to at least one of the first, second, and third images.

[0202] Various additional variations and modifications may be made to the exemplary embodiments described above.

[0203] For example, although some of the examples of the optical system 120 described above employ scanning elements 363 and 364 or a single two-dimensional scanner 373 to convert the light L s is directed to the retina of the eye 160, and changes the light L applied to the retina of the eye 160 s position, but one or more scanning elements of a different kind may alternatively be used for this purpose.

[0204] For example, one or more refractive scanning elements may be used instead of one or more refractive elements. Fig.23A As schematically shown in FIG. 1 , the light beam L s can be arranged to be incident on a scanning element in the form of a rotatable wedge prism 383, and the wedge prism 383 can be driven (for example by a galvanometer or other rotation drive mechanism) to rotate about a rotation axis that can be aligned with the beam L s The propagation direction of the beam L is aligned and thus deflected s to propagate in a direction determined by the rotational position of the wedge prism 383. In some variations, a second wedge prism 384 may be added to provide a so-called Risley prism scanner, in which the two wedge prisms 383 and 384 are independently rotatable about respective rotation axes, which may be aligned (parallel) to each other and in some cases coincident, such as Fig. 23B This configuration of two or more wedge prisms can allow the beam L to be more uniform compared to a single wedge prism. s is turned at more locations on the retina.

[0205] The optical system 120 may be configured to change the location on the retina where the optical stimulus is to be applied in yet other ways. For example, instead of using the scanning elements 363 and 364, a single two-dimensional scanner 373, or one or more wedge-shaped prisms 383, 384 described above, the optical system 120 may be arranged to direct the light L s The light L from the optical fiber 393 is projected onto the retina of the eye 160 via the optical fiber 393 and at least one lens 394, which is arranged to focus the light L from the optical fiber 393. s , where the optical fiber 393 has a light s The end portion from which the light is emitted can be moved relative to at least one lens 394 in a direction that is perpendicular to the direction of the light L s In the direction of propagation between the end of the optical fiber 393 and at least one lens 394. Fig.24 Thus, the position on the retina where the optical stimulus is to be applied can be changed by moving the end of the optical fiber 393 along Fig.24 at least one lens 394 is moved along direction 395 while the end of optical fiber 393 is kept stationary; at least one lens 394 is moved along direction 395 while the end of optical fiber 393 is kept stationary; or Fig.24 Any other relative movement in direction 395.

[0206] With respect to example embodiments including the dynamic amplitude mask described above, it should be noted that, regardless of the form in which it is implemented, the dimensions of the dynamic amplitude mask can be set to allow unmasked subdivisions thereof to illuminate any location on the retina of the eye 160. However, there is a risk that some or all elements of the dynamic amplitude mask (e.g., some or all of the micromirrors, in the case where the dynamic amplitude mask is provided in the form of a DMD as described above) may fail and thereby cause the eye 160 to be illuminated by an optical power that may exceed a safe limit. To address this issue, in some example embodiments, the dimensions of the dynamic amplitude mask are set (made small enough) so that in the event of a complete failure of the dynamic amplitude mask, the optical power it directs toward the eye 160 (where substantially all light incident on the dynamic amplitude mask is directed toward the eye 160) remains below a predetermined threshold level that is safe for the eye 160. In this case, as described above, Fig.25As shown, the limitation of the size of the dynamic amplitude mask 401 can be compensated by providing a galvanometer scanner or other beam steering mechanism 402 in the optical path between the dynamic amplitude mask 401 and the eye 160, which beam steering mechanism 402 can be controlled by the controller 140 to steer the light from the dynamic amplitude mask 401 to the target location on the retina indicated by the indicator 141. Thus, the location on the retina where the optical stimulus is to be applied can be adjusted in part by the configuration of the unmasked portion of the dynamic amplitude mask 401, and in part by the beam steering mechanism 402, both of which can be controlled by the controller 140. Fig.25 The relay system 403 shown in FIG. 4 includes reference Figure 3A and Figure 3C The mirror-based relay system described above (including curved mirrors 313 and 315), and the Figure 3B and 3D to Figure 3F A lens-based relay system of the type described (including lens relay 334).

