JP2812421B2 - Corneal cell imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corneal endothelium photographing apparatus for magnifying and photographing corneal endothelial cells of an eyeball of a subject.

[0002]

2. Description of the Related Art To see the effects of contact lenses,
It is necessary to observe the state of the corneal endothelial cells for medical treatment before and after the cataract surgery, and conventionally, for magnifying or photographing the corneal endothelial cells of the eyeball of the subject, The objective lens of the microscope is a non-contact type or a contact type, and the slit illumination light is irradiated from the oblique direction to the part to be observed with respect to the eye axis, and the reflected light from the cornea is enlarged and observed. By detecting the position of the light reflected from the corneal endothelium, a so-called triangulation principle is used to detect a suitable photographing position at which the corneal endothelium is focused, and photograph a corneal endothelial cell of the test portion with a television camera or the like. Is used.

[0003]

However, in these conventional apparatuses, a microscope stand provided with a television camera is manually moved in the vertical and horizontal directions by using an operating member such as a joystick. With the alignment index light positioned at the center of the pupil on the monitor screen and the eye axis of the subject and the microscope optical axis aligned,
Similarly, the gantry, which is the main body, was manually moved in the front-rear direction to focus the corneal endothelium.However, when observing or photographing with the above-described apparatus, the magnified corneal imaging site is limited to the central portion depending on the medical treatment. No, various parts were required. However, it was difficult to perform good imaging except for the central part of the cornea. In addition, for example, when imaging with various ideas, the examiner guides the visual axis at the discretion of the examiner, and it is difficult to standardize the imaging site in operation, and it is not possible to easily capture an important corneal site. Was.

The present invention has been made in view of the above points, and can guide a visual axis of a subject without requiring the judgment of an operator (examiner), and is easily important. An object of the present invention is to provide a corneal cell photographing apparatus capable of moving (switching) photographing of a photographing part capable of photographing a corneal part, and capable of performing good photographing other than at the central part of the cornea. It is intended to provide.

[0005]

In order to achieve the above object, a corneal cell photographing apparatus according to the present invention is designed to slide an eye sphere of an eye to be examined.
Illumination optical system for slit illumination, and slit that illuminates the spherical surface of the eye
The magnified image of the part to be inspected based on the illumination light
Magnifying optical system for focusing on
To receive the corneal reflected light of the slit light through the lens
Based on the set focus detection light receiving element and the anterior segment illumination light
Anterior segment imaging optical system for photographing the anterior segment of the eye
Lighting switchable with visible light source set facing
A plurality of fixation targets including the provided central target and the subject's eye
Alignment target light that projects alignment target light for
Projection means and receives corneal reflected light of the alignment index light
Corneal reflected light receiving means, and an output from the light receiving means.
Move the imaging system relative to the subject's eye
The corneal reflected light is shifted to a predetermined position on the light receiving element of the light receiving means.
Means to move the fixation target
That the predetermined position on the light receiving element can be moved.
It is a surcharge.

In the above corneal cell photographing apparatus,
In response to the lighting movement of the fixation target,
The center of curvature of the corneal endothelium of the subject's eye whose gaze is directed in the direction,
The receiver is positioned on the optical axis of the anterior segment imaging optical system.
Move a predetermined position on the optical element , and
The imaging direction is orthogonal to the corneal endothelium at the center of imaging
It is preferable to configure as follows.

[0007]

[0008]

In the above corneal cell imaging apparatus, the eyeball of the eye to be examined
Illumination optical system for slit illumination of the surface
Enlarged image of the part to be inspected based on slit illumination light
Magnifying optical system for imaging on the image receiving surface of
Also receives the corneal reflected light of the slit light through the objective lens
Focus detection light-receiving element set at a position
Anterior segment imaging optics for imaging the anterior segment based on light
And a visible light source set facing the subject's eye
A plurality of fixation targets including a switchable central target
And an alignment tool that projects alignment index light toward the subject's eye.
And a cornea for the alignment index light
A corneal reflected light receiving means for receiving the reflected light;
Move the imaging system with respect to the eye to be examined according to
The corneal reflection light of the measurement index on the light receiving element of the light receiving means
Means for positioning the fixation target at a predetermined position;
Can move a predetermined position on the light receiving element according to the light movement
According to the above, the alignment indicator light is emitted when the imaging region is moved and switched by enabling a predetermined position on the light receiving element to be movable in response to switching the lighting of the fixation target. In addition to taking an image of the anterior segment of the eye where the light spot of the photographed part is located, the photographing direction is perpendicular to the corneal surface (corneal endothelial surface or corneal epithelial surface) of the photographed region and the subject is photographed accurately. be able to.

