Fourier-domain oct apparatus for optoretinography

Abstract

To provide a Fourier-domain optical coherence tomography (OCT) imaging system for acquiring optoretinography (ORG) data that is indicative of a physiological response of a retina.SOLUTION: A Fourier-domain optical coherence tomography (OCT) apparatus 100 for acquiring optoretinography data 150 comprises: an optical system 120 which applies an optical stimulus to a retina of an eye; an OCT imaging system 130 which acquires OCT data from the retina; and a controller 140. The controller is configured to control the OCT imaging system to: acquire OCT data of a plurality of portions of the retina such that, for each portion, at least some of the OCT data from the portion is acquired after a respective optical stimulus has been applied to the portion; generate, based on the OCT data, respective optoretinography (ORG) data for each portion which indicates the response of the portion to the optical stimulus; and store the respective ORG data generated for each portion in association with a respective position in a visual field of the eye that is optically conjugate with a position of the portion on the retina.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] Exemplary aspects herein relate generally to the field of optical coherence tomography (OCT) imaging systems, and more particularly to a Fourier domain OCT imaging system for acquiring opto-retinography (ORG) data indicative of the physiological response of a subject's retina to light stimuli. [Background technology]

[0002] Optical coherence tomography (OCT) is an imaging technique based on low-coherence interferometry that is widely used for obtaining high-resolution 2D and 3D images of light-scattering media such as biological tissue.

[0003] Depending on the depth ranging technique, 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 imaging system's interferometer is changed over time while the OCT imaging system acquires a reflectance profile of the scattering medium being imaged (referred to herein as the "imaged object"). The reflectance profile is commonly called a "depth scan" or "axial scan" (A-scan). In FD-OCT, the spectral interference image resulting from the interference between the light in the reference arm and the light in the sample arm of the interferometer at each A-scan position is Fourier transformed to simultaneously acquire all points in the depth direction of the A-scan without changing the optical path length of the reference arm. FD-OCT allows for much faster imaging than scanning the sample arm mirror of the interferometer because all back reflections from the sample are simultaneously measured. 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 illuminates the imaged object with many wavelengths and all wavelengths are measured simultaneously using a spectrometer as a detector. In SS-OCT (also called time-encoded frequency-domain OCT), a light source is swept through a range of wavelengths and the temporal output of the detector is converted to spectral interference.

[0004] OCT imaging systems are classified as point-scanning (also called "point detection" or "scanning point"), line-scanning, or full-field, depending on how the imaging system acquires OCT data at locations on the imaged object. Point-scanning OCT imaging systems acquire OCT data by scanning a focused sample beam across the surface of the imaged object, typically along a line (which may be straight or curved, e.g., in a circle or spiral), or along a series of (usually substantially parallel) lines on the surface of the imaged object, and acquiring axial depth profiles (A-scans) for each of a number of points along the line, one at a time. The OCT data is then constructed as a one- or two-dimensional array of A-scans that represent a two-dimensional (i.e., B-scan) or three-dimensional (i.e., C-scan or volume scan) reflectance profile of the sample.

[0005] Line-scanning OCT imaging systems acquire OCT data by scanning a focused line of light across the surface of an imaged object. The measured reflectance from the imaged object is used to generate OCT data that includes a two-dimensional reflectance profile of the sample (i.e., B-scan). By scanning the focused line of light across multiple locations on the imaged object, OCT data that includes a three-dimensional reflectance profile of the sample (i.e., C-scan or volume scan) can be acquired. Typically, the focused line of light is straight and scanned in a direction perpendicular to it; however, in some cases, it may be curved and the scan direction adjusted accordingly. Full-field OCT imaging systems project a light beam onto the imaged object to acquire OT data that includes a three-dimensional reflectance profile of the sample (i.e., C-scan, or volume scan).

[0006] OCT imaging systems can be classified as phase-resolved, where both the intensity and phase of light reflected from the imaged object are measured as a function of axial depth. Modern FD-OCT imaging systems often have a degree of phase stability that allows them to function as phase-resolved OCT imaging systems.

[0007] Opto-retinography (ORG) generally refers to the detection of the physiological response of the ocular retina to light stimuli (i.e., functional activity of the retina induced by light). ORG techniques involve non-invasive optical imaging of this physiological response of the retina. For example, OCT imaging systems can be used to image retinal neurons that exhibit a change in size in response to excitation by a light stimulus. This change in size has been shown to be detectable by phase-resolved OCT imaging systems and is typically detected as a change in the length of the outer segments of the retinal cone photoreceptors, measured by measuring the change in axial depth between the inner-outer segment (IS / OS) junction and the cone outer segment tip (COST) of the cone photoreceptor. Summary of the Invention

[0008] According to a first exemplary embodiment of the present specification, there is provided a Fourier domain optical coherence tomography (FD-OCT) device configured to obtain an opto-retinography (ORG) indicative of a physiological response of a retina of a subject's eye to a light stimulus, the FD-OCT device comprising an optical system operable to apply a light stimulus to the retina, an FD-OCT imaging system operable to obtain OCT data by imaging a portion of the retina, and a controller. The controller is configured to control the FD-OCT imaging system to acquire OCT data for each of the multiple portions of the retina such that at least a portion of the OCT data acquired from that portion is acquired after a respective light stimulus is applied to the portion by the optical system, generate respective ORG data for each of the multiple portions of the retina based on the acquired OCT data, the respective ORG data indicative of a respective response of the portion of the retina to the light stimulus applied to the portion of the retina by the optical system, and store, for each of the multiple portions of the retina, the respective ORG data generated for that portion in association with a respective indication of a position within the field of the eye that is an optically conjugate point to a corresponding position of that portion of the retina.

[0009] The controller is further configured to determine, for each of the plurality of points in the field of view of the sphere, a respective indication of a retinal location of each of the plurality of portions of the retina for which OCT data is acquired by the FD-OCT imaging system, by determining, for each of the plurality of points in the field of view of the sphere, a respective indication of a corresponding location on the retina that is optically conjugate to the point. Alternatively, the controller may be further configured to determine, based on an image of the retina of the eye, a respective indication of a retinal location of each of the plurality of portions of the retina for which OCT data is acquired by the FD-OCT imaging system, and to determine, for each of the plurality of portions of the retina, a respective indication of a location in the field of view of the eye of a point that is optically conjugate to the location of the portion on the retina.

[0010] The FD-OCT device may further comprise a display device, and the controller may be further configured to: acquire data indicative of how measurements of the subject's ability to see light stimuli at different locations on the retina of the eye are distributed over at least a portion of the visual field of the eye; control the display device to display a first map indicative of how the subject's ability to see the light stimuli is distributed over at least a portion of the visual field of the eye based on at least a portion of the acquired data; and control the display device to display a second map indicative of how a physiological response of the retina to the light stimuli indicated by at least a portion of the stored ORG data is distributed over at least a portion of the visual field of the eye based on at least a portion of the stored ORG data and associated stored instruction information, in comparison to the first map.

[0011] According to a second exemplary embodiment of the present disclosure, there is provided a Fourier Domain Optical Coherence Tomography (FD-OCT) device configured to acquire opto-retinography (ORG) data indicative of a physiological response of a retina of a subject's eye to a light stimulus, the FD-OCT device comprising an optical system operable to apply a light stimulus to the retina, an FD-OCT imaging system operable to acquire OCT data by imaging a portion of the retina, and a controller. The controller is configured to control the FD-OCT imaging system to acquire OCT data for each of a plurality of portions of the retina such that at least a portion of the OCT data acquired from the portion is acquired after a respective light stimulus is applied to the portion by the optical system, generate respective ORG data for each of the plurality of portions of the retina based on the acquired OCT data indicative of a respective response of the portion of the retina to the light stimulus applied to the portion of the retina, and store, for each of the plurality of portions of the retina, the respective ORG data generated from the OCT data acquired from the portion in association with a respective indication of the position of the portion on the retina, and acquire data indicative of how measurements of the subject's ability to see light stimuli localized to respective different portions of the retina of the eye at respective different positions of the retina are distributed across at least a portion of the visual field of the eye. The controller can be configured to obtain data indicative of how measurements of the subject's ability to see light stimuli applied to different locations on the retina of the eye are distributed across at least a portion of the visual field of the eye by receiving visual field test data obtained from the eye by a visual field testing device, the visual field test data including measurements of the subject's ability to see light stimuli applied from a plurality of points in the visual field of the subject's eye, and determining, for each of the plurality of points in the visual field of the eye, respective indications of corresponding points on the retina that are optically conjugate to that point.Alternatively, the controller is configured to obtain data indicative of how measurements of the subject's ability to see light stimuli applied to different locations of the retina of the eye are distributed over at least a portion of the visual field of the eye by receiving indications provided by the subject regarding whether the subject saw each of the light stimuli applied to each of the multiple portions of the retina by the optical system and associating each of the received indications with a respective indication of the location of the respective portion on the retina. In either case, the FD-OCT device further comprises a display device, and the controller is further configured to control the display device to display a first map indicative of how the subject's ability to see light stimuli is distributed over at least a portion of the retina of the eye based on at least a portion of the obtained data, and to control the display device to display a second map indicative of how the retinal response to the light stimuli as indicated by at least a portion of the generated ORG data is distributed over at least a portion of the eye for comparison with the first map based on at least a portion of the generated ORG data and a retinal location of a second portion of the retina from which at least a portion of the ORG data was generated.

[0012] The controller can be further configured to compare data of the first map with data of the second map and, based on the comparison, identify at least one of: one or more first regions of at least a portion of the visual field indicating that the subject can view the visual field testing light stimulus within one or more first regions of at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provided a physiological response to the light stimulus that meets a predetermined condition; one or more second regions of at least a portion of the visual field indicating that the subject cannot view the light stimulus within one or more second regions of at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provided a physiological response to the light stimulus that meets a predetermined condition; one or more third regions of at least a portion of the visual field indicating that the subject can view the visual field testing light stimulus within one or more third regions of at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provided a physiological response to the light stimulus that does not meet a predetermined condition; and one or more fourth regions of at least a portion of the visual field indicating that the subject cannot view the light stimulus within one or more fourth regions of at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provided a physiological response to the light stimulus that does not meet a predetermined condition.

[0013] The FD-OCT procedure of the exemplary embodiment may further include a fixation target for fixing the gaze direction of the eye. The optical system is operable to apply a light stimulus to the retina such that illumination of the retina by the light stimulus is localized to a portion of the retina, and the optical system is controllable by the controller to vary the location on the retina where the light stimulus is applied, and includes a light source configured to generate light providing the light stimulus, and one or more scanning elements configured to direct the light to the retina. In this exemplary embodiment, the controller is further configured to obtain an indication of a target location on the retina where the light stimulus is applied by the optical system, and to control the one or more scanning elements of the optical system using the obtained indication to direct the light to a first portion of the retina at the target location while the location of the fixation target relative to the eye is fixed, and to control the FD-OCT imaging system to obtain OCT data of a second portion of the retina, where at least a portion of the second portion of the retina is positioned relative to the first portion such that the second portion of the retina can receive stimulation from the applied light stimulus during acquisition of at least a portion of the OCT data, and to generate ORG data based on the obtained OCT data of the second portion of the retina.

[0014] In an exemplary embodiment of the FD-OCT apparatus, the FD-OCT imaging system may further include an interferometer having a sample arm and a reference arm, and a detector configured to detect interference between the sample OCT light propagating along the sample arm after being scattered from the retina and the reference OCT light propagating along the reference arm, wherein at least one of the one or more scanning elements is further configured to direct the sample OCT light toward a second portion of the retina and direct the sample OCT light scattered from the second portion of the retina toward the detector.

[0015] Alternatively, the FD-OCT imaging system may include an interferometer having a sample arm and a reference arm, one or more scanning elements, and a detector configured to detect interference between the sample OCT light propagating along the sample arm after being scattered from the retina and the reference OCT light propagating along the reference arm. Further, the one or more scanning elements may be configured to direct the sample OCT light to a second portion of the retina and direct the sample OCT light scattered from the second portion of the retina to the detector. In this alternative, 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. Furthermore, the controller may be configured to use the acquired indicia 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 keeping the position of the fixation target fixed relative to the eye.

[0016] Each first portion of the retina may be smaller than an area of ​​the retina that the FD-OCT imaging system can navigate for OCT data acquisition.

[0017] According to a third exemplary aspect of the present specification, there is provided a computer-implemented method for controlling a Fourier Domain Optical Coherence Tomography (FD-OCT) device to obtain an opto-retinography (ORG) indicative of a physiological response of a retina of a subject's eye to a light stimulus, the FD-OCT device comprising an optical system operable to apply a light stimulus to the retina and an FD-OCT imaging system operable to obtain OCT data by imaging a portion of the retina. The method includes controlling the FD-OCT imaging system to acquire OCT data for each of a plurality of portions of the retina such that at least a portion of the OCT data acquired from the portion is acquired after a respective light stimulus is applied to the portion by the optical system; generating, for each of the plurality of portions of the retina based on the acquired OCT data, respective ORG data indicative of a respective response of the portion of the retina to the light stimulus applied to the portion of the retina by the optical system; and storing, for each of the plurality of portions of the retina, the respective ORG data generated for the portion in association with a respective indication of a position within the field of the eye that is optically conjugate to a corresponding position of the portion of the retina.

[0018] According to a fourth exemplary embodiment herein, there is provided a computer-implemented method for controlling a Fourier Domain Optical Coherence Tomography (FD-OCT) device to obtain an opto-retinogram (ORG) indicative of a physiological response of a retina of a subject's eye to a light stimulus, the FD-OCT device including an optical system operable to apply a light stimulus to the retina and an FD-OCT imaging system operable to obtain OCT data by imaging a portion of the retina. The method includes controlling the FD-OCT imaging system to acquire OCT data for each of a plurality of portions of the retina such that at least a portion of OCT data acquired from the portion is acquired by the optical system after a respective light stimulus is applied to the portion; generating, for each of the plurality of portions of the retina based on the acquired OCT data, respective ORG data indicative of a respective response of the portion of the retina to the light stimulus applied to the portion of the retina; storing, for each of the plurality of portions of the retina, respective ORG data generated from the OCT data acquired from the portion in association with a respective indication of a location of the portion on the retina; and acquiring data indicative of how measurements of a subject's ability to see light stimuli localized to respective different portions of the retina of the eye at respective different locations of the retina are distributed across at least a portion of a visual field of the eye.

[0019] According to a fifth exemplary embodiment of the present specification, there is provided a computer program comprising computer-readable instructions that, when executed by a computer, causes the computer to perform a method according to at least one of the third and fourth exemplary embodiments described above. The computer program may be stored in a non-transitory computer-readable storage medium or carried by a signal, for example.

[0020] Exemplary embodiments of the invention will now be described in detail, by way of non-limiting example only, with reference to the accompanying drawings, in which: Like reference symbols appearing in different drawings may represent identical or functionally similar elements, unless otherwise stated, in which: [Brief description of the drawings]

