JP2023059992A - Ophthalmologic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To estimate a refraction degree of an eye at a time different from the time when the refraction degree is measured.

SOLUTION: A refraction measurement unit in an ophthalmologic apparatus according to an embodiment measures the refraction degree of a subject eye objectively. An OCT unit applies OCT scan to an ocular fundus of the subject eye to acquire OCT data. A time recording unit records a time (measurement time) when the OCT scan was performed. A layer position data acquisition unit analyzes the OCT data to acquire layer position data including positional data of the front face and the rear face of the choroid of the ocular fundus. A data processing unit obtains choroid thickness data from the layer position data and calculates an estimate value of the refraction degree of the subject eye at a predetermined time on the basis of at least standard data of circadian variation in choroid thickness obtained by periodical regression analysis with the choroid thickness as a variable, the measurement time, measurement data acquired by the refraction measurement unit, and the choroid thickness data.

SELECTED DRAWING: Figure 4

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present invention relates to an ophthalmic apparatus for determining a refractive power representing the refractive state of an eye.

It is known that the refractive power of the eye varies during the day due to various factors. Therefore, strictly speaking, the optimum power of corrective devices such as spectacles and contact lenses varies depending on the time of day. For example, the optimum power of spectacles during the day and the optimum power at night are strictly different. A refractometer is generally used to measure the refractive power of the eye.

It is known that the tissue of the fundus also has circadian variations. For example, research on diurnal variations in choroidal thickness is underway (see, for example, Non-Patent Documents 1 and 2). In addition, it is conceivable that the position of the retina changes with changes in choroidal thickness.

There are subjective refraction measurement and objective refraction measurement as methods for examining the refraction power of an eye (see Patent Documents 1 and 2, for example). A subjective refraction measurement is a subjective test that determines the refractive power of an eye to be examined according to the subject's response to a visual target (such as the Landolt's ring) presented to the eye to be examined. Objective refraction measurement is an objective test that determines the refractive power of an eye to be inspected based on changes in the size and shape of the reflected light image of the light projected onto the fundus of the eye to be inspected.

JP 2016-077774 A JP 2017-080135 A

Shinichi Usui et al., “Circadian Changes in Subfoveal Choroidal Thickness and the Relationship with Circulatory Factors in Healthy Subjects”, Investigative Ophthalmology & Visual Science, April 2012, Vol. 53, No.4, pp. 2300-2307 Colin S. Tan et al., “Diurnal Variation of Choroidal Thickness in Normal, Healthy Subjects Measured by Spectral Domain Optical Coherence Tomography”, Investigative Ophthalmology & Visual Science, January 2012, Vol. 53, No.1, pp. 261-266

Since the visual target (visible light) presented to the subject's eye in subjective refraction measurement is detected by photoreceptor cells, the subjective refractive power is approximately from the corneal surface to the junction of the inner and outer segments of the photoreceptors (IS/OS). It can be said that it represents the refractive power in the range up to the vicinity. Therefore, if the position of IS/OS varies during the day, it is considered that the subjective refractive power also varies during the day. Optical coherence tomography (OCT) is known as a technique for acquiring information along the depth direction of the fundus. By specifying the positions of IS/OS from a plurality of OCT images of the fundus acquired at various times, it is possible to detect subjective diurnal variations in refractive power.

On the other hand, in the objective refraction measurement, since the reflected light from the fundus is detected, the contribution of the reflected light from the tissue with high reflectance among the fundus tissues is considered to be large. Typically, tissues from the photoreceptor outer segment (OS) to the retinal pigment epithelium (RPE) are considered to greatly affect the measurement results.

In addition, since near-infrared light is used in objective refraction measurement, it is believed that reflection from a region (for example, the choroid) deeper than the visual cells that detect visible light also contributes to the measurement results. Especially when the choroid is thin, reflection of light reaching the sclera may affect the measurement results.

In this way, there is a difference between the subjectively obtained refractive power and the objectively obtained refractive power due to the difference in measurement principle.

Moreover, in order to measure the diurnal variation of the refractive power, it is necessary to perform the measurement at least every several hours.

An object of the present invention is to estimate the refractive power at a time different from the time at which the refractive power was measured.

An ophthalmic device according to some exemplary embodiments includes a refraction measurement unit, an OCT unit, a time recording unit, a layer position data acquisition unit, and a data processing unit. The refraction measuring unit objectively measures the refractive power of the subject's eye. The OCT unit obtains OCT data by applying an optical coherence tomography (OCT) scan to the fundus of the subject's eye. The time recording unit records the measurement time, which is the time when the OCT scan was performed by the OCT unit. The layer position data acquisition unit acquires layer position data including position data of the anterior surface of the choroid of the fundus and position data of the posterior surface of the choroid by analyzing the OCT data. The data processing unit calculates choroid thickness data based on the layer position data. Furthermore, the data processing unit stores standard data of diurnal variation in choroidal thickness obtained by periodic regression analysis with at least the choroidal thickness as a variable, the measurement time recorded by the time recording unit, and the measurement obtained by the refraction measurement unit. Based on the data and the thickness data of the choroid, an estimated refractive power of the subject's eye at a predetermined time is calculated.

According to embodiments, it is possible to estimate the refractive power at a time different from the time at which the refractive power was measured.

1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 4 is a flow chart illustrating an example of the operation of an ophthalmic device according to an exemplary embodiment; 4 is a flow chart illustrating an example of the operation of an ophthalmic device according to an exemplary embodiment; 1 is a schematic diagram illustrating an example configuration of an ophthalmic apparatus according to an exemplary embodiment; FIG. 4 is a flow chart illustrating an example of the operation of an ophthalmic device according to an exemplary embodiment;

An ophthalmic device according to some exemplary embodiments will be described in detail with reference to the drawings.

First, an outline of the embodiment will be described. An ophthalmologic apparatus according to an embodiment acquires objective refraction power of an eye to be inspected and OCT data of a fundus, analyzes the OCT data, acquires position data (layer position data) of a predetermined layer of the fundus, and obtains objective refraction It is configured to generate refractive power data for the subject's eye based at least on the power and the layer position data.

Acquisition of the objective refraction power may be, for example, either measurement by an objective refraction measuring device or reception of objective refraction power data from an electronic medical record system or the like. Similarly, acquisition of OCT data may be, for example, either measurement by an OCT device (OCT scan and image data construction), or reception of OCT data from a medical image archiving system or the like.

The ophthalmic device of the embodiment may include one or both of an objective refraction measuring device and an OCT device. Further, the ophthalmologic apparatus of the embodiment may include a device (communication interface, input/output interface, etc.) that receives data from an external device or recording medium.

Thus, the ophthalmic device of the embodiment may be, for example, any of the following: (A) an examination device including an objective refraction measurement device (refraction measurement section) and an OCT device (OCT section); ) An examination apparatus that includes an objective refraction measurement device (refraction measurement section) and does not include an OCT device (OCT section); (C) An OCT device (OCT section) that does not include an objective refraction measurement device (refraction measurement section) (D) an information processing device that does not include either an objective refraction measurement device (refraction measurement section) or an OCT device (OCT section).

An ophthalmic device of an embodiment includes: a processor programmed to analyze OCT data to generate layer position data; and a processor programmed to generate refractive power data based at least on the objective refractive power and the layer position data. a processor; These processors may be the same hardware or separate hardware.

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 (for example, an SPLD (Simple Programmable Logic De vice), CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array)) or the like. A processor, for example, implements a specific function by reading and executing a program stored in a memory circuit or memory device.

The refractive power data generated by the ophthalmologic apparatus of the embodiment may be any data that can be used or referred to as the refractive power of the subject's eye. For example, the refraction power data of the embodiment may be a correction value (correction value of objective refraction power) based on measurement data of objective refraction power. Furthermore, the correction value of the objective refraction power may be the subjective refraction power (estimated value). Alternatively, the refraction power data of the embodiment may be the objective refraction power (estimated value) at another time based on the objective refraction power obtained by the measurement performed at a certain time.

