JP2023040529A - Ophthalmologic information processing apparatus, ophthalmologic apparatus, ophthalmologic information processing method and program - Google Patents

Abstract

To provide a novel technology for positioning a spectral image simpler and more accurately.SOLUTION: An ophthalmologic information processing apparatus includes an acquisition part and a positioning part. The acquisition part acquires a plurality of images of an eye to be examined which is acquired by sequentially receiving return light having wavelength ranges different from one another and returning from the eye to be examined which is irradiated with illumination light. The positioning part positions a plurality of images on the basis of OCT data acquired by executing optical coherence tomography with respect to an eye to be examined.SELECTED DRAWING: Figure 3

Description

The present invention relates to an ophthalmic information processing apparatus, an ophthalmic apparatus, an ophthalmic information processing method, and a program.

Fundus observation is useful for diagnosing fundus diseases and estimating the sclerotic state of the whole body (especially cerebral blood vessels) by observing the retina, blood vessels, optic nerves, etc. through the pupil. For fundus observation, for example, a fundus image acquired by an ophthalmologic apparatus (fundus photographing apparatus) such as a fundus camera or a scanning light ophthalmoscope (SLO) is used.

In fundus observation, it is known that by acquiring multiple spectral fundus images over a wide analysis wavelength range, it is possible to extract various features of the fundus that are difficult to grasp with general fundus images. . For example, Patent Literature 1 and Patent Literature 2 disclose an ophthalmologic apparatus that acquires a spectral fundus image. For example, Non-Patent Document 1 and Non-Patent Document 2 disclose a method of applying a hyperspectral image as a spectral fundus image to the retina.

Acquisition of such a plurality of spectral fundus images requires a predetermined time. Positional deviation of the same part may occur between images. For example, Patent Literature 3 discloses a method of correcting the position and shape of any one of two images so that a plurality of feature points in each of the two images match.

JP-A-2006-158546 JP 2010-200916 A JP 2006-158547 A

Sophie Lemmments, et al. , "Hyperspectral Imaging and the Retina: Worth the Wave?", translational vision science & technology, August 5, 2020, Vol. 9, No. 9, Article 9 Edith R. Reshef, et al. , "Hyperspectral Imaging of the Retina: A Review", INTERNATIONAL OPHTHALMOLOGY CLINICS, August 21, 2020, Vol. 60, No. 1, pp. 85-96

As the resolution of spectral images such as spectral fundus images and spectral anterior segment images progresses, a new technique for more easily and highly accurately aligning spectral images is desired.

The present invention has been made in view of such circumstances, and one of its objects is to provide a new technique for more easily and highly accurately aligning spectral images. be.

A first aspect according to an embodiment includes an acquisition unit configured to acquire a plurality of images of the eye to be inspected obtained by sequentially receiving return light beams having different wavelength ranges from the eye to be inspected illuminated by the illumination light; an ophthalmologic information processing apparatus, comprising: an alignment unit that aligns the plurality of images based on OCT data obtained by performing optical coherence tomography on an eye to be inspected.

In the second aspect of the embodiment, in the first aspect, the OCT data is a detection result of interference light obtained by performing optical coherence tomography on the eye to be examined, a B-scan image, an OCTA (OCT Angiography ) image or en-face image.

In a third aspect of the embodiment, in the first aspect, the alignment unit aligns the image of the subject's eye with an OCT front image at a depth position corresponding to the wavelength range of the image.

A fourth aspect of the embodiment is, in any one of the first to third aspects, analyzing the first image and the second image among the plurality of images to determine the difference between the first image and the second image. and a positional deviation information generation unit that acquires positional deviation information between.

A fifth aspect of the embodiment is the fourth aspect, including a first determination unit that determines whether or not the positional deviation between the first image and the second image is large based on the positional deviation information, Based on the determination result obtained by the first determination section, the acquisition section re-acquires the first image or the second image.

A sixth aspect of the embodiment, in any one of the first to fifth aspects, includes a quality evaluation unit that calculates an evaluation value of quality of at least one of the plurality of images.

A seventh aspect of the embodiment is, in the sixth aspect, further comprising a second determination unit that determines whether the quality of the plurality of images is good or bad based on the evaluation value, and based on the determination result obtained by the second determination unit Then, the acquisition unit reacquires at least one of the plurality of images or all of the plurality of images.

An eighth aspect of the embodiment includes an illumination optical system that illuminates the eye to be inspected with illumination light, a light receiving optical system that sequentially receives return lights of the illumination light from the eye to be inspected that have different wavelength ranges from each other, and An OCT optical system that performs optical coherence tomography for eye examination, and the ophthalmologic information processing apparatus according to any one of the first to sixth aspects, wherein the acquisition unit is obtained by the light receiving optical system. The ophthalmologic apparatus sequentially acquires the plurality of images based on the received light reception result.

A ninth aspect of the embodiment is an acquisition step of acquiring a plurality of images of the eye to be inspected obtained by sequentially receiving return lights having different wavelength ranges from the eye to be inspected illuminated by the illumination light; and a registration step of registering the plurality of images based on OCT data obtained by performing optical coherence tomography on the eye examination.

In a tenth aspect of the embodiment, in the ninth aspect, the OCT data is a detection result of interference light obtained by performing optical coherence tomography on the eye to be examined, a B-scan image, an OCTA (OCT Angiography ) image, or an en-face image.

In the eleventh aspect according to the ninth aspect, the alignment step aligns the image of the subject's eye with an OCT front image at a depth position corresponding to the wavelength range of the image.

A twelfth aspect of the embodiment is, in any one of the ninth aspect to the eleventh aspect, analyzing the first image and the second image among the plurality of images to determine the difference between the first image and the second image. and a positional deviation information generation step of acquiring positional deviation information between.

A thirteenth aspect of the embodiment is the twelfth aspect, comprising a first determination step of determining whether or not the positional deviation between the first image and the second image is large based on the positional deviation information, Based on the determination result obtained in the first determination step, the acquisition step re-acquires the first image or the second image.

A fourteenth aspect of the embodiment, in any one of the ninth to thirteenth aspects, includes a quality evaluation step of calculating a quality evaluation value of at least one of the plurality of images.

A fifteenth aspect of the embodiment is the fourteenth aspect, comprising a second determination step of determining whether the quality of the plurality of images is good or bad based on the evaluation value, and based on the determination result obtained in the second determination step Then, the acquiring step reacquires at least one of the plurality of images or all of the plurality of images.

A sixteenth aspect of the embodiments is a program that causes a computer to execute each step of the ophthalmologic information processing method according to any one of the ninth to fifteenth aspects.

Note that it is possible to arbitrarily combine the configurations according to the plurality of aspects described above.

According to the present invention, it is possible to provide a new technique for more easily and highly accurately aligning spectral images.

It is a schematic diagram showing an example of the configuration of the optical system of the ophthalmologic apparatus according to the embodiment. It is a schematic diagram showing an example of the configuration of the optical system of the ophthalmologic apparatus according to the embodiment. 1 is a schematic diagram showing an example of the configuration of a control system of an ophthalmologic apparatus according to an embodiment; FIG. 1 is a schematic diagram showing an example of the configuration of a control system of an ophthalmologic apparatus according to an embodiment; FIG. 1 is a schematic diagram showing an example of the configuration of a control system of an ophthalmologic apparatus according to an embodiment; FIG. 1 is a schematic diagram showing an example of the configuration of a control system of an ophthalmologic apparatus according to an embodiment; FIG. 4 is a flow chart showing an example of the operation of the ophthalmologic apparatus according to the embodiment; 4 is a flow chart showing an example of the operation of the ophthalmologic apparatus according to the embodiment; 4 is a flow chart showing an example of the operation of the ophthalmologic apparatus according to the embodiment;

Exemplary embodiments of an ophthalmologic information processing apparatus, an ophthalmologic apparatus, an ophthalmologic information processing method, and a program according to the present invention will be described in detail with reference to the drawings. In addition, in the embodiments, it is possible to arbitrarily incorporate the techniques described in the documents cited in this specification.

An ophthalmologic information processing apparatus according to an embodiment obtains a plurality of spectral images of an eye to be examined over a predetermined analysis wavelength range, and performs optical coherence tomography (OCT) on the eye to be examined. Based on the obtained OCT data, a plurality of acquired spectral images are aligned.

A plurality of spectral images are obtained by illuminating the fundus (posterior segment) or the anterior segment of the eye to be inspected with illumination light, and sequentially receiving the return light of the illumination light from the eye to be inspected, which has different wavelength ranges in a predetermined analysis wavelength region. It is obtained by A spectral image is an example of a two-dimensional spectral distribution. Regarding the first returned light and the second returned light whose wavelength ranges are adjacent to each other among the sequentially received returned lights, part of the wavelength range of the first returned light may overlap with the wavelength range of the second returned light. Spectral images include hyperspectral images, multispectral images, and RGB color images.

In some embodiments, the subject's eye is sequentially illuminated with illumination light having two or more wavelength components whose wavelength ranges are different from each other, and return light having wavelength components in a predetermined wavelength range is sequentially emitted from the return light from the subject's eye. A plurality of spectral images are acquired by selecting .

In some embodiments, illumination light having wavelength components in a predetermined wavelength range is sequentially selected from illumination light having two or more wavelength components whose wavelength ranges are different from each other, and the eye to be examined is sequentially illuminated with the selected illumination light. A plurality of spectroscopic images are acquired by illuminating and sequentially receiving the return light from the subject's eye.

In some embodiments, illumination light having two or more wavelength components with mutually different wavelength ranges is sequentially emitted using a light source whose wavelength range can be arbitrarily changed, and the emitted illumination light sequentially illuminates the subject's eye. A plurality of spectroscopic images are acquired by illuminating and sequentially receiving the return light from the subject's eye.

In some embodiments, a plurality of spectroscopic images are obtained by illuminating the eye to be inspected with illumination light, sequentially changing the wavelength range in which the light receiving device has high light receiving sensitivity, and sequentially selecting the return light from the eye to be inspected. be done.

The OCT data may be a detection result of interference light, a B-scan image, or an en-face image obtained by performing OCT on the subject's eye. The interference light is obtained by dividing the light from the OCT light source into measurement light and reference light, projecting the measurement light onto the eye to be examined, and combining the return light of the measurement light from the eye to be examined and the reference light that has passed through the reference optical path. Generated by interfering. In some embodiments, the ophthalmic information processing device is configured to acquire OCT data obtained by an externally provided OCT device. In some embodiments, the functionality of the ophthalmic information processing device is implemented by an ophthalmic device capable of acquiring OCT data.

Alignment according to some embodiments is accomplished by changing the relative positions of multiple spectral images. Alignment according to some embodiments is realized by performing affine transformation or Helmert transformation on spectral images to be aligned based on a reference image. Examples of reference images include OCT images (eg, B-scan images, en-face images) formed based on OCT data.

This makes it possible to easily compare spectral characteristics between spectral images even when fixation dislocation and misalignment between the subject's eye and the imaging unit occur while a plurality of spectral images are being acquired. . In particular, by aligning based on OCT data, it is possible to align spectroscopic images with high accuracy based on information in the depth direction of the eye (depth direction). It is possible to improve the accuracy of spectroscopic analysis.