[0021] [Figure 1] 1 is a schematic diagram of an FD-OCT device 100 according to an example embodiment herein. [Diagram 2] FIG. 2 is a schematic front view of a display device 200 of the FD-OCT device 100, showing a figure 210 as an example of a fixation target for fixing the gaze direction of the eyeball. [Figure 3A] 3 is a schematic diagram of an optical system 300 and an FD-OCT imaging system 320 according to an example embodiment herein. [Figure 3B] 3B is a schematic diagram of an example optical system 330 and an example FD-OCT imaging system 331, which share an example scanning system 332 that includes lens-based optics instead of the curved mirrors 313, 315 in FIG. 3A. [Figure 3C] 3 is a schematic diagram of an optical system 340 and an FD-OCT imaging system 341 according to an alternative implementation of the exemplary embodiments herein. [Figure 3D] 3C. FIG. 3C is a schematic diagram of an example optical system 350 and an example FD-OCT imaging system 351, which share an example scanning system 352 that includes lens-based optics instead of the curved mirrors 313, 315 in FIG. 3C. [Figure 3E] 3 is a schematic diagram of an optical system 360 and an FD-OCT imaging system 361 according to a further alternative implementation of the exemplary embodiment. [Figure 3F] 3E is a schematic diagram of an example optical system 370 and an example FD-OCT imaging system 371, which share an example scanning system 372 that uses a two-dimensional scanner 373 in place of the third scanning element 363 and the fourth scanning element 364 in FIG. 3E. [Figure 4] FIG. 1 is a schematic diagram of programmable signal processing hardware that can be configured to perform the functions of the controller 140 described herein. [Diagram 5] 1 is a flow diagram illustrating a process by which the controller 140 generates the ORG data 150, according to example embodiments herein. [Figure 6A]6 is a schematic diagram of an example of a first portion and a second portion of a retina during the performance of process S52 and process S53 of FIG. 5 using the optical system 300 and the FD-OCT imaging system 320 of the exemplary embodiment. [Figure 6B] 6 is a schematic diagram of an example of a first portion and a second portion of a retina during the performance of process S52 and process S53 of FIG. 5 using the optical system 300 and the FD-OCT imaging system 320 of the exemplary embodiment. [Figure 6C] 6 is a schematic diagram of an example of a first portion and a second portion of a retina during the performance of process S52 and process S53 of FIG. 5 using the optical system 300 and the FD-OCT imaging system 320 of the exemplary embodiment. [Figure 6D] 6E is a schematic diagram of an example of a first portion and a second portion of a retina during the performance of process S52 and process S53 of FIG. 5 using optical system 360 and FD-OCT imaging system 361 of FIG. 6E. [Figure 6E] 6E is a schematic diagram of an example of a first portion and a second portion of a retina during the performance of process S52 and process S53 of FIG. 5 using optical system 360 and FD-OCT imaging system 361 of FIG. 6E. [Figure 6F] 5A and 5B are schematic diagrams of first and second parts of the implementation of process S52 and process S53 of FIG. 5 using optical system 340 and FD-OCT imaging system 341 of FIG. 3C. [Figure 7] FIG. 13 is a flow diagram illustrating the process by which the controller 140 generates ORG data 150 for multiple locations on the retina. [Figure 8A] 8 shows a plurality of first sub-examples 801-807 and a plurality of second sub-examples 811-817 during execution of processes S72 and S73 of FIG. 7 during an ORG data imaging session. [Figure 8B] 8 shows a plurality of first sub-examples 821-824 and a plurality of second sub-examples 825-824 during execution of processes S72 and S73 of FIG. 7 during an ORG data imaging session. [Figure 8C]8 shows a plurality of first sub-examples 831-834 and a plurality of second sub-examples 835-838 during execution of processes S72 and S73 of FIG. 7 during an ORG data imaging session. [Figure 8D] 8 shows a plurality of first sub-examples 841-844 and a plurality of second sub-examples 845-848 during execution of processes S72 and S73 of FIG. 7 during an ORG data imaging session. [Figure 8E] 8 illustrates a number of first sub-examples 851, 852, 855, 856 and a number of second sub-examples 853, 854, 857, 858 during execution of processes S72 and S73 of FIG. 7 during an ORG data imaging session. [Figure 9] 9 illustrates an exemplary first portion 901 and an exemplary second portion 902 during execution of processes S52 and S53 of FIG. 5 or processes S72 and S73 of FIG. 7 during an ORG data imaging session. [Figure 10] 10 illustrates an exemplary first portion 1001 and an exemplary second portion 1002 during execution of processes S52 and S53 of FIG. 5 or processes S72 and S73 of FIG. 7 during an ORG data imaging session. [Figure 11] FIG. 11 is a flow diagram illustrating a process by which the controller 140 of an exemplary embodiment can determine an indication of a target location on the retina to which a light stimulus should be applied based on a point in the field of view of the eye. [Figure 12] FIG. 13 is a flow diagram illustrating a process by which the controller 140 can select indices and corresponding locations for which OCT data is to be acquired, and map the locations on the retina from which the OCT data was acquired to corresponding locations in the visual field of the eye. [Figure 13] FIG. 13 is a schematic diagram of a data structure 1300 stored by the controller 140, in which individual ORG data generated for each portion of a plurality of separate portions of the retina are stored in association with respective position coordinates within the field of the eye of a point optically conjugate to the position of that portion. [Figure 14]FIG. 1 is a flow diagram illustrating a process by which a controller 140 obtains data indicative of how measurements of a subject's visual performance in response to light stimuli applied to different locations on the retina of the eye are distributed across at least a portion of the visual field of the eye, and controls a map display 142 to display a map as described herein. [Figure 15] FIG. 15 is a flow diagram showing a process in which the controller 140 acquires data in process S1401 of FIG. [Figure 16] FIG. 14 shows a first example map 1400 that can be displayed by the map display device 142 in process S1402 of FIG. [Figure 17] FIG. 15 is a diagram showing a second example map 1500 that can be displayed by the map display device 142 in process S1403 of FIG. [Figure 18] FIG. 16 is a diagram showing a third example map 1600 that can be displayed by the map display device 142 in process S1405 of FIG. [Figure 19] FIG. 11 is a flow diagram showing a process by which the controller 140 obtains data indicative of how measurements of a subject's visual ability in response to light stimuli applied to different locations on the retina of the eye 160 are distributed across at least a portion of the retina of the eye 160, and controls the map display device 142 to display the fourth and fifth maps described herein. [Figure 20A] 20 is a flow diagram showing a process in which the controller 140 acquires data in process S2102 of FIG. 19. [Figure 20B] 20 is a flow diagram illustrating an alternative process by which the controller 140 obtains data in process S2102 of FIG. 19. [Figure 21] FIG. 20 is a diagram showing a fourth example map 1700 that can be displayed by the map display device 142 in process S2103 of FIG. [Figure 22] FIG. 20 is a diagram showing a fifth example map 1800 that can be displayed by the map display device 142 in process S2104 of FIG. [Diagram 23]FIG. 1 is a flow diagram illustrating a computer-implemented method for controlling an FD-OCT device for ORG data acquisition, according to an example embodiment. [Figure 24] FIG. 11 is a flow diagram illustrating a computer-implemented method for controlling an FD-OCT device for ORG data acquisition, according to another example embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Visual field testing is widely used to determine the extent of the eye's visual field and its functions within the visual field. Visual field testing relies on the subject indicating (often by pressing a button or verbally) that they can see a light stimulus presented to them from a position within the visual field of the eye under test. Perimetry is a type of visual field testing in which the visual field of the eye is measured systematically. Many different perimetry techniques are known, such as automated static perimetry, Goldmann perimetry, microperimetry, etc.

[0023] Such visual field tests are based on the output of the entire visual pathway of the eye, i.e., the collective function of the visual pathway that results in the subject's perception of whether or not the presented light stimulus is visible. It is therefore difficult or impossible to attribute to a specific intermediary in the visual pathway of the eye the inability of the subject to see a light stimulus applied in the visual field of the eye recorded in the visual field test. This in turn limits both the scope and the accuracy of making clinically useful diagnoses. Previous efforts to fill this void in physiological information about the visual pathway have tended to focus on microperimetry, which displays visual field data on a retinal image to facilitate correlation of functional abnormalities with structural features on the retina. However, this relies on the interpretation of structural features on the retinal surface and does not provide a definitive indication of retinal function at a given point in the eye.

[0024] In consideration of the above problems, the inventors have devised a Fourier domain optical coherence tomography (FD-OCT) device configured to acquire optoretinograpy (ORG) data and store the data in association with an indication of the position in the visual field of the eye of a point that is optically conjugate with the corresponding position of the OCT data used to generate the ORG data. As a result, the ORG data can be displayed side-by-side with visual field test data acquired, for example, by a perimetry device. The inventors have also devised a FD-OCT device configured to acquire data (e.g., data acquired by a microperimeter) indicative of the distribution of the subject's ability to recognize light stimuli in a portion of the retina, and further data derived from the acquired ORG data and indicative of the distribution of the retinal response to light stimuli in that portion of the retina for comparison.

[0025] Thus, the ORG data can be used to provide complementary information, such as from visual field testing, regarding the functionality of the photoreceptors of the eye that constitute a part of the visual pathway of the subject. This information allows the physician to quickly and easily obtain useful insight into the possible causes of vision loss (or visual impairment) in the area of ​​the visual field or retina of the eye identified by the visual field test results. This information allows the physician to quickly and accurately identify areas of the visual field or retina of the eye where vision loss or visual impairment due to abnormal photoreceptor function can be excluded with a reasonable degree of certainty. This information further allows the identification of false positives in visual field testing (e.g., when the subject indicates that they can see a light stimulus, but no confirmatory retinal response is observed) and the confirmation of negative results, thereby improving the accuracy of the visual field test data.

[0026] Exemplary embodiments of the above-mentioned FD-OCT imaging device will now be described in more detail with reference to the accompanying drawings.

[0027] 1 is a schematic diagram of an FD-OCT device 100 configured to acquire opto-retinography (ORG) data 150 indicative of a physiological response of a subject's retina 160 to a light stimulus, according to an exemplary embodiment. The FD-OCT device 100 includes a fixation target 110, an optical system 120, an FD-OCT imaging system 130, a controller 140, and, optionally, a map display device 142.

[0028] The fixation target 110 is positioned to fixate the gaze direction 161 of the eye 160 (i.e., the direction along the visual axis of the eye 160 and outward from the eye 160). This fixation can occur when the eye 160 fixates the fixation target 110. That is, the fixation target 110 is positioned to be visible by the eye 160 such that the gaze direction 161 of the eye 160 can be fixed when gazed at by the eye 160 during acquisition of the ORG data 150. However, the fixation target 110 can alternatively be positioned to fixate the gaze direction 161 of the eye 160 when the patient's other eye is fixed on the fixation target 110. In the majority of subjects without strabismus, the muscles controlling eye movement act in unison to direct both eyes in the same direction. Fixing the gaze direction of one eye by the fixation target 110 also results in the same gaze direction of the other eye (even if the other eye cannot see the fixation target 110). For example, if the eye 160 is the right eye of the subject, the gaze direction 161 of the eye 160 can be fixed by fixing the left eye on the fixation target 110. The position of the fixation target 110 relative to the eye 160 can be controlled by the controller 140, as in this exemplary embodiment, to control the gaze direction 161 of the eye 160 when the eye 160 is fixed on the fixation target 110. However, the position of the fixation target 110 may alternatively be set to a fixed position relative to the expected position of the eye 160 (i.e., the position where the eye 160 is located relative to the FD-OCT imaging system 130 so that the FD-OCT imaging system 130 acquires AS-OCT images) during manufacturing or installation / commissioning of the FD-OCT imaging system 130. The fixation target 110 can be incorporated into the FD-OCT device 100 so as to be visible to the eye 160 in a variety of ways known to those skilled in the art or as described in U.S. Pat. No. 11,253,146 (B2), which is incorporated herein by reference in its entirety.

[0029] FIG. 2 is a schematic diagram of an implementation of a fixation target 110 in the form of a figure 210 displayed by a display device 200 constituting a part of the FD-OCT device 100. The display position of the figure 210 relative to the eye 160 is controllable by the controller 140, such that the gaze direction 161 of the eye 160 is controlled when the eye 160 is fixed on the figure 210. In other words, the position of the eye 160 is fixed relative to the FD-OCT imaging system 130 (e.g. by placing the patient's chin on the chin rest of the FD-OCT imaging system 130). The display position of the figure 210 on the display area of ​​the display device 200 is then adjustable as indicated by the arrows in FIG. 2, such that the gaze direction 161 of the eye 160 can be set (steered) when the eye 160 is fixed on the figure 210. In FIG. 2, the figure 210 is in the form of a point, but it should be understood that the shape of the figure is not limited thereto, but may instead be a cross, a circle, or any shape towards which the eye 160 can be fixed.

[0030] Furthermore, the fixation target 110 can be implemented in a form other than a graphic displayed on the display device 200. For example, the fixation target 110 can be a light source (e.g., a light-emitting diode) attached to an actuator, which can be controlled by the controller 140, and when the eyeball 160 is fixed to the light source, the light source can be moved relative to the eyeball 160 to control the gaze direction 161 of the eyeball 160.

[0031] The optical system 120 is capable of applying a light stimulus to the retina of the eye 160 such that illumination of the retina by the light stimulus is localized to (and possibly spans or fills) a portion of the retina. The optical system 120 is controllable to vary the location on the retina of the eye 160 to which the light stimulus is applied, while the gaze direction of the eye 160 remains fixed by the fixation target 110. In other words, the optical system 120 is controllable to apply the light stimulus to each of a plurality of different portions of the retina of the eye 160, such that when the light stimulus is applied to one portion of the plurality of portions of the retina of the eye 160, the light stimulus is not applied to any of the other portions of the plurality of portions of the retina. As described in more detail below, the optical system 120 is controllable to vary the location on the retina to which the light stimulus is applied, while the position of the fixation target 110 remains fixed relative to the eye 160 (the gaze direction 161 of the eye 160 remains fixed to the fixation target 110).

[0032] The light stimulus may be, as in this exemplary embodiment, a flash of light of a predetermined duration that is applied to the retina of the eye 160 along the optical path 121 of the optical system 120. The duration of the flash of light is typically much shorter than the length of time that OCT data is acquired by the FD-OCT imaging system 130 to generate the ORG data 150, and depends on the intensity of the stimulus. The duration of the flash of light may be, for example, between 5 ms and 50 ms. The duration of the light stimulus is controllable by the controller 140, as described in more detail below.

[0033] The FD-OCT imaging system 130 (which may be a phase-stable FD-OCT imaging system) may be a point-scanning FD-OCT imaging system as in this exemplary embodiment. However, the FD-OCT imaging system 130 may take other forms, such as a line-scanning or full-field FD-OCT imaging system. The FD-OCT imaging system 130 is operable to acquire complex OCT data 135 by imaging a portion of the retina of the eye 160. The OCT data 135 may include a time sequence of OCT images, such as a time sequence of A-scans, B-scans, or C-scans as in this exemplary embodiment.

[0034] 3A is a schematic diagram of an optical system 300 and an FD-OCT imaging system 320, which may form an exemplary implementation of the optical system 120 and the FD-OCT imaging system 130 of FIG. 1 as in this exemplary embodiment. 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. The scanning system 310 is shared by both the optical system 300 and the FD-OCT imaging system 320 as described below, 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. For clarity, a fixation target is not shown in FIG. 3A, but a fixation target may be located within the scanning system 310, at least to one side of the first curved mirror 313, above and / or below the plane of the drawing, as described in U.S. Pat. No. 11,253,146 (B2). Light from the fixation target can thus reach the eye 160 via the second scanning element 314 and then the second curved mirror 315 .

[0035] The OCT light source 321 of the FD-OCT imaging system 320 emits an OCT beam L b The OCT light source 321 can include an illumination light source and an illumination light source aperture as in this exemplary embodiment. In this case, the illumination light source can emit light through the source aperture to generate the OCT beam L. bThe shape and size of the illumination source aperture (e.g., diameter if the source aperture is circular) are configured to generate the OCT beam L b can be defined (i.e., such that the size and shape are the same). The illumination light source can be a swept illumination light source configured to generate light having a wavelength swept across a range of wavelengths during scanning by the FD-OCT imaging system 320 if the FD-OCT imaging system 320 is a swept-source OCT (SS-OCT) imaging system, or a broadband light source configured to generate light having a range of wavelengths (i.e., broad spectral content) simultaneously during scanning by the SD-OCT imaging system if the FD-OCT imaging system 320 is a spectral-domain OCT (SD-OCT) imaging system. The illumination light source can be any known swept or broadband light source (as the case may be). For example, the illumination light source can comprise a laser or a light-emitting diode.

[0036] The OCT light source 321 may include additional components, such as one or more collimating lenses for collimating the light from the light source. Moreover, as will be readily understood by those skilled in the art, the OCT light source 321 may alternatively take other forms when the FD-OCT imaging system 320 is a line-field or full-field FD-OCT imaging system. For example, when the FD-OCT imaging system 320 is a line-field FD-OCT imaging system, the OCT light source 321 may be configured to generate linear light and may include a laser and one or more cylindrical lenses (e.g., a combination of plano-concave and plano-convex lenses configured to focus the beam from the laser in respective orthogonal directions to form a linear light). However, any other type of spatial light modulator for beam shaping known to those skilled in the art may alternatively be used.

[0037] The interferometer 322 detects the OCT beam L from the OCT light source 321. b Split the sample OCT light oand the reference OCT light L r The interferometer 322 is further configured to transmit light L scattered by a portion of the retina of the eye 160 and collected by the scanning system 310 along a reference arm 325 of the interferometer 322 as a reflected light L. c Receives the reference OCT light L r and the collected light L c The interference light L I and the interference light L I to the detector 323. In other words, the reference OCT light L propagating through the reference arm 325 r and collected light L scattered by a portion of the retina of the eye 160 and collected by the scanning system 310 during a scan performed by the FD-OCT imaging system 320. c and are guided to interfere with each other in unison, resulting in interference light L I is directed to and received by detector 323.

[0038] As in this exemplary embodiment, the interferometer 322 splits the OCT beam Lb using a beam splitter 326 to propagate through a sample arm 324 and a reference arm 325 of the interferometer 322, and outputs the reference OCT light Lb reflected by a reference mirror 327. r The collected light L from the scanning system 310 c The interferometer 322 may be a Michelson interferometer that interferes with the OCT beam L. Although a Michelson interferometer has been described, those skilled in the art will appreciate that the interferometer 322 is not limited thereto, and any interferometer suitable for OCT, such as, for example, a Mach-Zehnder interferometer, may be used. Furthermore, those skilled in the art will appreciate that the interferometer 322 may also be appropriately adapted when the FD-OCT imaging system 320 is a line-scanning or full-field FD-OCT imaging system. For example, if the FD-OCT imaging system 320 is a line-scanning FD-OCT imaging system, the interferometer 322 may be a free-space interferometer that uses at least one beam splitter. Furthermore, the interferometer 322 is not limited to being a free-space interferometer, and may instead be an interferometer using optical fibers. In this case, the interferometer uses a fiber coupler to couple the OCT beam Lb is split and propagates through the sample arm and the reference arm of the interferometer 322, and the reference light L r and collected light L c It is possible to interfere with the

[0039] The scanning system 310 scans the sample OCT light L across the retinal portion of the eye 160. o A point scan (e.g., one-dimensional or two-dimensional) of the eyeball 160 is performed, and light L scattered by the retina portion of the eyeball 160 during the point scan is measured. c The scanning system 310 is therefore configured to adjust the scanning position to collect the sample OCT light L. o 160. The light L scattered from the retina of the eyeball 160 at each scan position is measured. c , to acquire A-scans at each scan location distributed (e.g., in one or two dimensions) across a portion of the retina of the eye 160. By acquiring successive A-scans, the scanning system 310 can acquire B-scans and / or C-scans of the retina of the eye 160.

