WO2017090550A1

WO2017090550A1 - Ophthalmological device

Info

Publication number: WO2017090550A1
Application number: PCT/JP2016/084403
Authority: WO
Inventors: 釣　滋孝
Original assignee: 株式会社トプコン
Priority date: 2015-11-25
Filing date: 2016-11-21
Publication date: 2017-06-01
Also published as: JP2017093855A; JP6637743B2

Abstract

An ophthalmological device of an embodiment of the present invention is provided with a storage unit, a data accumulation unit, a processing unit, a comparison unit, and an output unit. The storage unit stores in advance a standard graph in which a standard distribution of characteristic values is expressed using a coordinate system that includes a first coordinate axis indicating a position of an eye within a prescribed range, and a second coordinate axis indicating the magnitude of a prescribed characteristic value of the eye. The data accumulating unit uses optical coherence tomography to accumulate data of an eye-under-test region which includes a target site corresponding to the prescribed range. The processing unit processes the accumulated data to create a distribution graph in which the distribution of the characteristic values of the target site is expressed using the coordinate system. The comparison unit compares the distribution graph which was created and the standard graph. The output unit outputs the results of the comparison between the distribution graph and the standard graph.

Description

Ophthalmic equipment

The present invention relates to an ophthalmologic apparatus.

Optical coherence tomography (OCT) has become an indispensable examination in ophthalmic practice. For example, in the diagnosis of fundus diseases such as glaucoma, the thickness distribution of a predetermined tissue (for example, retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, etc.) is obtained from the fundus data obtained by OCT, Is compared with standard data to determine the presence and extent of the disease (see, for example, Patent Document 1). The standard data is statistically derived from a large number of normal eye measurement data, and is called normal eye data (normal data) or the like.

JP2015-80677A

In such a conventional comparative diagnosis, the layer thickness distribution of the eye to be examined and the standard layer thickness distribution obtained by OCT are registered, and the layer thickness value of each point in the layer thickness distribution of the eye to be examined and the standard layer thickness distribution. Is performed by comparing the standard layer thickness value of the corresponding point. Therefore, the accuracy and accuracy of registration greatly affect the comparison result.

Also, the thickness of the organization varies greatly between individuals. For example, there are eyes whose tissues are generally thinner than standard or thick eyes. In the conventional method that compares only the magnitudes of the layer thickness values, such individual differences are not taken into consideration, and therefore there is a possibility that a comparison result with sufficient accuracy cannot be obtained depending on the eye to be examined.

The purpose of the ophthalmic apparatus according to the present invention is to improve the accuracy of comparative diagnosis using standard data.

The ophthalmologic apparatus of the embodiment includes a storage unit, a data collection unit, a processing unit, a comparison unit, and an output unit. The storage unit displays a standard graph in which a standard distribution of characteristic values is expressed by a coordinate system including a first coordinate axis representing a position in a predetermined range of the eye and a second coordinate axis representing a magnitude of the predetermined characteristic value of the eye. Store in advance. The data collection unit collects data of a region of the eye to be examined including a target region corresponding to a predetermined range using optical coherence tomography. The processing unit processes the collected data to create a distribution graph in which the distribution of characteristic values in the target region is expressed by the coordinate system. The comparison unit compares the created distribution graph with the standard graph. The output unit outputs a comparison result between the distribution graph and the standard graph.

According to the embodiment, it is possible to improve the accuracy of comparative diagnosis using standard data.

Schematic showing an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic showing an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic showing an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic showing an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic for demonstrating an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic for demonstrating an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic for demonstrating an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic for demonstrating an example of a structure of the ophthalmologic apparatus which concerns on embodiment. Schematic for demonstrating an example of a structure of the ophthalmologic apparatus which concerns on embodiment. The flowchart showing an example of operation | movement of the ophthalmologic apparatus which concerns on embodiment. Schematic showing an example of a structure of the ophthalmologic apparatus which concerns on a modification.

Several embodiments of the present invention will be described in detail with reference to the drawings. The ophthalmologic apparatus of the embodiment has a function of executing optical coherence tomography (OCT) of the eye to be examined.

Hereinafter, although an ophthalmologic apparatus combining a swept source OCT and a fundus camera will be described, the embodiment is not limited thereto. For example, the type of OCT is not limited to the swept source OCT, and may be a spectral domain OCT or a full field OCT (in-face OCT). In addition, the ophthalmologic apparatus of the embodiment may or may not have a function of acquiring a photograph (digital photograph) of the eye to be examined like a fundus camera. Further, a slit lamp microscope, an anterior ocular segment photographing camera, or a surgical microscope may be provided instead of the fundus camera.

<Constitution>
The ophthalmologic apparatus 1 shown in FIG. 1 is used for taking a photograph of the eye E and OCT. The ophthalmologic apparatus 1 includes a fundus camera unit 2, an OCT unit 100, and an arithmetic control unit 200. The fundus camera unit 2 is provided with optical systems and mechanisms that are substantially the same as those of a conventional fundus camera. The OCT unit 100 is provided with an optical system and a mechanism for performing OCT. The arithmetic control unit 200 includes a processor. A chin rest and a forehead support for supporting the face of the subject are provided at positions facing the fundus camera unit 2.

In this specification, the “processor” is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (eg, SPLD (Simple ProGLD). It means a circuit such as Programmable Logic Device (FPGA) or Field Programmable Gate Array (FPGA). For example, the processor implements the functions according to the embodiment by reading and executing a program stored in a storage circuit or a storage device.

<Fundus camera unit 2>
The fundus camera unit 2 is provided with an optical system and mechanism for acquiring a digital photograph of the eye E to be examined. The digital image of the eye E includes an observation image and a captured image. The observation image is obtained, for example, by moving image shooting using near infrared light. The captured image is, for example, a color image or monochrome image obtained using visible flash light, or a monochrome image obtained using near-infrared flash light. The fundus camera unit 2 may be able to acquire a fluorescein fluorescent image, an indocyanine green fluorescent image, a spontaneous fluorescent image, or the like.

The fundus camera unit 2 includes an illumination optical system 10 and a photographing optical system 30. The illumination optical system 10 projects illumination light onto the eye E to be examined. The imaging optical system 30 detects the return light of the illumination light from the eye E. The measurement light from the OCT unit 100 is guided to the eye E through the optical path in the fundus camera unit 2, and the return light is guided to the OCT unit 100 through the same optical path.