An ophthalmologic information processing method according to an embodiment includes one or more steps executed by the ophthalmologic information processing apparatus described above. A program according to an embodiment causes a computer (processor) to execute each step of an ophthalmologic information processing method according to an embodiment. A recording medium according to the embodiment is a non-temporary recording medium (storage medium) in which the program according to the embodiment is recorded.

In this specification, the processor includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (e.g., SPLD (Simple Programmable Logic Device), CPLD Logic Device), FPGA (Field Programmable Gate Array)) and other circuits. The processor implements the functions according to the embodiment by, for example, reading and executing a program stored in a memory circuit or memory device. A memory circuit or device may be included in the processor. Also, a memory circuit or memory device may be provided external to the processor.

A case in which alignment is performed with respect to a spectral image of the fundus of the subject's eye (spectral fundus image) will be described below, but the configuration according to the embodiment is not limited to this. For example, the following embodiments can also be applied to a case where alignment is performed with respect to a spectral image of an anterior segment other than the fundus (spectral anterior segment image).

In some embodiments, the ophthalmologic information processing apparatus is configured to acquire spectroscopic images of the eye to be examined that are acquired externally through a communication function. In some embodiments, an ophthalmologic apparatus capable of acquiring a spectroscopic image of an eye to be examined has the function of an ophthalmologic information processing apparatus.

In the following embodiments, an ophthalmologic apparatus including the functions of the ophthalmologic information processing apparatus according to the embodiment will be described as an example. An ophthalmologic apparatus according to an embodiment includes an ophthalmologic imaging apparatus. The ophthalmic imaging device included in the ophthalmic device of some embodiments is, for example, any one or more of a fundus camera, a scanning optical ophthalmoscope, a slit lamp ophthalmoscope, a surgical microscope, or the like. An ophthalmic device according to some embodiments includes any one or more of an ophthalmic measurement device and an ophthalmic treatment device in addition to an ophthalmic imaging device. The ophthalmic measurement device included in the ophthalmic device of some embodiments is, for example, any one or more of an eye refractor, a tonometer, a specular microscope, a wavefront analyzer, a perimeter, a microperimeter, etc. . The ophthalmic treatment device included in the ophthalmic device of some embodiments is, for example, any one or more of a laser treatment device, a surgical device, a surgical microscope, and the like.

In the following embodiments, the ophthalmic device includes an optical coherence tomography and a fundus camera. Although swept source OCT is applied to this optical coherence tomography, the type of OCT is not limited to this, and other types of OCT (spectral domain OCT, time domain OCT, Amphas OCT, etc.) may be applied. good.

Hereinafter, the x direction is the direction (horizontal direction) orthogonal to the optical axis direction of the objective lens, and the y direction is the direction (vertical direction) orthogonal to the optical axis direction of the objective lens. The z-direction is assumed to be the optical axis direction of the objective lens.

<Configuration>
〔Optical system〕
As shown in FIG. 1 , the ophthalmologic apparatus 1 includes a fundus camera unit 2 , an OCT unit 100 and an arithmetic control unit 200 . The retinal camera unit 2 is provided with an optical system and a mechanism for acquiring a front image of the eye E to be examined. The OCT unit 100 is provided with a part of an optical system and a mechanism for performing OCT. Another part of the optical system and mechanism for performing OCT is provided in the fundus camera unit 2 . The arithmetic control unit 200 includes one or more processors that perform various arithmetic operations and controls. In addition to these, arbitrary elements such as a member for supporting the subject's face (chin rest, forehead rest, etc.) and a lens unit for switching the target part of OCT (for example, attachment for anterior segment OCT) or unit may be provided in the ophthalmologic apparatus 1 . Furthermore, the ophthalmologic apparatus 1 includes a pair of anterior eye cameras 5A and 5B.

[Fundus camera unit 2]
The fundus camera unit 2 is provided with an optical system for photographing the fundus Ef of the eye E to be examined. The acquired image of the fundus oculi Ef (referred to as a fundus image, fundus photograph, etc.) is a front image such as an observed image or a photographed image. Observation images are obtained by moving image shooting using near-infrared light. The captured image is a still image using flash light or a spectral image (spectral fundus image, spectral anterior segment image). Furthermore, the fundus camera unit 2 can photograph the anterior segment Ea of the subject's eye E to acquire a front image (anterior segment image).

The fundus camera unit 2 includes an illumination optical system 10 and an imaging optical system 30 . The illumination optical system 10 irradiates the eye E to be inspected with illumination light. The imaging optical system 30 detects return light of the illumination light from the eye E to be examined. The measurement light from the OCT unit 100 is guided to the subject's eye E through the optical path in the retinal camera unit 2, and its return light is guided to the OCT unit 100 through the same optical path.

Light (observation illumination light) output from an observation light source 11 of an illumination optical system 10 is reflected by a reflecting mirror 12 having a curved reflecting surface, passes through a condenser lens 13, and passes through a visible light cut filter 14. It becomes near-infrared light. Furthermore, the observation illumination light is once converged near the photographing light source 15 , reflected by the mirror 16 , and passed through the relay lenses 17 and 18 , the diaphragm 19 and the relay lens 20 . Then, the observation illumination light is reflected by the periphery of the perforated mirror 21 (area around the perforation), passes through the dichroic mirror 46, is refracted by the objective lens 22, Illuminate part Ea). The return light of the observation illumination light from the subject's eye E is refracted by the objective lens 22, passes through the dichroic mirror 46, passes through the hole formed in the central region of the aperture mirror 21, and passes through the photographing focusing lens 31. through and reflected by mirror 32 . Further, this return light passes through the half mirror 33A, is reflected by the dichroic mirror 33, and is imaged on the light receiving surface of the image sensor 35 by the condenser lens . The image sensor 35 detects returned light at a predetermined frame rate. The focus of the imaging optical system 30 is adjusted so as to match the fundus oculi Ef or the anterior segment Ea.

The light (imaging illumination light) output from the imaging light source 15 irradiates the fundus oculi Ef through the same path as the observation illumination light. The return light of the photographing illumination light from the subject's eye E is guided to the dichroic mirror 33 through the same path as the return light of the observation illumination light, passes through the dichroic mirror 33, is reflected by the mirror 36, and enters the tunable filter 80. be guided.

The wavelength tunable filter 80 is a filter that can select the wavelength range of transmitted light in a predetermined analysis wavelength region. The wavelength range of light transmitted through the wavelength tunable filter 80 can be arbitrarily selected.

In some embodiments, the tunable filter 80 is similar to, for example, the liquid crystal tunable filter disclosed in JP-A-2006-158546. In this case, the wavelength tunable filter 80 can arbitrarily select the wavelength selection range of transmitted light by changing the voltage applied to the liquid crystal.

In some embodiments, the wavelength tunable filter 80 includes two or more wavelength selection filters having different wavelength selection ranges for transmitted light, and the two or more wavelength selection filters are selectively arranged in the optical path of return light of the illumination light. may be configured to be possible.

In some embodiments, the tunable filter 80 is a filter that can select the wavelength range of reflected light in a given analysis wavelength region.

Return light from the mirror 36 that has passed through the wavelength tunable filter 80 is imaged on the light receiving surface of the image sensor 38 by the condenser lens 37 .

In some embodiments, tunable filter 80 is positioned between dichroic mirror 33 and condenser lens 34 .

In some embodiments, the wavelength tunable filter 80 is configured to be insertable and removable with respect to the optical path between the dichroic mirror 33 or mirror 36 and the condenser lens 37 . For example, when the wavelength tunable filter 80 is arranged in the optical path between the dichroic mirror 33 and the condenser lens 37, the ophthalmologic apparatus 1 can sequentially obtain the results of receiving the returned light obtained by the image sensor 38. Multiple spectral fundus images can be acquired. For example, when the wavelength tunable filter 80 is retracted from the optical path between the dichroic mirror 33 and the condenser lens 37, the ophthalmologic apparatus 1 obtains the result of receiving the return light obtained by the image sensor 38, and normally still images (fundus image, anterior segment image) can be acquired.

An image (observation image) based on the fundus reflected light detected by the image sensor 35 is displayed on the display device 3 . Note that when the imaging optical system 30 is focused on the anterior segment, an observation image of the anterior segment of the subject's eye E is displayed. The display device 3 also displays an image (captured image, spectral fundus image) based on the fundus reflected light detected by the image sensor 38 . The display device 3 that displays the observed image and the display device 3 that displays the captured image may be the same or different. When the subject's eye E is illuminated with infrared light and photographed in the same manner, an infrared photographed image is displayed.

An LCD (Liquid Crystal Display) 39 displays a fixation target and visual acuity measurement target. A part of the light flux output from the LCD 39 is reflected by the half mirror 33 A, reflected by the mirror 32 , passes through the photographing focusing lens 31 , and passes through the aperture of the apertured mirror 21 . The luminous flux that has passed through the aperture of the perforated mirror 21 is transmitted through the dichroic mirror 46, refracted by the objective lens 22, and projected onto the fundus oculi Ef.

By changing the display position of the fixation target on the screen of the LCD 39, the fixation position of the subject's eye E can be changed. Examples of fixation positions include the fixation position for acquiring an image centered on the macula, the fixation position for acquiring an image centered on the optic disc, and the center of the fundus between the macula and the optic disc. and a fixation position for acquiring an image of a site far away from the macula (eye fundus periphery). The ophthalmologic apparatus 1 according to some embodiments includes a GUI (Graphical User Interface) or the like for designating at least one of such fixation positions. The ophthalmologic apparatus 1 according to some embodiments includes a GUI or the like for manually moving the fixation position (the display position of the fixation target).

The configuration for presenting a movable fixation target to the subject's eye E is not limited to a display device such as an LCD. For example, a movable fixation target can be generated by selectively lighting multiple light sources in a light source array (such as a light emitting diode (LED) array). Also, one or more movable light sources can generate a movable fixation target.

The focus optical system 60 generates a split index used for focus adjustment of the eye E to be examined. The focus optical system 60 is moved along the optical path (illumination optical path) of the illumination optical system 10 in conjunction with the movement of the imaging focusing lens 31 along the optical path (illumination optical path) of the imaging optical system 30 . The reflecting bar 67 can be inserted into and removed from the illumination optical path. When performing focus adjustment, the reflecting surface of the reflecting bar 67 is arranged at an angle in the illumination optical path. Focus light output from the LED 61 passes through a relay lens 62, is split into two light beams by a split index plate 63, passes through a two-hole diaphragm 64, is reflected by a mirror 65, and is reflected by a condenser lens 66 onto a reflecting rod 67. is once imaged on the reflective surface of , and then reflected. Further, the focused light passes through the relay lens 20, is reflected by the perforated mirror 21, passes through the dichroic mirror 46, is refracted by the objective lens 22, and is projected onto the fundus oculi Ef. The fundus reflected light of the focus light is guided to the image sensor 35 through the same path as the return light of the observation illumination light. Manual focus and autofocus can be performed based on the received light image (split index image).

The dichroic mirror 46 synthesizes the fundus imaging optical path and the OCT optical path. The dichroic mirror 46 reflects light in the wavelength band used for OCT and transmits light for fundus imaging. The optical path for OCT (the optical path of the measurement light) includes, in order from the OCT unit 100 side toward the dichroic mirror 46 side, a collimator lens unit 40, an optical path length changing section 41, an optical scanner 42, an OCT focusing lens 43, a mirror 44, and a relay lens 45 are provided.