[0040] Sample OCT light L o The sample OCT light L enters the scanning system 310 from the interferometer 322 and propagates to the beam splitter 311. o The light L scattered by the retina of the eye 160 and collected by the scanning system 310 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 enters the retina of the eye 160. c is the sample OCT light L o 3, travels the same optical path through the scanning system 310 as in FIG. 3, but in the reverse order, propagates through the beam splitter 311, and then exits the scanning system 310.

[0041] The point scan is performed by the scanning system 310 rotating about a first axis (not shown) to scan the sample OCT light L. o a first scanning element 312 for scanning the sample OCT light L across the retina portion of the eye 160 in a first direction or opposite to the first direction;o and a second scanning element 314 that scans the sample OCT light L across the retinal portion of the eye 160 in a second direction or opposite to the second direction. The second direction may be orthogonal to the first direction, as in this exemplary embodiment. Thus, by rotating the first scanning element 312 and the second scanning element 314, the sample OCT light L can be directed to any location of the retinal portion of the eye 160 that is within the field of view of the FD-OCT device 100. o As described above, the rotation of the first scanning element 312 and the second scanning element 314 is coordinated by the controller 140 or a dedicated scanning system controller (not shown) to steer the sample OCT light L. o can be scanned over a portion of the retina of the eye 160 according to a predefined scan pattern. The predefined scan pattern can be any suitable scan pattern known to a person skilled in the art, such as, for example, a unidirectional scan (where a set of parallel scan lines extend according to a common direction), a circular scan, a serpentine scan, or a spiral scan, which may be predefined or selected by a user of the FD-OCT device 100 at the time of manufacture.

[0042] The first curved mirror 313 and the second curved mirror 315 may be elliptical mirrors each having a first focus and a conjugate second focus, as in this exemplary embodiment. The first scanning element 312 is located at a first focus FP1 of the first curved mirror 313, and the second scanning element 314 is located at a second focus FP2 of the first curved mirror 313. The second scanning element 314 is also located at a first focus FP3 of the second curved mirror 315, and the eye 160 is in the vicinity of a second focus FP4 of the second curved mirror 315. More specifically, the pupil of the eye 160 is located at the second focus FP4 of the second curved mirror 315 such that the optical path of the scanning system 310 is steerable in two dimensions across the retinal region of the eye 160. However, the first curved mirror 313 and the second curved mirror 315 may be any reflective component having an aspheric reflective surface, such as a conic section shape such as a parabola or hyperbola, or more generally, may have a shape described by one or more two-variable polynomial functions.

[0043] The use of curved mirrors in scanning system 310 allows FD-OCT imaging system 130 to function as a wide-field FD-OCT imaging system, or an ultra-wide-field (UWF) FD-OCT imaging system, as described in further detail in WO 2014 / 53824 (A1), the contents of which are incorporated herein by reference in their entirety, although scanning system 310 is not so limited.

[0044] FIG. 3B is a schematic diagram of an alternative implementation of an exemplary optical system 330 and an exemplary FD-OCT imaging system 331, which share a lens-based scanning system 332 (where like reference numbers indicate the same elements as in FIG. 3A). As shown in FIG. 3B, instead of being guided by curved mirrors 313, 315, light is directed from the first scanning element 312 to the second scanning element 314, and then through a beam splitter 333 and a lens barrel 334 of one or more lenses to the retina of the eye 160. The beam splitter 333 may be the same shape as the beam splitter 311 (e.g., a beam splitter cube or a dichroic mirror). Additionally, the scanning system 332 may include a first lens relay and a second lens relay (which may be of equal focal length) between the first scanning element 312 and the second scanning element 314 (as the only intervening optics). A fixation target 335 may be provided as an example of the fixation target 110 of FIG. 1. Light from fixation target 335 passes through beam splitter 333 , lens relay 334 and onto eye 160 .

[0045] First scanning element 312 and second scanning element 314 may each be a galvanometer optical scanner ("H-galvo" and "V-galvo", respectively) as in this exemplary embodiment, although other types of scanning elements may alternatively be used, such as a MEMS scanning mirror or a resonant scanning mirror.

[0046] The detector 323 detects the interference light L I That is, the detector 323 is disposed to detect the interference light L I and the received light L I Based on the interference line, the detection signal Sd The detector 323 is configured to generate an interference light L I The detection signal S d The specific form of the detector 323 depends on the form in which the FD-OCT imaging system 320 is implemented. For example, if the FD-OCT imaging system 320 is implemented as an SD-OCT imaging system, the detector 322 comprises a spectrometer that may have a diffraction grating, a Fourier transform lens, and a detector array (or a line scan camera). If the FD-OCT imaging system 320 is implemented as an SS-OCT imaging system, the photodetector 120 may comprise a balanced photodetector configuration including two photodetectors (e.g., reverse biased photodiodes) whose output photocurrents are subtracted from each other and the differential current signal is converted to a voltage detection signal by a transimpedance amplifier. The detection signal S d can be processed by OCT data processing hardware of the FD-OCT imaging system 320 to generate OCT data 135, as in this exemplary embodiment, although the functionality of the OCT data processing hardware may alternatively be performed by the controller 140 (i.e., the detection signal S d may be received and processed by controller 140 to generate OCT data 135).

[0047] If the FD-OCT imaging system 320 is a line scanning system rather than a point scanning system, the OCT light source 321 generates a line of light as described above. In such a case, the interferometer 322 detects the OCT beam L b Instead, the line light is split into sample OCT light as a sample OCT line light. The scanning system 310 performs a line scan of the sample OCT line light across the retinal portion of the eye 160 and detects the light L scattered by the retinal portion of the eye 160 during the line scan. c3. The scanning system 310 may thus further comprise a lens arranged to focus the sample OCT line of light at a first focal point FP1 of the first scanning element 312. The sample OCT line of light is then sequentially reflected by the first scanning element 312, the first curved mirror 313, the second scanning element 314 and the second curved mirror 315 to the retina of the eye 160. The light scattered at the retina of the eye 160 is then returned to the detector 323 via the scanning system 310 (i.e. adapted for line scanning) in a manner similar to that described above for the point scanning implementation. The sample OCT line of light is thus steered in two dimensions within the eye by the rotation of the first scanning element 312 and the second scanning element 314, allowing the scanning of the eye 160 to be performed by the scanning system 310 coordinated by the controller 140 or a dedicated steering system controller. However, because the sample OCT line light is incident on the retina, rather than acquiring at least one A-scan as in a point scanning implementation, the scanning system 310 acquires at least one B-scan (e.g., successive B-scans forming a C-scan) of the retina of the eye 160.

[0048] The light source 301 of the optical system 300 emits light L S The light L S may be, as in this exemplary embodiment, one or more wavelengths in the visible spectrum for the human eye, but more generally any wavelength for stimulating a physiological response of the retina of the eye 160. The light source 301 may be configured to generate a number of different wavelengths of light, each of which may be used as a desired light stimulus (e.g., by using a broadband spectrum light source generating white light, filtered with at least one adjustable or removable spectral filter). However, this is not intended to limit the scope of the present invention, and may be modified in any way to suit the particular application. S This may alternatively be achieved by optical system 300 comprising additional light sources configured to generate light of different wavelengths that can provide optical stimulation in addition to the wavelength of interest (these light sources can be combined into a single output of light source 301 using fiber couplers, wavelength division multiplexing (WDM) fibers, beam splitters, or dichroic mirrors).

[0049] Furthermore, the light source 301 is controlled by the controller 140 to emit light L having a desired light intensity. S It is possible to generate

[0050] The light source 301, as in this exemplary embodiment, can include an illumination light source (e.g., a light emitting diode) and an illumination light source aperture, similar to those previously described for the OCT light source 321. The light source 301 can include additional components, such as, for example, one or more collimating lenses for collimating the light from the light source. The controller 140 controls the light source 301 of the optical system 300 to emit light L as a light stimulus, as described below. S Furthermore, the light source 301 can be controlled to vary the duration of the light stimulus applied by the light source 301.

[0051] Beam splitter 311 may be a cube beam splitter as in this exemplary embodiment, but may alternatively be, for example, a dichroic mirror.

[0052] The optical system 300 shares the scanning system 310 used by the FD-OCT imaging system 320 to perform point scanning. It uses a beam splitter 311 to split the light L S The optical path of the sample OCT light L o This is accomplished by coupling the light L generated by the light source 301 and traveling through the scanning system 310, although any other suitable configuration for combining the two light paths may be used. S The optical path of the sample OCT light L travels through the scanning system 310. o can be combined with the first and second optical paths by beam splitter 311, and the optical paths can travel along a common axis, although the optical paths can alternatively travel along axes offset by a predetermined amount (e.g., by adjusting the incidence position of one optical path on beam splitter 311).

[0053] The scanning system 310 thus detects the light L S The light L is further configured to be directed toward the retina of the eye 160. S The light enters the scanning system 310 via a beam splitter 311 and is then reflected successively by a first scanning element 312, a first curved mirror 313, a second scanning element 314, and a second curved mirror 315 before being incident on the retina of the eye 160.

[0054] Sample OCT light L o As in the case of the optical system, the light L S The location on the retina of the eye 160 where the light L is illuminated can be controlled to vary by a first scanning element 312 that rotates about a first axis (not shown) to move the light path of the scanning system 310 in a first direction or opposite to the first direction across the retina of the eye 160, and a second scanning element 314 that rotates about a second axis 316 to move the light path of the scanning system 310 in a second direction or opposite to the second direction across the retina of the eye 160. By rotating the first scanning element 312 and the second scanning element 314, the light L S The light path traveled by the light L is steered in two dimensions. S can be irradiated to any point on the retina of the eyeball 160. Therefore, the light L generated by the light source 301 S By controlling the timing and duration of the scanning, and the range and speed of rotation of the first scanning element 312 and / or the second scanning element 314, the controller 140 can focus any point on the retina of the eye 160 with light L for a desired duration. S This duration is the time it takes for the light L generated by the light source 301 to be stimulated. S The light intensity can be controlled by the controller 140 to expose the retina of the eye 160 to the light to a predetermined degree. For example, the degree of exposure can be between 10% and 66%. Higher values ​​of exposure may be favorable for the study of alpha waves (i.e., fast retinal response) in the ORG data 150.

[0055] By optical system 300 sharing scanning system 310 with FD-OCT imaging system 320, the entire field of view of FD-OCT imaging system 320 can be accessed by optical system 300 without additional scanning hardware. This reduces the complexity of FD-OCT device 100 and may facilitate integration of FD-OCT imaging system 320 into a complex sample arm, such as in the UWF FD-OCT imaging system described above.

[0056] 3C is a schematic diagram of an optical system 340 and an FD-OCT imaging system 341 (like reference numbers indicate the same elements as in FIG. 3A) that can form an implementation of the optical system 120 and the FD-OCT imaging system 130 of FIG. 1 according to an alternative implementation of the present exemplary embodiment. The optical system 340 and the FD-OCT imaging system 341 are the same as the optical system 300 and the FD-OCT imaging system 320, respectively, of FIG. 3A, but differ from these components of FIG. 3A by sharing a scanning system 342 rather than the scanning system 310. The scanning system 342 is the same as the scanning system 310, except that it includes a third scanning element 343 and a beam splitter 344. The third scanning element 343 can be implemented in the same manner as the first scanning element 312, but is used by the scanning system 342 (instead of the first scanning element 312) to split the light L from the light source 301. S is directed to the retina of the eyeball 160, and light L S The beam splitter 344 can be implemented in the same form as the beam splitter 311, and the light L from the light source 301 is changed in position on the retina of the eyeball 160 in a first direction and a direction opposite to the first direction. S is directed to the first curved mirror 313, and the sample OCT scan L o to the first curved mirror 313 (and the collected light L c3A ) to the first scanning element 312. For clarity, a fixation target is not shown in Fig. 3A, but the fixation target may be located in the scanning system 310 on at least one side of the first curved mirror 313, i.e. above and / or below the plane of the drawing, as described in US Patent No. 11,253,146 (B2). Light from the fixation target can then reach the eye 160 via the second scanning element 314 and then the second curved mirror 315.

[0057] The scanning system 342 detects the light S The third scanning element 343, which is used to direct the light L generated by the light source 301 and traveling through the scanning system 310, is distinct from the first scanning element 312 and may be independently controlled by the controller 140. S The optical path of the sample OCT light L o can be varied in a first direction (or opposite to the first direction) independently of the optical path that the light L takes through the scanning system 310. S The optical path traveled by the sample OCT light L through the scanning system 310 is o 3A and 3B . This is at the expense of increasing the complexity of the FD-OCT device 100, but adds an additional degree of freedom to the variation of the light stimulus on the retina of the eye 160, as compared to the implementation of FIG. 3A and FIG. 3B. For example, this degree of freedom can be achieved by changing the light L S The optical path of the sample OCT beam L o Removing at least some of the coupling of the optical pathways in the retina can be advantageous in studying the pathways of photoreceptor cells within the retina (e.g., to introduce a spatial misalignment between the center of the first part of the retina and the center of the second part of the retina).

[0058] The exemplary embodiment of Figure 3C includes curved mirrors 313, 315, which may be omitted as shown in Figure 3D, which is a schematic diagram of an exemplary optical system 350 and an exemplary FD-OCT imaging system 351 sharing a scanning system 352 (where like reference numbers indicate the same elements as in Figures 3A-3C) with the curved mirrors 313, 315 omitted. As shown in Figure 3D, light is directed from the first scanning element 312 and the third scanning element 343 to the second scanning element 314 via a first lens relay 353 and a second lens relay 354 (which may have equal focal lengths) located between the third scanning element 343 and the second scanning element 314. In an alternative exemplary embodiment, the first lens relay 353 and the second lens relay 354 may be optional, and the only optical components interposed 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 the beam splitter 344. As shown in Figure 3D, a fixation target 335 may be provided in the scanning system 352 of Figure 3D, similar to the scanning system 332 of Figure 3B.

[0059] 3E is a schematic diagram of optical system 360 and FD-OCT imaging system 361, which constitute further alternative implementations of optical system 120 and FD-OCT imaging system 130 of the exemplary implementations. Optical system 360 differs from optical system 300 of FIG. 3A, and FD-OCT imaging system 361 differs from FD-OCT imaging system 320 of FIG. 3A only by sharing scanning system 362 (rather than scanning system 310). Scanning system 362 is similar to scanning system 332 of FIG. 3B, e.g., by including one or more lenses in lens barrel 334 instead of curved mirrors 313, 315 of FIG. 3A, but differs from scanning system 332 by further including third scanning element 363, fourth scanning element 364, and beam splitter 365 instead of beam splitters 311, 333 of FIG. 3B. The third scanning element 363 can be implemented in the same manner as the first scanning element 312, and the fourth scanning element 364 can be implemented in the same manner as the second scanning element 314, but the third scanning element 363 and the fourth scanning element 364 are used by the scanning system 362 (in place of the first scanning element 312 and the second scanning element 314) to direct the light L S The light L is directed toward the retina of the eye 160. S The position on the retina of the eye 160 where the light is irradiated is changed in a first direction, a direction opposite to the first direction, a second direction, and a direction opposite to the second direction. The scanning system 362 may further 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 further 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 direct the light from the fourth scanning element 364 to the eye 160 after passing through the lens barrel 334.

[0060] The scanning system 362 may further include a beam splitter 366 and a fixation target 335 as described above in connection with Figure 3B. Light from the fixation target 335 may be directed by the beam splitter 366 through the beam splitter 365 and the lens relay 334 to the eye 160.

[0061] Light L to the retina of the eyeball 160 S The third scanning element 363 and the fourth scanning element 364 used in the scanning system 362 to direct the sample OCT light L o Unlike the first scanning element 312 and the second scanning element 314 used in the scanning system 362 to direct light L toward the retina, the scanning elements 363, 364 are controllable by the controller 140 independently of the scanning elements 312, 314. Thus, when generated by the light source 301, the light L S The optical path traveled by the sample OCT light L through the scanning system 362 is o Independently of the optical path traveled by the light L, the light L can be changed in a first direction (or a direction opposite to the first direction) and a second direction (or a direction opposite to the second direction). S The optical path traveled by the sample OCT light L through the scanning system 362 is o 3A and 3D , but at the expense of increased complexity of the FD-OCT device 100 compared to the implementation described in Figures 3A and 3D , allows for independent control of the change in light stimulation on the retina of the eye 160 in two degrees of freedom.

[0062] Scanning system 362 includes a third scanning element 363 and a fourth scanning element 364, although these could alternatively be replaced by a single two-dimensional scanner, such as a micro-electromechanical systems (MEMS) scanner.

[0063] 3F is a schematic diagram of an example optical system 370 and an example FD-OCT imaging system 371, which share a scanning system 372 that includes a two-dimensional scanner 373. In FIG. 3F, elements that are the same as in FIG. 3A-3E are similarly numbered. Scanning system 372 is similar to 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). This is because the light L S The light L is directed toward the retina of the eye 160. Sis used to change the position on the retina of the eye 160 to be illuminated in a first direction, a direction opposite to the first direction, a second direction, and a direction opposite to the second direction.

[0064] The scanning system 372 may further include a beam splitter 366 and a fixation target 335 as described above in connection with Figure 3B. Light from the fixation target 335 may be directed by the beam splitter 366 through the beam splitter 365 and lens relay 334 to the eye 160.