In this specification, unless otherwise specified, no distinction is made between "image data" and "images" based thereon. In addition, unless otherwise specified, the site or tissue of the subject's eye is not distinguished from the image representing it.

<First Embodiment>
<Configuration>
FIG. 1 shows a configuration example of an ophthalmologic apparatus according to an embodiment. The ophthalmologic apparatus 1 is an apparatus of type (A) described above, that is, an examination apparatus including an objective refraction measurement apparatus (refraction measurement section) and an OCT apparatus (OCT section). The ophthalmologic apparatus 1 includes a refraction measurement section 10 , an OCT section 20 and a computer 30 . The computer 30 includes a layer position data acquisition section 40 , a data processing section 50 and a control section 60 .

The refraction measuring unit 10 objectively measures the refractive power of the eye E to be examined. The refraction measuring unit 10 has, for example, a configuration similar to that of a known refractometer. Although not shown, a typical refractometer includes a projection system, a light receiving system, and a processor, as disclosed in US Pat.

The projection system of the refraction measuring unit 10 projects the light emitted from the light source onto the fundus Ef of the eye E to be examined. The projection system, for example, projects light from the light source onto the fundus oculi Ef through a collimator lens, a focusing lens, a relay lens, a pupil lens, a perforated prism, a decentered prism, an objective lens, and the like.

The light receiving system of the refraction measuring unit 10 receives the reflected light from the fundus oculi Ef through an objective lens, a decentered prism, a perforated prism, another pupil lens, another relay lens, another focusing lens, a conical prism, an imaging lens, and the like. projected onto the image sensor. Thereby, the ring pattern is detected by the imaging device.

The processor of the refraction measurement unit 10 is programmed to process the output from the imaging device of the light receiving system and calculate the objective refraction power. A process of obtaining the displacement (positional deviation, deformation, etc.) and a process of obtaining the objective refraction power (measurement data) from this displacement are executed.

The OCT unit 20 acquires OCT data by applying an OCT scan to the fundus oculi Ef. The OCT data may be interference signal data, reflection intensity profile data obtained by applying a Fourier transform to the interference signal data, or image data obtained by applying image representation to the reflection intensity profile data. .

The OCT technique that the OCT section 20 can perform is typically Fourier domain OCT, and may be either spectral domain OCT or swept source OCT. The swept source OCT splits the light from the wavelength tunable light source into measurement light and reference light, and superimposes the return light of the measurement light projected on the test object with the reference light to generate interference light. is detected by a photodetector, and Fourier transform or the like is performed on detection data (interference signal data) collected according to wavelength sweeping and measurement light scanning to form reflection intensity profile data. On the other hand, spectral domain OCT divides light from a low-coherence light source (broadband light source) into measurement light and reference light, and superimposes the return light of the measurement light projected on the test object with the reference light to generate interference light. A spectral distribution of this interference light is detected by a spectroscope, and the data detected by the spectroscope (interference signal data) is subjected to Fourier transform or the like to form reflection intensity profile data. That is, the swept-source OCT is an OCT technique that acquires the spectral distribution by time division, and the spectral domain OCT is an OCT technique that acquires the spectral distribution by spatial division.

The OCT section 20 has, for example, a configuration similar to that of a known OCT apparatus. Although illustration is omitted, a typical OCT apparatus includes a light source, an interference optical system, a scanning system, a detection system, and a processor, as disclosed in Patent Documents 1 and 2.

Light output from the light source is split into measurement light and reference light by an interference optical system. A reference beam is guided by the reference arm. The measurement light is projected onto the fundus oculi Ef through the measurement arm. A scanning system is provided on the measurement arm. The scanning system includes, for example, a galvanometer scanner, and can deflect measurement light two-dimensionally.

The measurement light projected onto the fundus oculi Ef is reflected and scattered at various depth positions (layer boundaries, etc.) of the fundus oculi Ef. The return light of the measurement light from the subject's eye E is combined with the reference light by the interference optical system. The return light of the measurement light and the reference light generate interference light according to the principle of superposition. This interference light is detected by a detection system. The detection system typically includes a spectrometer for spectral-domain OCT and a balanced photodiode and data acquisition system (DAQ) for swept-source OCT.

The processor of the OCT section 20 constructs OCT data (typically image data) based on the detection data from the detection system. Similar to conventional OCT data processing, the processor applies filtering, fast Fourier transform (FFT), etc. to the detection data to obtain reflection intensity profile data for each A line (the path of the measurement light in the eye E). to build. Further, the processor constructs image data (A-scan data) for each A-line by applying imaging processing (image representation) to this reflection intensity profile data.

The processor can construct B-scan data by arranging a plurality of A-scan data according to the scanning mode of the scanning system. The processor can construct stack data by arranging a plurality of B-scan data according to the scan mode of the scan system. A processor can construct volume data (voxel data) from the stack data. The processor can render stack data or volume data. Rendering techniques include volume rendering, multiplanar reconstruction (MPR), surface rendering, and projection.

The computer 30 executes various calculations and various controls for operating the ophthalmologic apparatus 1 . Computer 30 includes one or more processors and one or more storage devices. Storage devices include random access memory (RAM), read only memory (ROM), hard disk drive (HDD), solid state drive (SSD), and the like. Various computer programs are stored in the storage device, and the calculation and control according to this example are realized by the processor operating based on the programs. In this example, with such a configuration, the processor functions as each of the layer position data acquisition section 40 , the data processing section 50 , and the control section 60 .

The layer position data acquisition unit 40 acquires layer position data of the fundus oculi Ef by analyzing the OCT data acquired by the OCT unit 20 . The layer position data includes position data for each of one or more layers of the fundus oculi Ef. Each of the one or more layers corresponds to tissues or tissue boundaries of the fundus oculi Ef. The tissues of the fundus oculi Ef include the inner limiting membrane, nerve fiber layer, ganglion cell layer, inner reticular layer, inner granular layer, outer reticular layer, outer granular layer, outer limiting membrane, photoreceptor layer, retinal pigment epithelial layer, and choroid. , sclera, etc. are known. Layer position data includes position data for a predetermined layer. This layer can be arbitrarily determined and can be, for example, IS/OS, RPE, choroid, sclera, and the like.

The process of identifying layers from OCT data typically includes segmentation. Segmentation is a known process for identifying subregions in image data. The layer position data acquisition unit 40 performs segmentation, for example, based on the luminance value of the OCT image data. That is, each layer structure of the fundus oculi Ef has a characteristic reflectance, and the image regions corresponding to these layer structures also have characteristic luminance values. The layer position data acquisition unit 40 can specify a target image region (layer) by executing segmentation based on these characteristic luminance values.

The data processing unit 50 calculates refraction power data of the subject's eye E based on at least the objective refraction power (measurement data) acquired by the refraction measurement unit 10 and the layer position data acquired by the layer position data acquisition unit 40. to generate An example of processing executed by the data processing unit 50 will be described later.

As described above, the refractive power data obtained by the data processing unit 50 may be any data that can be used or referred to as the refractive power of the eye E to be examined. Specifically, the refraction power data includes a correction value of the objective refraction power (for example, an estimated value of the subjective refraction power), and an estimated value of the objective refraction power at a time different from the time when the measurement is performed by the refraction measuring unit 10. , and an estimated value of the perceived refraction at a time different from the time at which the refraction measurement unit 10 performs the measurement.

The control section 60 controls each section of the ophthalmologic apparatus 1 . The control unit 60 can control a display device (not shown). The display device functions as part of the user interface and displays information under the control of the control section 60 . The display device may be, for example, a liquid crystal display (LCD) or an organic light emitting diode (OLED) display.

The control unit 60 can control the ophthalmologic apparatus 1 according to signals from an operation device (not shown). The operation device functions as part of the user interface section. The operation device may include various hardware keys (joystick, button, switch, etc.) provided on the ophthalmologic apparatus 1 . The operation device may also include various peripherals (keyboard, mouse, joystick, operation panel, etc.) connected to the ophthalmologic apparatus 1 . The operation device may also include various software keys (buttons, icons, menus, etc.) displayed on the touch panel.