The optical path length changing unit 41 is movable in the direction of the arrow shown in FIG. 1, and changes the length of the optical path for OCT. This change in optical path length is used for optical path length correction according to the axial length of the eye, adjustment of the state of interference, and the like. The optical path length changing section 41 includes a corner cube and a mechanism for moving it.

The optical scanner 42 is arranged at a position optically conjugate with the pupil of the eye E to be examined. The optical scanner 42 deflects the measurement light LS passing through the OCT optical path. The optical scanner 42 is, for example, a galvanometer scanner capable of two-dimensional scanning.

The OCT focusing lens 43 is moved along the optical path of the measurement light LS in order to focus the optical system for OCT. Movement of the imaging focusing lens 31, movement of the focusing optical system 60, and movement of the OCT focusing lens 43 can be controlled in a coordinated manner.

[Anterior segment cameras 5A and 5B]
The anterior eye cameras 5A and 5B are used to determine the relative position between the optical system of the ophthalmologic apparatus 1 and the subject's eye E, similar to the invention disclosed in Japanese Patent Laid-Open No. 2013-248376. The anterior eye cameras 5A and 5B are provided on the face of the subject's eye E side of a housing (fundus camera unit 2, etc.) housing an optical system. The ophthalmologic apparatus 1 analyzes two anterior eye images obtained substantially simultaneously from different directions by the anterior eye cameras 5A and 5B, thereby determining the three-dimensional relative relationship between the optical system and the subject's eye E. find the position. The analysis of the two anterior segment images may be similar to the analysis disclosed in Japanese Patent Application Laid-Open No. 2013-248376. Also, the number of anterior segment cameras may be any number of two or more.

In this example, the position of the eye to be examined E (that is, the relative position between the eye to be examined E and the optical system) is obtained using two or more anterior eye cameras. It is not limited to this. For example, the position of the eye E to be examined can be obtained by analyzing a front image of the eye E to be examined (for example, an observed image of the anterior segment Ea). Alternatively, means for projecting an index onto the cornea of the subject's eye E can be provided, and the position of the subject's eye E can be obtained based on the projection position of this index (that is, the detection state of the corneal reflected light flux of this index).

[OCT unit 100]
As illustrated in FIG. 2, the OCT unit 100 is provided with an optical system for performing swept-source OCT. This optical system includes an interference optical system. This interference optical system has a function of dividing light from a wavelength tunable light source (wavelength swept light source) into measurement light and reference light, return light of the measurement light from the subject's eye E, and reference light passing through the reference light path. and a function of generating interference light and a function of detecting this interference light. A detection result (detection signal) of the interference light obtained by the interference optical system is a signal indicating the spectrum of the interference light, and is sent to the arithmetic control unit 200 .

The light source unit 101 includes, for example, a near-infrared tunable laser that changes the wavelength of emitted light at high speed. The light L0 output from the light source unit 101 is guided to the polarization controller 103 by the optical fiber 102, and the polarization state is adjusted. The light L0 whose polarization state has been adjusted is guided by the optical fiber 104 to the fiber coupler 105 and split into the measurement light LS and the reference light LR.

The reference light LR is guided to the collimator 111 by the optical fiber 110 and converted into a parallel beam, and guided to the corner cube 114 via the optical path length correction member 112 and the dispersion compensation member 113 . The optical path length correction member 112 acts to match the optical path length of the reference light LR and the optical path length of the measurement light LS. The dispersion compensation member 113 acts to match the dispersion characteristics between the reference light LR and the measurement light LS. The corner cube 114 is movable in the incident direction of the reference light LR, thereby changing the optical path length of the reference light LR.

The reference light LR that has passed through the corner cube 114 passes through the dispersion compensating member 113 and the optical path length correcting member 112 , is converted by the collimator 116 from a parallel beam to a converged beam, and enters the optical fiber 117 . The reference light LR incident on the optical fiber 117 is guided to the polarization controller 118 to have its polarization state adjusted, guided to the attenuator 120 via the optical fiber 119 to have its light amount adjusted, and guided to the fiber coupler 122 via the optical fiber 121 . be killed.

On the other hand, the measurement light LS generated by the fiber coupler 105 is guided by the optical fiber 127 and converted into a parallel light beam by the collimator lens unit 40, and the optical path length changing unit 41, the optical scanner 42, the OCT focusing lens 43, and the mirror 44. and relay lens 45 . The measurement light LS that has passed through the relay lens 45 is reflected by the dichroic mirror 46, refracted by the objective lens 22, and enters the eye E to be examined. The measurement light LS is scattered and reflected at various depth positions of the eye E to be examined. The return light of the measurement light LS from the subject's eye E travels in the opposite direction along the same path as the forward path, is guided to the fiber coupler 105 , and reaches the fiber coupler 122 via the optical fiber 128 . It should be noted that the incident length of the optical fiber 127 into which the measurement light LS is incident is arranged at a position substantially conjugate with the fundus oculi Ef of the eye E to be examined.

The fiber coupler 122 combines (interferences) the measurement light LS that has entered via the optical fiber 128 and the reference light LR that has entered via the optical fiber 121 to generate interference light. The fiber coupler 122 generates a pair of interference lights LC by splitting the interference lights at a predetermined splitting ratio (for example, 1:1). A pair of interference lights LC are guided to detector 125 through optical fibers 123 and 124, respectively.

Detector 125 is, for example, a balanced photodiode. A balanced photodiode includes a pair of photodetectors that respectively detect a pair of interference lights LC, and outputs a difference between a pair of detection results obtained by these photodetectors. The detector 125 sends this output (detection signal) to a DAQ (Data Acquisition System) 130 .

A clock KC is supplied from the light source unit 101 to the DAQ 130 . The clock KC is generated in the light source unit 101 in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the wavelength tunable light source. The light source unit 101, for example, optically delays one of the two branched lights obtained by branching the light L0 of each output wavelength, and then outputs the clock KC based on the result of detecting these combined lights. Generate. The DAQ 130 samples the detection signal input from the detector 125 based on the clock KC. DAQ 130 sends the sampling result of the detection signal from detector 125 to arithmetic control unit 200 .

In this example, an optical path length changing unit 41 for changing the length of the optical path (measurement optical path, measurement arm) of the measurement light LS and an optical path length changing unit 41 for changing the length of the optical path (reference optical path, reference arm) of the reference light LR corner cubes 114 are provided. However, only one of the optical path length changing portion 41 and the corner cube 114 may be provided. It is also possible to change the difference between the measurement optical path length and the reference optical path length by using optical members other than these.

[Control system]
3 to 6 show configuration examples of the control system of the ophthalmologic apparatus 1. FIG. 3 to 6, some of the components included in the ophthalmologic apparatus 1 are omitted. In FIG. 3, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted as appropriate. The control section 210, the image forming section 220 and the data processing section 230 are provided in the arithmetic control unit 200, for example.

<Control unit 210>
The control unit 210 executes various controls. Control unit 210 includes main control unit 211 and storage unit 212 .

<Main control unit 211>
The main controller 211 includes a processor (eg, control processor) and controls each part of the ophthalmologic apparatus 1 (including each element shown in FIGS. 1 to 6). For example, the main control unit 211 controls each part of the optical system of the retinal camera unit 2 shown in FIGS. It controls mechanism 150 , image forming section 220 , data processing section 230 and user interface (UI) 240 .

The control over the retinal camera unit 2 includes control over the focus driving units 31A and 43A, control over the wavelength tunable filter 80, control over the image sensors 35 and 38, control over the optical path length changing unit 41, and control over the optical scanner 42. be

The control for the focus drive unit 31A includes control for moving the photographing focus lens 31 in the optical axis direction. The control for the focus drive unit 43A includes control for moving the OCT focus lens 43 in the optical axis direction.

Control over the wavelength tunable filter 80 includes selective control of the wavelength range of transmitted light (for example, control of voltage applied to liquid crystal).

The control of the image sensors 35 and 38 includes control of the light receiving sensitivity of the imaging element, control of the frame rate (light receiving timing, exposure time), control of the light receiving area (position, size, size), and readout of the light receiving result of the imaging element. control, etc. In some embodiments, by changing the exposure time according to the wavelength range of the return light, the image sensor is arranged so that the received light intensity is uniform in each wavelength range of the analysis wavelength range in which a plurality of spectral fundus images are acquired. 35, 38 are controlled. In some embodiments, the main controller 211 controls the wavelength components of the illumination light in each wavelength range so that the received light intensity is uniform in each wavelength range of the analysis wavelength range in which a plurality of spectral fundus images are acquired. to control the intensity of the

Control over the LCD 39 includes control of the fixation position. For example, the main control unit 211 displays the fixation target at a position on the screen of the LCD 39 corresponding to the fixation position set manually or automatically. Further, the main control unit 211 can change (continuously or stepwise) the display position of the fixation target displayed on the LCD 39 . Thereby, the fixation target can be moved (that is, the fixation position can be changed). The display position and movement mode of the fixation target are set manually or automatically. Manual setting is performed using, for example, a GUI. Automatic setting is performed by the data processing unit 230, for example.

Control over the optical path length changing unit 41 includes control for changing the optical path length of the measurement light LS. The main control unit 211 moves the optical path length changing unit 41 along the optical path of the measuring light LS by controlling the driving unit that drives the corner cubes of the optical path length changing unit 41 to change the optical path length of the measuring light LS. .

Control of the optical scanner 42 includes control of scan mode, scan range (scan start position, scan end position), scan speed, and the like. By controlling the optical scanner 42, the main control unit 211 can perform an OCT scan with the measurement light LS on a desired region of the measurement site (imaging site).

The main control unit 211 also controls the observation light source 11, the photographing light source 15, the focus optical system 60, and the like.

Control over the OCT unit 100 includes control over the light source unit 101, control over the reference driver 114A, control over the detector 125, and control over the DAQ .

The control of the light source unit 101 includes control of turning on and off of the light source, control of the amount of light emitted from the light source, control of the wavelength sweep range, wavelength sweep speed, control of emission timing of light of each wavelength component, and the like. .

Control over the reference driver 114A includes control to change the optical path length of the reference light LR. The main control unit 211 moves the corner cube 114 along the optical path of the reference light LR by controlling the reference driving unit 114A to change the optical path length of the reference light LR.

Control of the detector 125 includes control of the light receiving sensitivity of the detection element, control of the frame rate (light receiving timing), control of the light receiving area (position, size, size), control of readout of the light receiving result of the detection element, and the like.

The control over the DAQ 130 includes fetch control (fetch timing, sampling timing) of the detection result of the interference light obtained by the detector 125, readout control of the interference signal corresponding to the detection result of the fetched interference light, and the like.

Control of the anterior eye cameras 5A and 5B includes control of the light receiving sensitivity of each camera, frame rate (light receiving timing) control, synchronization control of the anterior eye cameras 5A and 5B, and the like.

The moving mechanism 150, for example, three-dimensionally moves at least the retinal camera unit 2 (optical system). In a typical example, the movement mechanism 150 includes at least a mechanism for moving the retinal camera unit 2 in the x direction (horizontal direction), a mechanism for moving it in the y direction (vertical direction), and a mechanism for moving it in the z direction (depth direction). , back and forth). The mechanism for moving in the x-direction includes, for example, an x-stage movable in the x-direction and an x-moving mechanism for moving the x-stage. The mechanism for moving in the y-direction includes, for example, a y-stage movable in the y-direction and a y-moving mechanism for moving the y-stage. The mechanism for moving in the z-direction includes, for example, a z-stage movable in the z-direction and a z-moving mechanism for moving the z-stage. Each movement mechanism includes a pulse motor as an actuator and operates under control from the main control unit 211 .