[0065] As a further alternative to the exemplary implementation, the optical system 120 may be configured to control the light L on the retina by the controller 140. S The spatial light modulator may comprise a spatial light modulator capable of controlling the illumination position of the collimated light L generated by the light source 301. For example, the spatial light modulator may comprise 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)). It is configured to be illuminated by collimated light and is controllable by the controller 140, and the collimated light L generated by the light source 301 is illuminated by the collimated light L. SIt is possible to change the position on the retina where the light from the light source 301 is incident by passing only through a predetermined portion of the dynamic amplitude mask. When the dynamic amplitude mask is provided in the form of a DMD, the DMD can include an array of rotatable micromirrors, each of which can be individually switched by the controller 140 from one of the first and second different orientations to the other of the first and second orientations. More specifically, the DMD can be configured to set each micromirror in the DMD to either a first direction that reflects the light from the light source 301 in the direction of the eyeball 160 or a second direction that reflects the incident light so as to deviate from the eyeball 160 and prevent the light from the light source 301 from reaching the eyeball 160. In this way, the use of the DMD enables binary amplitude modulation of the light received at the position of each micromirror on the DMD. However, it should be noted that the function of the dynamic amplitude mask can be provided by other suitable spatial light modulators other than the DMD, such as an array of liquid crystal cells, an analog micromirror array, etc. For example, in an exemplary alternative embodiment where the dynamic amplitude mask includes liquid crystal cells, the liquid crystal in each liquid crystal cell forming the array can 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 transmits the incident light L S towards the eyeball 160. On the other hand, the liquid crystal cell in the second liquid crystal phase blocks the incident light L S to prevent transmission to the eyeball 160. Further, it is also possible that the portion not covered by the mask of the dynamic amplitude mask consists of an array of liquid crystal cells having a liquid crystal in the first phase, and the masked portion of the dynamic amplitude mask consists of an array of liquid crystal cells having a liquid crystal in the second phase. As a further example, the spatial light modulator may consist of an array of light sources (e.g., LEDs) configured to provide corresponding spatially separated collimated light beams, and it may be possible to control the position on the retina where the light stimulus is applied by controlling it with the controller 140.

[0066] Furthermore, as an 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 position on the retina of the eyeball 160 irradiated with the light L S .

[0067] The configuration described above for varying the location on the retina where the light stimulus is applied is similar to that of a single sample OCT beam L. o to the retina of the eye 160, it should be noted that the disclosure is not so limited and these configurations for varying the location on the retina at which the light stimuli are applied may also be used in a multi-beam FD-OCT imaging system configured to deliver multiple sample OCT beams to the retina simultaneously.

[0068] The above configurations allow the location of the light stimulus on the retina to be set with much greater precision than would be possible by maneuvering the eye, e.g., moving the fixation target 110 laterally relative to the eye 160 (i.e., within the field of view of the eye 160). Furthermore, holding the fixation target 110 in a fixed position during ORG data 150 acquisition improves patient comfort and improves ease of use of the system. Furthermore, some of the above configurations for varying the location of the light stimulus on the retina utilize the existing optics of the OCT sample arm, thus facilitating integration of the optical system 120 into existing OCT systems.

[0069] Returning to FIG. 1 , the controller 140 is configured to obtain at least one indication 141 of a target location on the retina to which the light stimulus is applied by the optical system 120, and to control the optical system 120 with the obtained indication 141 to apply the light stimulus to a first portion of the retina at the target location while keeping the position of the fixation target 110 fixed relative to the eye 160. The controller 140 is further configured to control the FD-OCT imaging system 130 to obtain OCT data 135 of a second portion of the retina, where at least a portion of the second portion of the retina is positioned relative to the first portion and can be stimulated by the applied light stimulus when obtaining at least a portion of the OCT data 135. The controller 140 is further configured to generate ORG data 150 based on the obtained OCT data 135, as described in more detail below.

[0070] The controller 140 (and a dedicated scanning system controller, if present) can be provided in any suitable form, for example as a programmable piece of processing hardware 400 as shown generally in FIG. 4. The programmable signal processor 400 processes the OCT data 135 (or the detection signal S d), and possibly also to receive the indices 141, output control signals to the FD-OCT imaging system 130, and output to a map display device 142 (such as a computer screen) for displaying the ORG data 150 and / or graphs thereof. The signal processing hardware 400 further comprises a processor 420 (e.g., a central processing unit CPU, and / or a graphic processing unit GPU), a working memory 430 (e.g., a random access memory), and an instruction store 440 for storing a computer program 445 of computer readable instructions, which, when executed by the processor 420, cause the processor 420 to perform various functions, including the functions of the controller 140 described herein. The working memory 430 stores information used by the processor 420 while executing the computer program 445. The instruction store 440 may consist of a ROM (e.g., in the form of an electrically erasable programmable read only memory (EEPROM) or flash memory) on which the computer readable instructions are pre-stored. Alternatively, the instruction storage 440 may comprise a RAM or similar type of memory, and the computer readable instructions for the computer program 445 may be input thereto from a computer program product, such as a non-transitory computer readable storage medium 450 in the form of a CD-ROM, DVD-ROM, etc., or from 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 as described herein.In other words, the controller 140 of an exemplary embodiment may include a computer processor 420 and a memory 440 storing computer-readable instructions that, when executed by the computer processor 420, cause the computer processor 420 to obtain an indication 141 of a target location on the retina to which a light stimulus is applied by the optical system 120, use the obtained indication 141 to control the optical system 120 to apply a light stimulus to a first portion of the retina that is the target location while keeping the position of the fixation target 110 fixed relative to the eyeball 160, control the FD-OCT imaging system 130 to obtain OCT data 135 of a second portion of the retina, at least a portion of which is positioned relative to the first portion and is stimulated by the light stimulus applied when acquiring at least a portion of the OCT data 135, and generate ORG data 150 based on the obtained OCT data 135 as described herein.

[0071] It should be noted, however, that controller 140 may be implemented with non-programmable hardware, such as an ASIC, FPGA, or other integrated circuit dedicated to performing the functions of controller 140 described above, or a combination of such non-programmable hardware and programmable hardware as described with reference to FIG. 4. Furthermore, while controller 140 has been described in the context of a single programmable signal processing hardware 400, controller 140 is not so limited, and its functions may be divided into multiple programmable signal processing hardware as shown in FIG. 4, or parts thereof, and / or non-programmable hardware as described above. For example, controller 140 may be implemented with programmable signal processing hardware as shown in FIG. 4 and configured to obtain an indication 141 of a target location on the retina of a light stimulus provided by optical system 120, use the obtained indication to control optical system 120 to provide a light stimulus to a first portion of the retina at the target location while maintaining a fixed position of fixation target 110 relative to eyeball 160, and control FD-OCT imaging system 130 to obtain OCT data 135 of a second portion of the retina. Here, at least a portion of the second portion of the retina is positioned relative to the first portion to be stimulated by a light stimulus provided during acquisition of at least a portion of the OCT data 135, as described herein. In this case, a separate processor (e.g., similar to processor 420 of FIG. 4) may be arranged to receive the acquired OCT data 135 from controller 140 and generate ORG data 150 based on the acquired OCT data 135 (and output the ORG data 150, for example, to map display 142), as described herein.

[0072] The map display 142 may be configured to receive data from the controller 140 for display to a user (e.g., a physician), as in this exemplary embodiment. The communication interface 410 may then be configured to receive input from a user of the FD-OCT device 100, as requested by the controller 140. For example, the map display 142 may receive and display the ORG data 150 or a graphical representation thereof, and may be controlled by the controller 140 to display a map, as described below. Input from the user of the FD-OCT device 100 may include, for example, the indicia 141, or an indication of a second portion of the retina, as discussed below, which the map display 142 may transmit to the controller 140. The map display 142 may be, for example, an LCD screen, and may include programmable signal processing hardware 400, as shown diagrammatically in FIG. 4, which may be used to generate a graphical representation of the ORG data 150, process input provided by the user (e.g., by processing touch input from the user if the map display 142 is a touch screen), and interface with the controller 140. However, the map display 142 is optional and may be omitted. For example, the aforementioned functionality of the map display 142 may be provided by an external computer, or in some cases, the ORG data 150 may not need to be displayed, but instead may be stored on an external server or within the memory of the controller 140 for later retrieval.

[0073] 5 is a flow diagram illustrating a process by which the controller 140 may generate the ORG data 150 as in this exemplary embodiment. The process defines an ORG imaging session that is initiated by a dark adaptation period of the retina of the eye 160. For example, the FD-OCT device 100 may be configured such that no light (either internal or external to the FD-OCT device 100) is incident on the retina of the eye 160 for a predetermined time (e.g., about 5 minutes). Or, more simply, the patient may be instructed to close their eyes or wait in a dark room for the predetermined time.

[0074] 5, the controller 140 obtains an indicator 141 of a target position on the retina of the eye 160 to which a light stimulus is 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 that is to be the center position of the light stimulus applied by the optical system 120. The indicator 141 of the target position can be automatically generated based on a predetermined position on the retina defined relative to one or more anatomical landmarks (e.g., the optic disc, the macula, etc.) and taking into account the gaze direction 161 of the eye 160. The target location indicator 141 may alternatively be selected by a user and input into the controller 140 a target location on a retinal image (e.g., a frontal OCT image previously acquired by the FD-OCT imaging system 130, or a retinal reflectance image previously acquired using a scanning laser ophthalmoscope (SLO) included in the FD-OCT imaging device 100 and which may share a scanning system 310 with the FD-OCT imaging system 130) displayed on the map display device 142 (or an external display device such as a computer screen) using a mouse and / or keyboard, or by one or more touch operations, for example if the display is a touch screen.

[0075] 5, while the position of the fixation target 110 relative to the eye 160 remains fixed and the eye 160 is fixed on the fixation target 110 (i.e., while the position of the fixation target 110 in the field of view (FoV) of the eye 160 remains fixed, where the FoV encompasses everything that can be seen when the head is in a fixed orientation and the eye 160 rotates in its socket), the controller 140 uses the acquired indicator 141 to control the optical system 120 to apply a light stimulus to a first portion of the retina of the eye 160 at a target position. The controller 140 uses the acquired indicator 141 to control the optical system 120 to apply a light stimulus to a first portion of the retina at a target position, while the position of the fixation target 110 relative to the eye 160 remains fixed. The controller 140 is configured to translate the retinal locations indicated by the indicia 141 into a set of one or more corresponding control parameters for steering the optical system 120 to apply light stimuli to substantially the same retinal locations as indicated by the indicia 141. This can be accomplished in one of several different ways. For example, the controller 140 can use a mapping between retinal locations and corresponding values ​​of the control parameters. This can be provided, for example, in the form of a look-up table (LUT) or a function defined by the parameter set. The mapping can be determined by calibration using techniques well known to those skilled in the art.

[0076] In this exemplary embodiment, the controller 140 controls the scanning system 310 to rotate the first scanning element 312 and the second scanning element 314 to adjust the light L traveling through the scanning system 310, as shown in FIG. S The controller 140 controls the light source 301 to project the light L onto the target position. Sto be propagated along the optical path either after, or possibly during, said rotation. The first portion of the retina may be smaller than the field of view of the FD-OCT imaging system 13, as in this exemplary embodiment (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 portion of the retina are shown and described in more detail below.

[0077] 5, the controller 140 controls the FD-OCT imaging system 130 to acquire OCT data 135 of a second portion of the retina of the eye 160. In a scanner similar to that described for the indicia 141 in process S51, the controller 140 can acquire a second indicia indicative of the position of the second portion of the retina of the eye 160 by a user selecting a position of the second portion of the retina on the map display 142. Alternatively, the second indicia can be generated by the controller 140 based on at least one of the indicia 141 or the first portion of the retina of the eye 160, as described in more detail below. The second portion may have a fixed, e.g. predetermined, positional relationship to the first portion.

[0078] The acquisition of the OCT data 135 may, as in this exemplary embodiment, relate to temporally consecutive OCT images of a second portion of the retina of the eye 160 within a first time period (i.e. the time period between the acquisition time of a first OCT image in the time sequence of OCT images and the acquisition time of a last OCT image in the time sequence of OCT images). Thus, in this exemplary embodiment shown in FIG. 3A , 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 the second portion of the retina of the eye 160 according to a predefined scanning pattern to acquire a time sequence of OCT images. The controller 140 may alternatively instruct a dedicated scanning system controller (if present) to control one or both of the scanning elements 312, 314.

[0079] At least a part of the second portion of the retina of the eye 160 is arranged with respect to the first portion such that it is stimulated (or at least partially illuminated) by the applied light stimulus during acquisition of at least a part of the OCT data 135. That is, during execution of the process S53 for the second portion of the retina, the controller 140 executes the previous process S52 and controls the optical system 120 using the acquired index 141 to apply a light stimulus to the corresponding first portion of the retina of the eye 160 at a first time within a first period of time. Then, at least a part of the OCT images of the time sequence of OCT images are acquired after the first time. In each of these OCT images, at least a part of the second portion of the retina of the eye 160 is stimulated (or at least partially illuminated) by the applied light stimulus. The second portion of the retina can at least partially overlap with the corresponding first portion of the retina. Or, alternatively, spaced apart but sufficiently close to the corresponding first portion such that light incident on the first portion can be scattered into at least a portion of the second portion or otherwise applied light stimulation to at least a portion of the second portion of the retina to stimulate a retinal region therein. Examples of positions of the second portion of the retina of the eye 160 relative to the corresponding first portion of the retina of the eye 160 are described in more detail below.

[0080] In one variation of the exemplary embodiment, the controller 140 first obtains an indication of the location of the second portion of the retina where the OCT data 135 is to be acquired, as described above, and then generates the indicia 141 such that the first portion of the retina, which is the target location, can stimulate at least a portion of the second portion of the retina (i.e., such that the ORG data 150 can be generated at the location of the second portion of the retina). For example, the location of the first portion can be selected to be along a predetermined scanning pattern used to acquire the OCT data 135. Thus, for example, the same rotation of one or both of the first scanning element 312 and the second scanning element 314 of FIG. 3A or FIG. 3B, or the second scanning element 314 of FIG. 3C or FIG. 3D, can be used for both acquiring the OCT data 135 and applying the light stimulus to the first portion of the retina. This allows the light stimulus to be applied to the eye 160 in a shorter time window than if the controller 140 had to adjust for different rotations of the scanning elements in processes S52 and S53. This becomes important when the temporal sequence of OCT images obtained in process S53 are closer in time (as is desired for reducing motion artifacts in the OCT images). Note that this advantage can also be achieved (albeit at the cost of increased system complexity) when the position of the first portion is not along a predetermined retinal scan pattern, but is outside the scan pattern using configurations such as those described above with reference to Figures 3C-F.

[0081] 5, in process S54, controller 140 generates ORG data 150 based on acquired OCT data 135. As in the present exemplary embodiment, controller 140 can generate ORG data 150 based on phase information of acquired OCT data 135. ORG data 150 generated by controller 140 can be displayed to a user on map display 142 or output to an external computer or server, for example, for analysis.

[0082] The controller 140 can generate the 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 technique described in Kari V. Vienola et al., "Velocity-based optoretinography for clinical applications," Optica 9, 1100-1108, 2022, the entire contents of which are incorporated herein by reference. Briefly, the velocity-based ORG technique is generated based on the acquired OCT data (which in this case consists of a temporal sequence of B-scans) by first flattening each B-scan to bring the photoreceptor inner / outer segment (IS / OS) and cone outer segment (COST) reflections to the same height in each A-scan in the respective B-scan. A moving time window (e.g., 10 ms) is then used to select a group of (e.g., five) consecutive B-scans that are motion-corrected relative to the first B-scan in the series. The phase data cube for each complex data cube for each spatial coordinate in the volume is then unfolded in the time dimension to minimize the magnitude of the phase difference between the data cubes of successive phase B-scans. After unfolding, a least squares linear fit in time is used to calculate the rate of phase change for each coordinate pair to calculate the instantaneous velocity for each spatial location. These instantaneous velocities and B-scan amplitudes are laterally averaged, if necessary, to obtain instantaneous depth-dependent measurements of velocity and backscatter, respectively. By shifting the time window (10 ms), a time series of depth profiles is constructed for each of the velocity and reflectivity. Both of these can be visualized in time-depth coordinates as M-scans. The velocities of the IS / OS and COST layers are then extracted. Their difference is the velocity of OS contraction / elongation in that region as a function of time. This constitutes the ORG data 150 (or alternatively, the OS length response may be the 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 COST layers.Alternatively, the magnitude of so-called "alpha waves" (i.e., fast retinal responses, typically on a time scale of a few milliseconds) in the data of the contraction / elongation velocity of the outer segment (OS) as a function of time can be determined and stored as (or part of) the ORG data 150. Additionally or alternatively, the magnitude of so-called "beta waves" (i.e., slow responses, typically on a time scale of a few seconds) can be determined and stored as (or part of) the ORG data 150. As a further alternative, the ORG data 150 can include a value (e.g., a predefined scale of 1 to 10) representing the quality of the retinal response at the location of the second portion of the retina, generated by comparing the retinal response represented by the acquired ORG data with a healthy retinal response. The healthy retinal response can be obtained, for example, from ORG data at a location of the retina of the eye 160 that the physician has assessed as healthy, or from the ORG data of a sample healthy eye.