The ophthalmic device 1 may be configured to determine refractive power data from the thickness of one or more layers of the fundus oculi Ef. For example, the layer position data acquisition unit 40 acquires layer position data including position data of the first layer and position data of the second layer of the fundus oculi Ef. Each of the first layer and the second layer may be a predetermined layer.

Furthermore, the data processing unit 50 obtains distance data between the first layer and the second layer based on this layer position data. This processing is typically performed based on the number of pixels existing between the first layer and the second layer and a predetermined inter-pixel distance. Distance measurements are taken along a given direction. The distance measurement direction may be, for example, a direction determined by OCT scanning (eg, the traveling direction of measurement light) or a direction determined based on OCT data (eg, a direction perpendicular to the layer). Further, the distance data may be distance distribution data between the first layer and the second layer, or statistical values calculated from this distance distribution data (for example, average, maximum value, minimum value, median value, mode value, variance, standard deviation), or distance data between a representative point on the first layer and a representative point on the second layer.

Subsequently, the data processing unit 50 generates refraction power data of the subject's eye E based at least on the objective refraction power measurement data acquired by the refraction measurement unit 10 and the distance data obtained from the layer position data. do. Thus, the ophthalmologic apparatus 1 can obtain refractive power data from the thickness of one or more layers of the fundus oculi Ef.

The thickness of the layer of the fundus oculi Ef referred to for obtaining the refractive power data may be the choroidal thickness, which is known to vary within the day. For example, the layer position data acquisition unit 40 identifies the anterior and posterior surfaces of the choroid of the fundus oculi Ef, and generates layer position data including position data of the anterior choroidal surface and position data of the posterior choroidal surface.

Further, the data processing unit 50 obtains distance data between the anterior choroidal surface and the posterior choroidal surface based on the position data of the anterior choroidal surface and the positional data of the posterior choroidal surface. This distance data is choroidal thickness data. The choroidal thickness data may be thickness distribution data, statistical values calculated from this thickness distribution data, or representative thickness data.

Subsequently, the data processing unit 50 generates refraction power data of the subject's eye E based at least on the objective refraction power measurement data acquired by the refraction measurement unit 10 and the choroid thickness data. Thus, the ophthalmologic apparatus 1 can obtain refractive power data from the choroidal thickness of the fundus oculi Ef.

The ophthalmologic apparatus 1 can obtain the correction value of the objective refraction power based on the choroidal thickness of the eye E to be examined. Some examples are described below. In each example, the data processing unit 50 obtains an estimated value of the subjective refraction power of the subject's eye E based on at least the measurement data of the objective refraction power acquired by the refraction measurement unit 10 and the thickness data of the choroid. configured to Here, the data processing unit 50 may be configured to convert the objective refraction power into the subjective refraction power using a correction formula having at least the choroidal thickness as a variable. This correction formula may be, for example, a linear correction formula, but may also be a non-linear correction formula. In each of the following examples, a case in which an estimated value of subjective refraction is obtained as a correction value of objective refraction will be particularly described, but the correction value of objective refraction is not limited to the estimated value of subjective refraction. , may be a value obtained by applying arbitrary correction processing to the objective refraction power (measurement data).

A first example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. The data processing unit 50 of the present example calculates the thickness of the eye to be inspected E Obtain an estimate of the perceived refraction of .

In this example, the estimated value of the subjective refraction power is obtained by scaling (linear correction) the objective refraction power with the choroidal thickness (CT) as a variable. The objective refractive power (OR) is, for example, spherical power (S) or spherical equivalent power (SE).

A linear correction formula applicable in this example may be the following conversion formula for converting objective refraction (OR) to subjective refraction (SR): SR=OR+b(CT ). Here, b(CT) is a function that determines the correction amount, with the choroidal thickness (CT) as a variable. The objective refraction power measurement data (OR) acquired by the refraction measuring unit 10 and the correction amount b(CT) corresponding to the value (CT) indicated in the choroidal thickness data of the eye E to be examined are combined into the correction formula , an estimated value (SR) of the subjective refraction power of the subject's eye E is obtained.

Another linear correction formula applicable in this example is: SR=OR*c(CT). Here, c(CT) is a function that determines the correction ratio with the choroidal thickness (CT) as a variable. The objective refraction power measurement data (OR) acquired by the refraction measuring unit 10 and the correction ratio c(CT) corresponding to the value (CT) indicated in the choroidal thickness data of the eye E to be examined are combined into the correction formula , an estimated value (SR) of the subjective refraction power of the subject's eye E is obtained.

It is also possible to combine the above two examples and apply the following linear correction formula: SR=OR*c(CT)+b(CT). Measurement data (OR) of the objective refraction power acquired by the refraction measurement unit 10, a correction ratio c (CT) corresponding to the value (CT) indicated in the thickness data of the choroid of the eye E to be examined, and this thickness data By substituting the correction amount b(CT) corresponding to the value (CT) shown in (1) into the correction formula, an estimated value (SR) of the subjective refractive power of the subject's eye E is obtained.

Note that it is also possible to apply a correction formula similar to the correction formula according to this example to calculations other than the estimation of the subjective refraction power. The same applies to the following.

A second example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. Different choroidal thicknesses may affect the conversion of refractive power differently. For example, it may not be appropriate to apply the same conversion formula (correction formula) to both an eye with a particularly thin choroid and an eye with a particularly thick choroid. From this point of view, it is possible to divide the choroidal thickness value into a plurality of ranges, provide correction formulas corresponding to each range, and selectively apply these correction formulas.

A specific example will be described. The data processing unit 50 of this example stores in advance two or more correction formulas corresponding to two or more ranges of choroidal thickness values, respectively. The data processing unit 50 selects a correction formula corresponding to the thickness data of the choroid of the subject's eye E from among these correction formulas. The selection of this correction formula is, for example, a process of selecting a range to which the choroidal thickness value indicated in the choroidal thickness data of the eye E to be examined belongs from two or more ranges of the choroidal thickness value, and and identifying a correction formula corresponding to the range. Further, the data processing unit 50 obtains an estimated value of the subjective refraction power of the subject's eye E by inputting the measurement data of the objective refraction power acquired by the refraction measurement unit 10 into the selected correction formula.

_SR One of _m =OR+ _bm ( _CTm ), _SRm =OR* _cm ( _CTm ), and _SRm =OR* _cm ( _CTm )+ _bm ( _CTm ) is prepared. Here, it is assumed that SR _m =OR+b _m (CT _m ) is stored in the data processing unit 50 .

The data processing unit 50 determines to which of two or more ranges CT _m the value indicated by the choroidal thickness data obtained from the OCT data acquired by the OCT unit 20 belongs. For example, if the value indicated by the choroidal thickness data belongs to the range CT ₁ , _the data processing unit 50 selects the correction formula SR ₁ =OR+b ₁ (CT ₁ ). Further, the data processing unit 50 adds the objective refraction measurement data (OR) acquired by the refraction measurement unit 10 to the selected correction formula SR ₁ =OR+b ₁ (CT ₁ ) and the choroidal By substituting the correction amount b ₁ (CT ₁ ) corresponding to the value indicated by the thickness data, an estimated value (SR ₁ ) of the subjective refraction power of the subject's eye E is obtained.

A third example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. The variable for linear correction is not limited to choroidal thickness alone. For example, the data processing unit 50, based on a predetermined correction formula in which the choroidal thickness and the refractive power are variables, objective refractive power measurement data acquired by the refraction measuring unit 10, and choroidal thickness data, It may be configured to obtain an estimated value of the subjective refraction power of the eye E to be examined.

In this example, the estimated value of the perceived refraction power is obtained by scaling (linear correction) the objective refraction power using the choroidal thickness (CT) and the objective refraction power (OR) as variables.

A linear correction formula applicable in this example may be the following conversion formula for converting objective refraction (OR) to subjective refraction (SR): SR=OR+b(CT,OR) . Here, b(CT, OR) is a function that determines the amount of correction using the choroidal thickness (CT) and the objective refraction power (OR) as variables. Correction amount b (CT , OR) into the correction formula, an estimated value (SR) of the subjective refractive power of the subject's eye E is obtained.