[0207] In the foregoing description, example aspects have been described with reference to several example embodiments. Therefore, the description should be regarded as illustrative rather than restrictive. Similarly, the drawings shown in the accompanying drawings highlighting the features and advantages of the example embodiments are presented for illustrative purposes only. The architecture of the example embodiments is sufficiently flexible and configurable that it can be utilized in ways other than those shown in the accompanying drawings.

[0208] In an example embodiment, some aspects of the examples given herein, such as the functions of the controller 140, may be provided as a computer program or software, such as one or more programs having instructions or instruction sequences, included or stored in an article of manufacture, such as a machine-accessible or machine-readable medium, an instruction memory, or a computer-readable storage device, each of which may be non-transitory. The program or instructions on a non-transitory machine-accessible medium, a machine-readable medium, an instruction storage device, or a computer-readable storage device may be used to program a computer system or other electronic device. The machine-readable medium or computer-readable medium, the instruction storage device, and the storage device may include, but are not limited to, a floppy disk, an optical disk, and a magneto-optical disk or other types of media / machine-readable media / instruction storage devices / storage devices suitable for storing or transmitting electronic instructions. The techniques described herein are not limited to any particular software configuration. They may be applied in any computing or processing environment. The terms "computer-readable", "machine-accessible medium", "machine-readable medium", "instruction storage device", and "computer-readable storage device" used herein shall include any medium capable of storing, encoding, or transmitting instructions or instruction sequences for execution by a machine, a computer, or a computer processor and causing the machine / computer / computer processor to perform any of the methods described herein. Furthermore, it is common in the art to refer to software in one form or another (e.g., program, procedure, process, application, module, unit, logic, etc.) as taking an action or causing a result. Such expressions are merely a shorthand way of stating that execution of the software by a processing system causes the processor to perform an action to produce a result.

[0209] Some or all of the functions of controller 140 may also be implemented by preparing an application specific integrated circuit, a field programmable gate array, or by interconnecting an appropriate network of conventional component circuits.

[0210] The computer program product may be provided in the form of one or more storage media, instruction storage means or storage devices having stored thereon or therein instructions that can be used to control or cause a computer or computer processor to perform any process of the example embodiments described herein. The storage medium / instruction storage means / storage device may include, by way of example and without limitation, an optical disk, ROM, RAM, EPROM, EEPROM, DRAM, VRAM, flash memory, flash memory card, magnetic card, optical card, nanosystem, molecular memory integrated circuit, RAID, remote data storage / archiving / warehousing device, and / or any other type of device suitable for storing instructions and / or data.

[0211] Some embodiments stored on any one of one or more computer-readable media, instruction storage devices, or storage devices include hardware for controlling the system and software for enabling the system or microprocessor to interact with a human user or other mechanism using the results of the example embodiments described herein. Such software may include, without limitation, device drivers, operating systems, and user applications. Ultimately, as described above, such computer-readable media or storage devices also include software for executing example aspects of the present invention.

[0212] Software modules for implementing the processes described herein are included in the programming and / or software of the system. In some example embodiments herein, the modules include software, but in other example embodiments herein, the modules include hardware or a combination of hardware and software.

[0213] Although various exemplary embodiments of the present invention have been described above, it should be understood that they are presented by way of example and not limitation. It will be apparent to those skilled in the relevant art that various changes may be made in form and detail. Therefore, the present invention should not be limited to any of the exemplary embodiments described above, but should be defined only in accordance with the appended claims and their equivalents. It should also be understood that any process recited in a claim need not be performed in the order presented.