[0083] The controller 140 can generate the ORG data 150 based on the acquired OCT data 135 using intensity-based ORG techniques, such as the OCT brightness change technique and OCT band analysis technique described in Kim TH, Ma G, Son T, Yao X, “Functional Optical Coherence Tomography for Intrinsic Signal Optoretinography: Recent Developments and Deployment Challenges,” Front. Med. 9:864824, (2022), the contents of which are incorporated herein by reference in their entirety. The OCT brightness change technique can be used to detect local changes in pixel brightness values ​​caused by light stimulation on the retina. Data processing techniques used in OCT brightness change analysis techniques may include aligning raw OCT B-scans to correct for eye movements, normalizing pixel intensities based on inner retinal intensity to limit the effects of pupil response, identifying "active" intrinsic optical signal (IOS) pixels (i.e., pixels that show significant intensity changes after light stimulation, which may be positive for increased intensity and negative for 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 of the retina). When intensity-based ORG techniques are used, the OCT data may be acquired by an OCT imaging system that is not phase stable.

[0084] 6A, 6B, and 6C are schematic diagrams of an example of a first portion of the retina of eye 160 in processes S52 and S53 above, and a corresponding second portion of the retina of eye 160, respectively, illuminated by optical system 300 and imaged by FD-OCT imaging system 320 according to an exemplary embodiment. These figures show a retinal region 600 of eye 160 that corresponds to the field of view of FD-OCT imaging system 130. That is, the second portion of eye 160 (where OCT data 135 is acquired) is illuminated by scanning system 310 with sample OCT light L. oSince the optical system 300 shares the scanning system 310 with the FD-OCT imaging system 320, the first portion of the eye 160 may also be located at a position where the scanning system 300 can direct the light L. S The light L may be directed to any location within the area 600. S It should be noted that the light beams L may be generated by the light source 301 as light beams of different diameters, so that each first portion may have a different size (width) as shown in each of Figures 6A, 6B, and 6C. S Different beam sizes (eg, diameters) can be achieved, for example, by using different illumination source apertures.

[0085] In particular, when the optical system 300 shares the scanning system 310 with the FD-OCT imaging system 320, the light beam (light L generated by the light source 301) S The radius of the light beam (as ) can be set to illuminate the entire second portion of the eye 160 while the light beam is at each scan position within the second portion of the eye 160. For example, if the second portion is a linear portion corresponding to a linear B-scan, the radius of the light beam can be set to illuminate the entire linear portion when the light beam is at the first scan position (corresponding to the first A-scan of the linear B-scan) and each subsequent scan position. This configuration prevents "flicker" perceived by parts of the retina as the light beam moves between scan positions, resulting in alternately illuminated and unilluminated parts of the retina, and may improve the quality of the ORG data generated.

[0086] 6A shows a circular first portion 610 as an example of a first portion of the retina in process S52, and a second portion 611 corresponding to an A-scan as an example of a second portion of the retina in process S53. The controller 140 controls the FD-OCT imaging system 320 to rotate the first scanning element 312 and the second scanning element 314 of the scanning system 310 to a first pair of respective angular positions so that each A-scan is acquired at the position of the second portion 611. Then, the process S53 of acquiring OCT data 135, which is a time sequence of A-scans of the second portion 611, begins. At the first time, the controller 140 controls the optical system 300 using the acquired index 141 to acquire light L from the light source 301. S (The diameter of the circular first portion is determined by the amount of light L incident on the retina.) S Because the circular first portion 610 is concentric with the second portion 611, the first scanning element 312 and the second scanning element 314 remain in their respective angular positions in the first pair during acquisition of the ORG data 150, thereby simplifying this process.

[0087] 6B shows a first portion 620 of a hollow circle as an example of the first portion of the retina in process S52, and a second portion 621 corresponding to a circular B-scan as an example of the second portion of the retina in process S53 of FIG. 5. In this case, the controller 140 controls the FD-OCT imaging system 320 to start process S53 to acquire OCT data 135. This is a time sequence of circular B-scans of the second portion 621, and rotates the first scanning element 312 and the second scanning element 314 of the scanning system 310 to perform a two-dimensional point scan using a circular scanning pattern, such that each of the circular B-scans is the second portion 621. At the first time, the controller 140 executes process S52 and controls the optical system 300 using the acquired indices 141 to capture light L. S While the light source 301 is generating the light stimulus, the first scanning element 312 and the second scanning element 314 of the scanning system 314 are rotated to apply the light stimulus to the hollow circular first portion 620 (the thickness of the hollow circular first portion 620 is determined by the thickness of the light L incident on the retina).S (The diameter of the hollow circular first portion 620 and second portion 621 follow the same scanning pattern, so that the same rotation of the first scanning element 312 and the second scanning element 314 (as coordinated by the controller 140) can be used to apply light stimuli and acquire OCT data 135. This simplifies the operation of the FD-OCT device 100.

[0088] 6C shows a linear first portion 630 as an example of the first portion of the retina in process S52, and a linear second portion 631 corresponding to a linear B-scan as an example of the second portion of the retina in process S53 of FIG 5. Controller 140 performs processes S51 to S53 of FIG 5 in a similar manner as described above in FIG 6B, except that the predefined scan pattern is a unidirectional scan along a single scan axis (for a single linear B-scan) (the thickness of linear first portion 630 is proportional to the thickness of light L incident on the retina). S (The diameter of the straight line 630 is the diameter of the straight line 631.) Because the straight line first portion 630 and the straight line second portion 631 extend along a common straight line, the same rotation (controlled by the controller 140) of the first scanning element 312 and / or the second scanning element 314 can be used to apply the light stimulus and acquire the OCT data 135. This simplifies the operation of the FD-OCT device 100.

[0089] 6A, 6B, and 6C are described as being concentric or extending along a common line, this is not necessary and any other type of scanning pattern can be used. Furthermore, the circular first portion 610, the hollow circular first portion 620, and the linear first portion 630 may be arranged to focus the light L incident on the retina. S However, the diameter or thickness of each of the retina and the retina is different from that of the retina. S Alternatively, the diameter of the first scanning element 312 and the second scanning element 314 may be smaller than the intended width of the first portions, and the controller 140 may adjust the rotation of the first scanning element 312 and the second scanning element 314 to progressively illuminate the entirety of each first portion.

[0090] 6A, 6B, and 6C are shown to be larger than the respective second portions, this need not be the case. For example, the aperture of the illumination light source of the light source 301 may be selected to reduce the sample OCT light L o A light with a diameter smaller than that of L S or the second portion can extend outside the first portion of the eye 160 by controlling the rotation of one or both of the first scanning element 312 and the second scanning element 314 accordingly.

[0091] 6D and 6E are schematic diagrams of an exemplary first portion of the retina of eye 160 and a corresponding exemplary second portion of the retina of eye 160 within region 600, in processes S52 and S53 above, respectively, as illuminated by optical system 360 and imaged by FD-OCT imaging system 361 of FIG.

[0092] FIG. 6D shows a circular first portion 640 as an example of a first portion of the retina in process S52, and a second portion 641 corresponding to an A-scan as an example of a second portion of the retina in process S53 of FIG. 5. As shown in FIG. 6D, the second portion 641 is not concentric with the circular first portion 640. This is possible due to the independent control of the photostimulation position. In contrast to FIGS. 6A-6C, the optical system 360 is not concentric with the sample OCT beam L. o The light stimulus can be applied regardless of where on the retina the OCT is aimed, and the light stimulus can be applied to any desired part of the retina without interrupting the acquisition of a time sequence of OCT images.

[0093] Figure 6E shows a circular first portion 650 as an example of the first portion of the retina in process S52 of Figure 5, and a second portion 651 corresponding to a circular B-scan (acquired using the circular scan as the predefined scanning pattern) as an example of the second portion of the retina in process S53 of Figure 5 for the circular B-scan. These geometries are similarly achieved by independently controlling the location of application of light stimuli to the retina and the location of acquisition of OCT data from the retina.

[0094] 6F is a schematic diagram of a linear first portion 660 as an example of a first portion of the retina in process S52 of FIG. 5 and a second portion 661 corresponding to a plurality of parallel linear B-scans forming a C-scan (obtained using a raster scan as the predetermined scanning pattern) as an example of a second portion of the retina in process S53 of FIG. 5. Here, the controller 140 controls the optical system 340 to apply the light stimulus and the FD-OCT imaging system 341 to acquire the OCT data 135. In this case, the light stimulus is the sample OCT beam L o Independently of the linear B-scans, the sample OCT beam L can be controlled in a first direction perpendicular to the linear B-scans and in a direction opposite to the first direction, thereby allowing the sample OCT beam L to be directed in a second direction between the intended positions of each of the multiple parallel linear B-scans. o The use of optical system 360 and FD-OCT imaging system 361 at the expense of increased system complexity also allows for the optical stimulus to be applied to the linear first portion 660 without affecting the movement of the sample OCT beam L in a second direction between the intended positions of each of the multiple parallel linear B-scans. o It should be noted that similar C-scans can be acquired both by using optical system 300 and FD-OCT imaging system 320 at the expense of interrupting the movement of the optics.

[0095] Instead of acquiring a single index 141 for a single target location and corresponding OCT data 135 acquired for that target location, the controller 140 can acquire multiple indices, each indicative of a respective target location on the retina, and process respective OCT data at each target location on a respective second portion of the retina corresponding to a respective first portion of the retina to generate respective ORG data during an ORG imaging session.

[0096] 7 is a flow diagram illustrating a process by which the controller 140 acquires and processes respective OCT data for each second portion of the retina to generate respective ORG data indicative of a physiological response of each second portion of the retina to a light stimulus applied to a corresponding first portion of the retina. The process illustrated in FIG. 7 may be preceded by a period of dark adaptation of the retina of the eye 160 to improve the accuracy and reliability of the ORG data 150, similar to the description above with reference to FIG. 5.

[0097] 7, in process S71, controller 140 obtains a plurality of indices, each indicative of a respective target location on the retina of eye 160 to which a light stimulus is applied by optical system 120. Each of the plurality of indices is of a similar format to index 141 described above, and the plurality of indices are obtained by controller 140 in a manner similar to that described above for index 141.

[0098] In process S72 of FIG. 7, while the position of the fixation target 110 relative to the eye 160 is fixed, the controller 140 uses the acquired indices to control the optical system 120 to apply a light stimulus to each target location of each respective first portion of the retina of the eye 160. The controller 140 controls the optical system 120 using each acquired indices in turn in a manner similar to that described above with respect to the indices 141 (with reference to FIG. 5). The light stimulus applied to each first portion of the retina of the eye 160 does not stimulate any other first portion of the retina of the eye 160. That is, each of the multiple indices is for a respective target location on the retina that is different from the target locations indicated by the other indices, so that each first portion of the retina does not overlap on the retina with any other first portion. Each first portion 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). An example of a first portion of the retina is described in more detail below.

[0099] In process S73 of FIG. 7, the controller 140 controls the FD-OCT imaging system 130 to acquire, for each first portion of the retina of the eye 160, respective OCT data of a respective second portion of the retina of the eye 160. The controller 140 acquires a second indicator indicative of a location on the retina of each of the second portions of the retina and controls the FD-OCT imaging system 130 to acquire respective OCT data of the second portion of the retina of the eye 160, in a manner similar to that described above with reference to process S53 of FIG. 5. At least a portion of each respective second portion of the retina is positioned in relation to the respective first portion of the retina such that it can be stimulated by a light stimulus applied to the first portion when acquiring at least a portion of the respective OCT data. This is in a manner similar to that described with reference to process S53 of FIG. 5 for the first and second portions of the retina. Each second portion of the retina may be separated (spaced apart) from all other second portions of the retina. However, at least a portion of the second portion may overlap at least partially with at least a portion of the other second portions in some cases. Examples of positions of second portions of the retina relative to each first portion of the retina are discussed in more detail below.

[0100] In process S74 of Figure 7, the controller 140 processes the respective OCT data for each second portion of the retina to generate respective ORG data for the second portion. The ORG data indicates the physiological response of each second portion of the retina to a light stimulus applied to the corresponding first portion of the retina. Each ORG data has the same format as described for ORG data 150 of Figure 5.

[0101] It should be noted that the controller 140 may first obtain a first index of the plurality of indices 141 and use it to obtain a first OCT data corresponding to the first index, as in this exemplary embodiment. The controller 140 may then repeat this OCT data obtaining process (operation procedure) using each of the remaining indices 141 until each of the remaining indices 141 has its own OCT data obtained. The controller 140 may then process each of the OCT data to generate each of the ORG data in process S74 of FIG. 7. However, the generation of the ORG data may be performed in parallel with the acquisition of the respective OCT data. That is, after obtaining the first respective OCT data, the controller 140 may start executing process S74 to generate each of the ORG data based on the first respective OCT data while repeating the above operation procedure for each of the remaining indices 141, and generate each of the ORG data based on the respective OCT data corresponding to each of the plurality of indices in parallel with the acquisition of the OCT data. Furthermore, process S71 of FIG. 7 may be performed to obtain all of the multiple indices before performing any of processes S72, S73, S54 on a first indice of the multiple indices.

[0102] The controller 140 can execute process S72 and process S73 of Fig. 7 (for all of the multiple indices 141) after only one dark adaptation period of the retina of the eye 160 during an ORG imaging session. This is possible due to a combination of the applied light stimulus being limited to a first portion of the retina, which is smaller than the field of view of the FD-OCT imaging system 130, and the position of the light stimulus applied on the retina being changeable between multiple different positions on the retina by the optical system 120. Since the light stimulus applied to each first portion of the retina of the eye 160 does not stimulate any other first portion of the retina of the eye 160, there is no need to provide a dark adaptation period (as is required in the existing ORG technology described in the background) each time a light stimulus is applied to the retina of the eye 160. Additionally, the controller 140 can perform processes S72 and S73 (for all of the multiple indices) for acquiring ORG data for multiple retinal locations on time scales much shorter than those requiring light adaptation (e.g., periods of 0.1 seconds or less, 1 second or less, or 3 seconds or less), which are not achievable with the conventional methods described above.

[0103] It should be noted that the controller 140 first obtains second indexes for each of multiple second portions of the retina for which respective OCT data is to be obtained, and then generates multiple indexes 141 such that when a light stimulus is applied to the first portion of the retina, each of the first portions of the retina whose position on the retina is indicated by a respective one of the indexes 141 is capable of stimulating at least a portion of the second portion of the retina (i.e., such that respective ORG data can be generated based on the respective OCT data at each of the second portions).

[0104] Figures 8A-8E are schematic diagrams of an exemplary first portion of an eye 160 and an exemplary second portion of an eye 160 in processes S72 and S73 of Figure 7, which, unless otherwise indicated, are illuminated by any implementation of optical system 120 according to the exemplary embodiments (e.g., optical system 300 and FD-OCT imaging system 320) and imaged by any implementation of FD-OCT imaging system 130, respectively. These figures show a retinal region 600 of the eye 160 that corresponds to the field of view of the FD-OCT imaging system 130 shown in Figures 6A-6F.

[0105] Figure 8A shows first portions 801-807 as examples of the multiple first portions in process S72 of Figure 7 and multiple second portions 811-817 as examples of the multiple second portions in process S73 of Figure 7 in an ORG imaging session. Controller 140 executes process S72 and process S73 to stimulate the first portions in sequence for each pair of first and second portions, 801 and 811, 802 and 812, 803 and 813, etc., located at different positions on the retina, and acquire OCT data 135 from the corresponding second portions, e.g., as described above with respect to linear first and second portions 630 and 631 of Figure 6C.

[0106] Figure 8B shows first portions 821-824 as examples of the multiple first portions in process S72 of Figure 7 and multiple second portions 825-828 as examples of the multiple second portions in process S73 of Figure 7 in an ORG imaging session. Controller 140 executes process S72 and process S73 to stimulate the first portions in sequence for each pair of first and second portions, 821 and 825, 822 and 826, 823 and 827, etc., located at different locations on the retina, and acquire OCT data 135 from the corresponding second portions, e.g., as described above with respect to linear first and second portions 660 and 661 of Figure 6F.

[0107] 8C illustrates a plurality of first portions 831-834 as examples of a plurality of first portions in process S72 of FIG. 7 and a plurality of second portions 835-838 as examples of a plurality of second portions in process S73 of FIG. 7 in an ORG imaging session, which are used to perform a radial trend analysis of the eye 160 by analysis of the variation of the retinal response of the eye 160 with the eccentricity of the eye 160 (e.g. from the periphery of the eye 160 towards the fovea of ​​the eye 160). The controller 140 performs the process S72 and the process S73 of stimulating the first portions and acquiring the OCT data 135 from the corresponding second portions, as described with reference to the linear first portion 630 and the linear second portion 631 of FIG. 6C in turn for each pair of first and second portions 831 and 835, 832 and 836, 833 and 837, etc., linearly arranged at different positions on the retina.

[0108] 8D shows a plurality of first portions 841-844 as examples of a plurality of first portions in process S72 of Fig. 7 and a plurality of second portions 845-848 as examples of a plurality of second portions in process S73 of Fig. 7 in an ORG imaging session, which may also be used to perform a radial trend analysis of the eye 160 analyzing the variation of the retinal response of the eye 160 depending on the eccentricity of the eye 160. To achieve this, each of the first and second portions may form concentric ring-like regions centered on the fovea of ​​the eye 160, which correspond to different eccentricities of the eye 160. The controller 140 sequentially performs processes S72 and S73 of stimulating a first portion and acquiring OCT data 135 from the corresponding second portion as described above with reference to the hollow circular first portion 620 and second portion 621 of FIG. 6B for each pair of first and second portions positioned at different distances from the fovea, 841 and 845, 842 and 846, 843 and 847, etc.