Another linear correction formula applicable in this example is: SR=OR*c(CT,OR). Here, c(CT, OR) is a function that determines the correction ratio, with the choroidal thickness (CT) and the objective refraction power (OR) as variables. Correction ratio c (CT , OR) into the correction formula, an estimated value (SR) of the subjective refractive power of the subject's eye E is obtained.

It is also possible to combine the above two examples and apply the following linear correction formula: SR=OR*c(CT,OR)+b(CT,OR). Correction ratio c (CT , OR) and the correction amount b (CT, OR) corresponding to the value (CT) indicated in the thickness data and the measurement data (OR) into the correction formula, the subjective refraction of the subject eye E A frequency estimate (SR) is obtained.

A fourth example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. From the same point of view as in the second example, it is possible to divide the choroidal thickness value into a plurality of ranges, provide correction formulas corresponding to each range, and selectively apply these correction formulas. The correction formula of this example is a predetermined correction formula that uses the choroidal thickness and the refractive power as variables, as described in the third example.

A specific example will be described. The data processing unit 50 of this example stores in advance two or more correction formulas corresponding to two or more ranges of choroidal thickness values, respectively. The data processing unit 50 selects a correction formula corresponding to the thickness data of the choroid of the subject's eye E from among these correction formulas. Furthermore, the data processing unit 50 inputs, for example, objective refraction measurement data acquired by the refraction measurement unit 10 and choroid thickness data of the subject's eye E to the selected correction formula, An estimated value of the subjective refraction power of eye examination E is obtained.

A fifth example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. The choroidal thickness is not the only factor that affects the conversion of refractive power. For example, refractive power can affect conversion. For example, it may not be appropriate to apply the same conversion formula (correction formula) to both an eye with a particularly small refractive power and an eye with a particularly large refractive power. From this point of view, it is possible to divide the refractive power values into a plurality of ranges, provide correction formulas corresponding to the respective ranges, and selectively apply these correction formulas. The correction formula of this example is a predetermined correction formula that uses the choroidal thickness and the refractive power as variables, as described in the third example.

A specific example will be described. The data processing unit 50 of this example stores in advance two or more correction formulas respectively corresponding to two or more ranges of refractive power values. The data processing unit 50 selects, from among these correction formulas, a correction formula corresponding to the measurement data of the objective refraction power acquired by the refraction measurement unit 10 . Furthermore, the data processing unit 50 inputs, for example, objective refraction measurement data acquired by the refraction measurement unit 10 and choroid thickness data of the subject's eye E to the selected correction formula, An estimated value of the subjective refraction power of eye examination E is obtained.

A sixth example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. In this example, a combination of the fourth example and the fifth example will be described. That is, it is possible to classify the choroidal thickness values into a plurality of ranges and classify the refractive power values into a plurality of ranges, provide a correction formula for each combination of both classes, and selectively apply these correction formulas. . The correction formula of this example is a predetermined correction formula that uses the choroidal thickness and the refractive power as variables, as described in the third example.

A specific example will be described. First, for each combination of two or more ranges of choroidal thickness values and two or more ranges of refractive power values, corresponding correction formulas are prepared. In this example, four or more correction formulas are stored in the data processing unit 50 . The data processing unit 50 selects a correction formula corresponding to a combination of the thickness data of the choroid of the eye E to be examined and the measurement data of the objective refraction power of the eye E to be examined from among these correction formulas. Furthermore, the data processing unit 50 inputs, for example, the measurement data of the objective refraction power of the eye to be examined E and the thickness data of the choroid of the eye to be examined E into the selected correction formula, so that the awareness of the eye to be examined E is corrected. Obtain an estimate of the refractive power.

A seventh example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. The ophthalmologic apparatus 1 of this example further includes a function of acquiring axial length data of the subject's eye E (an axial length data acquiring unit). Acquisition of axial length data may be, for example, either measurement by an axial length measuring device or reception of axial length data from an electronic medical record system or the like.

The method for measuring the axial length of the eye may be, for example, a method using OCT as disclosed in Patent Documents 1 and 2. That is, it is possible to obtain the axial length by specifying the corneal vertex position and the retinal surface position based on the OCT data and calculating the distance between these positions. Note that the method for measuring the axial length of the eye is not limited to this, and other known methods using ultrasound, for example, may be used.

Now, variables for linear correction are not limited to choroidal thickness and refractive power. The data processing unit 50 of this example includes a predetermined correction formula having variables of the choroidal thickness and the axial length, measurement data of the objective refraction power acquired by the refraction measuring unit 10, choroidal thickness data, and axial Based on the long data, an estimated value of the subjective refractive power of the subject's eye E is obtained.

In this example, the estimated value of the subjective refraction power is obtained by scaling (linear correction) the objective refraction power using the choroidal thickness (CT) and the axial length (AL) as variables.

A linear correction formula applicable in this example may be the following conversion formula for converting objective refraction (OR) to subjective refraction (SR): SR=OR+b(CT,AL) . Here, b(CT, AL) is a function that determines the amount of correction using the choroidal thickness (CT) and the axial length (AL) as variables. A correction amount b corresponding to the measurement data (OR) of the objective refraction power acquired by the refraction measurement unit 10, the value (CT) indicated by the thickness data of the choroid of the eye E to be examined, and the axial length data (AL) By substituting (CT, AL) into the correction formula, an estimated value (SR) of the subjective refractive power of the subject's eye E is obtained.

Another linear correction formula applicable in this example is: SR=OR*c(CT, AL). Here, c(CT, AL) is a function that determines the correction ratio with variables of choroidal thickness (CT) and axial length (AL). Correction ratio c corresponding to measurement data (OR) of objective refraction power acquired by refraction measurement unit 10, value (CT) indicated by thickness data of choroid of eye E to be examined, and axial length data (AL) By substituting (CT, AL) into the correction formula, an estimated value (SR) of the subjective refractive power of the subject's eye E is obtained.

It is also possible to combine the above two examples and apply the following linear correction formula: SR=OR*c(CT, AL)+b(CT, AL). Correction ratio c corresponding to measurement data (OR) of objective refraction power acquired by refraction measurement unit 10, value (CT) indicated by thickness data of choroid of eye E to be examined, and axial length data (AL) (CT, AL) and the correction amount b (CT, AL) corresponding to the value (CT) and the axial length data (AL) shown in the thickness data are substituted into the correction formula, thereby obtaining An estimate of the perceived refraction of E (SR) is obtained.

An eighth example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. From the same point of view as in the second example, it is possible to divide the choroidal thickness value into a plurality of ranges, provide correction formulas corresponding to each range, and selectively apply these correction formulas. The correction formula of this example is a predetermined correction formula that uses the choroidal thickness and the axial length as variables, as described in the seventh example.

A specific example will be described. The data processing unit 50 of this example stores in advance two or more correction formulas corresponding to two or more ranges of choroidal thickness values, respectively. The data processing unit 50 selects a correction formula corresponding to the thickness data of the choroid of the subject's eye E from among these correction formulas. Furthermore, the data processing unit 50 inputs, for example, objective refraction measurement data acquired by the refraction measurement unit 10 and choroid thickness data of the subject's eye E to the selected correction formula, An estimated value of the subjective refraction power of eye examination E is obtained.

A ninth example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. Choroidal thickness and refractive power are not the only factors that affect the conversion of refractive power. For example, axial length can affect conversion. It is known that the axial length of the eye affects the refractive power. For example, eyes with particularly long axial lengths tend to be highly myopic. Therefore, it may not be appropriate to apply the same conversion formula (correction formula) to both an eye with a particularly long axial length and an eye with a particularly short axial length. From this point of view, it is possible to divide the axial length value into a plurality of ranges, provide correction formulas corresponding to each range, and selectively apply these correction formulas. The correction formula of this example is a predetermined correction formula that uses the choroidal thickness and the axial length as variables, as described in the seventh example.