Control over the moving mechanism 150 is used in alignment and tracking. Tracking is to move the apparatus optical system according to the eye movement of the eye E to be examined. Alignment and focus adjustment are performed in advance when tracking is performed. Tracking is a function of maintaining a suitable positional relationship in which alignment and focus are achieved by causing the position of the apparatus optical system to follow the movement of the eyeball. Some embodiments are configured to control movement mechanism 150 to change the optical path length of the reference beam (and thus the optical path length difference between the optical path of the measurement beam and the optical path of the reference beam).

In the case of manual alignment, the user relatively moves the optical system and the subject's eye E by operating the user interface 240 so that the displacement of the subject's eye E with respect to the optical system is cancelled. For example, the main control unit 211 controls the moving mechanism 150 to move the optical system relative to the eye E by outputting a control signal corresponding to the operation content of the user interface 240 to the moving mechanism 150 .

In the case of auto-alignment, the main control unit 211 controls the movement mechanism 150 so that the displacement of the eye E to be inspected with respect to the optical system is canceled so that the optical system is relatively moved with respect to the eye E to be inspected. Specifically, as described in JP-A-2013-248376, arithmetic processing using trigonometry based on the positional relationship between the pair of anterior eye cameras 5A and 5B and the subject's eye E is performed, and the main control unit A reference numeral 211 controls the moving mechanism 150 so that the eye to be examined E has a predetermined positional relationship with respect to the optical system. In some embodiments, the main controller 211 outputs a control signal such that the optical axis of the optical system substantially coincides with the axis of the eye E to be examined and the distance of the optical system from the eye E to be examined is a predetermined working distance. to the moving mechanism 150 to control the moving mechanism 150 to move the optical system relative to the eye E to be examined. Here, the working distance is a default value also called a working distance of the objective lens 22, and corresponds to the distance between the subject's eye E and the optical system at the time of measurement (at the time of photographing) using the optical system.

The main control unit 211 can display various information on the display unit 240A as a display control unit. For example, the main control unit 211 causes the display unit 240A to display a plurality of spectral fundus images in association with wavelength ranges. For example, the main control section 211 causes the display section 240A to display the analysis processing result obtained by the analysis section 232 .

<Storage unit 212>
The storage unit 212 stores various data. The function of the storage unit 212 is implemented by a storage device such as a memory or a storage device. Examples of data stored in the storage unit 212 include control parameters, fundus image data, anterior segment image data, OCT data (including OCT images), fundus spectral image data, and anterior segment image. spectroscopic image data, information on the eye to be examined, and the like. Control parameters include hyperspectral imaging control data and the like. The hyperspectral imaging control data is control data for acquiring a plurality of fundus images based on return light beams having different central wavelengths within a predetermined analysis wavelength range. Examples of hyperspectral imaging control data include an analysis wavelength range in which a plurality of spectral fundus images are acquired, a wavelength range in which each spectral fundus image is acquired, a center wavelength, a center wavelength step, and a wavelength tunable filter 80 corresponding to the center wavelength. control data, etc. The eye information to be examined includes information about the subject such as patient ID and name, information about the eye to be examined such as left/right eye identification information, and electronic medical record information. The storage unit 212 stores programs for executing various processors (control processor, image forming processor, data processing processor).

<Image forming unit 220>
The image forming unit 220 includes a processor (for example, an image forming processor), and forms an OCT image (image data) of the subject's eye E based on the output from the DAQ 130 (sampling result of the detection signal). For example, the image forming unit 220 performs signal processing on the spectral distribution based on the sampling result for each A line, forms a reflection intensity profile for each A line, and images these A line profiles as in the conventional swept source OCT. and arrange them along the scan lines. The signal processing includes noise removal (noise reduction), filtering, FFT (Fast Fourier Transform), and the like. When performing another type of OCT, the image forming section 220 performs known processing according to that type.

<Data processing unit 230>
The data processing unit 230 includes a processor (for example, a data processing processor) and performs image processing and analysis processing on the image formed by the image forming unit 220 . At least two of the processor included in the main control unit 211, the processor included in the data processing unit 230, and the processor included in the image forming unit 220 may be configured by a single processor.

The data processing unit 230 executes known image processing such as interpolation processing for interpolating pixels between tomographic images to form image data of a three-dimensional image of the fundus oculi Ef or the anterior segment Ea. Note that image data of a three-dimensional image means image data in which pixel positions are defined by a three-dimensional coordinate system. Image data of a three-dimensional image includes image data composed of voxels arranged three-dimensionally. This image data is called volume data or voxel data. When displaying an image based on volume data, the data processing unit 230 performs rendering processing (volume rendering, MIP (Maximum Intensity Projection: maximum intensity projection), etc.) on this volume data so that it can be viewed from a specific line-of-sight direction. Image data of a pseudo three-dimensional image is formed. This pseudo three-dimensional image is displayed on a display device such as the display unit 240A.

Stack data of a plurality of tomographic images can also be formed as image data of a three-dimensional image. Stacked data is image data obtained by three-dimensionally arranging a plurality of tomographic images obtained along a plurality of scan lines based on the positional relationship of the scan lines. That is, stack data is image data obtained by expressing a plurality of tomographic images, which were originally defined by individual two-dimensional coordinate systems, by one three-dimensional coordinate system (that is, embedding them in one three-dimensional space). be.

In some embodiments, data processor 230 generates a B-scan image by arranging the A-scan image in the B-scan direction. In some embodiments, the data processing unit 230 performs various renderings on the acquired three-dimensional data set (volume data, stack data, etc.) to obtain a B-mode image (B-scan image) (longitudinal section) in an arbitrary cross section. plane image, axial cross-sectional image), C-mode image (C-scan image) at an arbitrary cross-section (cross-sectional image, horizontal cross-sectional image), projection image, shadowgram, and the like. An arbitrary cross-sectional image, such as a B-scan image or a C-scan image, is formed by selecting pixels (pixels, voxels) on a specified cross-section from a three-dimensional data set. A projection image is formed by projecting a three-dimensional data set in a predetermined direction (z direction, depth direction, axial direction). A shadowgram is formed by projecting a portion of the three-dimensional data set (for example, partial data corresponding to a specific layer) in a predetermined direction. By changing the depth range in the layer direction to be integrated, it is possible to form two or more different shadowgrams. An image such as a C-scan image, a projection image, or a shadowgram whose viewpoint is the front side of the subject's eye is called an en-face image.

The data processing unit 230 generates B-scan images and front images (blood vessel-enhanced images, angiograms) in which retinal vessels and choroidal vessels are emphasized based on data (for example, B-scan image data) collected in time series by OCT. can be constructed. For example, time-series OCT data can be collected by repeatedly scanning substantially the same portion of the eye E to be examined.

In some embodiments, the data processing unit 230 compares time-series B-scan images obtained by B-scans of substantially the same site, and converts the pixel values of the portions where the signal intensity changes to the pixel values corresponding to the changes. An enhanced image in which the changed portion is emphasized is constructed by the conversion. Furthermore, the data processing unit 230 extracts information for a predetermined thickness in a desired region from the constructed multiple enhanced images and constructs an en-face image to form an OCTA image.

Such a data processing section 230 includes an alignment processing section 231 and an analysis section 232 .

<Alignment processing unit 231>
The alignment processing unit 231 calculates positions of a plurality of spectral fundus images of the subject eye E corresponding to a plurality of wavelength ranges within a predetermined analysis wavelength range based on OCT data obtained by performing OCT on the subject eye E. perform alignment.

The OCT data may be a detection result of interference light, a B-scan image, or an en-face image obtained by performing OCT on the subject's eye.

Since the relative position of the optical axis of the OCT unit 100 with respect to the optical axis of the imaging optical system 30 is known, the OCT scanning position using the OCT unit 100 (or the OCT image inside) can be specified.

In addition, the fundus oculi Ef is composed of a plurality of layer regions having different characteristics with respect to wavelength components of incident light. That is, the plurality of layer regions differ in the proportion of reflected light, the proportion of absorbed light, and the proportion of transmitted light according to the wavelength component of incident light. Specifically, in the analysis wavelength range, the shorter the wavelength, the stronger the intensity of the reflected light from the surface layer (nerve fiber layer). It is known that the intensity of reflected light in the deeper layer (choroid layer) increases as the depth increases. Therefore, the layer region of the fundus oculi Ef can be associated in advance with the wavelength range of light incident on the fundus oculi Ef.

Therefore, the alignment processing unit 231 uses the detection result of the interference light obtained by OCT scanning the position corresponding to the characteristic part (characteristic region, characteristic point) in the spectral fundus image to obtain a plurality of spectral fundus images. are aligned. The characteristic site is specified by, for example, the analysis unit 232 described later. For example, the alignment processing unit 231 aligns the first layer region and the second layer of the fundus oculi Ef from the first depth position (z position) and the second depth position where the intensity of the interference light is high based on the detection result of the interference light. Identify areas. The alignment processing unit 231 aligns the first spectral fundus image corresponding to the specified first layer region and the second spectral fundus image corresponding to the specified second layer region in the xy direction.

In some embodiments, the alignment processing unit 231 aligns multiple spectral fundus images using B-scan images that pass through positions corresponding to characteristic regions in the spectral fundus images. For example, the registration processing unit 231 specifies the first layer region and the second layer region of the fundus oculi Ef at the first depth position and the second depth position by performing known segmentation processing on the B-scan image. . The alignment processing unit 231 aligns the first spectral fundus image corresponding to the specified first layer region and the second spectral fundus image corresponding to the specified second layer region in the xy direction.

In some embodiments, the alignment processing unit 231 aligns a plurality of spectral fundus images using an en-face image that depicts one or more characteristic regions in the spectral fundus images. For example, the alignment processing unit 231 aligns the positions of one or more characteristic regions in the en-face image with the positions of the characteristic regions of the plurality of spectral fundus images. For example, the alignment processing unit 231 performs least squares matching (LSM) on one or more characteristic regions in each of the en-face image and the spectral fundus image to be aligned, and calculates the difference in gradation between the two images. Align the two images so that the sum of squares is minimized. In some embodiments, the alignment processing unit 231 aligns the spectral fundus image with the en-face image by performing affine transformation or Helmert transformation on the spectral fundus image to be aligned.

In some embodiments, the alignment processing unit 231 aligns the spectral fundus images using a different reference image for each wavelength range (for each depth position in the fundus). The different reference images for different wavelength ranges may be, for example, shadowgrams (en-face images with different depth positions, C-scan images) with different integration ranges depending on the wavelength ranges.

In some embodiments, the alignment processing unit 231 aligns each spectroscopic fundus image with a different OCT front image (en-face image, C-scan image). The OCT front image may be an image that has the highest degree of correlation with the spectral fundus image to be registered.