The observation light source 11 of the illumination optical system 10 is, for example, a halogen lamp or an LED (Light Emitting Diode). The light (observation illumination light) output from the observation light source 11 is reflected by the reflection mirror 12 having a curved reflection surface, passes through the condensing lens 13, passes through the visible cut filter 14, and is converted into near infrared light. Become. Further, the observation illumination light is once converged in the vicinity of the photographing light source 15, reflected by the mirror 16, and passes through the

relay lenses

17 and 18, the diaphragm 19 and the relay lens 20. Then, the observation illumination light is reflected by the peripheral part of the perforated mirror 21 (area around the perforated part), passes through the dichroic mirror 46, and is refracted by the objective lens 22 so as to pass through the eye E (especially the fundus oculi Ef). Illuminate.

The return light of the observation illumination light from the 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 perforated mirror 21, and passes through the dichroic mirror 55. The light is reflected by the mirror 32 via the photographing focusing lens 31. Further, the return light passes through the half mirror 33A, is reflected by the dichroic mirror 33, and forms an image on the light receiving surface of the CCD image sensor 35 by the condenser lens. The CCD image sensor 35 detects the return light at a predetermined frame rate, for example. Note that an observation image of the fundus oculi Ef is obtained when the photographing optical system 30 is focused on the fundus oculi Ef, and an anterior eye observation image is obtained when the focus is on the anterior eye segment.

The imaging light source 15 is a visible light source including, for example, a xenon lamp or an LED. The light (imaging illumination light) output from the imaging light source 15 is applied to the fundus oculi Ef through the same path as the observation illumination light. The return light of the imaging illumination light from the 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 is reflected by the condenser lens 37. An image is formed on the light receiving surface of the CCD image sensor 38.

LCD 39 displays a fixation target for fixing the eye E to be examined. A part of the light beam (fixed light beam) output from the LCD 39 is reflected by the half mirror 33A, reflected by the mirror 32, and passes through the photographing focusing lens 31 and the dichroic mirror 55, and then the hole of the aperture mirror 21. Passes through the dichroic mirror 46, is refracted by the objective lens 22, and is 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 eye E can be changed. Instead of the LCD 39, a matrix LED in which a plurality of LEDs are two-dimensionally arranged, or a combination of a light source and a variable diaphragm (liquid crystal diaphragm or the like) can be applied.

The fundus camera unit 2 is provided with an alignment optical system 50 and a focus optical system 60. The alignment optical system 50 generates an alignment index used for alignment of the optical system with respect to the eye E. The focus optical system 60 generates a split index used for focus adjustment with respect to the eye E.

Alignment light output from the LED 51 of the alignment optical system 50 is reflected by the dichroic mirror 55 via the

apertures

52 and 53 and the relay lens 54, and passes through the hole of the perforated mirror 21. The light that has passed through the hole of the perforated mirror 21 passes through the dichroic mirror 46 and is projected onto the eye E by the objective lens 22.

The cornea-reflected light of the alignment light passes through the objective lens 22, the dichroic mirror 46, and the hole, part of which passes through the dichroic mirror 55, passes through the photographing focusing lens 31, is reflected by the mirror 32, and is half The light passes through the mirror 33A, is reflected by the dichroic mirror 33, and is projected onto the light receiving surface of the CCD image sensor 35 by the condenser lens. Based on the received light image (alignment index image) by the CCD image sensor 35, manual alignment and auto alignment similar to the conventional one can be performed.

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 (imaging optical path) of the imaging optical system 30. The reflection bar 67 can be inserted into and removed from the illumination optical path.

When performing focus adjustment, the reflecting surface of the reflecting rod 67 is obliquely provided in the illumination light path. The focus light output from the LED 61 passes through the relay lens 62, is separated into two light beams by the split target plate 63, passes through the two-hole aperture 64, is reflected by the mirror 65, and is reflected by the condenser lens 66. An image is once formed on the reflection surface 67 and reflected. Further, the focus 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 detected by the CCD image sensor 35 through the same path as the corneal reflected light of the alignment light. Based on the received image (split index image) by the CCD image sensor 35, manual alignment and auto-alignment similar to the conventional one can be performed.

The photographing optical system 30 includes

diopter correction lenses

70 and 71. The

diopter correction lenses

70 and 71 can be selectively inserted into a photographing optical path between the perforated mirror 21 and the dichroic mirror 55. The diopter correction lens 70 is a plus (+) lens for correcting intensity hyperopia, for example, a + 20D (diopter) convex lens. The diopter correction lens 71 is a minus (−) lens for correcting high myopia, for example, a −20D concave lens. The

diopter correction lenses

70 and 71 are mounted on, for example, a turret plate. The turret plate is formed with a hole for the case where none of the

diopter correction lenses

70 and 71 is applied.

The dichroic mirror 46 combines the optical path for fundus imaging and the optical path for OCT. The dichroic mirror 46 reflects light in a wavelength band used for OCT and transmits light for fundus photographing. In the optical path for OCT, a collimator lens unit 40, an optical path length changing unit 41, an optical scanner 42, an OCT focusing lens 43, a mirror 44, and a relay lens 45 are provided in this order from the OCT unit 100 side.

The optical path length changing unit 41 is movable in the direction of the arrow shown in FIG. 1, and changes the optical path length of the optical path for OCT. This change in the optical path length is used for correcting the optical path length according to the axial length of the eye E or adjusting the interference state. The optical path length changing unit 41 includes, for example, a corner cube and a mechanism for moving the corner cube.

The optical scanner 42 is disposed at a position optically conjugate with the pupil of the eye E to be examined. The optical scanner 42 changes the traveling direction of the measurement light LS that passes through the optical path for OCT. Thereby, the eye E is scanned with the measurement light LS. The optical scanner 42 can deflect the measurement light LS in an arbitrary direction on the xy plane, and includes, for example, a galvanometer mirror that deflects the measurement light LS in the x direction and a galvanometer mirror that deflects the measurement light LS in the y direction.

<OCT unit 100>
As illustrated in FIG. 2, the OCT unit 100 is provided with an optical system for performing OCT of the eye E. The configuration of this optical system is the same as that of the conventional swept source OCT. That is, this optical system divides the light from the wavelength sweep type (wavelength scanning type) light source into the measurement light and the reference light, and returns the return light of the measurement light from the eye E and the reference light via the reference light path. An interference optical system that generates interference light by causing interference and detects the interference light is included. A detection result (detection signal) 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 a wavelength swept type (wavelength scanning type) light source that changes the wavelength of the emitted light at high speed, like a general swept source OCT. The wavelength sweep type light source is, for example, a near infrared laser light source.