A specific example will be described. The data processing unit 50 of this example stores in advance two or more correction formulas respectively corresponding to two or more ranges of axial length values. The data processing unit 50 selects, from among these correction formulas, a correction formula corresponding to the axial length data acquired by the axial length data acquisition unit. Furthermore, the data processing unit 50 inputs, for example, objective refraction measurement data acquired by the refraction measurement unit 10 and choroid thickness data of the subject's eye E to the selected correction formula, An estimated value of the subjective refraction power of eye examination E is obtained.

A tenth example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. In this example, a combination of the eighth example and the ninth example will be described. That is, it is possible to classify the choroidal thickness value into a plurality of ranges and classify the eye axial length value into a plurality of ranges, provide a correction formula for each combination of both classes, and selectively apply these correction formulas. be. The correction formula of this example is a predetermined correction formula that uses the choroidal thickness and the axial length as variables, as described in the seventh example.

A specific example will be described. First, for each combination of two or more ranges of choroidal thickness values and two or more ranges of axial length values, corresponding correction formulas are prepared. In this example, four or more correction formulas are stored in the data processing unit 50 . The data processing unit 50 selects a correction formula corresponding to a combination of the thickness data of the choroid of the eye E to be examined and the axial length data of the eye E to be examined from among these correction formulas. Furthermore, the data processing unit 50 inputs, for example, the measurement data of the objective refraction power of the eye to be examined E and the thickness data of the choroid of the eye to be examined E into the selected correction formula, so that the awareness of the eye to be examined E is corrected. Obtain an estimate of the refractive power.

An eleventh example of processing for estimating the subjective refractive power based on the choroidal thickness will be described. This example is a combination of the third example and the seventh example. The data processing unit 50 of this example stores a predetermined correction formula including three variables of choroidal thickness, refractive power, and axial length, objective refractive power measurement data acquired by the refraction measuring unit 10, and choroidal thickness. It is configured to obtain an estimated value of the subjective refractive power of the subject's eye E based on the data and the axial length data.

In this example, the choroidal thickness (CT), objective refraction power (OR), and axial length (AL) are variables, and the objective refraction power is scaled (linearly corrected) to obtain an estimated value of the perceived refraction power.

A linear correction formula applicable in this example may be the following conversion formula for converting objective refraction (OR) to subjective refraction (SR): SR=OR+b(CT,OR, A. L.). Here, b(CT, OR, AL) is a function that determines the amount of correction using choroidal thickness (CT), objective refraction power (OR), and axial length (AL) as variables. Objective refraction power measurement data (OR) acquired by the refraction measurement unit 10, the value (CT) indicated by the thickness data of the choroid of the subject's eye E, the measurement data (OR), and the axial length data (AL) By substituting the correction amount b (CT, OR, AL) corresponding to , into the correction formula, an estimated value (SR) of the subjective refractive power of the subject's eye E is obtained.

Although details are omitted, other linear correction formulas applicable to this example include SR=OR×c(CT, OR, AL) and SR=OR×c(CT, OR, AL)+b(CT, OR, AL). Here, c(CT, OR, AL) is a function that determines the correction ratio, with variables of choroidal thickness (CT), objective refraction power (OR), and axial length (AL).

Similarly, although details are omitted, each of the choroidal thickness value, refractive power value, and axial length value is divided into a plurality of ranges, correction formulas are provided for each combination of these divisions, and these correction formulas are selectively applied. Is possible. The correction formula of this example is a predetermined correction formula having variables of choroidal thickness, refractive power, and axial length.

<Action>
The operation of the ophthalmologic apparatus 1 according to this embodiment will be described. An example of the operation of the ophthalmologic apparatus 1 is shown in FIGS. 2 and 3. FIG. The flowchart of FIG. 2 shows an example of operation when the axial length data is not used, and the flowchart of FIG. 3 shows an example of operation when the axial length data is used.

First, the operation example shown in FIG. 2 will be described.

(S1: objective refraction measurement)
In step S<b>1 of this example, objective refraction measurement of the subject's eye E is performed using the refraction measurement unit 10 of the ophthalmologic apparatus 1 .

(S2: OCT scan of fundus)
In step S2 of this example, an OCT scan is applied to the fundus oculi Ef using the OCT unit 20 of the ophthalmologic apparatus 1 to obtain OCT data.

Note that the OCT scan may be performed before the objective refraction measurement, or the objective refraction measurement and the OCT scan may be performed in parallel.

Although illustration is omitted, the ophthalmologic apparatus 1 may have a function of presenting the subject with a fixation target for guiding the line of sight of the eye E to be examined. The fixation target may be an internal fixation target presented to the subject's eye E, or an external fixation target presented to the fellow eye. Objective refraction measurements and OCT scans can be performed under the same fixation position.

(S3: Obtain layer position data from OCT data)
The layer position data acquisition unit 40 acquires layer position data of the fundus oculi Ef by analyzing the OCT data acquired in step S2.

(S4: Estimation of Perceived Refractive Power)
The data processing unit 50 estimates the subjective refraction power of the eye to be inspected E based on at least the measurement data of the objective refraction power of the eye to be inspected E acquired in step S1 and the layer position data acquired in step S3. Ask for It should be noted that it is also possible to obtain a correction value for the objective refraction power that is different from the estimated value for the subjective refraction power by a similar method.

Next, an operation example shown in FIG. 3 will be described. In this example, the axial length data of the eye E to be examined is referred to.

(S11: objective refraction measurement)
In step S<b>11 of this example, objective refraction measurement of the subject's eye E is performed using the refraction measurement unit 10 of the ophthalmologic apparatus 1 .

(S12: OCT scan of fundus)
In step S12 of this example, an OCT scan is applied to the fundus oculi Ef using the OCT unit 20 of the ophthalmologic apparatus 1 to obtain OCT data.

(S13: Acquire axial length data)
In step S<b>13 of this example, the axial length data of the subject's eye E is obtained using the axial length data obtaining unit of the ophthalmologic apparatus 1 .

Note that the execution order and execution timing of the three steps of objective refraction measurement, OCT scanning, and axial length data acquisition are arbitrary. In addition, objective refraction measurement, OCT scanning, and axial length measurement can be performed under the same fixation position.

(S14: Obtain layer position data from OCT data)
The layer position data acquisition unit 40 acquires layer position data of the fundus oculi Ef by analyzing the OCT data acquired in step S12.

(S15: Estimation of Perceived Refractive Power)
Based on at least the measurement data of the objective refraction power of the subject's eye E acquired in step S11, the axial length data acquired in step S13, and the layer position data acquired in step S14, the data processing unit 50 Then, an estimated value of the subjective refraction power of the subject's eye E is obtained. It should be noted that it is also possible to obtain a correction value for the objective refraction power that is different from the estimated value for the subjective refraction power by a similar method.

<Second embodiment>
In the first embodiment, the case where the estimated value of the subjective refractive power is obtained as the refractive power data based on the choroidal thickness of the eye to be examined has been particularly described. As described above, the refraction power data may be an estimated value of the objective refraction power (or the subjective refraction power) at a time different from the time when the objective refraction measurement is performed. In this embodiment, a case will be described in which an estimated value of the objective refraction power is obtained at a time different from the time at which the objective refraction measurement is performed.

In order to obtain the estimated value of the subjective refraction at a time different from the time at which the objective refraction measurement is performed, for example, the following two steps can be applied: (First step) According to the present embodiment By executing the process, an estimated value of the objective refraction power at a time different from the execution time of the objective refraction measurement is obtained; The estimated value of the objective refraction power obtained in the step is converted into an estimated value of the subjective refraction power. Note that the process of obtaining the estimated value of the subjective refraction power at a time different from the time at which the objective refraction measurement is performed is not limited to this example.

In normal eyes, no significant diurnal variation in retinal thickness is observed, but there is significant diurnal variation in choroidal thickness. In addition, a correlation between the value (baseline) of choroidal thickness at a predetermined time and the variation range of choroidal thickness, and a correlation between the refractive power and the variation range of choroidal thickness have been reported (for example, Non-Patent Document 2 ). Examples of embodiments based on such findings are described below.