Here, the spectroscopic fundus image is formed based on return light from various depth positions. As a result, each of the plurality of spectral fundus images has characteristics of changes in intensity of return light from different depth positions for each wavelength range. Therefore, the spectral fundus image can be easily aligned with the OCT front image of the depth position (layer area) corresponding to the spectral fundus image. For example, in the wavelength range up to 600 nm, the retinal vessels become sharper, in the wavelength range from 620 nm to 690 nm, the optic disc becomes sharper, and in the wavelength range above 660 nm, the choroidal vessels become sharper. Therefore, the alignment processing unit 231 aligns the spectral fundus images with reference to the OCT front image at the depth position corresponding to the wavelength range of the spectral fundus images, thereby performing the alignment of the spectral fundus images with high accuracy. Alignment becomes possible. For example, compared to the method of the comparative example in which position alignment is performed using spectral fundus images with a similar wavelength range, since the regions depicted in the spectral fundus images differ depending on the wavelength range, OCT has higher resolution in the depth direction than the spectral fundus images. Since the alignment is performed using the OCT front image formed based on the data, the spectral fundus images can be aligned with high accuracy.

<analysis unit 232>
As shown in FIG. 4, the analysis section 232 includes a characteristic part identification section 232A, a three-dimensional position calculation section 232B, a positional deviation processing section 232C, and an image quality processing section 232D. Either one of the positional deviation processing section 232C and the image quality processing section 232D may be omitted.

The analysis unit 232 can analyze an image (including a spectroscopic fundus image) of the subject's eye E to specify a characteristic region depicted in the image. For example, the analysis unit 232 obtains the three-dimensional position of the subject's eye E based on the positions of the anterior eye cameras 5A and 5B and the positions of the specified characteristic regions. The main control unit 211 aligns the optical system with respect to the eye to be examined E by relatively moving the optical system with respect to the eye to be examined E based on the determined three-dimensional position.

Further, the analysis unit 232 can identify characteristic regions used for alignment processing executed by the alignment processing unit 231 described above.

The analysis unit 232 can perform predetermined analysis processing on a plurality of spectral fundus images that have been aligned by the alignment processing unit 231 . Examples of predetermined analysis processing include comparison processing of arbitrary two images among a plurality of spectral fundus images, processing of extracting a common region or difference region specified by the comparison processing, and attention to at least one of the plurality of spectral fundus images. Part or characteristic part identification processing, identification display processing of the common region, the difference region, the target region, or the characteristic region in the spectral fundus image, at least two images out of the plurality of spectral fundus images , and the like.

<Characteristic part identification unit 232A>
The characteristic site identification unit 232A analyzes each of the captured images obtained by the anterior segment cameras 5A and 5B to identify positions (referred to as characteristic positions) in the captured images corresponding to the characteristic sites of the anterior segment Ea. Identify. For example, the pupil region of the subject eye E, the pupil center position of the subject eye E, the pupil center position, the corneal center position, the corneal vertex position, the subject eye center position, or the iris are used as the characteristic site. A specific example of processing for specifying the pupil center position of the eye E to be examined will be described below.

First, the characteristic part identification unit 232A identifies an image region (pupil region) corresponding to the pupil of the subject's eye E based on the distribution of pixel values (such as luminance values) of the captured image. Since the pupil is generally drawn with lower luminance than other parts, the pupil region can be identified by searching for the low-luminance image region. At this time, the pupil region may be specified in consideration of the shape of the pupil. In other words, the pupil region can be identified by searching for a substantially circular low-brightness image region.

Next, the characteristic part identifying section 232A identifies the central position of the identified pupil region. Since the pupil is substantially circular as described above, it is possible to specify the outline of the pupil region, specify the center position of this outline (the approximate circle or approximate ellipse), and set this as the pupil center position. Alternatively, the center of gravity of the pupil region may be obtained and the position of the center of gravity may be specified as the position of the center of gravity of the pupil.

It should be noted that even when specifying a characteristic position corresponding to another characteristic part, it is possible to specify the characteristic position based on the distribution of pixel values of the captured image in the same manner as described above.

The characteristic part identification unit 232A can sequentially identify characteristic positions corresponding to characteristic parts in the captured images sequentially obtained by the anterior eye cameras 5A and 5B. In addition, the characteristic site identifying section 232A may identify the characteristic position every one or more frames of the captured images sequentially obtained by the anterior eye cameras 5A and 5B.

Also, the characteristic site identification unit 232A can similarly identify the characteristic site for the spectral fundus image. In this case, the characteristic regions include a blood vessel region, a diseased region, a region characterized by a change in pixel brightness, and the like. A characteristic portion of the spectral fundus image may be designated using the operation section 240B of the user interface 240 .

<Three-dimensional position calculator 232B>
The three-dimensional position calculation unit 232B calculates the three-dimensional position of the characteristic part of the subject's eye E based on the positions of the anterior eye cameras 5A and 5B and the characteristic position corresponding to the characteristic part specified by the characteristic part specifying unit 232A. Identify as a three-dimensional position. The three-dimensional position calculation unit 232B, as disclosed in Japanese Unexamined Patent Application Publication No. 2013-248376, calculates the positions (known) of the two anterior eye cameras 5A and 5B and the characteristic regions in the two captured images. The three-dimensional position of the subject's eye E is calculated by applying a known trigonometric method to the position where the eye E is to be examined. The three-dimensional position calculated by the three-dimensional position calculator 232B is sent to the main controller 211. FIG. Based on the three-dimensional position, the main control unit 211 determines that the x- and y-direction positions of the optical axis of the optical system match the x- and y-direction positions of the three-dimensional position, and that the z-direction distance is The moving mechanism 150 is controlled so as to achieve a predetermined working distance.

<Position deviation processor 232C>
The positional displacement processing unit 232C performs evaluation processing of positional displacements of the plurality of acquired spectral fundus images. Specifically, the positional displacement processing unit 232C obtains positional displacement information of the plurality of acquired spectral fundus images. The positional deviation information includes the displacement with respect to the reference position and the direction of the displacement. The positional displacement processing unit 232C determines whether the positional displacement of (a part of or the whole of) the spectral fundus image is large based on the obtained positional displacement information. When it is determined that the positional deviation is large, the control unit 210 causes re-acquisition of part or all of the plurality of spectral fundus images.

As shown in FIG. 5, the positional deviation processing section 232C includes a positional deviation information generating section 2321C and a positional deviation determining section 2322C.

<Positional deviation information generator 2321C>
The positional deviation information generator 2321C obtains positional deviation information of the spectral fundus image with respect to the reference image. The reference image may be any of a plurality of spectral fundus images, or the en-face image described above. When any one of the plurality of spectral fundus images is adopted as the reference image, examples of the reference image include a spectral fundus image whose wavelength range is adjacent to the spectral fundus image for which position shift information is to be calculated, and a plurality of spectral fundus images. Spectroscopic fundus image of the shortest wavelength range, Spectroscopic fundus image of the longest wavelength range among the multiple spectral fundus images, Spectrum of the wavelength range near the middle of the analysis wavelength range among the multiple spectral fundus images There is a fundus image, a spectral fundus image in which a predetermined characteristic part of a plurality of spectral fundus images is most clearly rendered (high contrast), and the like.

When the reference image is a spectral fundus image whose wavelength range is adjacent to the spectral fundus image for which positional deviation information is to be calculated, the positional deviation information generation unit 2321C generates the first spectral fundus image among the plurality of acquired spectral fundus images. Position shift information between the first spectral fundus image and the second spectral fundus image is obtained by analyzing the image and the second spectral fundus image. For example, the position shift information generation unit 2321C generates a position corresponding to the characteristic region (blood vessel, diseased region, optic papilla, macula, etc.) identified by the characteristic region identification unit 232A in the first spectral fundus image and the second spectral fundus image. positional deviation information is generated based on the specified displacement. The positional deviation information generation unit 2321C can generate positional deviation information for all of the plurality of spectral fundus images.

<Positional deviation determination unit 2322C>
Based on the positional deviation information obtained by the positional deviation information generating part 2321C, the positional deviation determination unit 2322C determines whether or not the positional deviation of at least one of the spectral fundus images is large.

For example, the positional deviation determination unit 2322C determines whether or not the positional deviation of each spectral fundus image is large. In this case, the positional deviation determination unit 2322C determines that the positional deviation of the spectral fundus image is large when the difference is larger than a predetermined threshold. In some embodiments, the threshold is determined according to the wavelength range. For example, the shorter the wavelength range, the smaller (or larger) the threshold, and the longer the wavelength range, the larger (or smaller) the threshold. For example, if the wavelength range that renders the desired characteristic site most clearly is known, the threshold determined according to that wavelength range may be set to be the smallest.

For example, when it is determined that the positional deviation is large in all of the plurality of spectral fundus images, the positional deviation determination unit 2322C determines whether or not the positional deviation is large for each spectral fundus image. It is determined that the positional deviation of the spectral fundus images (image group) of is large. On the other hand, when it is determined that the positional deviation is not large in any of the plurality of spectral fundus images, the positional deviation determination unit 2322C determines that the positional deviation of the plurality of spectral fundus images (image group) is not large.

For example, when a determination result is obtained as to whether or not the positional deviation is large for each spectral fundus image, the positional deviation determination unit 2322C compares the minimum value (or maximum value) of a plurality of positional deviations with a threshold. When the minimum positional deviation (or maximum positional deviation) is equal to or greater than the threshold, the positional deviation determination unit 2322C determines that the positional deviation of the plurality of spectral fundus images (image group) is large. On the other hand, when the minimum positional deviation (or maximum positional deviation) is less than the threshold, the positional deviation determination unit 2322C determines that the positional deviation of the plurality of spectral fundus images (image group) is not large.

For example, when a determination result is obtained as to whether or not the positional deviation is large for each spectral fundus image, the positional deviation determination unit 2322C applies a predetermined statistical operation to the positional deviations obtained for a plurality of spectral fundus images. to calculate statistics. The type of statistical value may be arbitrary, and may be, for example, average value, minimum value, maximum value, mode value, median value, and the like. Note that the case where the statistical value is the minimum value or the maximum value corresponds to the above example. The positional deviation determination unit 2322C compares the calculated statistical value with a predetermined threshold. When the statistical value is equal to or greater than the threshold, the positional deviation determination unit 2322C determines that the positional deviation of the plurality of spectral fundus images (image group) is large. On the other hand, when the statistical value is less than the threshold, the positional deviation determination unit 2322C determines that the positional deviation of the plurality of spectral fundus images (image group) is not large.

For example, when a determination result is obtained as to whether or not the positional deviation is large for each spectral fundus image, the positional deviation determination unit 2322C determines whether each of the one or more positional deviations obtained for the representative image of the plurality of spectral fundus images is is compared with a predetermined threshold. Examples of representative images include a spectral fundus image in the wavelength range with the shortest wavelength among the plurality of spectral fundus images, a spectral fundus image in the wavelength range with the longest wavelength among the plurality of spectral fundus images, and an analysis of the plurality of spectral fundus images. There are a spectral fundus image in a wavelength range near the middle of the wavelength range, a spectral fundus image in which a predetermined characteristic region is most clearly rendered (high contrast) among a plurality of spectral fundus images, and the like. When all of the one or more positional deviations are equal to or greater than the threshold, the positional deviation determination unit 2322C determines that the positional deviations of the plurality of spectral fundus images (image group) are large. On the other hand, if any of the one or more positional deviations is less than the threshold, the positional deviation determination unit 2322C determines that the positional deviations of the plurality of spectral fundus images (image group) are not large.