[0214] Although this specification contains many specific embodiment details, these should not be understood as limitations on the scope of any invention or content that may be claimed, but should be understood as descriptions of features specific to the specific embodiments described herein. Certain features described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination. In addition, although features may be described above as acting in a specific combination and even initially claimed as such, one or more features from the claimed combination may be deleted from the combination in some cases, and the claimed combination may be directed to a sub-combination or a variant of the sub-combination.

[0215] In some cases, multitasking and parallel processing may be advantageous. In addition, the separation of the various components in the above-described embodiments should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

[0216] Now that some illustrative embodiments and embodiments have been described, it is apparent that the foregoing embodiments are illustrative rather than restrictive and have been presented by way of example. In particular, although many of the examples presented herein relate to specific combinations of devices or software elements, these elements may be combined in other ways to achieve the same purpose. Actions, elements, and features discussed only in conjunction with one embodiment are not intended to be excluded from similar roles in the embodiments or other embodiments.

Claims

1. A Fourier domain optical coherence tomography (FD-OCT) device (100) arranged to acquire optical retinal imaging (ORG) data (150) indicative of a physiological response of a retina of an eye (160) of a subject to an optical stimulus, the FD-OCT device (100) comprising: a fixation target (110) arranged to fix a gaze direction (161) of the eye (160); an optical system (120) operable to apply the optical stimulus to the retina such that illumination of the retina by the optical stimulus is limited to a subarea of ​​the retina, the optical system (120) being controllable to change a location on the retina to which the optical stimulus is to be applied; an FD-OCT imaging system (130) operable to acquire OCT data (135) by imaging subareas of the retina of the eye (160); and A controller (140), the controller being arranged to: Acquiring (S51) an indicator (141) of a target location on the retina to which the optical stimulus is to be applied by the optical system (120); When the position of the fixation target (110) relative to the eye (160) remains fixed, controlling the optical system (120) using the indicator (141) obtained (S52) to apply the optical stimulus to a first subarea of ​​the retina at the target position; controlling (S53) the FD-OCT imaging system (130) to acquire OCT data (135) of a second subregion of the retina, wherein at least a portion of the second subregion of the retina is arranged relative to the first subregion so as to be stimulated by the applied optical stimulus during acquisition of at least some of the OCT data (135); and The ORG data (150) is generated (S54) based on the acquired OCT data (135).

2. The FD-OCT device (100) according to claim 1, wherein: The optical system (120, 300) comprises a light source (301) arranged to generate light providing the optical stimulus, and one or more scanning elements (312, 314; 363, 364) arranged to direct the light to the retina, and The controller (140) is arranged to control the one or more scanning elements (312, 314; 363, 364) using the acquired indicator (141) to direct light to the first subarea of ​​the retina located at the target position when the position of the fixation target relative to the eye remains fixed.

3. The FD-OCT device (100) according to claim 2, wherein: The FD-OCT imaging system (130, 320) comprises: an interferometer (322) having a sample arm (324) and a reference arm (325); and A detector (323) arranged to detect sample OCT light (L) propagating along the sample arm (324) after having been scattered from the retina o ) and the reference OCT light (L) propagating along the reference arm (325) r ) and At least one of the one or more scanning elements (312, 314) is further arranged to transmit the sample OCT light (L o ) is directed toward the second partition of the retina, and the sample OCT light (L) scattered from the second partition of the retina o ) is directed toward the detector (323).

4. The FD-OCT device (100) according to claim 2, wherein: The FD-OCT imaging system (120, 361) comprises: an interferometer (322) having a sample arm (324) and a reference arm (325); one or more scanning elements (312, 314); and A detector (323) arranged to detect sample OCT light (L) propagating along the sample arm (324) after having been scattered from the retina o ) and the reference OCT light (L) propagating along the reference arm (325) r ) The one or more scanning elements (312, 314) are arranged to transmit the sample OCT light (L o ) is directed toward the second subarea of ​​the retina, and the sample OCT light (L) scattered from the second subarea of ​​the retina o ) directed toward the detector (323); and One or more scanning elements (363, 364) of the optical system (120, 360) are different from one or more scanning elements (312, 314) of the FD-OCT imaging system (120, 361).