The light L0 output from the light source unit 101 is guided to the polarization controller 103 by the optical fiber 102 and its polarization state is adjusted. Further, the light L0 is guided to the fiber coupler 105 by the optical fiber 104 and is divided 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, converted into a parallel light 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 turns the traveling direction of the incident reference light LR in the reverse direction. The incident direction and the emitting direction of the reference light LR with respect to the corner cube 114 are parallel to each other. The corner cube 114 is movable in the incident direction of the reference light LR, and thereby the optical path length of the reference light LR is changed.

1 and 2, the 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 the optical path (reference optical path, reference arm) of the reference light LR are used. Both corner cubes 114 for changing the length are provided, but only one of the optical path length changing unit 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 using optical members other than these.

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

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. Then, the light passes through the relay lens 45, is reflected by the dichroic mirror 46, is 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. The return light of the measurement light LS from the eye E travels in the reverse direction on 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.

The fiber coupler 122 combines (interferences) the measurement light LS incident through the optical fiber 128 and the reference light LR incident through the optical fiber 121 to generate interference light. The fiber coupler 122 generates a pair of interference light LC by branching the interference light at a predetermined branching ratio (for example, 1: 1). The pair of interference lights LC are guided to the detector 125 through

optical fibers

123 and 124, respectively.

The detector 125 is, for example, a balanced photodiode (Balanced Photo Diode). The balanced photodiode has a pair of photodetectors that respectively detect the pair of interference lights LC, and outputs a difference between detection results obtained by these. The detector 125 sends the detection result (detection signal) to a DAQ (Data Acquisition System) 130.

The clock KC is supplied from the light source unit 101 to the DAQ 130. The clock KC is generated in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the wavelength sweep type light source in the light source unit 101. For example, the light source unit 101 optically delays one of the two branched lights obtained by branching the light L0 of each output wavelength, and then generates a 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. The DAQ 130 sends the sampling result of the detection signal from the detector 125 to the arithmetic control unit 200.

<Calculation control unit 200>
The arithmetic control unit 200 controls each part of the fundus camera unit 2, the display device 3, and the OCT unit 100. The arithmetic control unit 200 executes various arithmetic processes. For example, the arithmetic control unit 200 performs signal processing such as Fourier transform on the spectrum distribution based on the detection result obtained by the detector 125 for each series of wavelength scans (for each A line). A reflection intensity profile is formed. Furthermore, the arithmetic control unit 200 forms image data by imaging the reflection intensity profile of each A line. The arithmetic processing for that is the same as the conventional swept source OCT.

The arithmetic control unit 200 includes, for example, a processor, a RAM (Random Access Memory), a ROM (Read Only Memory), a hard disk drive, a communication interface, and the like. Various computer programs are stored in a storage device such as a hard disk drive. The arithmetic control unit 200 may include an operation device, an input device, a display device, and the like.

<Control system>
A configuration example of the control system of the ophthalmologic apparatus 1 is shown in FIG.

<Control unit 210>
The control unit 210 controls each unit of the ophthalmologic apparatus 1. Control unit 210 includes a processor. The control unit 210 is provided with a main control unit 211 and a storage unit 212.

<Main control unit 211>
The main control unit 211 performs various controls. For example, the main control unit 211 includes an imaging focusing lens 31, CCDs (image sensors) 35 and 38, an LCD 39, an optical path length changing unit 41, an optical scanner 42, an OCT focusing lens 43, a focus optical system 60, a reflector 67, The light source unit 101, the reference driving unit 114A, the detector 125, the DAQ 130, and the like are controlled. The reference driving unit 114A moves the corner cube 114 provided in the reference optical path. Thereby, the length of the reference optical path is changed.

The ophthalmologic apparatus 1 may include an optical system moving mechanism (not shown). The optical system moving mechanism moves the fundus camera unit 2 (or at least a part of the optical system stored therein) and the OCT unit 100 (or at least a part of the optical system stored therein) in a three-dimensional manner.

<Storage unit 212>
The storage unit 212 stores various data. Examples of the data stored in the storage unit 212 include image data of an OCT image, image data of a fundus image, and eye information to be examined. The eye information includes subject information such as patient ID and name, left / right eye identification information, electronic medical record information, and the like.

In the storage unit 212, normal eye data 212a is stored in advance. The normal eye data 212a is obtained by collecting measurement data of at least eyes (normal eyes) diagnosed as not suffering from a predetermined injury and disease, and statistically processing them. The normal eye data 212a represents a standard value of normal eye measurement data. The normal eye data 212a includes, for example, a typical standard value such as an average value or an intermediate value, and a value representing a range such as a standard deviation, variance, maximum value, minimum value, or the like regarding a predetermined characteristic value of normal eyes. Alternatively, the normal eye data 212a includes a threshold value of a predetermined characteristic value of the normal eye.

The characteristic value to be measured is a value that is known to change according to the presence or absence and degree of a predetermined injury or illness, and is a value that can be derived from data collected by an OCT scan. For example, the characteristic value may be a size of a fundus tissue referred to in diagnosis of a fundus disease such as glaucoma. Specific examples thereof include the thickness of a layer tissue composed of a retinal nerve fiber layer, a ganglion cell, an inner plexiform layer, or any combination thereof. Further, the choroid thickness, the diameter and inclination of the optic disc, the diameter and number and distribution of the pores of the phloem plate, the cornea thickness distribution and the curvature distribution, etc. are examples of characteristic values. The characteristic values are not limited to these, and any characteristic value can be adopted according to the purpose for which the ophthalmologic apparatus 1 is used.

The normal eye data 212a of the present embodiment includes graph information (standard graph) representing a standard distribution of characteristic values. The standard graph is defined using a coordinate system including a first coordinate axis that represents the position of the eye in a predetermined range and a second coordinate value that represents the magnitude of the characteristic value. The standard graph of the present embodiment represents an allowable range of characteristic values for determining a normal eye. The predetermined range of the eye is included in the target range of the OCT scan. Here, the predetermined range and the target range may be the same or different. For example, the predetermined range may be a two-dimensional area composed of a part of a three-dimensional area that is a target of a three-dimensional scan. The first coordinate axis includes one or more coordinate axes. For example, when the first coordinate axis includes a single coordinate axis, the first coordinate axis represents a one-dimensional position, for example, a plurality of positions arranged on a straight line or in a curved line. When the first coordinate axis is composed of two coordinate axes, the first coordinate axis represents a two-dimensional position, for example, a plurality of positions arranged on a plane or a curved surface. The same applies to the case where the first coordinate axis is composed of three or more coordinate axes.