In the following description, the reference numerals used in the first embodiment are appropriately applied. In addition, in the present embodiment, descriptions of items similar to those of the first embodiment will be omitted unless otherwise noted, and items different from those of the first embodiment will be particularly described.

<Configuration>
FIG. 4 shows a configuration example of an ophthalmologic apparatus according to this embodiment. The ophthalmologic apparatus 1A includes a refraction measuring section 10, an OCT section 20, and a computer 30A. The computer 30A includes a layer position data acquisition section 40, a data processing section 50A, a control section 60, and a time recording section 70A.

The refraction measurement unit 10, the OCT unit 20, the layer position data acquisition unit 40, and the control unit 60 may each be the same as the corresponding elements in the first embodiment.

The computer 30A executes various calculations and various controls for operating the ophthalmologic apparatus 1A. Computer 30A includes one or more processors and one or more storage devices. Various computer programs are stored in the storage device, and the calculation and control according to this example are realized by the processor operating based on the programs. In this example, with such a configuration, the processor functions as each of the layer position data acquisition section 40, the data processing section 50A, the control section 60, and the time recording section 70A.

The time recording unit 70A records the time when the OCT unit 20 executes the OCT scan for obtaining the thickness data of the choroid of the eye E to be examined. This time is called measurement time.

Time recording unit 70A includes a clock unit and a recording unit. The clock section has a function of presenting the time. The clock section includes, for example, a real-time clock, a high precision event timer, a satellite positioning signal receiver, a base station signal receiver, and the like.

The recording unit records the time presented by the clock unit when a specific event occurs. That is, the recording unit records the occurrence time of a specific event. The recording unit includes a processor that can access the clock unit, and a storage device that records time data acquired by the processor from the clock unit.

The event whose occurrence time is recorded may be the time (measurement time) when the OCT section 20 executes the OCT scan for obtaining the thickness data of the choroid of the subject's eye E, as described above. Note that the measurement time is not limited to this, and may be, for example, the time when the refraction measurement unit 10 executes objective refraction measurement for obtaining the objective refraction power (measurement data) of the eye E to be examined.

In a typical embodiment, the measurements by the refraction measurement section 10 and the measurements by the OCT section 20 can be performed at substantially the same time. “Substantially the same time” means not only simultaneous time but also time difference that is permissible from the viewpoint of circadian variation of choroidal thickness (biorhythm).

Based on at least the measurement time recorded by the time recording unit 70A, the measurement data of the objective refraction power of the eye to be examined E, and the thickness data of the choroid of the eye to be examined E, the data processing unit 50A calculates the Obtain an estimate of the refractive power of E. The predetermined time can be arbitrarily set, and is set by the user or the ophthalmologic apparatus 1A, for example.

The data processing unit 50A can refer to the standard data of diurnal variations in choroidal thickness. Standard data can be obtained, for example, by regression analysis using at least choroidal thickness as a variable. Variables other than choroidal thickness include refractive power, eye axial length, age, and the like.

Regression analysis may be, for example, linear regression analysis or non-linear regression analysis. An example of nonlinear regression analysis is periodic regression analysis based on trigonometric functions. Linear regression analysis is typically used to determine standard data for a fraction of a 24-hour period. This partial period is a period in which linear approximation is possible, such as daytime or nighttime. Cyclic regression analysis is typically used to obtain standard data over periods of length (eg, full 24-hour periods) for which linear approximation cannot be satisfactorily approximated.

If a linear regression analysis is applied, the change in choroidal thickness ΔCT can be expressed, for example, as: ΔCT=axt. Here, t is the time and a is the slope of the regression line. This regression line is defined, for example, in a coordinate system in which the horizontal axis indicates the time axis and the vertical axis indicates the amount of variation in choroidal thickness.

When linear regression analysis is performed using the choroidal thickness (CT) as a variable, for example, a regression line ΔCT=a(CT)×t is used. When performing linear regression analysis using choroidal thickness (CT) and objective refraction (OR) as variables, for example, regression line ΔCT=a(CT, OR)×t is used. Here, the objective refraction power (OR) may be spherical power (S) or equivalent spherical power (SE). When performing linear regression analysis using the objective refraction power (OR) as a variable, for example, a regression line ΔCT=a(OR)×t is used.

If a periodic regression analysis is applied, the change in choroidal thickness ΔCT can be expressed, for example, as follows: ΔCT=a×sin(t). where sin() is the sine function, t is the time, and a is the amplitude. This regression curve is defined, for example, in a coordinate system in which the horizontal axis indicates the time axis and the vertical axis indicates the amount of variation in choroidal thickness.

When periodic regression analysis is performed using the choroidal thickness (CT) as a variable, for example, a regression curve ΔCT=a(CT)×sin(t) is used. When performing periodic regression analysis using choroidal thickness (CT) and objective refraction (OR) as variables, for example, regression curve ΔCT=a(CT, OR)×sin(t) is used. When periodic regression analysis is performed using the objective refraction power (OR) as a variable, for example, a regression curve ΔCT=a(OR)×sin(t) is used.

The regression lines and regression curves exemplified above are prepared in advance and used as standard data of diurnal variations in choroidal thickness. The standard data is stored, for example, in the data processing section 50A.

The data processing unit 50A obtains an estimated value of the refraction power at a predetermined time based on at least the standard data of diurnal variation of the choroidal thickness, the measurement time, the measurement data of the objective refraction power, and the thickness data of the choroid. may be configured to

For example, the data processing unit 50A can obtain an estimated value of variation in refractive power based on standard data, measurement time, and choroidal thickness data. Typically, the data processing section 50A can obtain an estimated value of the amount of variation in refractive power by applying the measurement time and the thickness data to the standard data.

Here, the data processing unit 50A performs, for example, a process of obtaining an estimated value of the variation of the choroidal thickness based on the standard data, the measurement time, and the thickness data, and based on the obtained estimated value of the variation of the choroidal thickness. and obtaining an estimated value of the amount of variation in refractive power. The former process is executed by applying the measurement time and thickness data to the standard data. The latter process is performed via a relational expression (obtained in advance) between the amount of change in choroidal thickness and the amount of change in refractive power. Assuming that the amount of variation in choroidal thickness corresponds to the amount of variation in the retina, for example, a variation of 40 micrometers in the retina corresponds to a variation in refractive power of 0.1 diopter in a typical eye.

Furthermore, the data processing unit 50A can obtain an estimated value of refraction power at a predetermined time based on the obtained estimated value of variation in refraction power and measurement data of objective refraction power. Typically, the data processing unit 50A adds the obtained estimated value of the fluctuation amount of the refraction power to the value indicated in the measurement data of the objective refraction power, thereby obtaining the estimated value of the refraction power at a predetermined time. can be asked for.

As described above, it has been reported that there is a correlation between the choroidal thickness value (baseline) at a predetermined time and the fluctuation range of the choroidal thickness. From this point of view, it is possible to provide a plurality of standard data according to the choroidal thickness value at a predetermined reference time (for example, 9:00 am) and selectively use them. Here, each of the plurality of standard data may be created by regression analysis using refractive index (OR) as a variable.

The data processing unit 50A stores in advance two or more standard data corresponding to two or more ranges of choroidal thickness values at a predetermined reference time. The data processing unit 50A selects standard data corresponding to the thickness data of the choroid of the eye E to be examined from among these standard data.

Furthermore, the data processing unit 50A stores the selected standard data, the measurement time recorded by the time recording unit 70A, the measurement data of the objective refraction power of the eye E to be examined, and the thickness data of the choroid of the eye E to be examined. Based on this, an estimated value of refractive power at a predetermined time can be obtained. This processing is executed in the manner described above.

<Action>
The operation of the ophthalmologic apparatus 1A according to this embodiment will be described. An example of the operation of the ophthalmologic apparatus 1 is shown in FIG.