5. The FD-OCT device (100) according to claim 4, wherein: The controller (140) is arranged to use the acquired indicator (141) to control one or more scanning elements (363, 64) of the optical system (130, 361) independently of one or more scanning elements (312, 314) of the FD-OCT imaging system (120, 360) when the position of the fixation target (110) relative to the eye (160) remains fixed.

6. The FD-OCT device (100) according to any preceding claim, wherein: The controller (140) is arranged to: Acquiring (S71) a plurality of indicators (141), each indicator indicating a corresponding target location on the retina to which the optical stimulus is to be applied by the optical system (120); controlling the optical system (120) using (S72) the acquired indicator (141) to apply the optical stimulus to a respective independent first subarea of ​​the retina at the respective target location while the position of the fixation target relative to the eye remains fixed; controlling (S73) the FD-OCT imaging system (130) to acquire, for each of the first subareas of the retina, corresponding OCT data (135) of a corresponding second subarea of ​​a plurality of second subareas of the retina, wherein at least a portion of the corresponding second subarea of ​​the retina is arranged relative to the corresponding first subarea of ​​the retina so as to be stimulated by the applied optical stimulus during acquisition of at least some of the corresponding OCT data (135); and The respective OCT data (135) of each second sub-division of the retina is processed (S74) to generate respective ORG data indicative of a respective physiological response of the second sub-division of the retina to the optical stimulus applied to the corresponding first sub-division of the retina.

7. The FD-OCT device (100) according to claim 6, wherein: In a period not exceeding 3 seconds: The controller (140) is arranged to use the acquired indicator (141) to control the optical system (120) to apply the optical stimulus to a corresponding first subregion of the retina; and The controller (140) is arranged to control the FD-OCT imaging system (130) to acquire corresponding OCT data (135) for each of the first subregions of the retina.

8. The FD-OCT device (100) according to claim 6 or claim 7, wherein: The controller (140) is also arranged to: For each second subregion of the retina, corresponding ORG data (135) generated for the second subregion is stored in association with a corresponding indication of the position of a point in the field of view of the eye (160) that is optically conjugate with a corresponding position of the second subregion on the retina.

9. The FD-OCT device (100) according to claim 8, wherein: The controller (140) is also arranged to: determining (S1101) a corresponding indication of a position on the retina for each second subarea of ​​the retina at which OCT data is to be acquired by the FD-OCT imaging system (130) by determining, for each point among a plurality of points in the field of view of the eye (160), a corresponding indication of a corresponding position on the retina that is optically conjugate with the point; and Each of the plurality of indicators (141) is determined (S1102) based on a corresponding indication in the determined indication representing a position of a corresponding second partition of the retina, wherein at least a portion of the corresponding second partition of the retina is arranged relative to the first partition so as to be stimulated by the applied optical stimulus during the acquisition of at least some of the OCT data (135), the position of the first partition being indicated by the indicator (141).

10. The FD-OCT device (100) according to claim 8, wherein: The controller (140) is also arranged to: acquiring (S1201) the plurality of indicators (141) based on an image of a retina of the eye (160); determining (S1202) a corresponding indication of a location on the retina for each second subarea of ​​the retina at which OCT data is to be acquired by the FD-OCT imaging system (130), based on a corresponding indicator of the plurality of indicators (141); and For each second subdivision of the retina, a corresponding indication of the position of a point in the field of view of the eye (160) that is optically conjugate with the position of the second subdivision on the retina is determined (S1203).