An example of a standard graph is shown in FIG. The standard graph 300 represents a standard distribution of retinal nerve fiber layer (cpRNFL) thickness around the optic disc. The horizontal axis corresponds to the first coordinate axis and represents the definition area of the standard graph 300. The vertical axis corresponds to the second coordinate axis and represents the value of the thickness of the retinal nerve fiber layer.

The domain defined by the horizontal axis is the circumference of a cylindrical area surrounding the optic disc and having a predetermined diameter. An example is shown in FIG. In this example, a circular scan path P having a predetermined diameter is applied around the optic disc D. OCT is sequentially performed on a plurality of positions on the scan path P. Center P _C of the circular scan path P is set in the center of example approximate circle (approximate ellipse) of the center of gravity or the optic nerve head D of the optic disc D. The diameter of the scan path P may be a default value. Alternatively, the diameter of the scan path P may be set for each eye E based on the diameter of the optic nerve head D (disk diameter, cup diameter, rim diameter, etc.). As a specific example, the diameter of the scan path P can be obtained by multiplying the measured value of the diameter of the optic nerve head D by a predetermined constant.

In FIG. 5, “T” is the ear side (temporal), “S” is the upper side (superior), “N” is the nasal side (nasal), “I” is the lower side (inferior), respectively. Show. “T”, “S”, “N”, and “I” attached to the horizontal axis in FIG. 4 correspond to these directions. A standard graph 300 shown in FIG. 4 shows a standard thickness of the retinal nerve fiber layer in a two-dimensional section obtained by cutting a cylindrical section around the optic nerve head along the z-direction at the position of the ear side “T”. Represents a significant distribution.

The standard graph 300 in this example may represent the allowable range of the layer thickness value at each point (each point on the horizontal axis) on the circumference (scan path P). In this case, the standard graph 300 includes, for example, a graph (average graph) 301 indicating the average value of the layer thickness at each point on the circumference, a graph (upper limit graph) 302 indicating the upper limit of the allowable range, and a graph indicating the lower limit. (Lower limit graph) 303. In addition, the standard graph 300 is obtained by measuring a large number of normal eyes, collecting distribution graphs of the thickness of the retinal nerve fiber layer, and analyzing the thickness distribution modes (shape, position, value size, etc.). It is also possible to form. In this case, the standard graph 300 represents not a standard distribution of layer thickness values but a form that can be taken by a normal eye distribution graph (that is, an allowable range of the distribution graph form). It is also possible to create the distribution graph 300 in consideration of both the layer thickness value and the form of the distribution graph.

<Image forming unit 220>
The image forming unit 220 forms image data of a cross-sectional image of the fundus oculi Ef or the anterior ocular segment based on the sampling result of the detection signal input from the DAQ 130. This processing includes signal processing such as noise removal (noise reduction), filter processing, and FFT (Fast Fourier Transform) as in the case of the conventional swept source OCT. The image data formed by the image forming unit 220 is a group of image data (a group of image data) formed by imaging reflection intensity profiles in a plurality of A lines (lines in the z direction) arranged along the scan line. A scan image data).

The image forming unit 220 includes, for example, at least one of a processor and a dedicated circuit board. In the present specification, “image data” and “image” based thereon may be identified. Further, the part of the eye E to be examined and the image representing it may be identified.

<Data processing unit 230>
The data processing unit 230 performs image processing and analysis processing on the image formed by the image forming unit 220. For example, the data processing unit 230 executes correction processing such as image luminance correction and dispersion correction. Further, the data processing unit 230 performs image processing and analysis processing on an image (fundus image, anterior eye image, etc.) obtained by the fundus camera unit 2. The data processing unit 230 includes, for example, at least one of a processor and a dedicated circuit board. The data processing unit 230 includes a three-dimensional image forming unit 231, a partial image specifying unit 232, a characteristic value calculating unit 233, a distribution graph creating unit 234, and a graph comparing unit 235.

<Three-dimensional image forming unit 231>
When a three-dimensional scan (raster scan or the like) of the eye E is performed, the image forming unit 220 forms a two-dimensional cross-sectional image (B scan image) corresponding to each scanning line. The three-dimensional image forming unit 231 forms a three-dimensional image based on these two-dimensional cross-sectional images. A three-dimensional image means image data in which pixel positions are defined by a three-dimensional coordinate system. Examples of 3D images include stack data and volume data.

Stack data is image data obtained by three-dimensionally arranging a plurality of cross-sectional images corresponding to a plurality of scanning lines based on the positional relationship of these scanning lines. That is, stack data is image data obtained by expressing a plurality of cross-sectional images originally defined by individual two-dimensional coordinate systems by a single three-dimensional coordinate system (that is, by embedding them in one three-dimensional space). is there.

Volume data (voxel data) is formed by executing known image processing such as interpolation processing for interpolating pixels between a plurality of cross-sectional images included in the stack data to form voxels. A pseudo three-dimensional image (rendered image) is formed by performing rendering processing (volume rendering, MIP (Maximum Intensity Projection), etc.) on the volume data. A two-dimensional cross-sectional image can be formed from a group of pixels arranged in an arbitrary cross section in the volume data. This image processing is called multi-planar reconstruction (MPR).

<Partial image specifying unit 232>
When the three-dimensional image forming unit 231 forms a three-dimensional image of the eye E, the partial image specifying unit 232 analyzes the three-dimensional image, thereby comparing the three-dimensional image with the normal eye data 212a. Identify the partial image inside. As described above, the normal eye data 212a includes a standard graph. The partial image specifying unit 232 specifies an area in the three-dimensional image corresponding to the definition area (predetermined range of the eye described above) indicated by the first coordinate axis of the standard graph.

A specific example will be described. When the standard graph 300 shown in FIG. 4 is applied, an OCT scan of a three-dimensional region including the optic disc D and its periphery is executed to form a three-dimensional image. The partial image specifying unit 232 specifies a partial image corresponding to the scan path P shown in FIG. 5 by analyzing the three-dimensional image. A specific example of this processing is shown in FIG. A symbol V indicates a three-dimensional image. The partial image specifying unit 232 specifies the optic disc D by analyzing the three-dimensional image V, and specifies the scan path P based on the position and diameter of the specified optic disc D. The scanning path P is a circle that surrounds the optic nerve head D and has a predetermined diameter. The partial image corresponding to the scan path P is a cylindrical cross-sectional image G having the scan path P as a circumference and the z direction as an axial direction.