[0109] 8E shows a plurality of first portions 851, 852, 855, 856 as examples of the plurality of first portions in process S72 of FIG. 7 and a plurality of second portions 853, 854, 857, 858 as examples of the plurality of second portions in process S73 of FIG. 7 in an ORG imaging session. The controller 140 sequentially performs process S72 and process S73 of stimulating a first portion and acquiring OCT data 135 from a corresponding second portion, as described with reference to the linear first portion 630 and second portion 631 of FIG. 6C, for each pair of first and second portions, 851 and 853, 855 and 857, etc., located at different positions on the retina. In this case, the controller 140 controls the optical system 120 to apply a first light stimulus to the first portions 851, 852 on the retina and to apply a second light stimulus to the second portions 855, 856 on the retina. Here, the first light stimulus is different from the second light stimulus (e.g., by the light source of optical system 120 emitting light at two different wavelengths, or by optical system 120 comprising two different light sources configured to emit light at different wavelengths). Although two different light stimuli have been described, optical system 120 is not so limited and may be operable to generate further different light stimuli (e.g., as described with reference to light source 301 of optical system 300 of FIG. 3A).

[0110] FIG. 9 shows a first portion 901 and a second portion 902 in the region 600, which may be examples of the first portion of process S52 of FIG. 5 and the second portion of process S53 of FIG. 5, respectively. A stimulus applied to the first portion 901 stimulates the first portion 903 of the second portion 902, but does not stimulate the second portion 904 of the second portion 902. Thus, the second portion 904 provides a baseline non-stimulated region that can be used for comparison and / or normalization purposes. This second portion partial stimulation technique (by performing a time modulation of the signal used to generate the light stimulus) can also be used in any of the other examples described with reference to FIGS. 8A-8E. Furthermore, although the technique has been described with respect to a linear first portion 630 and a linear second portion 631, the technique is not so limited and the principles described can be applied to other geometries of the first and second portions of the retina.

[0111] In some cases, it may be advantageous for the controller 140 to divide the processing of the OCT data into smaller steps to generate the ORG data 150. FIG. 10 illustrates an exemplary first portion 1001 and an exemplary second portion 1002 of the region 600, which provide examples of the first portion and second portion of the process S52 and S53 of FIG. 5, respectively, or parts of the first and second portions of the process S72 and S73 of FIG. 7, respectively. As illustrated in FIG. 10, the OCT data of the second portion 1002 can be divided into subsets of OCT data, each corresponding to a region 1003-1007, and each subset of OCT data can be processed separately using the techniques described above to generate the ORG data 150 for each portion 1003-1007 on the retina of the eye 160. For example, in the velocity-based ORG technique described above, the time sequence of partial B-scans acquired from each of the regions 1003-1007 can be used as the time sequence of B-scans for the algorithm to generate an ORG at each location of the time sequence of partial B-scans. This technique of splitting the second portion process can also be performed for at least a portion of the remaining portions (if any) of the multiple second portions. Additionally, although the technique has been shown and described in relation to a linear first portion 1001 and a linear second portion 1002, the technique is not so limited and the principles described can be applied to other geometries of the first and second portions of the retina.

[0112] The controller 140 of the FD-OCT device 100 can be used to store, for each second portion of the plurality of second portions of the retina of the eye 160 described with reference to FIG. 7, the respective ORG data generated for the second portion (the ORG data being indicative of a respective physiological response of the second portion of the retina to a light stimulus applied to a corresponding first portion of the retina) in association with an indication of a respective position of a point in the field of the eye 160 that is optically conjugate with the position of the second portion on the retina of the eye 160 (e.g. the position of a point on the second portion, such as the geometric center of the second portion). The stored ORG data and the stored associated indication can provide an indication of the retinal function of the eye 160 at a plurality of points in the field of the eye 160, which can aid in the diagnosis of various ocular pathologies. Furthermore, the stored ORG data and the stored associated indication can be used to complement the results of a visual field test of the eye 160 (e.g. an automated static perimetry test, a kinetic perimetry test or a frequency-doubled perimetry test). In particular, it may be useful in determining the cause of blind spots or reduced retinal sensitivity in the visual field of eye 160, as determined by visual field testing, as described in more detail below.

[0113] The data items correlated and stored by the controller 140 as described above can be generated in different ways. For example (as described in more detail below with reference to FIG. 11), the location of the point on the retina stimulated by the optical system 120 and from which OCT data is acquired by the FD-OCT imaging system 130 (for the generation of ORG data by the controller 140) can be selected by the controller 140 based on a predetermined location in the visual field of the eye 160. This approach can be useful when the ORG data 150 generated by the controller 140 is to be compared to measurements taken (or to be taken) at that same location in a visual field test.

[0114] Alternatively, the locations of the points on the retina to be stimulated by the optical system 120 and from which the OCT data are acquired by the FD-OCT imaging system 130 can be selected by the controller 140 based on a retinal image of the eye 160. The ORG data 150 finally generated by the controller 140 is then determined from one or more regions of the retina under study. The ORG data 150 thus generated can be compared in a similar manner to measurements obtained (or to be obtained) in a visual field test by mapping retinal locations associated with the items of OCT / ORG data to conjugate locations in the visual field of the eye 160. The items of ORG data 150 and the visual field test measurements may not have been acquired at respective optically conjugate pairs of points in this case, but may still be meaningfully compared. This alternative is described in more detail below with reference to FIG. 12.

[0115] 11 is a flow diagram illustrating a process by which the controller 140 can determine, based on points in the visual field of the eye, an indication of a target location on the retina where a light stimulus is to be applied and an indication of a location on the retina where OCT data 135 is to be acquired, to facilitate a comparison of visual field test data with ORG data 150 generated by the controller 140. The controller 140 can perform this process prior to performing the process described with reference to FIG. 7, whereby the controller 140 controls the FD-OCT imaging system 130 to acquire OCT data for each of a plurality of second portions of the retina of the eye 160, the second portions corresponding to the respective first portions of the retina to which a light stimulus is applied. However, the controller 140 can alternatively perform the process of FIG. 11 in parallel with the process of FIG. 7.

[0116] In process S1101 of FIG. 11, the controller 140 determines an indication of a respective retinal location of each second portion of the retina from which OCT data 135 will be acquired by the FD-OCT imaging system. The controller 140 does this by determining, for each of a plurality of separate points in the field of view of the eye 160, an indication of a corresponding optically conjugate retinal location for that point. The plurality of points in the field of view of the eye 160 may be an arrangement (e.g., on a grid or array) of points of results of a visual field test (e.g., automated static perimetry, kinetic perimetry, or frequency-doubled perimetry) that can be compared with the ORG data 150 to be generated by the controller 140, as in this exemplary embodiment, so that the ORG data 150 can be acquired from substantially the same portion of the field that is illuminated by the stimuli used in the visual field test and whose response to the stimuli is evaluated in the visual field test. The plurality of points in the visual field may be provided by a visual field test device, such as an Octopus® visual field test device or a Humphrey® Field Analyzer (HFA).

[0117] In process S1102 of FIG. 11, the controller 140 determines each of the plurality of indices 141 (the indices 141 indicate target locations on the retina where the optical stimuli are to be applied by the optical system 120). The optical stimuli are then appropriately applied to stimulate the portions of the retina for which the ORG data 150 are intended to be acquired. This determination in process S1102 of FIG. 11 is based on corresponding indication information in the indication information determined in process S1101 of FIG. 11 (which indicates the location of each second portion of the retina). Here, at least a portion of each second portion of the retina is positioned relative to the first portion. The location of the first portion is represented by the indices 141 and can be stimulated by the optical stimuli applied thereto during the acquisition of at least a portion of the OCT data 135. The corresponding first and second portions can, for example, at least partially overlap. In this way, once at least some (i.e., one or more) target location indices indicating the target locations on the retina where the optical stimuli are to be applied are determined, the ORG data 150 generation process, described above with reference to FIG. 7, can begin.

[0118] The location of the second portion of the retina may include a representative location of the second portion 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). The location of the second portion may thus be expressed in Cartesian coordinates (x x y ) relative to a reference location (e.g., a point on the retina through which the optical axis or visual axis of the eye 160 passes, or the location of an anatomical landmark of the retina such as the fovea or optic disc). x ,y n ,z n ) or any other coordinate system. A corresponding position in the field of view of the eye 160 that is optically conjugate with the position of the second portion of the retina can be defined by a first angle α from the visual axis of the eye 160 in a temporo-nasal direction of the eye 160 and a second angle β from the visual axis of the eye 160 in a superior-inferior direction of the eye 160, or by any other suitable coordinate system.

[0119] FIG. 12 is a flow diagram illustrating a process by which the controller 140 selects a set of indices 141, each indicating a target location on the retina to which light stimuli are to be applied by the optical system 120 and a corresponding location from which OCT data 135 is to be acquired by the FD-OCT imaging system 130, and maps the locations on the retina from which the OCT data 135 is acquired to corresponding locations in the visual field of the eye 160, enabling the generated ORG data 150 to be compared to the results of a visual field test performed on the eye 160.

[0120] In process S1201 of FIG. 12, the controller 140 acquires a plurality of indices 141 based on a retinal image of the eyeball 160. The controller 140 acquires a plurality of indices 141 using a retinal position specified by a user (e.g., as described with reference to process S51 of FIG. 5) and sets the coordinates of each of the array of points on the retina to which the light stimulus is applied as the indices 141. The array of points is then superimposed on a retinal region requiring ORG data (e.g., the macular region). Alternatively, the controller 140 can automatically acquire the plurality of indices 141 based on, for example, a retinal image of the eyeball 160 and information indicative of a spatial distribution of photoreceptor cells across the retina of the eyeball 160. This distribution can be estimated or predicted based on previous research (measurements) on the spatial distribution within the human retina, such as the report by JB Jonas et al. in "Count and density of human retinal photoreceptors" (Graefe's Arch Clin Exp Ophthalmol230, pages505-510,1992).

[0121] 12, in process S1202, the controller 140 determines, based on the aforementioned information, an indication of a respective location on the retina for each second portion of the retina from which OCT data is acquired by the FD-OCT imaging system 130. The corresponding first and second portions are either at least partially overlapping (e.g., as in the optical configurations described with reference to FIGS. 3A-3B) or spaced apart but sufficiently close to each other (e.g., as can be achieved with the optical configurations described with reference to FIG. 3E) such that a light stimulus applied to the first portion can elicit a response from the retina in the second portion.

[0122] In process S1203 of Fig. 12, the controller 140 determines, for each second portion of the retina, a respective indication of a position in the field of view of the eye 160 of a point that is optically conjugate to the position of the second portion on the retina. This can be performed by the controller 140 using a mapping between points on the retina of the eye 160 and points that are optically conjugate in the field of view of the eye 160. This mapping can be determined using any technique known to the person skilled in the art, for example, it can be based on a ray tracing model of the eye 160 or it can be based on a ray tracing model of the eye defined, for example, by the average parameters of a set of eyes sampled from a population.

[0123] 13 is a schematic diagram of a tabular data structure 1300 that can be stored by controller 140 in a memory of controller 140, as in this exemplary embodiment. Data structure 1300 includes an indication of the location of the second portion on the retina (x n ,y n ,z n ) in the first column of the table (optional), and an indication of the position of the point in the field of the eye that is conjugate to the position of the second part (α n ,β n ) in the second column of the table, and the corresponding ORG data [XXX] n In the third column of the table, each column of the data structure 1300 thus contains an indication (x n ,y n ,z n ) is an indication (α n ,β n ) and each ORG data [XXX] n However, it will be appreciated that the data structure 1300 is not limited in this respect and may take other forms. The column headings are included for illustrative purposes only and may not be construed as limiting the scope of the invention. n It should be noted that the format of may take different forms as discussed above in connection with process S54 of FIG.

[0124] The stored ORG data and its associated location within the visual field of the eye 160 can be used to complement visual field testing of the eye 160 and provide further information that may be useful in determining the cause of blind spots or reduced retinal sensitivity within the visual field of the eye 160.

[0125] FIG. 14 is a flow diagram showing a process in which, as in this exemplary embodiment, the controller 140 obtains data indicating how measurements of the patient's ability to view light stimuli localized to different portions of the retina of the eye 160 at different locations on the retina are distributed over at least a portion of the visual field of the eye 160, and the controller controls the map display 142 to display, for comparison purposes, a first map indicating how the patient's ability to view light stimuli with the eye 160 is distributed over at least a portion of the visual field of the eye 160, and a second map indicating how the retinal response to the light stimuli indicated by each stored marking information is distributed over at least a portion of the visual field of the eye 160.

[0126] In process S1401 of Figure 14, the controller 140 obtains data indicative of how measurements of a subject's ability to see, at each location on the retina, a light stimulus localized to each different portion of the retina of the eye 160 are distributed across at least a portion of the visual field of the eye 160. Figure 15 is a flow diagram illustrating a process by which the controller 140 may obtain this data, as in this exemplary embodiment.

[0127] 15, in process S1501, the controller 140 receives respective indication information from the subject regarding whether the subject viewed each light stimulus applied to a plurality of first portions of the retina by the optical system 120. For example, the FD-OCT device 100 includes a button (which may be, for example, a physical button or a virtual button on a display of the FD-OCT device 100) that can be pressed by the subject when the subject views the light stimulus applied by the light stimulus.

[0128] 15, the controller 140 associates each received instruction with a respective instruction of a location of a respective first portion on the retina. The controller 140 can accomplish this, for example, by matching the instruction received from the subject to one of the periods during which the optical system 120 applied a light stimulus to one of the first portions of the retina.

[0129] In process S1503 of Figure 15, the controller 140 determines, for each respective indication of the location of each respective first portion of the retina, a respective indication of a corresponding location within the field of view of the eye 160 of a point that is optically conjugate with respect to the location of each respective first portion on the retina. The controller 140 can accomplish this, for example, using the techniques described with respect to process S1203 of Figure 12.

[0130] The controller 140 can alternatively obtain the aforementioned data (indicating how measurements of the subject's visual ability at different locations on the retina of the eye 160 in response to light stimuli localized to different parts of the retina are distributed over at least a portion of the visual field of the eye 160) by receiving visual field test data obtained from the eye 160 (e.g. by a dynamic or static perimetry device). For example, the visual field test data can be obtained from the eye 160 by performing a visual field test on the eye 160k using a visual field test device such as an Octopus® perimetry device or a Humphrey® Field Analyzer (HFA). The visual field test data can be obtained more generally through perimetry methods including, for example, the use of tangent screens, the use of Goldmann perimeters, automated perimetry, and microperimetry (described in more detail below). Furthermore, the perimetry format can use either a static or dynamic presentation of visual field test stimuli, such that, for example, a static or kinetic perimetry test can be performed. Furthermore, the visual field test stimuli used can be selected so that a visual field specific perimetry test can be performed, for example a photoreceptor specific perimetry test, such as a photopic perimetry test or a scotopic perimetry test.

[0131] The visual field test data obtained from the eye 160 includes a value indicative of the subject's ability to see the light stimulus in the visual field of the eye 160, presented at each of a number of different positions in the visual field of the eye 160. For example, when 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 value may be indicative of the patient's retinal sensitivity (in dB) in a numerical display output from the HFA, or a grayscale value in a grayscale plot output from the HFA. More generally, the value may be a binary value (e.g., "0" or "1") indicating whether the subject saw the light stimulus, or may be indicative of a light intensity threshold indicating that the subject was able to see the light stimulus for a certain percentage of the time (e.g., 50%). The positions of the visual field of the eye 160 may be defined in a coordinate system similar to that described in process S1101 of FIG. 11. However, it will be understood that the form of the visual field test data is not limited thereto, and any form of visual field test data obtained using a visual field test on the eye 160 may be used.

[0132] 14, in optional process S1402, the controller 140 controls the map display device 142 to display a first map (which may be similar to that indicated by at least some of the acquired visual field test data) showing how the subject's ability to see the light stimulus with the eye 160 is distributed across at least a portion of the visual field of the eye 160 based on at least some of the data acquired in process S1401 of FIG 14. For example, if the visual field test data is acquired from the eye 160 by performing a visual field test of the eye 160 using an HFA, the first map may be the same as a numerical display or grayscale plot output from the device.

[0133] 16 is a schematic diagram of an exemplary first map 1400 displayed in process S1402 of FIG. 14. In this example, the acquired data is visual field test data obtained from a visual field testing device. In this case, the visual field test data includes values ​​V1 to V 24, each of which indicates the threshold light intensity at which the subject was able to see the light stimulus in the visual field 50% of the time at that location, as previously described, plotted on a first axis 1410 corresponding to a first angle α and a second axis 1420 corresponding to a second angle β. However, the first map 1400 may take different forms depending on the type of visual field test used, such as a Goldmann visual field plot if the visual field test was performed using a Goldmann perimeter.

[0134] 14, in 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 a portion of the stored ORG data 150 and the stored indications of corresponding respective positions within the visual field of the eye 160. The second map indicates how the physiological responses of the retina to the light stimuli indicated by at least a portion of the stored ORG data 150 are distributed over at least a portion of the visual field of the eye 160.

[0135] 17 shows an example second map 1500 displayed in process S1403 of FIG 14. The second map 1500 is a representation of the stored ORG data I1-I2, which show the retinal response at corresponding locations of the second portion on the retina, as described above. 16 The ORG data I1 to I2 are displayed on a plot of the field of view of the eyeball similar to the first map 1400. 16 may, as in this exemplary embodiment, indicate a preliminary "alpha" magnitude of the retinal response (or alternatively, a "beta" magnitude of the retinal response) at a corresponding location on a second portion of the retina. This second map 1500 may be displayed adjacent to the first map 1400 on the map display 142, for example to facilitate comparison of the two maps. However, the second map 1500 may alternatively be overlaid on the first map 1400, and the acquired visual field test data V1-V 24 and the saved ORG data I1~I 16 are displayed in a single plot on a first axis 1410 corresponding to the first angle α and a second axis 1420 corresponding to the second angle β.