(S21: objective refraction measurement)
In step S21 of this example, objective refraction measurement of the subject's eye E is performed using the refraction measurement unit 10 of the ophthalmologic apparatus 1A.

(S22: OCT scan of fundus)
In step S22 of this example, an OCT scan is applied to the fundus oculi Ef using the OCT unit 20 of the ophthalmologic apparatus 1A to obtain OCT data.

Note that the execution order and execution timing of the objective refraction measurement and the OCT scan are arbitrary. Also, objective refraction measurements and OCT scans can be performed under the same fixation position.

(S23: Record the measurement time)
In step S23 of this example, the measurement time is recorded using the time recording unit 70A of the ophthalmologic apparatus 1A.

(S24: Obtain layer position data from OCT data)
The layer position data acquisition unit 40 acquires layer position data of the fundus oculi Ef by analyzing the OCT data acquired in step S22.

(S25: Estimation of Refractive Power at Predetermined Time)
The data processing unit 50A stores the measurement time recorded in step S23, the objective refraction measurement data obtained in step S21, and the choroidal thickness data obtained from the layer position data obtained in step S24. At least based on this, an estimated value of the refractive power of the subject's eye E at a predetermined time is obtained.

〈Action and effect〉
The operation and effects of ophthalmic devices according to some exemplary embodiments will now be described.

An ophthalmologic apparatus (1, 1A) according to an exemplary embodiment includes a refraction measurement unit (10), an OCT unit (20), a layer position data acquisition unit (40), and a data processing unit (50, 50A). including. The refraction measuring unit objectively measures the refractive power of the subject's eye. The OCT unit obtains OCT data by applying an OCT scan to the fundus of the subject's eye. The layer position data acquisition unit acquires layer position data including position data for each of one or more layers of the fundus by analyzing the OCT data. The data processing unit generates refractive power data of the subject's eye based at least on the measurement data and the layer position data acquired by the refraction measurement unit.

According to such an ophthalmologic apparatus, new refractive power data can be obtained based on the measured value of the objective refractive power of the subject's eye and the position of the layer of the fundus. Therefore, it is possible to obtain refractive power data that takes into account the position of the layers of the fundus.

In the ophthalmologic apparatus (1, 1A) according to the exemplary embodiment, a layer position data acquisition unit (40) acquires layer position data including position data of the first layer and position data of the second layer of the fundus. It may be configured as follows. Furthermore, the data processing units (50, 50A) obtain distance data between the first layer and the second layer based on this layer position data, Based on at least, it may be configured to generate refractive power data for the eye to be examined.

According to such an ophthalmologic apparatus, new refractive power data can be obtained based on the distance between the two layers of the fundus and the measurement data of the objective refractive power. It is therefore possible to obtain refractive power data that takes into account the distance between the two layers of the fundus.

In the ophthalmologic apparatus (1, 1A) according to the exemplary embodiment, the layer position data acquisition unit (40) identifies a combination of the anterior and posterior surfaces of the choroid of the fundus as a combination of the first layer and the second layer, It may be configured to obtain layer position data including position data for the anterior surface and position data for the posterior choroidal surface. In addition, the data processing unit (50, 50A) performs processing for obtaining choroidal thickness data as distance data between the first layer and the second layer, measurement data of the objective refraction power, and choroidal thickness data. and generating refractive power data for the subject's eye based on at least the above.

According to such an ophthalmologic apparatus, new refractive power data can be obtained based on the thickness data of the choroid and the measurement data of the objective refractive power. Therefore, it is possible to obtain refractive power data in consideration of the choroidal thickness.

In the ophthalmologic apparatus (1) according to the exemplary embodiment, the data processing unit (50) estimates the subjective refraction power of the subject's eye ( refractive index data). It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, the subjective refraction power of the subject's eye can be estimated based on the thickness data of the choroid and the measurement data of the objective refraction power. Therefore, it is possible to determine the perceived refraction power in consideration of the choroidal thickness. Typically, it is possible to estimate the subjective refraction power by excluding the influence of the choroid and the like from the objective refraction power obtained by the objective refraction measurement using near-infrared light. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

In the ophthalmologic apparatus (1) according to the exemplary embodiment, the data processing unit (50) comprises a predetermined correction formula having at least the choroidal thickness as a variable, measurement data of the objective refraction power of the subject's eye, and the choroidal thickness of the subject's eye. and the thickness data. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, it is possible to estimate the subjective refraction power with high accuracy and precision by considering the difference in choroidal thickness. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

In an ophthalmologic apparatus (1) according to an exemplary embodiment, a data processing unit (50) selects choroidal thickness data of an eye to be examined from among two or more correction equations corresponding to two or more ranges of choroidal thickness values, respectively. and inputting at least the measurement data of the objective refraction power into the selected correction formula to obtain the estimated value of the subjective refraction power. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, it is possible to improve the accuracy and precision of estimating the subjective refractive power. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

In the ophthalmologic apparatus (1) according to the exemplary embodiment, the data processing unit (50) stores a predetermined correction formula having at least the choroidal thickness and the refractive power as variables, objective refractive power measurement data, and choroidal thickness data. may be configured to obtain an estimated value of the subjective refraction power of the eye to be examined based on. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, it is possible to improve the accuracy and precision of estimating the subjective refractive power. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

In an ophthalmologic apparatus (1) according to an exemplary embodiment, a data processing unit (50) selects choroidal thickness data of an eye to be examined from among two or more correction equations corresponding to two or more ranges of choroidal thickness values, respectively. and inputting at least the measurement data of the objective refraction power into the selected correction formula to obtain the estimated value of the subjective refraction power. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

Further, in the ophthalmologic apparatus (1) according to the exemplary embodiment, the data processing unit (50) selects objective values of the subject's eye from among two or more correction formulas corresponding to two or more ranges of refractive power values, respectively. The estimated value of the subjective refraction power may be obtained by selecting a correction formula corresponding to the measurement data of the refraction power and inputting at least the measurement data of the objective refraction power into the selected correction formula. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

Further, in the ophthalmologic apparatus (1) according to the exemplary embodiment, the data processing unit (50) corresponds to a combination of two or more ranges of choroidal thickness values and two or more ranges of refractive power values, respectively. Selecting a correction formula corresponding to a combination of choroidal thickness data of the eye to be examined and measurement data of the objective refraction power of the eye to be examined from among four or more correction formulas, and measuring at least the objective refraction power for the selected correction formula It may be configured to obtain an estimate of the perceived refraction power by inputting data. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, it is possible to further improve the accuracy and precision of estimating the subjective refraction power. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

The ophthalmologic apparatus (1) according to the exemplary embodiment may further include an axial length data acquisition unit (20, 30) for acquiring axial length data of the eye to be examined. In addition, the data processing unit (30) calculates the subjective refraction based on a predetermined correction formula with at least the choroidal thickness and the axial length as variables, the measurement data of the objective refractive power, the choroidal thickness data, and the axial length data. It may be arranged to obtain an estimate of the frequency. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, it is possible to estimate the subjective refractive power with high accuracy and precision by considering the difference in the choroidal thickness and the difference in the axial length of the eye. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

In an ophthalmologic apparatus (1) according to an exemplary embodiment, a data processing unit (50) selects choroidal thickness data of an eye to be examined from among two or more correction equations corresponding to two or more ranges of choroidal thickness values, respectively. and inputting at least the measurement data of the objective refraction power of the subject's eye into the selected correction formula to obtain the estimated value of the subjective refraction power. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

Further, in the ophthalmologic apparatus (1) according to the exemplary embodiment, the data processing unit (50) selects the value of the eye to be inspected from among two or more correction formulas corresponding to two or more ranges of values of the axial length of the eye to be examined. The estimated value of the subjective refraction power may be obtained by selecting a correction formula corresponding to the axial length data and inputting at least the measurement data of the objective refraction power of the subject's eye into the selected correction formula. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

Further, in the ophthalmologic apparatus (1) according to the exemplary embodiment, the data processing unit (50) corresponds to a combination of two or more ranges of choroidal thickness values and two or more ranges of axial length values. A correction formula corresponding to a combination of choroidal thickness data of the eye to be examined and axial length data of the eye to be examined is selected from four or more correction formulas, and at least the objective refraction power of the eye to be examined is added to the selected correction formula It may be configured to obtain an estimated value of the perceived refraction power by inputting measurement data. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, it is possible to further improve the accuracy and precision of estimating the subjective refraction power. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

The ophthalmologic apparatus (1) according to the exemplary embodiment may further include an axial length data acquisition unit (20, 30) for acquiring axial length data of the eye to be examined. In addition, the data processing unit (50) stores a predetermined correction formula having at least the choroidal thickness, refractive power and axial length as variables, measurement data of the objective refractive power of the subject's eye, data of the choroidal thickness of the subject's eye, and The estimated value of the subjective refraction power may be calculated based on the axial length data of the optometry. It should be noted that, in some exemplary embodiments, a correction value for objective refraction power that is different from the estimated value for subjective refraction power can be determined in a similar manner.