<Characteristic Value Calculation Unit 233>
The characteristic value calculation unit 233 calculates the characteristic value at each of a plurality of positions in the target region by analyzing the partial image specified by the partial image specifying unit 232. In this example, the characteristic value calculation unit 233 determines the thickness distribution of the retinal nerve fiber layer by analyzing the cylindrical cross-sectional image G. That is, the thickness of the retinal nerve fiber layer is measured at a plurality of positions in the scan path P.

For this purpose, the characteristic value calculation unit 233 first cuts the cylindrical cross-sectional image G along the z direction at the ear position “T”. Thus, a two-dimensional cross-sectional image G _A as shown in FIG. 7 is obtained. Next, the characteristic value calculating unit 233, by performing segmentation of two-dimensional cross-sectional images G _A, image regions (nerve fiber layer image) corresponding to the retinal nerve fiber layer to identify the L. Segmentation is performed based on changes in pixel values, as in the conventional case. For example, the segmentation is performed so that a characteristic value is specified from the values of the pixel group arranged in each A line, and a pixel having the specified value is selected as a pixel of a predetermined layer (or its boundary). . In the segmentation, the characteristic value calculation unit 233 may obtain an approximate curve (a linear approximate curve, a logarithmic approximate curve, a polynomial approximate curve, a power approximate curve, an exponential approximate curve, a moving average approximate curve, etc.) of the layer boundary.

Furthermore, the characteristic value calculating unit 233, each position on the scan path _{P p m (m = 1,2,} ···, M) for, the nerve fiber layer image L in the A line passing through the position _{p m} thick W (p _m ) is obtained. Thereby, a plurality of positions _p 1 on the scan path _P, p 2, · · ·, the thickness of the retinal nerve fiber layer in _{_{_{p M W (p 1),}}} W (p 2), ···, W (p _M ) is obtained. That is, the thickness distribution W (P) of the retinal nerve fiber layer along the scan path P is obtained.

<Distribution graph creation unit 234>
The distribution graph creation unit 234 creates a distribution graph based on the characteristic values calculated for a plurality of positions by the characteristic value calculation unit 233. In this example, the distribution graph creation unit 234 represents a coordinate system in which the position on the scan path P is represented by the horizontal axis (first coordinate axis) and the thickness W of the retinal nerve fiber layer is represented by the vertical axis (second coordinate axis). The correspondence relationship (p _m , W (p _m )) obtained by the characteristic value calculation unit 233 is plotted. The distribution graph creation unit 234 can connect a plurality of points plotted in the coordinate system with broken lines or curves. By such processing, a distribution graph H shown in FIG. 8 is created.

<Graph Comparison Unit 235>
The graph comparison unit 235 compares the distribution graph H created by the distribution graph creation unit 234 with the standard graph 300 stored in the storage unit 212a. In this example, the graph comparison unit 235 determines whether or not the distribution graph H is included in the allowable range represented by the standard graph 300. An example of comparison between the distribution graph H and the standard graph 300 is shown in FIG. In the example illustrated in FIG. 9, the distribution graph H is included in an allowable range (a region sandwiched between the upper limit graph 302 and the lower limit graph 303 illustrated in FIG. 4) indicated by the standard graph 300. Therefore, the result of this comparative diagnosis is determined to be normal.

The method of comparing the graphs is arbitrary. For example, it is configured to determine whether or not the entire distribution graph is included in the allowable range represented by the standard graph, or to be configured to determine whether or not at least a part of the distribution graph is included in the allowable range represented by the standard graph, The distribution graph included in the allowable range represented by the standard graph can be configured to determine whether the ratio is equal to or greater than a threshold value.

Also, it can be configured to determine whether or not the distribution graph has the characteristics of the standard graph. For example, the retinal nerve fiber layer thickness (cpRNFLT) around the nipple of normal eyes becomes thinner in the order of lower side, upper side, nose side, and ear side (ISNT's law), and in the vicinity of “I” and “S” in the graph Each has a convex portion (called double hump). It is known that the double hump shape collapses in glaucomatous eyes. Therefore, it is possible to create a standard graph in consideration of the allowable range of the interval between the two convex portions, the allowable range of the displacement of the convex portions, the allowable range of the elevation difference between the convex portions and other portions, and the like. .

Also, both graphs can be recognized as images and the image correlation between them can be obtained. The value of the image correlation is used as a deviation of the distribution graph with respect to the standard graph, and serves as a determination material for determining whether or not there is an abnormality in the eye E.

Both graphs are regarded as thickness distribution functions in a space (WP space) spanned by the layer thickness (W) and the position on the scan path (P), and a correlation between these distribution functions is obtained. be able to. The correlation value between the distribution functions is obtained as a cross-correlation function of the graph of the eye E to be examined with respect to the standard graph, and is used as a material for determining the presence / absence and degree of abnormality based on comparison with a standard normal eye.

<User Interface 240>
The user interface 240 includes a display unit 241 and an operation unit 242. The display unit 241 includes the display device 3. The main control unit 211 causes the display unit 241 to display information obtained by the data processing unit 230. For example, the comparison result between the standard graph and the distribution graph and information indicating whether or not an abnormality has been found in the eye E can be displayed. The operation unit 242 includes various operation devices and input devices. The user interface 240 may include a device such as a touch panel in which a display function and an operation function are integrated. Embodiments that do not include at least a portion of the user interface 240 can also be constructed. For example, the display device may be an external device connected to the ophthalmologic apparatus.

<Operation>
The operation of the ophthalmologic apparatus 1 will be described. An example of the operation is shown in FIG.

(S1: Perform 3D OCT scan)
First, OCT of the eye E is performed. In this example, data is collected by scanning a three-dimensional region including the optic papilla D shown in FIG. 5 and its periphery (including at least the scan path P). This three-dimensional scan is, for example, a raster scan in which a plurality of linear scanning lines are arranged in parallel to each other. Each scanning line has, for example, a line segment shape extending in the x direction, and the plurality of scanning lines are arranged at equal intervals in the y direction.