In some embodiments, the positional displacement information generating unit 2321C generates positional displacement information for some spectral fundus images selected from a plurality of spectral fundus images. In this case, the positional deviation determination unit 2322C performs the above determination process on the generated positional deviation information. That is, positional displacement is evaluated using a plurality of spectral fundus images for which positional displacement information is generated.

The positional deviation determination process according to the embodiment is not limited to the above example. Further, the processing executed by the positional deviation processing section 232C is not limited to processing based on the positional deviation information generated by the positional deviation information generating section 2321C.

The control unit 210 (main control unit 211) causes re-acquisition of part or all of the plurality of spectral fundus images based on the determination result obtained by the positional deviation determination unit 2322C. For example, the control unit 210 reacquires all of the spectral fundus images when it is determined that the positional deviation of the spectral fundus images is large.

Further, when a determination result is obtained as to whether or not the positional deviation is large for each spectral fundus image, for example, the control unit 210 can reacquire only the spectral fundus image determined to have a large positional deviation. . For example, the control unit 210 reacquires a plurality of spectral fundus images (including adjacent spectral fundus images) corresponding to a second wavelength range including the first wavelength range of the spectral fundus image determined to have a large positional shift. be able to.

In some embodiments, when the number of spectral fundus images determined to have a large positional shift is equal to or greater than a predetermined threshold, the control unit 210 reacquires some or all of the plurality of spectral fundus images.

<Image quality processing unit 232D>
The image quality processing unit 232D performs image quality evaluation processing of the plurality of acquired spectral fundus images. Specifically, the image quality processing unit 232D calculates evaluation values of the image quality of the plurality of acquired spectral fundus images. The image quality processing unit 232D determines quality of image quality (whether the image quality is high or not) based on the calculated evaluation value. When it is determined that the image quality is not good, the control unit 210 causes reacquisition of part or all of the plurality of spectral fundus images.

As shown in FIG. 6, the image quality processing section 232D includes an image quality evaluation value calculation section 2321D and an image quality determination section 2322D.

<Image quality evaluation value calculation unit 2321D>
The image quality evaluation value calculation unit 2321D calculates the evaluation value of the image quality of the spectral fundus image. In some embodiments, the image quality evaluation value calculator 2321D calculates an evaluation value that quantitatively represents the image quality of a plurality of spectral fundus images.

The image quality evaluation value calculation processing by the image quality evaluation value calculation unit 2321D may be arbitrary processing. Examples of image quality evaluation value calculation processing include signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), root-mean-square (RMS) granularity, Wiener spectrum, modulation transfer function (MTF), and quality index. (Quality Index; QI) and other processing using any known technique.

The evaluation value may be any parameter that quantitatively expresses the quality of the image, and typically the higher the quality of the image, the higher the evaluation value.

For example, the image quality evaluation value calculation unit 2321D calculates an image quality value (IQ value) as an evaluation value for the spectral fundus image. In this case, the image quality evaluation value calculation unit 2321D applies predetermined analysis processing to the evaluation region set in the image to be evaluated, thereby obtaining an image region (tissue image region) corresponding to a predetermined tissue (site). and other image areas (background area, non-tissue image area). Next, the image quality evaluation value calculator 2321D generates a luminance histogram in the tissue image region and a luminance histogram in the background region. Subsequently, the image quality evaluation value calculation unit 2321D calculates an image quality evaluation value (IQ value) from the degree of overlap of these two histograms. For example, the IQ value is 0 when both histograms are completely overlapped, and the IQ value is 100 when both histograms are completely separated. IQ values are defined in ranges. This image quality evaluation calculation may include, for example, normalization of two histograms, generation of a probability distribution function, calculation of an IQ value using a predetermined calculation formula, and the like.

In this way, the image quality evaluation value calculation unit 2321D performs the process of identifying the tissue image region corresponding to the predetermined tissue and the background region in the image to be evaluated, and the first histogram showing the frequency distribution of the luminance in the tissue image region. , a process of creating a second histogram indicating the frequency distribution of luminance in the background area, and an image quality evaluation value (IQ value) as image quality evaluation data based on the first histogram and the second histogram. configured to perform a process;

The image quality evaluation value calculation process according to the embodiment is not limited to the above example.

<Image quality determination unit 2322D>
The image quality determination unit 2322D determines quality of at least one of the plurality of spectral fundus images based on the evaluation value calculated by the image quality evaluation value calculation unit 2321D. In some embodiments, the image quality determination unit 2322D determines the quality of a group of images, based on the calculated evaluation value, with a plurality of spectral fundus images as an image group.

For example, when an IQ value is obtained for each spectral fundus image, the image quality determination unit 2322D compares each of the plurality of IQ values obtained for the plurality of spectral fundus images with a predetermined threshold. When all of the multiple IQ values are equal to or greater than the threshold, the image quality determination unit 2322D determines that the quality of the multiple spectral fundus images (image group) is good. On the other hand, if any of the multiple IQ values is less than the threshold, the image quality determination unit 2322D determines that the quality of the multiple spectral fundus images (image group) is not good.

For example, when an IQ value is obtained for each spectral fundus image, the image quality determination unit 2322D selects the lowest IQ value among the plurality of IQ values obtained for the plurality of spectral fundus images, and determines the lowest IQ value. Compare with a predetermined threshold. When the minimum IQ value is equal to or greater than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is good. On the other hand, when the lowest IQ value is less than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is not good.

For example, when an IQ value is obtained for each spectral fundus image, the image quality determination unit 2322D calculates a statistical value by applying a predetermined statistical operation to the plurality of IQ values obtained for the plurality of spectral fundus images. The type of statistical value may be arbitrary, and may be, for example, average value, minimum value, maximum value, mode value, median value, and the like. Note that the case where the statistical value is the minimum value corresponds to the above example. The image quality determination unit 2322D compares the calculated statistical value with a predetermined threshold. When the statistical value is equal to or greater than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is good. On the other hand, if the statistical value is less than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is not good.

For example, when an IQ value is obtained for each spectral fundus image, the image quality determination unit 2322D compares each of one or more IQ values obtained for a representative image of a plurality of spectral fundus images with a predetermined threshold. Examples of representative images include a spectral fundus image in the wavelength range with the shortest wavelength among the plurality of spectral fundus images, a spectral fundus image in the wavelength range with the longest wavelength among the plurality of spectral fundus images, and an analysis of the plurality of spectral fundus images. There are a spectral fundus image in a wavelength range near the middle of the wavelength range, a spectral fundus image in which a predetermined characteristic region is most clearly rendered (high contrast) among a plurality of spectral fundus images, and the like. When all of the IQ values of 1 or more are equal to or greater than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is good. On the other hand, if any of the IQ values of 1 or more is less than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is not good.

For example, when an IQ value is obtained for each spectral fundus image, the image quality determination unit 2322D applies a predetermined statistical operation to two or more IQ values obtained for a representative image of a plurality of spectral fundus images to obtain a statistical value. Calculate The type of statistical value may be arbitrary, and may be, for example, average value, minimum value, maximum value, mode value, median value, and the like. The image quality determination unit 2322D compares the calculated statistical value with a predetermined threshold. When the statistical value is equal to or greater than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is good. On the other hand, if the statistical value is less than the threshold, the image quality determination unit 2322D determines that the quality of the plurality of spectral fundus images (image group) is not good.

In some embodiments, the image quality evaluation value calculation unit 2321D calculates evaluation values for some spectral fundus images selected from a plurality of spectral fundus images. In this case, the image quality determination section 2322D performs the above determination processing on the calculated evaluation value. That is, image quality is evaluated using a plurality of spectral fundus images for which evaluation values have been calculated.

The image quality determination process according to the embodiment is not limited to the above example. Further, the processing executed by the image quality processing section 232D is not limited to processing based on the evaluation value calculated by the image quality evaluation value calculation section 2321D.

The control unit 210 (main control unit 211) causes re-acquisition of part or all of the plurality of spectral fundus images based on the determination result obtained by the image quality determination unit 2322D. For example, the control unit 210 reacquires all of the spectral fundus images when it is determined that the quality of the spectral fundus images is not good.

Further, when the IQ value is obtained for each spectral fundus image, for example, the control unit 210 selects a spectral fundus image whose IQ value is less than a threshold value (a spectral fundus image determined to have poor image quality based on the IQ value). ) can be reacquired. For example, the control unit 210 reacquires a plurality of spectral fundus images (including adjacent spectral fundus images) corresponding to a second wavelength range including a first wavelength range of the spectral fundus images whose IQ values are less than the threshold. can be done.

In some embodiments, when the number of spectral fundus images whose IQ values are less than a threshold is equal to or greater than a predetermined threshold, the control unit 210 reacquire some or all of the plurality of spectral fundus images.

<User Interface 240>
User interface 240 includes a display section 240A and an operation section 240B. Display unit 240A includes display device 3 . The operation unit 240B includes various operation devices and input devices.

The user interface 240 may include a device, such as a touch panel, that combines a display function and an operation function. In other embodiments, at least a portion of the user interface may not be included on the ophthalmic device. For example, the display device may be an external device connected to the ophthalmic equipment.

<Communication unit 250>
The communication unit 250 has a function for communicating with an external device (not shown). The communication unit 250 has a communication interface according to a connection form with an external device. Examples of external devices include server devices, OCT devices, scanning laser ophthalmoscopes, slit lamp ophthalmoscopes, ophthalmic measurement devices, and ophthalmic treatment devices. Examples of ophthalmic measurement devices include eye refractometers, tonometers, specular microscopes, wavefront analyzers, perimeters, microperimeters, and the like. Examples of ophthalmic treatment devices include laser treatment devices, surgical devices, surgical microscopes, and the like. The external device may be a device (reader) that reads information from a recording medium, or a device (writer) that writes information to a recording medium. Furthermore, the external device may be a hospital information system (HIS) server, a DICOM (Digital Imaging and Communication in Medicine) server, a doctor terminal, a mobile terminal, a personal terminal, a cloud server, or the like.

The arithmetic control unit 200 (the control section 210, the image forming section 220, and the data processing section 230) is an example of the "ophthalmic information processing apparatus" according to the embodiment. A plurality of spectroscopic fundus images (spectral images) is an example of "a plurality of images of an eye to be examined obtained by sequentially receiving return light from the eye to be examined in different wavelength ranges" according to the embodiment. A configuration that acquires a plurality of spectral images of an eye to be inspected using a communication function (not shown) or the retinal camera unit 2 (illumination optical system 10, imaging optical system 30) is an example of the "acquisition unit" according to the embodiment. The alignment processing unit 231 is an example of the "alignment unit" according to the embodiment. An en-face image or a C-scan image is an example of an "OCT frontal image" according to embodiments. The positional deviation determination section 2322C is an example of the "first determination section" according to the embodiment. The image quality evaluation value calculation unit 2321D is an example of the "quality evaluation unit" according to the embodiment. The image quality determination unit 2322D is an example of the "second determination unit" according to the embodiment. The imaging optical system 30 is an example of a "light receiving optical system" according to the embodiment. The optical system from the OCT unit 100 to the objective lens 22 is an example of the "OCT optical system" according to the embodiment.

<motion>
An operation example of the ophthalmologic apparatus 1 will be described.