According to such an ophthalmologic apparatus, it is possible to estimate the subjective refraction power with high accuracy and precision by considering the difference in choroidal thickness, the difference in refractive power, and the difference in axial length. The same applies to the correction of the objective refraction power, which is different from the estimation of the subjective refraction power.

An ophthalmologic apparatus (1A) according to an exemplary embodiment includes a time recording unit (70A) that records measurement time, which is the time when an OCT unit (20) executes an OCT scan for obtaining choroidal thickness data of an eye to be examined. may further include In addition, the data processing unit (50A) estimates the refraction power of the subject's eye at a predetermined time ( refractive index data).

According to such an ophthalmologic apparatus, it is possible to estimate the refractive power of the subject's eye at a time different from the measurement time by considering the choroidal thickness.

In the ophthalmologic apparatus (1A) according to the exemplary embodiment, the data processing unit (50A) stores at least the standard data of diurnal variation of the choroidal thickness, the measurement time, the measurement data of the objective refraction power of the subject's eye, and the choroidal thickness of the subject's eye. and the thickness data of the refractive index at a predetermined time.

Further, the data processing unit (50A) obtains an estimated value of the variation of the refractive power based on at least the standard data of the diurnal variation of the choroidal thickness, the measurement time, and the thickness data of the choroidal thickness of the eye to be examined. and the measured data of the objective refraction power of the eye to be examined, the estimated value of the refraction power at a predetermined time may be obtained.

Further, the data processing unit (50A) obtains an estimated value of variation in choroidal thickness based on at least the standard data, the measurement time, and the thickness data of the choroidal thickness of the eye to be examined, and obtains the estimated value of variation in choroidal thickness. , and based on the obtained estimated value of variation in refractive power and measurement data of the objective refraction power of the eye to be examined, the estimated value of refractive power at a predetermined time is determined. It may be configured as follows.

According to such an ophthalmologic apparatus, it is possible to estimate the refractive power of the subject's eye at a time different from the measurement time with high accuracy and precision by taking into consideration the standard circadian variation of the choroidal thickness.

In an ophthalmologic apparatus (1A) according to an exemplary embodiment, a data processing unit (50A) selects an eye to be examined from among two or more standard data corresponding to two or more ranges of choroidal thickness values at a predetermined reference time. select the standard data corresponding to the thickness data of the choroid, and the refractive power at a predetermined time based on the selected standard data, the measurement time, the measurement data of the objective refraction power of the eye to be examined, and the thickness data of the choroid of the eye to be examined may be configured to obtain an estimate of

According to such an ophthalmologic apparatus, it is possible to perform the process of estimating the refractive power at a time different from the measurement time with higher accuracy and precision.

According to some exemplary embodiments, location information (height information) of specific layers of the fundus (retina, choroid, sclera) is used to estimate subjective refraction power from objective refraction measurement data. (more generally, correcting the objective refraction power), or estimating the refraction power for different time periods from data obtained from objective refraction measurements taken at a certain time. The specific layer position information may be the thickness of a specific fundus tissue (for example, choroidal thickness).

According to some exemplary embodiments, refractive power values are obtained that take into account the position of fundus tissue (such as the retina) and choroidal thickness. In particular, refractive power values are obtained that take into account diurnal variations in choroidal thickness.

This makes it possible to prescribe spectacles and the like that are suitable for each time period, for example, a refractive power that is suitable for daytime and a refractive power that is suitable for nighttime. It is also possible to prescribe spectacles or the like so as not to overcorrect in all time zones. In particular, in the case of over-correction for myopic eyes, it is necessary to constantly adjust the distance vision, and there is a risk that the axial length of the eye will be elongated due to the load of accommodation.

It is also possible to determine and present a range of refraction powers in consideration of diurnal fluctuations.

Thus, according to some exemplary embodiments, it is possible to solve various problems posed by conventional eye refraction measurements.

The embodiments described above are merely examples. Therefore, arbitrary modifications (omission, substitution, addition, etc.) can be made within the scope of the present invention.

The methods described in the exemplary embodiments (methods for information processing, methods for controlling ophthalmic devices, etc.) can be executed by ophthalmic devices and computers. Also, it is possible to provide a program that causes a computer to execute the method. Also, it is possible to create a computer-readable non-transitory recording medium recording such a program. This non-transitory recording medium may be in any form, examples of which include magnetic disks, optical disks, magneto-optical disks, and semiconductor memories.

1 ophthalmic apparatus 1A ophthalmic apparatus 10 refraction measurement unit 20 OCT unit 30 computer 30A computer 40 layer position data acquisition unit 50 data processing unit 50A data processing unit 60 control unit 70A time recording unit

Claims (8)

a refraction measuring unit that objectively measures the refractive power of an eye to be examined;
an OCT unit that acquires OCT data by applying an optical coherence tomography (OCT) scan to the fundus of the eye to be examined;
A time recording unit that records the measurement time, which is the time when the OCT unit executes the OCT scan;
a layer position data acquisition unit that acquires layer position data including position data of the anterior surface of the choroid of the fundus and position data of the posterior surface of the choroid by analyzing the OCT data;
The choroidal thickness data is calculated based on the layer position data, and standard data of diurnal variation in choroidal thickness obtained by periodic regression analysis with at least choroidal thickness as a variable, and recorded by the time recording unit an ophthalmologic apparatus comprising: a data processing unit that calculates an estimated value of the refractive power of the subject's eye at a predetermined time based on the measurement time, the measurement data acquired by the refraction measurement unit, and the thickness data. The data processing unit
Obtaining an estimated value of variation in refractive power based on the standard data, the measurement time, and the thickness data;
obtaining the estimated value of the refractive power of the eye to be examined at the predetermined time based on the estimated value of the variation amount and the measurement data;
The ophthalmic device of claim 1. The data processing unit
Obtaining an estimated value of variation in choroidal thickness based on the standard data, the measurement time, and the thickness data;
obtaining the estimated value of the variation in the refractive power based on the estimated value of the variation in the choroidal thickness;
obtaining the estimated value of the refractive power of the subject eye at the predetermined time based on the estimated value of the variation in the refractive power and the measurement data;
3. The ophthalmic device of claim 2. The data processing unit
selecting standard data corresponding to the thickness data from among two or more standard data corresponding to two or more ranges of choroidal thickness values at a predetermined reference time;
obtaining the estimated value of the refractive power of the subject eye at the predetermined time based on the selected standard data, the measurement time, the measurement data, and the thickness data;
The ophthalmic device according to any one of claims 1-3. The measurement data is either spherical power data or equivalent spherical power data,
The ophthalmic device according to any one of claims 1-4. The standard data is a sine function with time as a variable, having an amplitude with at least choroidal thickness as a variable,
The ophthalmic device according to any one of claims 1-5. The standard data is a sine function with time as a variable, having amplitude with choroidal thickness and objective refraction as variables,
The ophthalmic device of claim 6. the data processing unit obtains an estimated value of subjective refractive power based on the estimated value of the refractive power of the subject eye at the predetermined time;
The ophthalmic device according to any one of claims 1-7.

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