[0136] For comparison, the positions in the visual field of the eye 160 at which the stored ORG data 150 are displayed on the second map in process S1403 of FIG. 14 are the same positions at which the data acquired in process S1401 of FIG. 14 are displayed on the first map in process S1402 of FIG. 14. The data acquired at each position can therefore be easily and directly compared with the ORG response of the eye 160. This can help to improve the certainty of diagnosing the cause of any defects in the visual field of the eye 160. This can be achieved as described above with respect to the process of FIG. 11 and can be particularly advantageous if the first and second maps are superimposed, since the physician can see the respective ORG data 150 and the acquired data side by side at each position (e.g. by displaying the respective values ​​of the stored ORG data side by side at each position with the respective values ​​of the visual field test data).

[0137] In optional process S1404 of Figure 14, controller 140 compares the data of the first map to the data of the second map and identifies at least one region in at least a portion of the field of view based on the comparison. Controller 140 can identify at least one of one or more first regions, one or more second regions, one or more third regions, and one or more fourth regions of the field of view or portion of the field of view displayed in the map based on the comparison. Each of these regions can be identified by the controller 140, as in this exemplary embodiment, by determining whether the values ​​of the visual field test data at each position of the visual field of the eye 160 indicate that the subject can see a light stimulus (e.g., of a particular light intensity at least 50% of the time) at each individual position (within the visual field) and whether each of the ORG data at each corresponding position (e.g., the position closest to each of the positions compared to the same position or each of the other remaining positions) indicates a physiological response to the light stimulus that satisfies a predetermined condition. Satisfying a predetermined condition may mean that the physiological response to the light stimulus indicates a healthy eye physiological response to the light stimulus (i.e., a healthy retinal response). For example, if each of the ORG data includes a set of values ​​each indicating a certain magnitude of retinal response to the light stimulus, the predetermined condition may be that the value is equal to or greater than a threshold value. Thus, a value equal to or greater than the threshold value may indicate a healthy retinal response, while a value below the threshold value may indicate an unhealthy retinal response. The comparison performed by controller 140, as in this exemplary embodiment, determines the relationship between the data of the first map and the data of the second map for each of a plurality of regions into which the first map and the second map are divided in any suitable manner: They can be classified into one of the four categories above.

[0138] In this exemplary embodiment, one or more first regions (i.e., different first regions) of the displayed visual field indicate that the subject can see the light stimulus in the one or more first regions, and further indicate that one or more corresponding regions of the retina provided a physiological response to the light stimulus that meets a predetermined condition. These one or more first regions can thus be considered to correspond to regions of the retina that have healthy (normal) function.

[0139] One or more second regions (i.e., different second regions) of the displayed visual field indicate that the subject is unable to see the light stimulus in the one or more second regions, and further indicate that one or more corresponding regions of the retina have provided a physiological response to the light stimulus that meets the predetermined condition. These one or more second regions can therefore be considered to correspond to retinal regions where the subject is unable to see the applied stimulus, even though the retina responds normally to the light stimulus (although this does not exclude the possibility that the subject could have seen the stimulus if a higher intensity stimulus had been applied in the visual field test). This suggests to the physician that the subject's inability to see may not be due to a malfunction of the retinal photoreceptors, but to something else, such as the communication pathway between the subject's retinal photoreceptors and the brain. This can guide the physician to arrive at the correct diagnosis more quickly.

[0140] One or more third regions (i.e., different third regions) in the displayed visual field indicate that the subject was able to see the light stimulus in one or more third regions, and further indicate that one or more corresponding regions of the retina provided a physiological response to the light stimulus that did not meet the predetermined condition. These one or more third regions may thus be associated with the subject's erroneous indication that he or she was able to see the light stimulus. Such regions may be retested in a further visual field test or may be excluded (or may be given a lower confidence weight) from the analysis of retinal function to further improve the accuracy of the physician's diagnosis.

[0141] One or more fourth regions (i.e., different fourth regions) in the displayed visual field indicate an inability of the subject to see the light stimulus in the one or more fourth regions, and further indicate that one or more corresponding regions of the retina provided a physiological response to the light stimulus that does not meet the predetermined condition. These one or more fourth regions thus correspond to one or more regions of the retina that are not functioning properly, and identifying them may save a physician time by focusing on these regions first when analyzing the retinal function of the eye 160.

[0142] Optionally, in process S1405 of FIG. 14, the controller 140 controls the map display 142 to display any identified regions in at least one of the first map, the second map, and the third map that show at least a portion of the visual field of the eyeball 160. FIG. 18 shows an example of a third map 1600 that can be displayed by the map display 142 in process S1405 of FIG. 14. The third map 1600 is on a plot similar to that of the exemplary first map 1400 and the exemplary second map 1500 (i.e., plotted along a first axis 1410 corresponding to the first angle α and a second axis 1420 corresponding to the second angle β). The third map 1600 shows a region 1601 identified as the aforementioned first region, two regions 1602, 1603 identified as the aforementioned second region, a region 1604 identified as the aforementioned third region, and three regions 1605, 1606, 1607 identified as the aforementioned fourth region. These regions 1601-1607 may alternatively be shown superimposed on the first map, the second map described above, or on an overlay of the first and second maps.

[0143] While the display of a first map showing the subject's ability to see light stimuli distributed over at least a portion of the visual field of the eye 160 and the display of a second map showing the physiological response of the retina to the light stimuli as indicated by the respective stored instruction information as distributed over at least a portion of the visual field of the eye 160 have been described above, in an alternative implementation of the exemplary embodiment, the controller 140 can control the map display 142 to display a fourth map showing the subject's ability to see light stimuli in the eye 160 distributed over at least a portion of the retina of the eye 160 and a fifth map showing the physiological response of the retina to the light stimuli as indicated by at least a portion of the stored ORG data as distributed over at least a portion of the retina of the eye 160. This is preferable for the physician, since when overlaid on the retinal image of the eye 160, the visual field test data and the ORG data can be compared and the two sets of data can be used to interpret, for example, structural features of the eye 160 in the image. Specifically, the fourth map is obtained from a microperimetry test of the eye 160, and as described below, the respective ORG data can be mapped and displayed together with the microperimetry results obtained by the controller 140.

[0144] FIG. 19 is a flow diagram showing a process in which, as an alternative implementation of an exemplary embodiment, the controller 140 obtains data indicative of how measurements of the subject's visual ability at different locations on the retina in response to light stimuli localized to different portions of the retina of the eye 160 are distributed over at least a portion of the retina of the eye 160 and controls the map display device 142 to display a fourth map and a fifth map.

[0145] In process S2101 of FIG. 19, the controller 140 stores, for each of a plurality of second portions of the retina, respective ORG data 150 generated from OCT data 135 acquired from the second portion in association with respective indication information of the position of the second portion on the retina.

[0146] In process S2102 of Figure 19, controller 140 obtains data indicative of how measurements of the subject's visual ability at different locations on the retina in response to light stimuli localized to different portions of the retina of eye 160 are distributed across at least a portion of the retina. Figure 20A is a flow diagram illustrating the process by which controller 140 obtains this data, as in this exemplary embodiment.

[0147] 20A, in process S1901, the controller 140 receives visual field test data acquired from the eye 160 by a visual field testing device. The visual field test data includes a measurement of the subject's visual ability to light stimuli applied from multiple points in the visual field of the subject's eye 160. The controller 140 may acquire the visual field test data, for example, from an HFA or other perimeter as previously described.

[0148] In process S1902 of Figure 20A, the controller 140 determines, for each of the plurality of points in the field of view of the eye 160, a respective indication of a corresponding point on the retina that is optically conjugate to the point. The controller 140 may achieve this 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 (which is obtained in the manner described above) to generate the distribution information.

[0149] As an alternative to process S1901 and process S1902, the controller 140 may receive visual field test data obtained from the eye 160 by a visual field test device. The visual field test data indicates how measurements of the subject's visual ability in response to light stimuli applied to different locations on the retina of the eye 160 are distributed over at least a portion of the retina of the eye 160. For example, the visual field test data can be obtained from a micro-perimeter device (e.g., a Nidek® MP-3 microperimeter, a Zeiss Humphrey® Field Analyzer Model 860, or a Haag-Streit Octopus 900Pro®), the output of which also includes, as distribution information, an indication of the locations on the retina of the eye 160 to which the light stimuli from the micro-perimeter device are delivered (e.g., in the form of coordinates of points on a retinal image obtained by micro-perimetry).

[0150] FIG. 20B illustrates a flow diagram of a process by which the controller 140 alternatively obtains the aforementioned data.

[0151] 20B, the controller 140 receives indication information provided by the subject regarding whether the subject viewed each light stimulus applied to each of the multiple first portions of the retina by the optical system 120. For example, the FD-OCT device 100 may include a button (which may be, for example, a physical button or a virtual button on a display of the FD-OCT device 100) that the subject can press when the subject views the light stimulus applied by the optical system 120.

[0152] In process S1904 of Figure 20B, the controller 140 associates each of the received instruction information with a respective instruction information of a position of a respective first portion on the retina. The controller 140 can achieve this, for example, by matching the instruction information received from the subject to one of the periods during which the optical system 120 applied a light stimulus to one of the first portions of the retina.

[0153] 19, in optional process S2103, the controller 140 controls the map display device 142 to display a fourth map showing how the subject's ability to see (by the eye 160) the light stimulus is distributed over at least a portion of the retina of the eye 160 based on at least some of the data acquired in process S2101. The fourth map may include an image of a portion of the retina of the eye 160, for example, as acquired by a micro-perimetry device (e.g., a scanning laser ophthalmoscope included in the micro-perimetry device) or by the FD-OCT device 100 (e.g., a scanning laser ophthalmoscope forming part of the FD-OCT imaging system 130 or -OCT device 100).

[0154] 21 illustrates an exemplary fourth map 1700, which is a representation of the values ​​V1 through V2 from the exemplary first map 1400 of FIG. 24 However, these are distributed on an image of a region 800 of the retina of the eyeball 160. 24 The location is based on distribution information.

[0155] In optional process S2104 of Fig. 19, the controller 140 controls the map display 142 based on at least a portion of the generated ORG data and the location of the second portion of the retina generated by at least a portion of the ORG data to display a fifth map for comparison with the fourth map. The fifth map indicates how the physiological response of the retina to the light stimulus represented by at least a portion 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, similar to that described above for the fourth map.

[0156] 22 illustrates an exemplary fifth map 1800, which is a representation of the stored ORG data values ​​I1-I2 from the exemplary second map 1500 of FIG. 16 However, these are distributed on the image of the area 800 of the retina of the eyeball 160 in FIG. 22. The stored ORG data I1 to I 16The locations of the indices in process S71 of Fig. 7 or the second part of process S73 of Fig. 7 can then be determined as described above, using the distribution information in process S2102 to set the same locations as the visual field test data values ​​on the retina of the eye 160. Using the same locations for each ORG data 150 and the visual field test data values ​​facilitates a side-by-side comparison of the data sets by the physician and allows for a direct association between the data sets at each location.

[0157] The fourth and fifth maps can be superimposed in a manner similar to that described above with respect to the first and second maps. Furthermore, by comparing the fourth and fifth maps in a manner similar to that described above with respect to the first and second maps, the controller 140 can identify one or more first regions, one or more second regions, one or more third regions, and one or more fourth regions distributed over at least a portion of the retina of the eye 160. Furthermore, these identified regions can be displayed by the map display device in at least one of a fourth map, a fifth map, and a sixth map indicative of at least a portion of the retina of the eye 160 in a manner similar to that described above with respect to the first map, the second map, and the third map. The controller 140 can execute the above process to control the map display device 142 to display at least one of the fourth map, the fifth map, and the sixth map in addition to at least one of the first map, the second map, and the third map.

[0158] The above-described exemplary embodiment of the FD-OCT device 100 includes a steerable optical system 120 that can be controlled by the controller 140 to vary the location on the retina where the light stimulus is applied while the fixed gaze direction of the eye is maintained by the fixation target 110 (by keeping the position of the fixation target 110 fixed relative to the eye 160), and applies a localized stimulus that is localized to a portion of the retina, but the form of the optical system that provides the fixation target and the light stimulus is not limited thereto. For example, in some exemplary embodiments, especially when the amount of ORG data acquired in each imaging session is relatively small, the fixation target may be omitted entirely and the subject may be required to maintain a central gaze direction during the session. In other exemplary embodiments, the optical system that provides the localized light stimulus may not be steerable. The location on the retina where the light stimulus is applied may instead be adjusted by changing the position of the fixation target relative to the eye 160, allowing the eye to be steered. In other exemplary embodiments, instead of a localized light stimulus, a conventional optical system that illuminates the retina over a large area (wide area) may be used. However, when such conventional optical systems are used, obtaining OCT data from multiple portions of the retina generally requires the use of a light adaptation period between OCT acquisitions at each portion (usually by having all portions to be imaged illuminated by the optical system), which can slow down the rate at which the FD-OCT device generates ORG data 150 and can potentially degrade the quality of the ORG data due to subject movement resulting from longer imaging procedures and the associated potential for increased discomfort facing the FD-OCT device 100.

[0159] In alternative embodiments of the above type, the controller 140 is generally configured to (i) control the FD-OCT imaging system 130 to acquire OCT data 135 for multiple portions of the retina such that, for each portion of the multiple portions of the retina, at least a portion of the OCT data acquired from that portion is acquired after a respective light stimulus is applied to that portion by the optical system 120, (ii) generate, for each portion of the multiple portions of the retina, respective ORG data 150 indicative of the respective response of the portion of the retina to the light stimulus applied to the portion of the retina based on the acquired OCT data 135, and (iii) store, for each portion of the multiple portions of the retina, the respective ORG data 150 generated for that portion in association with respective indications of a position within the field of view of the eye 160 that is optically conjugate to a position corresponding to that portion of the retina.

[0160] Moreover, in such an alternative exemplary embodiment, the controller 140 can then control the FD-OCT device as described with reference to Fig. 23 to perform a method of acquiring ORG data 150 indicative of a physiological response of a retina of an eye 160 to a light stimulus. The FD-OCT device controlled in this manner comprises an optical system 120 operable to apply a light stimulus in one of the possible forms described above, e.g., to the retina. The FD-OCT device further comprises the above-mentioned FD-OCT imaging system 130, which is operable to acquire OCT data 135 by imaging a portion of the retina.

[0161] In process S3101 of FIG. 23, the controller 140 controls the FD-OCT imaging system 130 to acquire OCT data 135 for multiple portions of the retina, such that for each portion of the multiple portions of the retina, at least a portion of the OCT data obtained from that portion is acquired after a respective light stimulus is applied to that portion by the optical system 120.

[0162] In process S3102 of FIG. 23, based on the acquired OCT data 135, the controller 140 generates, for each of the multiple portions of the retina, respective ORG data 150 indicating the respective response of that retinal portion to the light stimulus applied to the portion of the retina by the optical system 120.

[0163] In process S3103 of FIG. 23, for each of a plurality of portions of the retina, the controller 140 stores the respective ORG data 150 generated for that portion in association with respective indications of a position within the field of view of the eyeball 160 that is a point optically conjugate to a position corresponding to that portion of the retina.

[0164] Alternatively, the controller 140 may execute a method for controlling the FD-OCT device to obtain ORG data 150 indicative of a physiological response of the retina of the eye 160 to a light stimulus, as will now be described with reference to Fig. 24. The FD-OCT device controlled according to this method comprises an optical system operable to apply a localized or non-localized (wide field) light stimulus to the retina in one of the aforementioned ways. The FD-OCT device further comprises the above-mentioned FD-OCT imaging system 130, which is operable to obtain OCT data 135 by imaging a portion of the retina.

[0165] In process S4101 of FIG. 24, the controller 140 controls the FD-OCT imaging system 130 to acquire OCT data 135 for multiple portions of the retina, such that for each portion of the multiple portions of the retina, at least a portion of the OCT data obtained from that portion is acquired after a respective light stimulus is applied to that portion by the optical system 120.

[0166] In process S4102 of FIG. 24, based on the acquired OCT data 135, the controller 140 generates, for each of the multiple portions of the retina, respective ORG data 150 indicating the respective response of the portion of the retina to a light stimulus applied to the portion of the retina.

[0167] In process S4103 of FIG. 24, the controller 140 stores, for each of the multiple portions of the retina, respective ORG data 150 generated from the OCT data 135 acquired from that portion in association with respective indications of the position of that portion on the retina.

[0168] In process S4104 of Fig. 24, the controller 140 obtains data indicative of how measurements of the subject's ability to see light stimuli applied to different locations on the retina of the eye 160 are distributed across at least a portion of the retina of the eye 160. The controller 140 can be configured to obtain data indicative of how measurements of the subject's ability to see light stimuli applied to different locations on the retina of the eye 160 are distributed across at least a portion of the retina by receiving visual field test data obtained from the eye 160 by a visual field test device, the visual field test data including measurements of the subject's ability to see light stimuli applied from a plurality of points in the visual field of the subject's eye 160, and determining, for each point of the plurality of points in the visual field, a respective indication of a corresponding point on the retina that is optically conjugate to the point. Alternatively, the controller 140 can be configured to: The system can be configured to obtain data indicative of how measurements of the subject's ability to see light stimuli applied to different locations on the retina of the eye are distributed across at least a portion of the retina by receiving indications provided by the subject as to whether the subject saw each light stimulus applied by optical system 120 to each of a plurality of portions of the retina, and by associating each of the received indications with respective indications of the location of each portion on the retina.