(S2: Form a plurality of B-scan images)
The image forming unit 220 forms a plurality of B scan images corresponding to the plurality of scanning lines based on the data collected in step S1. The B scan image of this example is, for example, a two-dimensional cross-sectional image representing an xz cross section.

(S3: Form a three-dimensional image)
The three-dimensional image forming unit 231 forms a three-dimensional image (three-dimensional image V shown in FIG. 6) based on the plurality of B scan images formed in step S2.

(S4: Specify a partial image)
The partial region specifying unit 232 specifies the cylindrical cross-sectional image G (partial image of the three-dimensional image V) including the optic nerve head D and having a predetermined diameter by analyzing the three-dimensional image V formed in step S3. To do.

(S5: Calculate characteristic value)
The characteristic value calculation unit 233 calculates the thickness (characteristic value) of the retinal nerve fiber layer at a plurality of positions on the scan path P by analyzing the cylindrical cross-sectional image G identified in step S4. Specifically, the characteristic value calculating unit 233 forms a 2-dimensional cross-sectional image G _A shown in FIG. 7 by cutting open along the z-direction a cylindrical cross-sectional image G ear-side position in the "T", the two-dimensional cross-section performing segmentation of the image G _a identifies the nerve fiber layer image L by. Furthermore, the characteristic value calculating unit 233, for each position _{p m} on the scan path P, determining the thickness W of the nerve fiber layer image L in the A line passing through the position _{p m} _{(p m).} Thereby, the thickness distribution W (P) = {W (p ₁ ), W (p ₂ ),..., W (p _M )} of the retinal nerve fiber layer along the scan path P is obtained.

(S6: Create a distribution graph)
The distribution graph creation unit 234 takes the position of the retinal nerve fiber layer obtained in step S5 in the coordinate system having the position on the scan path P on the horizontal axis and the thickness W of the retinal nerve fiber layer on the vertical axis. The height distribution W (P) = {W (p ₁ ), W (p ₂ ),..., W (p _M )} is plotted. Thereby, the distribution graph H shown in FIG. 8 is obtained.

(S7: Compare the distribution graph with the standard graph)
The graph comparison unit 235 compares the distribution graph H created in step S6 with the standard graph 300 (see FIG. 4) stored in advance in the storage unit 212a, thereby determining whether or not there is a disease (such as glaucoma). A determination is made.

(S8: Output the comparison result)
The main control unit 211 causes the display unit 241 to display the comparison result (presence / absence of disease, degree, etc.) obtained in step S7. The output method of the comparison result is not limited to display, and may be, for example, transmission to an external computer or storage device, recording on a recording medium, printing on a printing medium, or the like.

<Modification>
Several modifications of the above embodiment will be described. Unless otherwise specified, the same reference numerals are used for elements having the same or similar functions as those in the above embodiment in the following description of the modified examples.

FIG. 11 shows a part of an ophthalmologic apparatus according to a modification. A data processing unit 230A shown in FIG. 11 is applied instead of the data processing unit 230 (see FIG. 3) of the above embodiment. That is, the ophthalmologic apparatus of the present modification includes the configuration shown in FIGS. 1 and 2, the elements shown in FIG. 3 other than the data processing unit 230, and the data processing unit 230A shown in FIG.

The data processing unit 230A includes a three-dimensional image forming unit 231A, a characteristic value calculating unit 232A, a characteristic value selecting unit 233A, a distribution graph creating unit 234A, and a graph comparing unit 235A. The three-dimensional image forming unit 231A is configured to execute the same processing as the three-dimensional image forming unit 231 of the above embodiment.

The characteristic value calculation unit 232A calculates the characteristic value at each of a plurality of positions of the three-dimensional image by analyzing the three-dimensional image formed by the three-dimensional image forming unit 231A. For example, the characteristic value calculation unit 232A calculates the thickness of the retinal nerve fiber layer for all the A lines constituting the three-dimensional image. Thereby, the thickness distribution of the retinal nerve fiber layer in the three-dimensional region where the three-dimensional OCT scan is performed is obtained.

The characteristic value selection unit 233A selects a characteristic value corresponding to the target part from all the characteristic values obtained by the characteristic value calculation unit 232A by analyzing the three-dimensional image. For this purpose, the characteristic value selection unit 233A specifies, for example, a partial image in the three-dimensional image corresponding to the target part. This process is executed, for example, in the same manner as the partial image specifying unit 232 of the above embodiment. Thereby, for example, characteristic values (thicknesses of the retinal nerve fiber layer) at a plurality of positions in the region represented by the cylindrical cross-sectional image G shown in FIG. 6 are selected.

The distribution graph creation unit 234A creates a distribution graph in which the distribution of the characteristic values in the target part is expressed by a predetermined coordinate system based on the characteristic value group selected by the characteristic value selection unit 233A. This process is executed in the same manner as the distribution graph creation unit 234 of the above embodiment. Thereby, for example, a distribution graph H as shown in FIG. 8 is obtained.

The graph comparison unit 235A compares the distribution graph created by the distribution graph creation unit 234A with the standard graph stored in advance in the storage unit 212. This process is executed in the same manner as the graph comparison unit 235 of the above embodiment.

Thus, the combination and order of a series of processes based on a three-dimensional image obtained by a three-dimensional OCT scan may be arbitrary. In addition, before forming a three-dimensional image, a partial image (such as a nerve fiber layer image) may be specified and a characteristic value may be calculated. For example, a B-scan image used for forming a three-dimensional image can be analyzed to identify a partial image or calculate a characteristic value.

Also, there is no need to perform a 3D OCT scan. For example, only the target site of the comparative diagnosis may be OCT scanned. For example, in the case shown in FIG. 5, it is possible to apply a circle scan for the scan path P. In such a case, it is not necessary to form a three-dimensional image. In addition, when an OCT scan is performed only on the target part, it is not necessary to specify a partial image.

<Action and effect>
The operation and effect of the ophthalmologic apparatus according to the embodiment and its modification will be described. Further modifications will be described.