7 to 9 show an operation example of the ophthalmologic apparatus 1 according to the embodiment. FIG. 7 represents a flow diagram of an operation example of the ophthalmologic apparatus 1 . FIG. 8 shows a flow diagram of an example of the operation of step S8 in FIG. FIG. 9 shows a flowchart of another operation example of step S8 in FIG.

The storage unit 212 stores computer programs for realizing the processes shown in FIGS. The main control unit 211 executes the processes shown in FIGS. 7 to 9 by operating according to this computer program.

(S1: Alignment)
First, the main controller 211 executes alignment.

For example, the main control unit 211 controls the anterior eye cameras 5A and 5B to photograph the anterior eye Ea of the subject's eye E substantially simultaneously. The characteristic site identification unit 232A receives control from the main control unit 211, analyzes the pair of anterior segment images obtained substantially simultaneously by the anterior segment cameras 5A and 5B, and identifies the pupil of the subject's eye E as a characteristic site. Identify the center position. The three-dimensional position calculator 232B obtains the three-dimensional position of the eye E to be examined. This processing includes arithmetic processing using trigonometry based on the positional relationship between the pair of anterior eye cameras 5A and 5B and the subject's eye E, as described in Japanese Patent Application Laid-Open No. 2013-248376, for example.

The main control unit 211 moves based on the three-dimensional position of the subject's eye E obtained by the three-dimensional position calculator 232B so that the optical system (for example, the fundus camera unit 2) and the subject's eye E have a predetermined positional relationship. Control mechanism 150 . Here, the predetermined positional relationship is a positional relationship that enables imaging and examination of the subject's eye E using an optical system. As a typical example, when the three-dimensional position (x-coordinate, y-coordinate, z-coordinate) of the eye E to be examined is obtained by the three-dimensional position calculator 232B, the x-coordinate and y-coordinate of the optical axis of the objective lens 22 are the eye E and the difference between the z-coordinate of the objective lens 22 (front lens surface) and the z-coordinate of the eye to be examined E (corneal surface) is equal to a predetermined distance (working distance) , is set as the destination of the optical system.

(S2: Autofocus)
Subsequently, the main controller 211 starts autofocus.

For example, the main controller 211 controls the focus optical system 60 to project the split index on the eye E to be examined. Under the control of the main control unit 211, the analysis unit 232 extracts a pair of split index images by analyzing the observed image of the fundus oculi Ef on which the split indices are projected, and calculates the relative relationship between the pair of split indices. Calculate the deviation. The main control unit 211 controls the focus driving unit 31A and the focus driving unit 43A based on the calculated deviation (direction of deviation, amount of deviation).

(S3: OCT measurement)
Next, the main controller 211 executes OCT measurement.

For example, the main control unit 211 controls the LCD 39 to present the eye E to be examined with the fixation target. Subsequently, the main controller 211 controls the optical scanner 42 and the OCT unit 100 so that OCT measurement is started. Once the OCT measurement is started, the OCT unit 100 sends the data collected in each scan to the imager 220 . The image forming section 220 forms a plurality of B-scan images from the data collected in each scan and sends them to the control section 210 . Control unit 210 sends a plurality of B-scan images corresponding to each scan to data processing unit 230 . For example, data processor 230 forms a three-dimensional image from a plurality of B-scan images corresponding to each scan.

(S4: Set wavelength range)
Next, the main controller 211 controls the wavelength tunable filter 80 to set the wavelength selection range of transmitted light to a predetermined wavelength range. An example of a predetermined wavelength range is an initial wavelength range when sequentially repeating the selection of wavelength ranges to cover the analysis wavelength range.

(S5: Acquire image data)
Next, the main control unit 211 causes the image data of the spectral fundus image to be acquired.

For example, the main control unit 211 controls the illumination optical system 10 to illuminate the subject's eye E with illumination light, captures the light reception result of the reflected light of the illumination light obtained by the image sensor 38, and obtains the image data of the spectral fundus image. get

(S6: next?)
Subsequently, the main control unit 211 determines whether or not to acquire a spectral fundus image in the next wavelength range. For example, when wavelength selection is sequentially changed in predetermined wavelength range steps within the analysis wavelength range, the main control unit 211 determines whether or not to acquire the next spectral fundus image based on the number of times the wavelength range has been changed. can judge. For example, the main control unit 211 can determine whether or not to acquire the next spectral fundus image by determining whether or not all of a plurality of predetermined wavelength ranges have been selected.

When it is determined in step S6 that the next spectral fundus image is to be obtained (step S6: Y), the operation of the ophthalmologic apparatus 1 proceeds to step S7. In step S6, when it is determined not to acquire the next spectral fundus image (step S6: N), the operation of the ophthalmologic apparatus 1 proceeds to step S8.

(S7: Change wavelength range)
When it is determined in step S6 that the next spectral fundus image is to be acquired (step S6: Y), the main control unit 211 controls the wavelength tunable filter 80 to select the range of transmitted light to be selected next. change. Subsequently, the operation of the ophthalmologic apparatus 1 proceeds to step S5.

(S8: re-shooting process)
When it is determined in step S6 that the next spectral fundus image will not be acquired (step S6: N), the main control unit 211 executes re-capturing processing, and if necessary, re-acquires the spectral fundus image. conduct. Details of step S8 will be described later.

Following step S8, the operation of the ophthalmologic apparatus 1 ends (end).

For example, in step S8, a process of determining whether or not to reacquire the spectral fundus images by evaluating the positional deviation of the plurality of spectral fundus images (FIG. 8), or evaluating the image quality of the plurality of spectral fundus images. By doing so, the process (FIG. 9) of determining whether or not to reacquire the spectral fundus image is executed.

First, as shown in FIG. 8, the case of evaluating the positional deviation of a plurality of spectral fundus images will be described.

(S11: alignment)
When a plurality of spectral fundus images within a predetermined analysis wavelength range are acquired according to the flow shown in FIG. Alignment processing of a plurality of spectral fundus images is executed based on the above.

The OCT data may be the result of interference light detection acquired in step S3, a B-scan image, or an en-face image.

(S12: Generate misalignment information)
Subsequently, the main control unit 211 controls the positional displacement information generating unit 2321C to generate the positional displacement information of the plurality of spectral fundus images for which the alignment processing has been performed in step S11.

(S13: Reacquisition?)
Next, the main control unit 211 controls the positional displacement determination unit 2322C to determine whether or not the positional displacement of the plurality of spectral fundus images is large based on the positional displacement information generated in step S12. The main control unit 211 reacquires part or all of the plurality of spectral fundus images when the positional displacement determination unit 2322C determines that the positional displacement of the plurality of spectral fundus images is large. The reacquired spectral fundus image may be the spectral fundus image determined to have a large positional shift, or two or more spectral fundus images including the spectral fundus image determined to have a large positional shift.

When it is determined in step S13 that the positional deviation is large (step S13: Y), the process of step S8 proceeds to step S14. When it is determined in step S13 that the positional deviation is not large (step S13: N), the process of step S8 ends (end).

(S14: Set wavelength range)
When it is determined in step S13 that the positional deviation is large (step S13: Y), the main control unit 211 controls the wavelength tunable filter 80 so that the wavelength selection range of the transmitted light corresponds to the spectral fundus image to be reacquired. set to the specified wavelength range.

(S15: Acquire image data)
Next, the main control unit 211 acquires the image data of the spectral fundus image as in step S5.

(S16: next?)
Subsequently, the main control unit 211 determines whether or not to reacquire the spectral fundus image in the next wavelength range.

When it is determined in step S16 that the next spectral fundus image is to be reacquired (step S16: Y), the process of step S8 proceeds to step S17. When it is determined in step S16 that the next spectroscopic fundus image is not to be reacquired (step S16: N), the process of step S8 ends (end).

(S17: Change wavelength range)
When it is determined in step S16 that the next spectral fundus image is to be reacquired (step S16: Y), the main control unit 211 controls the wavelength tunable filter 80 to select the range of transmitted light to be selected next. to change Subsequently, the process of step S8 proceeds to step S15.

Next, as shown in FIG. 9, a case of evaluating image quality deviations of a plurality of spectral fundus images will be described.

(S21: alignment)
When a plurality of spectral fundus images within a predetermined analysis wavelength range are acquired according to the flow shown in FIG. Alignment processing of a plurality of spectral fundus images is executed based on the acquired OCT data.

(S22: Calculate image quality evaluation value)
Subsequently, the main control unit 211 controls the image quality evaluation value calculation unit 2321D to calculate the image quality evaluation values of the plurality of spectral fundus images subjected to the alignment processing in step S11.

(S23: Reacquisition?)
Next, the main control unit 211 controls the image quality determination unit 2322D to determine whether the image quality of the plurality of spectral fundus images is good or bad based on the evaluation value calculated in step S22. When the image quality determination unit 2322D determines that the image quality of the plurality of spectral fundus images is not good, the main control unit 211 reacquires some or all of the plurality of spectral fundus images. The reacquired spectral fundus image may be the spectral fundus image determined to have poor image quality, or two or more spectral fundus images including the spectral fundus image determined to have poor image quality.

When it is determined in step S23 that the image quality is not good (step S23: Y), the processing in step S8 proceeds to step S24. When it is determined in step S23 that the image quality is not good (step S23: N), the process of step S8 is terminated (END).

(S24: Set wavelength range)
When it is determined in step S23 that the image quality is not good (step S23: Y), the main control unit 211 controls the wavelength tunable filter 80 to change the wavelength selection range of the transmitted light to the spectral fundus image to be reacquired. Set to the corresponding wavelength range.

(S25: Acquire image data)
Next, the main control unit 211 acquires the image data of the spectral fundus image as in step S15.

(S26: next?)
Subsequently, the main control unit 211 determines whether or not to reacquire the spectral fundus image in the next wavelength range.

When it is determined in step S26 that the next spectral fundus image is to be reacquired (step S26: Y), the process of step S8 proceeds to step S27. When it is determined in step S26 that the next spectroscopic fundus image will not be reacquired (step S26: N), the process of step S8 ends (end).

(S27: Change wavelength range)
When it is determined in step S26 that the next spectral fundus image is to be reacquired (step S26: Y), the main control unit 211 controls the wavelength tunable filter 80 to select the range of transmitted light to be selected next. to change Subsequently, the process of step S8 proceeds to step S25.

<Action>
An ophthalmologic information processing apparatus, an ophthalmologic apparatus, an ophthalmologic information processing method, and a program according to embodiments will be described.

The ophthalmologic information processing apparatus (the control unit 210, the image forming unit 220, and the data processing unit 230) according to some embodiments includes an acquisition unit (a configuration for acquiring a plurality of spectral images of the subject's eye using a communication function (not shown), or It includes a retinal camera unit 2 (illumination optical system 10, imaging optical system 30) and an alignment section (alignment processing section 231). The acquisition unit obtains a plurality of images of the eye (spectral image, spectral fundus image, spectral anterior eye image). The alignment unit aligns a plurality of images based on OCT data obtained by performing optical coherence tomography on the subject's eye.

According to such a configuration, spectral characteristics can be easily compared between images even when fixation dislocation and alignment misalignment between the subject's eye and the imaging unit occur while acquiring a plurality of images. become. In particular, by performing alignment based on OCT data, it becomes possible to perform highly accurate alignment between images based on information in the depth direction (depth direction) of the eye, and the spectroscopy at the observation site of the subject's eye becomes possible. It becomes possible to improve the accuracy of the analysis.