11. The FD-OCT apparatus (100) according to any one of claims 8 to 10, further comprising a display device (142), wherein the controller (140) is further arranged to: Acquiring (S1401) data indicating how measurements of the subject's ability to see optical stimuli confined to respective different subareas on the retina at different respective locations of the retina of the eye (160) are distributed over at least a portion of the field of view of the eye (160); Based on at least some of the acquired data, controlling (S1402) the display device (142) to display a first graph (1400) indicating how the subject's ability to see the optical stimulus is distributed over at least a portion of the field of view of the eye (160); and Based on at least some of the stored ORG data (150) and associated stored indications, control (S1403) the display device (142) to display a second graph (1500) for comparison with the first graph (1400), wherein the second graph (1500) indicates how the physiological response of the retina to the optical stimulus, as indicated by at least some of the stored ORG data (150), is distributed over at least a portion of the field of view of the eye (160).

12. The FD-OCT device (100) according to claim 6 or claim 7, wherein: The controller (140) is also arranged to: storing (S2101), for each of a plurality of second subareas of the retina, respective ORG data (150) generated from OCT data (135) acquired from the second subarea in association with a respective indication of the location of the second subarea on the retina; and Acquire (S2102) data indicating how measurements of the subject's ability to see optical stimuli of corresponding different partitions on the retina confined to different corresponding locations on the retina of the eye (160) are distributed over at least a portion of the field of view of the eye (160).

13. The FD-OCT apparatus (100) according to claim 12, further comprising a display device (142), wherein the controller (140) is further arranged to: Based on at least some of the acquired data, controlling (S2103) the display device (142) to display a first graph (1700) indicating how the subject's ability to see the optical stimulus is distributed over at least a portion of the retina of the eye (160); and Based on at least some of the generated ORG data (150) and the position of the second partition of the retina where at least some of the ORG data is generated, control (S2104) the display device (142) to display a second graph (1800) for comparison with the first graph (1700), wherein the second graph (1800) indicates how the response of the retina to optical stimulation indicated by at least some of the generated ORG data (150) is distributed over at least a portion of the retina of the eye (160).

14. The FD-OCT device (100) according to claim 11 or claim 13, wherein: The controller (140) is further arranged to compare the data of the first map (1400, 1700) with the data of the second map (1500, 1800) and to identify, based on the comparison, at least one of: one or more first regions (1601) of at least a portion of a visual field, indicating that the subject is able to see an optical stimulus in the one or more first regions (1601) of at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provide a physiological response to the optical stimulus that satisfies a predetermined condition; one or more second regions (1602, 1603) of at least a portion of the visual field, indicating that the subject is unable to see the optical stimulus in the one or more second regions (1602, 1603) of at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provide a physiological response to the optical stimulus that satisfies the predetermined condition; one or more third areas (1604) of at least a portion of the visual field, indicating that the subject is able to see an optical stimulus in the one or more third areas (1604) of at least a portion of the visual field, and indicating that one or more corresponding areas of the retina provide a physiological response to the optical stimulus that does not satisfy the predetermined condition; or one or more fourth areas (1605, 1606, 1607) of at least a portion of the visual field, indicating that the subject is unable to see the optical stimulus in the one or more fourth areas of at least a portion of the visual field, and indicating that one or more corresponding areas of the retina (1605, 1606, 1607) provide a physiological response to the optical stimulus that does not meet the predetermined condition.

15. A method of acquiring optical retinal imaging (ORG) data (150) indicative of a physiological response of a retina of an eye (160) to an optical stimulus, the method comprising: Acquiring (S51) an indicator (141) of a target position on the retina to which the optical stimulus is to be applied; applying the optical stimulus to a first subarea of ​​the retina located at the target location using (S52) the acquired indicator (141) while the gaze direction of the eye remains fixed; acquiring (S53) OCT data (135) of a second subarea of ​​the retina, wherein at least a portion of the second subarea of ​​the retina is arranged relative to the first subarea so as to be stimulated by the applied optical stimulus during acquisition of at least some of the OCT data (135); and The ORG data (150) is generated (S54) based on the acquired OCT data (135).

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