The ophthalmologic apparatus includes a storage unit, a data collection unit, a processing unit, a comparison unit, and an output unit. The storage unit displays a standard graph in which a standard distribution of characteristic values is expressed by a coordinate system including a first coordinate axis representing a position in a predetermined range of the eye and a second coordinate axis representing a magnitude of the predetermined characteristic value of the eye. Store in advance. The storage unit 212 of the above embodiment is an example. The data collection unit collects data of the region of the eye to be examined including the target region corresponding to the predetermined range using OCT. In the above-described embodiment, the elements in the OCT unit 100 and the elements arranged in the measurement arm among the elements in the fundus camera unit 2 are included in the data collection unit. The processing unit processes the collected data to create a distribution graph in which the distribution of characteristic values in the target region is expressed by the coordinate system. In the above embodiment, the image forming unit 220 and elements (at least the characteristic value calculating unit 233 and the distribution graph creating unit 234) that contribute to creating the distribution graph among the elements in the data processing unit 230 are included in the processing unit. . The comparison unit compares the distribution graph created by the processing unit with the standard graph. The comparison unit 235 of the above embodiment is an example. The output unit outputs a comparison result between the distribution graph and the standard graph. The main control unit 211 and the display unit 241 of the above embodiment are examples thereof.

The processing unit may include an image forming unit, a characteristic value calculating unit, and a distribution graph creating unit. The image forming unit is configured to form an image based on the data collected by the data collecting unit. This image is, for example, a two-dimensional image (B-scan image or the like) or a three-dimensional image. The image forming unit 220 (and the three-dimensional image forming unit 231) of the above embodiment is an example. The characteristic value calculation unit is configured to calculate characteristic values at each of a plurality of positions in the target site of the comparative diagnosis by analyzing the image formed by the image forming unit. The characteristic value calculation unit 233 of the above embodiment is an example. The distribution graph creation unit is configured to create a distribution graph based on the characteristic values calculated for a plurality of positions (distribution of characteristic values in the target part). The distribution creation unit 234 of the above embodiment is an example.

The domain of the standard graph (the predetermined range above) may be a cylindrical range surrounding the optic nerve head and having a predetermined diameter. In that case, the characteristic value calculation unit may be configured to calculate the thickness of the layer tissue including the retinal nerve fiber layer as the characteristic value. Further, the distribution graph creation unit expresses the distribution of the thickness of the layer structure in a coordinate system in which a plurality of positions in the circumferential direction in the cylindrical range are represented by the first coordinate axis and the thickness of the layer structure is represented by the second coordinate axis. Thus, a distribution graph may be created.

The data collection unit may be configured to scan a three-dimensional region of the eye to be examined that includes a target region corresponding to the definition region (the predetermined range) of the standard graph. In that case, it is possible to configure as follows. The image forming unit forms a three-dimensional image based on data collected by scanning the three-dimensional region. The processing unit includes a first specifying unit that specifies a partial image corresponding to the target region by analyzing the formed three-dimensional image. The partial image specifying unit 232 of the above embodiment is an example. The characteristic value calculation unit calculates the characteristic value by analyzing the specified partial image. The distribution graph creation unit creates a distribution graph based on the characteristic values acquired for the partial images.

As another example when the data collection unit scans a three-dimensional area, the following configuration can be adopted. The image forming unit forms a three-dimensional image based on data collected by scanning the three-dimensional region. The characteristic value calculation unit calculates the characteristic value by analyzing the formed three-dimensional image. The processing unit includes a second specifying unit that specifies a characteristic value corresponding to the target part among the characteristic values obtained by the characteristic value calculating unit by analyzing the three-dimensional image. The characteristic value selection unit 233A of the modification is an example. The distribution graph creation unit creates a distribution graph based on the specified characteristic value.

According to the above-described embodiments and modifications, a comparative diagnosis of ophthalmic diseases (diagnosis of whether or not the disease is present, the degree of progression of the disease, etc.) based on the degree of coincidence of the distribution graph with respect to the standard graph (degree of deviation) )It can be performed. Therefore, it is not necessary to perform registration between the layer thickness distribution of the eye to be examined and the standard layer thickness distribution, and the diagnosis result is not affected by the accuracy and accuracy of registration. In addition, compared with the conventional method of comparing the absolute value of the tissue thickness or the like with the standard value, the influence of individual differences on the diagnosis result is small. Therefore, according to the embodiment and the modification, it is possible to improve the accuracy of the comparative diagnosis using the standard data.

In other words, unlike the conventional method for locally determining whether or not the characteristic value of the eye to be examined is normal (locally), the embodiment and the modified example globally (globally) distribute the characteristic state of the eye to be examined. ) Is configured to determine. When data is not acquired locally due to the presence of blood vessels, or when accurate data is not acquired locally due to measurement noise or the like, comparative diagnosis of the part cannot be performed with the conventional method. According to this, it is possible to obtain a result by a global comparative diagnosis.

In addition, according to the embodiment and the modification, it is also possible to detect an abnormality that is difficult to grasp by a conventional method such as a double hump shape collapse in a glaucoma eye or the like. It is known that the distance between two humps (convex portions) tends to increase when the eye to be examined is a myopic eye (high-strength myopia). According to the embodiment and the modification, it is possible to make a comparative diagnosis by referring to the distance between the humps, or to determine whether the eye to be examined is a myopic eye based on the distance between the humps. .

In addition, there is an advantage in the conventional method for locally comparing the characteristic value with the standard value. Therefore, it is possible to combine the conventional method and the method of the said embodiment and modification. In this case, the storage unit (for example, the storage unit 212) stores in advance the allowable range of the characteristic value in addition to the standard graph. The allowable range of characteristic values is normal eye data used in conventional comparative diagnosis, and is map information representing, for example, allowable ranges of characteristic values at a plurality of positions of the eye (characteristic value ranges for normal eyes).

It is possible to sequentially perform a conventional comparative diagnosis and a comparative diagnosis such as an embodiment. For example, it is possible to first execute a conventional comparative diagnosis and perform a comparative diagnosis of the embodiment or the like according to the result. For example, when the characteristic value (or at least a part thereof) obtained by the processing unit is included in the allowable range (that is, when it is determined to be a normal value), the comparison unit performs comparison diagnosis (distribution graph and (Compared to a standard graph). The conventional comparative diagnosis is executed by the data processing unit 230 and the like in the same manner as in the past. On the other hand, when the characteristic value (or at least a part thereof) obtained by the processing unit is not included in the allowable range (that is, when it is determined to be an abnormal value), the main control unit 211 indicates that an abnormality exists. Can be output by the display unit 241 or the like.

A specific example will be described. First, the data processing unit 230 performs a conventional comparative diagnosis on the thickness of the retinal nerve fiber layer, and determines whether or not there is a site (abnormal site) having a thickness outside the allowable range. When it is determined that there is no abnormal site, the graph comparison unit 235 compares the distribution graph with the standard graph. By performing the two-stage comparative diagnosis in this way, the possibility of false negatives is reduced. On the other hand, when it is determined that an abnormal site exists, the comparison process between the distribution graph and the standard graph is omitted.