[0169] The controller 140 can then control the display device 142 based on at least a portion of the data acquired in process S4104 of FIG. 24 to display, for example, the first map 1700 described above, which indicates the distribution of the subject's visual ability to a light stimulus in at least a portion of the retina of the eyeball 160, together with the second map 1800 described above for comparison with the first map 1700. Here, the second map 1800 indicates the distribution of the retinal response to a light stimulus in at least a portion of the retina of the eyeball 160, which is indicated by at least a portion of the generated ORG data 150. The controller 140 then compares the data of the first map 1700 with the data of the second map 1800, and identifies, based on the comparison, at least one of the regions 1601 to 1607 described above with reference to FIG. 18.

[0170] The methods described above with reference to Figures 23 and 24 can be performed by any type of controller 140 described herein, typically a computer executing computer-readable instructions of a computer program stored on a non-transitory storage medium (such as a CD, DVD or hard disk) or transmitted by a signal (such as in an internet download).

[0171] In the preceding description, exemplary aspects have been described with reference to several exemplary embodiments. This specification should therefore be considered illustrative rather than restrictive. Similarly, the shapes shown in the drawings, which highlight features and advantages of the exemplary embodiments, are presented for illustrative purposes only. The architecture of the exemplary embodiments is sufficiently flexible and configurable to be utilized in ways other than those shown in the accompanying figures.

[0172] Some aspects of the examples presented herein, such as the functionality of the controller 140, can be provided as computer programs or software, such as one or more programs having instructions or sequences of instructions. These, in one embodiment, are contained or stored in an article of manufacture, such as a machine-accessible or machine-readable medium, instruction storage, or computer-readable storage device, each of which may be non-transitory. The programs or instructions on the non-transitory machine-accessible or machine-readable medium, instruction storage, or computer-readable storage device can be used to program a computer system or other electronic device. Machine-readable or computer-readable media, instruction storage, and storage devices may include, but are not limited to, floppy diskettes, optical disks, and magneto-optical disks, or other types of media / machine-readable media / instruction storage / storage devices suitable for storing or transmitting electronic instructions. The techniques described herein are not limited to any particular software configuration. They may find applicability in any computing or processing environment. As used herein, the terms "computer-readable," "machine-accessible medium," "machine-readable medium," "instruction store," and "computer-readable storage device" are intended to include any medium capable of storing, encoding, or transmitting instructions or sequences of instructions for execution by a machine, computer, or computer processor, and causing the machine / computer / computer processor to perform any of the methods described herein. Furthermore, in the art, software is generally used to refer to something that, in one form or another (e.g., program, procedure, process, application, module, unit, logic, etc.), that takes an action and produces a result. Such expressions are merely a shorthand way of indicating that execution of the software by a processing system causes the processor to perform an action and produce a result.

[0173] Some or all of the functionality of controller 140 may also be implemented by the preparation of application specific integrated circuits, field programmable gate arrays, or by interconnecting an appropriate network of conventional component circuits.

[0174] The computer program product can be provided in the form of a storage medium, instruction store, or storage device having instructions stored thereon that can be used to control or cause a computer or computer processor to execute any of the procedures of the exemplary embodiments described herein. The storage medium / instruction store / storage device can include, by way of example and not limitation, optical disks, ROM, RAM, EPROM, EEPROM, DRAM, VRAM, flash memory, flash cards, magnetic cards, optical cards, nanosystems, molecular memory integrated circuits, RAID, remote data storage / archive / warehousing, and / or any other type of device suitable for storing instructions and / or data.

[0175] Some implementations stored on either a computer readable medium, instruction storage or storage device include software that controls the system hardware and enables the system or microprocessor to interact with a human user or other mechanisms that utilize the results of the exemplary embodiments described herein. Such software may include, but is not limited to, device drivers, operating systems, and user applications. Ultimately, such computer readable medium or storage device further includes software for performing the exemplary aspects of the present invention as described above.

[0176] The programming and / or software of the system includes software modules for performing the procedures described herein. In some exemplary embodiments herein, the modules include software, although in other exemplary embodiments herein, the modules include hardware or a combination of hardware and software.

[0177] While various exemplary embodiments of the present invention have been described above, it should be understood that they are presented for purposes of illustration and not limitation. It will be apparent to those skilled in the art that various changes in form and detail may be made. Thus, the present invention should not be limited by any of the exemplary embodiments described above, but should be defined only by the claims set forth below and their equivalents. It should also be understood that any steps recited in the claims do not necessarily have to be performed in the order presented.

[0178] Although this specification contains many details of specific embodiments, they should not be considered as limiting the scope of any invention or what is claimed, but rather should be understood as a description of features specific to the specific embodiments described herein. Certain features described in the context of separate embodiments herein can also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, even if features are described above as acting in a particular combination and are initially claimed as such, one or more features from the claimed combination can be deleted from the combination in some cases, and the claimed combination can be directed to a subcombination or a variation of the subcombination.

[0179] It may also be advantageous to multitask and parallelize processing in certain circumstances.Furthermore, it should be understood that the separation of various components in the above embodiments should not be understood to require such separation in all embodiments, and that the above program elements and systems may generally be integrated into a single software product or packaged into multiple software products.

[0180] Having now described several exemplary embodiments and implementations, it should be apparent that the foregoing has been presented by way of illustration and not limitation. In particular, while many of the examples presented herein include specific combinations of device or software elements, these elements may be combined in different ways to achieve the same purpose. Acts, elements, and features discussed only in connection with one embodiment are not intended to be excluded from a similar role in other embodiments.

Claims

1. 1. A Fourier Domain Optical Coherence Tomography, FD-OCT, apparatus (100) for acquiring opto-retinography, ORG, data (150) indicative of a physiological response of a retina of a subject's eye 160 to a light stimulus, comprising: an optical system (120) operable to apply the light stimulus to the retina; an FD-OCT imaging system (130) operable to acquire OCT data (135) by imaging a portion of the retina; A controller (140), controlling the FD-OCT imaging system (130) to acquire, for each of a plurality of portions of the retina, at least a portion of the OCT data acquired from the portion after a respective light stimulus is applied to the portion by the optical system (120), thereby acquiring OCT data (135) for the plurality of portions of the retina; generating, for each of the plurality of portions of the retina based on the acquired OCT data (135), respective ORG data (150) indicative of the respective response of the portion of the retina to the light stimulus applied to the portion of the retina; storing, for each of the plurality of portions of the retina, the respective ORG data (150) generated for said portion in association with a respective indication of a location within the field of view of the eye (160) that is a point optically conjugate with a corresponding location of said portion of the retina; A controller configured to: A Fourier domain optical coherence tomography (FD-OCT) apparatus (100) comprising:

2. The FD-OCT device (100) of claim 1, further configured to determine (S1101) respective indications of positions on the retina for each of the plurality of portions of the retina from which OCT data (135) is acquired by the FD-OCT imaging system (130) by determining, for each of a plurality of points in the field of view of the eye (160), respective indications of corresponding positions on the retina that are optically conjugate to the point.

3. The controller (140) determines (S1202) based on an image of the retina of the eye (160) respective indications of retinal locations of each of the portions of the retina from which OCT data (135) are acquired by the FD-OCT imaging system (130); determining (S1203), for each of the plurality of portions of the retina, a respective indication of the location within the field of view of the eye (160) of a point optically conjugate with the location of the portion on the retina; The FD-OCT apparatus according to claim 1 , further configured as follows.

4. Further comprising a display device (142); The controller (140) obtaining data indicative of how measurements of a subject's ability to see light stimuli localized to different portions of the retina of the eye (160) at different locations of the retina are distributed across at least a portion of the visual field of the eye (160) (S1401); Controlling the display device (142) to display a first map (1400) showing how the subject's ability to see the light stimulus is distributed over at least a portion of the visual field of the eye (160) based at least in part on the acquired data (S1402); Controlling the display device (142) to display (S1403) a second map (1500) in comparison to the first map (1400) based at least in part on the stored ORG data (150) and the associated stored instructional information, the second map (1500) being a map showing how the physiological response of the retina to the light stimulus as indicated by at least a portion of the stored ORG data (150) is distributed over at least a portion of the visual field of the eye (160); The FD-OCT device according to claim 1 , further configured as follows.

5. 1. A Fourier Domain Optical Coherence Tomography, FD-OCT, apparatus (100) for acquiring opto-retinography ORG data (150) indicative of a physiological response of a retina of an eye (160) of a subject to a light stimulus, comprising: an optical system (120) operable to apply the light stimulus to the retina; an FD-OCT imaging system (130) operable to acquire OCT data (135) by imaging a portion of the retina; A controller (140), controlling the FD-OCT imaging system (130) to acquire, for each of a plurality of portions of the retina, at least a portion of the OCT data acquired from the portion after a respective light stimulus is applied to the portion by the optical system (120), thereby acquiring OCT data (135) for the plurality of portions of the retina; generating, for each of the plurality of portions of the retina based on the acquired OCT data (135), respective ORG data (150) indicative of the respective response of the portion of the retina to the light stimulus applied to the portion of the retina; storing, for each of the plurality of portions of the retina, a respective set of ORG data (150) generated from OCT data (135) acquired from the portion in association with a respective indication of a location of the portion on the retina; obtaining data indicative of how measurements of a subject's ability to perceive light stimuli localized to different portions of the retina of the eye (160) at different locations of the retina are distributed across at least a portion of the visual field of the eye (160); A controller configured as follows: A Fourier domain optical coherence tomography, FD-OCT, apparatus (100), comprising:

6. The controller (140) may further comprise: data indicative of how measurements of the subject's ability to see light stimuli applied to different locations of the retina of the eye (160) are distributed across at least a portion of the visual field of the eye (160); receiving (S1901) visual field test data acquired from the eye (160) by a visual field testing device, the visual field test data including a measure of the subject's ability to view light stimuli applied from a plurality of points within the visual field of the subject's eye (160); determining (S1902), for each point of the plurality of points in the field of view of the eye (160), a respective indication of a corresponding point on the retina that is optically conjugate to the point; The FD-OCT device (100) of claim 5, configured to acquire by:

7. The controller (140) may further comprise: data indicative of how measurements of the subject's ability to see light stimuli applied to different locations of the retina of the eye (160) are distributed across at least a portion of the visual field of the eye (160); receiving (S1903) an indication provided by the subject as to whether the subject viewed each of the light stimuli applied to each of the portions of the retina by the optical system (120); and Associating each of the received instructions with a respective indication of a location of the respective portion on the retina (S1904); The FD-OCT device (100) of claim 5, configured to acquire by:

8. Further comprising a display device (142); A controller (140): Controlling the display device (142) to display a first map (1700) showing how the subject's ability to see the light stimulus is distributed over at least a portion of the retina of the eye (160) based at least in part on the acquired data (S2103); controlling the display device (142) to display a second map (1800) showing how responses of the retina to light stimuli represented by at least a portion of the generated ORG data (150) are distributed over at least the portion of the eye (160) for comparison with the first map (1700) based on at least a portion of the generated ORG data (150) and the location of the portion of the retina from which at least a portion of the ORG data was generated (S2104); The FD-OCT device (100) of claim 5, further configured as follows:

9. The controller (140) compares the data of the first map (1400, 1700) with the data of the second map (1500, 1800) and, based on the comparison, One or more first regions (1601) of at least a portion of the visual field, indicating that the subject can see a visual field testing light stimulus within 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 provided a physiological response to the light stimulus that meets 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 a visual field testing light stimulus within 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 provided a physiological response to the light stimulus that satisfies the predetermined condition; one or more third regions (1604) of the at least a portion of the visual field, indicating that the subject is able to see a visual field testing light stimulus within the one or more third regions (1604) of the at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provided a physiological response to the light stimulus that does not satisfy the predetermined condition; one or more fourth regions (1605, 1606, 1607) of the at least a portion of the visual field, indicating that the subject is unable to see a visual field testing light stimulus within the one or more fourth regions (1605, 1606, 1607) of the at least a portion of the visual field, and indicating that one or more corresponding regions of the retina provided a physiological response to the light stimulus that did not meet the predetermined condition; The FD-OCT device (100) of claim 4 or claim 8, further configured to identify at least one of:

10. The FD-OCT device (100) further includes a fixation target (110) for fixing the gaze direction of the eyeball (160), the optical system (120) is operable to apply the light stimulus to the retina such that illumination of the retina by the light stimulus is localized to a portion of the retina, the optical system (120) is controllable by the controller (140) to vary the position on the retina to which the light stimulus is applied, and comprises a light source (301) configured to generate light that provides the light stimulus, and one or more scanning elements (312, 314) configured to direct the light to the retina; The controller (140) obtaining an indication (141) of a target location on the retina to which the light stimulus is applied by the optical system (120); configured to control the one or more scanning elements (312, 314) of the optical system (120) using the acquired indicia (141) to direct the light to a first portion of the retina at the target location while a position of the fixation target (110) relative to the eye (160) is fixed; controlling the FD-OCT imaging system (130) to acquire OCT data (135) of a second portion of the retina, where at least a portion of the second portion of the retina is positioned relative to the first portion such that the second portion can be stimulated by the applied light stimulus during acquisition of at least a portion of the OCT data (135); generating ORG data (150) based on the acquired OCT data (135) of the second portion of the retina; The FD-OCT apparatus according to claim 1 or 5, further configured as follows.

11. The FD-OCT imaging system (130, 320) comprises: an interferometer (322) having a sample arm (324) and a reference arm (325); The sample OCT light (L) propagating along the sample arm (324) after being scattered from the retina ｏ ) and a reference OCT light (L) propagating along the reference arm (325). ｒ ) and a detector (323) configured to detect interference between Including, At least one of the one or more scanning elements (312, 314) is configured to capture the sample OCT light (L ｏ 11. The FD-OCT device (100) of claim 10, further configured to direct a first optical fiber (102) to the second portion of the retina and direct the sample OCT light scattered from the second portion of the retina to the detector (323).

12. The FD-OCT imaging system (130, 361) an interferometer (322) having a sample arm (324) and a reference arm (325); one or more scanning elements (363, 364); The sample OCT light (L) propagating along the sample arm (324) after being scattered from the retina ｏ ) and a reference OCT light (L) propagating along the reference arm (325). ｒ ) and a detector (323) configured to detect interference between Including, The one or more scanning elements (363, 364) are configured to capture the sample OCT light (L ｏ ) to the second portion of the retina, and the sample OCT light (L ｏ ) to the detector (323); and The FD-OCT device of claim 10, wherein the one or more scanning elements (363, 364) of the optical system (120, 360) are different from the one or more scanning elements (363, 364) of the FD-OCT imaging system (130, 361).

13. 1. A computer-implemented method for controlling a Fourier Domain Optical Coherence Tomography, FD-OCT, apparatus (100) to acquire opto-retinography, ORG, data (150) indicative of a physiological response of a retina of an eye (160) of a subject to a light stimulus, the method comprising: The FD-OCT device (100) an optical system (120) operable to apply the light stimulus to the retina; an FD-OCT imaging system (130) operable to acquire OCT data (135) by imaging a portion of the retina; Including, The computer-implemented method comprises: controlling the FD-OCT imaging system (130) to acquire, for each of a plurality of portions of the retina, at least a portion of the OCT data acquired from the portion after a respective light stimulus is applied to the portion by the optical system (120), thereby acquiring OCT data (135) for the plurality of portions of the retina; generating, for each of the plurality of portions of the retina based on the acquired OCT data (135), respective ORG data (150) indicative of the respective response of the portion of the retina to the light stimulus applied to the portion of the retina; storing, for each of the plurality of portions of the retina, the respective ORG data (150) generated for said portion in association with a respective indication of a location within the field of view of the eye (160) that is a point optically conjugate with a corresponding location of said portion of the retina; A computer-implemented method comprising:

14. 1. A computer-implemented method for controlling a Fourier Domain Optical Coherence Tomography, FD-OCT, apparatus (100) to acquire opto-retinography, ORG, data (150) indicative of a physiological response of a retina of an eye (160) of a subject to a light stimulus, the method comprising: The FD-OCT device (100) an optical system (120) operable to apply the light stimulus to the retina; an FD-OCT imaging system (130) operable to acquire OCT data (135) by imaging a portion of the retina; Including, The computer-implemented method comprises: controlling the FD-OCT imaging system (130) to acquire, for each of a plurality of portions of the retina, at least a portion of the OCT data acquired from the portion after a respective light stimulus is applied to the portion by the optical system (120), thereby acquiring OCT data (135) for the plurality of portions of the retina; generating, for each of the plurality of portions of the retina based on the acquired OCT data (135), respective ORG data (150) indicative of the respective response of the portion of the retina to the light stimulus applied to the portion of the retina; storing, for each of the plurality of portions of the retina, a respective set of ORG data (150) generated from OCT data (135) acquired from the portion in association with a respective indication of a location of the portion on the retina; obtaining data indicative of how measurements of a subject's ability to perceive light stimuli localized to different portions of the retina of the eye (160) at different locations of the retina are distributed across at least a portion of the visual field of the eye (160); A computer-implemented method comprising:

15. A computer program comprising computer readable instructions which, when executed by a computer, causes the computer to carry out the method of claim 13 or 14.

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