In some embodiments, the OCT data is the result of interference light detection, a B-scan image, an OCTA (OCT Angiography) image, or an en-face image obtained by performing optical coherence tomography on the eye to be examined. is.

According to such a configuration, it is possible to easily and highly accurately align a plurality of images using OCT data that can be acquired with an existing optical system.

In some embodiments, the alignment unit aligns the image of the subject's eye with the OCT enface image at a depth position corresponding to the wavelength range of this image.

According to such a configuration, since the images are aligned based on the OCT front image at the depth position corresponding to the wavelength range of the alignment target image, highly accurate alignment is possible. .

Some embodiments include a displacement information generator (2321C) that obtains displacement information between the first image and the second image by analyzing the first image and the second image among the plurality of images. including.

According to such a configuration, when a fixation shift and misalignment between the subject's eye and the imaging unit occur while a plurality of images are being acquired, positional shift between the plurality of images can be obtained by obtaining the positional shift between the images. It becomes possible to quantitatively evaluate the quality of a plurality of captured images.

Some embodiments include a first determination unit (displacement determination unit 2322C) that determines whether the misalignment between the first image and the second image is large based on misalignment information. The acquisition unit reacquires the first image or the second image based on the determination result obtained by the determination unit.

According to such a configuration, it is possible to acquire a plurality of images with small positional deviations, and it is possible to improve the accuracy of spectroscopic analysis of the observation site of the subject's eye.

Some embodiments include a quality evaluation unit (image quality evaluation value calculation unit 2321D) that calculates a quality evaluation value for at least one of a plurality of images.

According to such a configuration, an evaluation value of at least one quality of a plurality of images is calculated when fixation dislocation and alignment misalignment between the subject's eye and the imaging unit occur while acquiring a plurality of images. By doing so, it becomes possible to quantitatively evaluate the quality of a plurality of acquired images.

Some embodiments include a second determination unit (image quality determination unit 2322D) that determines the quality of the plurality of images based on the evaluation value, and based on the determination result obtained by the second determination unit, the acquisition The unit reacquires at least one or all of the images of the plurality of images.

According to such a configuration, it is possible to acquire a plurality of images with good image quality, and it is possible to improve the accuracy of spectroscopic analysis of the observation site of the subject's eye.

An ophthalmologic apparatus (1) according to some embodiments includes an illumination optical system (10), a light receiving optical system (imaging optical system 30), an OCT optical system (an optical system from an OCT unit 100 to an objective lens 22), and , and any one of the ophthalmological information processing devices described above. The illumination optical system illuminates the subject's eye with illumination light. The light-receiving optical system sequentially receives return light of illumination light from the subject's eye having different wavelength ranges. The OCT optical system performs optical coherence tomography on the subject's eye. The acquisition unit sequentially acquires a plurality of images based on the light reception result obtained by the light reception optical system.

According to such a configuration, even when a fixation shift or misalignment between the subject's eye and the imaging unit occurs while a plurality of images are being acquired, the image can be detected based on information in the depth direction (depth direction) of the eye. Therefore, it is possible to provide an ophthalmologic apparatus capable of improving the accuracy of spectroscopic analysis of the observation site of the subject's eye.

An ophthalmic information processing method according to some embodiments includes an acquisition step and an alignment step. The alignment step acquires a plurality of images of the eye to be inspected obtained by sequentially receiving return lights having different wavelength ranges from the eye to be inspected illuminated by the illumination light. The alignment step aligns a plurality of images based on OCT data obtained by performing optical coherence tomography on the subject's eye.

According to such a method, spectral characteristics can be easily compared between images even when fixation dislocation and alignment misalignment between the subject's eye and the imaging unit occur while acquiring a plurality of images. become. In particular, by performing alignment based on OCT data, it becomes possible to perform highly accurate alignment between images based on information in the depth direction (depth direction) of the eye, and the spectroscopy at the observation site of the subject's eye becomes possible. It becomes possible to improve the accuracy of the analysis.

In some embodiments, the OCT data is the result of interference light detection, a B-scan image, an OCTA (OCT Angiography) image, or an en-face image obtained by performing optical coherence tomography on the eye to be examined. is.

According to such a method, it is possible to easily align a plurality of images with high accuracy using OCT data that can be acquired with an existing optical system.

In some embodiments, the aligning step aligns the image of the subject's eye with the OCT frontal image at a depth position corresponding to the wavelength range of the image.

According to this method, since the images are aligned based on the OCT front image at the depth position corresponding to the wavelength range of the image to be aligned, highly accurate alignment is possible. .

Some embodiments include generating misregistration information for obtaining misregistration information between the first and second images by analyzing the first and second images of the plurality of images.

According to such a method, when a fixation shift and misalignment between the subject's eye and the imaging unit occur while a plurality of images are being acquired, positional shifts between the plurality of images are obtained to obtain the images. It becomes possible to quantitatively evaluate the quality of a plurality of captured images.

Some embodiments include a first determining step of determining whether the displacement between the first image and the second image is large based on the misalignment information, and the determination obtained in the first determining step Based on the results, the acquiring step reacquires the first image or the second image.

According to such a method, it is possible to acquire a plurality of images with small positional deviations, and it is possible to improve the accuracy of spectroscopic analysis of the observation site of the subject's eye.

Some embodiments include a quality assessment step of calculating a quality assessment value for at least one of the plurality of images.

According to this method, an evaluation value of at least one quality of a plurality of images is calculated when fixation dislocation and alignment misalignment between the subject's eye and the imaging unit occur while acquiring a plurality of images. By doing so, it becomes possible to quantitatively evaluate the quality of a plurality of acquired images.

Some embodiments include a second determination step of determining whether the quality of the plurality of images is good or bad based on the evaluation value, and based on the determination result obtained in the second determination step, the obtaining step determines the quality of the plurality of images reacquire all of at least one or more images of .

According to such a method, it is possible to acquire a plurality of images with good image quality, and it is possible to improve the accuracy of spectroscopic analysis of the observation site of the subject's eye.

A program according to some embodiments causes a computer to execute each step of any one of the ophthalmologic information processing methods described above.

According to such a program, even if a fixation shift or misalignment between the subject's eye and the imaging unit occurs while acquiring a plurality of images, the image can be detected based on the information in the depth direction (depth direction) of the eye. It becomes possible to align the images with high accuracy by using a computer program, and it is possible to provide a computer program capable of improving the accuracy of spectroscopic analysis of the observation site of the subject's eye.

The embodiment described above is merely an example of the present invention. A person who intends to implement this invention can arbitrarily make modifications (omissions, substitutions, additions, etc.) within the scope of the gist of this invention.

In some embodiments, the storage unit 212 stores a program that causes a computer to execute a method of controlling an ophthalmologic apparatus. Such a program may be stored in any computer-readable recording medium. The recording medium may be electronic media using magnetism, light, magneto-optics, semiconductors, and the like. Typically, recording media are magnetic tapes, magnetic disks, optical disks, magneto-optical disks, flash memories, solid state drives, and the like.

1 ophthalmologic apparatus 2 retinal camera unit 10 illumination optical system 22 objective lens 30 imaging optical system 80 wavelength tunable filter 100 OCT unit 210 control unit 211 main control unit 220 image forming unit 230 data processing unit 231 alignment processing unit 232 analysis unit 232A Features Part identification unit 232B Three-dimensional position calculation unit 232C Position shift processing unit 2321C Position shift information generation unit 2322C Position shift determination unit 232D Image quality processing unit 2321D Image quality evaluation value calculation unit 2322D Image quality determination unit E Eye to be examined Ef Fundus LS Measurement light

Claims (16)

an acquisition unit that acquires a plurality of images of the eye to be inspected obtained by sequentially receiving return lights having different wavelength ranges from the eye to be inspected illuminated by the illumination light;
an alignment unit that aligns the plurality of images based on OCT data obtained by performing optical coherence tomography on the eye to be inspected;
An ophthalmic information processing device, comprising: The OCT data is a detection result of interference light obtained by performing optical coherence tomography on the eye to be examined, a B-scan image, an OCTA (OCT Angiography) image, or an en-face image. The ophthalmologic information processing apparatus according to claim 1. The ophthalmologic information processing apparatus according to claim 1, wherein the alignment unit performs alignment between the image of the subject's eye and an OCT front image at a depth position corresponding to a wavelength range of the image. and a positional deviation information generation unit that acquires positional deviation information between the first image and the second image by analyzing the first image and the second image among the plurality of images. The ophthalmologic information processing apparatus according to any one of claims 1 to 3. a first determination unit that determines whether the displacement between the first image and the second image is large based on the displacement information;
The ophthalmologic information processing apparatus according to claim 4, wherein the acquisition unit reacquires the first image or the second image based on the determination result obtained by the first determination unit. The ophthalmologic information processing apparatus according to any one of claims 1 to 5, further comprising a quality evaluation unit that calculates an evaluation value of quality of at least one of the plurality of images. a second determination unit that determines whether the quality of the plurality of images is good or bad based on the evaluation value;
7. The ophthalmology clinic according to claim 6, wherein the acquisition unit reacquires at least one of the plurality of images or all of the plurality of images based on the determination result obtained by the second determination unit. Information processing equipment. an illumination optical system that illuminates the subject's eye with illumination light;
a light-receiving optical system that sequentially receives return light of the illumination light from the eye to be inspected, the wavelength ranges of which are different from each other;
an OCT optical system that performs optical coherence tomography on the eye to be examined;
an ophthalmologic information processing apparatus according to any one of claims 1 to 7;
including
The ophthalmologic apparatus, wherein the obtaining unit sequentially obtains the plurality of images based on light reception results obtained by the light receiving optical system. an acquisition step of acquiring a plurality of images of the eye to be inspected obtained by sequentially receiving return lights having different wavelength ranges from the eye to be inspected illuminated by the illumination light;
an alignment step of aligning the plurality of images based on OCT data obtained by performing optical coherence tomography on the eye to be inspected;
An ophthalmic information processing method, comprising: The OCT data is a detection result of interference light obtained by performing optical coherence tomography on the eye to be examined, a B-scan image, an OCTA (OCT Angiography) image, or an en-face image. The ophthalmologic information processing method according to claim 9. 10. The ophthalmologic information processing method according to claim 9, wherein the alignment step performs alignment between the image of the subject's eye and an OCT front image at a depth position corresponding to a wavelength range of the image. and a positional deviation information generating step of acquiring positional deviation information between the first image and the second image by analyzing the first image and the second image among the plurality of images. The ophthalmologic information processing method according to any one of claims 9 to 11. A first determination step of determining whether or not the positional deviation between the first image and the second image is large based on the positional deviation information;
13. The ophthalmologic information processing method according to claim 12, wherein said acquisition step re-acquires said first image or said second image based on the determination result obtained in said first determination step. The ophthalmologic information processing method according to any one of claims 9 to 13, further comprising a quality evaluation step of calculating an evaluation value of quality of at least one of said plurality of images. a second determination step of determining whether the quality of the plurality of images is good or bad based on the evaluation value;
15. The method according to claim 14, wherein the acquisition step acquires again at least one of the plurality of images or all of the plurality of images based on the determination result obtained in the second determination step. Ophthalmic information processing method. A program for causing a computer to execute each step of the ophthalmologic information processing method according to any one of claims 9 to 15.

Images