Note that the order in which these comparative diagnoses are performed may be reversed. For example, it is possible to determine whether or not to execute the conventional comparative diagnosis according to the result of the comparative diagnosis of the embodiment or the modification. In addition, the results may be output by comprehensively considering the results of the comparative diagnosis of the embodiment or the modified example and the results of the conventional comparative diagnosis. For example, it can be configured to output the result “abnormal” when it is determined to be abnormal in one or both of the comparative diagnoses, and to output the result “normal” when it is determined to be normal in both of the comparative diagnoses. Further, the result may be output in consideration of the degree of abnormality in both comparative diagnoses.

Although the ophthalmologic apparatus of the above-described embodiment or modification includes a configuration (data collection unit) for executing OCT, the embodiment is not limited to this. For example, the embodiment may be an ophthalmic modality other than OCT, a computer, or the like. In this case, data obtained using OCT is input from the outside. Such an ophthalmologic apparatus includes a storage unit, a reception unit, a processing unit, a comparison unit, and an output unit.

Similar to the above embodiment, the storage unit has a standard distribution of characteristic values by a coordinate system including a first coordinate axis that represents a position in a predetermined range of the eye and a second coordinate axis that represents the magnitude of the predetermined characteristic value of the eye. Is stored in advance.

The accepting unit accepts data collected by scanning the region of the eye to be examined including the target region corresponding to the predetermined range by OCT. The reception unit is, for example, a communication interface in the arithmetic control unit 200 of the above embodiment. The communication interface receives data from an external device via a communication line such as the Internet or a LAN. The external device is, for example, a computer (server, storage device, etc.) on a communication line. The accepting unit is not limited to the communication interface. For example, the reception unit may include a drive device that reads data recorded on the recording medium.

The processing unit processes the data received by the receiving unit to create a distribution graph in which the distribution of characteristic values in the target region is expressed by the coordinate system. The comparison unit compares the created distribution graph with the standard graph. The output unit outputs a comparison result between the distribution graph and the standard graph. Here, each of the processing unit, the comparison unit, and the output unit may have the same configuration as in the above embodiment.

Even in such an embodiment, it is possible to improve the accuracy of comparative diagnosis using standard data, as in the above-described embodiments and modifications.

The embodiment described above is merely an example of the present invention. A person who intends to implement the present invention can arbitrarily make modifications (omission, substitution, addition, etc.) within the scope of the present invention.

1 Ophthalmic Device 100 OCT Unit 212 Storage Unit 212a Normal Eye Data 220 Image Forming Unit 230 Data Processing Unit 234 Distribution Graph Creation Unit 235 Graph Comparison Unit

Claims

A standard graph in which a standard distribution of the characteristic values is expressed by a coordinate system including a first coordinate axis representing a position in a predetermined range of the eye and a second coordinate axis representing the magnitude of the predetermined characteristic value of the eye is stored in advance. A storage unit;
A data collection unit that collects data of a region of the eye to be examined including a target region corresponding to the predetermined range using optical coherence tomography;
By processing the collected data, a processing unit that creates a distribution graph in which the distribution of the characteristic values in the target part is expressed by the coordinate system;
A comparison unit for comparing the created distribution graph and the standard graph;
An ophthalmologic apparatus comprising: an output unit that outputs a comparison result between the distribution graph and the standard graph.
The processor is
An image forming unit that forms an image based on the data collected by the data collecting unit;
A characteristic value calculation unit that calculates the characteristic value at each of a plurality of positions in the target region by analyzing the formed image;
The ophthalmic apparatus according to claim 1, further comprising: a distribution graph creating unit that creates the distribution graph based on the characteristic values calculated for the plurality of positions.
The predetermined range is a cylindrical range surrounding the optic nerve head and having a predetermined diameter,
The characteristic value calculation unit calculates the thickness of the layer tissue including the retinal nerve fiber layer as the characteristic value,
The distribution graph creation unit is configured to distribute the thickness of the layer structure in a coordinate system in which a plurality of circumferential positions in the cylindrical range are represented by the first coordinate axis and the thickness of the layer structure is represented by the second coordinate axis. The ophthalmic apparatus according to claim 2, wherein the distribution graph is created by expressing
The data collection unit scans a three-dimensional region of the eye to be examined including the target region,
The image forming unit forms a three-dimensional image based on data collected by scanning the three-dimensional region;
The processing unit includes a first specifying unit that specifies a partial image corresponding to the target region by analyzing the formed three-dimensional image,
The characteristic value calculation unit calculates the characteristic value by analyzing the specified partial image,
The ophthalmologic apparatus according to claim 2, wherein the distribution graph creation unit creates the distribution graph based on the characteristic value acquired for the partial image.
The data collection unit scans a three-dimensional region of the eye to be examined including the target region,
The image forming unit forms a three-dimensional image based on data collected by scanning the three-dimensional region;
The characteristic value calculation unit calculates the characteristic value by analyzing the formed three-dimensional image,
The processing unit includes a second specifying unit that specifies a characteristic value corresponding to the target portion among the characteristic values obtained by the characteristic value calculating unit by analyzing the three-dimensional image,
The ophthalmologic apparatus according to claim 2, wherein the distribution graph creating unit creates the distribution graph based on the specified characteristic value.
The storage unit stores an allowable range of the characteristic value in advance,
6. The comparison unit according to claim 1, wherein when the characteristic value obtained by the processing unit is included in the allowable range, the comparison unit compares the distribution graph with the standard graph. The ophthalmic device described.
The ophthalmologic apparatus according to claim 6, wherein the output unit outputs abnormality information when the characteristic value obtained by the processing unit is not included in the allowable range.
A standard graph in which a standard distribution of the characteristic values is expressed by a coordinate system including a first coordinate axis representing a position in a predetermined range of the eye and a second coordinate axis representing the magnitude of the predetermined characteristic value of the eye is stored in advance. A storage unit;
A reception unit that receives data collected by scanning an area of the eye to be examined including a target region corresponding to the predetermined range by optical coherence tomography;
By processing the received data, a processing unit that creates a distribution graph in which the distribution of the characteristic values in the target part is expressed by the coordinate system;
A comparison unit for comparing the created distribution graph and the standard graph;
An ophthalmologic apparatus comprising: an output unit that outputs a comparison result between the distribution graph and the standard graph.