[0009]

[0010]

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is an optical path diagram of the above-described embodiment, in which an imaging part of an eye to be inspected is moved by an operation button shown in FIG. 4 to perform imaging.

In FIG. 1, an illumination optical system for slit-illuminating the eye spherical surface 2 of the eye 1 to be inspected, and a television camera 35 can perform enlarged observation or enlarged photographing of the inspected portion based on the slit illumination light applied to the eye spherical surface 2. And a fixation target corresponding to the observation region of the eye to be examined. When the region to be examined moves along with the alignment of the optical axis of the anterior ocular segment toward the eye to be examined, the corneal reflected light reflects the corneal reflected light. An imaging system 3 including an anterior ocular imaging optical system configured to project an alignment index light onto an eye to be inspected in order to position an examination site at a predetermined position and image the corneal reflected light with a television camera 35 is shown. The photographing system 3 includes an X direction perpendicular to the optical axis 22 of the anterior ocular segment photographing optical system, a Y direction which is a vertical direction of the paper surface, and a direction of the anterior ocular segment photographing optical system optical axis 22. In three Z directions Which is moved by a driving means (not shown).

An illumination lamp 4 used at the time of focusing of an enlarged photographing optical system is used as an illumination light source of a portion to be inspected on the eye spherical surface 2.
And a strobe discharge tube 8 used at the time of taking a magnified photograph of the corneal endothelial cell, the light emitted from the cornea 2 being the observation surface of the subject's eye 1 via the projection lens 13 by the illumination optical axis 12 and The strobe discharge tube 8 is positioned at a predetermined position on the illumination optical axis 12 so that the light is emitted at a predetermined angle from the oblique direction.
The illumination lamp 4 is a half mirror 1 on the illumination optical axis 12.
1 is provided on the optical axis perpendicular to the illumination optical axis 12 via the optical axis 1.

The light emitted from the illumination lamp 4 is converged by the condensing lens 5 and a detection slit diaphragm 7 having a narrow predetermined width corresponding to a slit diaphragm 17 on the front surface of a focusing detection light-receiving element 18 described later is provided. On the other hand, the light emitted from the strobe discharge tube 8 is provided at a position where the light is focused by the condenser lens 9 with a photographing slit diaphragm 10 of a predetermined slightly wide width so as to be able to photograph in a wide field of view.
A visible light cut filter 6 is provided on the optical axis of the illumination lamp 4 in front of the eye lamp 2, and only the infrared light of the illumination lamp 4 is reflected by the half mirror 11 of infrared reflection and visible light transmission so that the eyeball 2 On the other hand, the visible light of the strobe discharge tube 8 is transmitted through the half mirror 11 to irradiate the eyeball 2.

In the optical system for photographing the anterior segment, the half mirror 23, the visible light cut filter 24, and the like are sequentially arranged at predetermined positions on the optical axis 22 of the anterior segment photographing optical system to be located on the eye axis. Anterior segment photographing lens 25 and optical axes 22 and 4
A half mirror 21 crossed by 5 ° is provided, and the CC on the front of the TV camera 35 on the rear side by the anterior segment photographing lens 25 is provided.
An anterior ocular segment image is formed on the D light receiving surface 34, and near-infrared light is projected and formed as alignment index light for alignment of a portion to be inspected which also moves while also performing optical axis alignment of a device described later. It has become. An infrared ray is provided at a predetermined position between the front of the photographing system 3 and the optical axis 22 of the anterior eye photographing optical system so as to illuminate the anterior eye from outside the optical paths of the illumination optical system and the magnifying photographing optical system described later. The light emitting diodes 33, 33 are arranged, and are turned on at the time of photographing an anterior ocular segment image.

On the opposite side of the illumination optical axis 12 of the illumination optical system and the optical axis 22 of the anterior ocular segment imaging optical system, an oblique slit-like shape formed by the illumination lamp 4 or the strobe discharge tube 8 with respect to the eye spherical surface 2 is provided. Enlarged photographing optics for receiving magnified corneal endothelial cell images of the observed portion on the image receiving surface (CCD light receiving surface) 34 of the television camera 35 by receiving the reflected light of the illumination light from the cornea and performing magnified observation or magnified photography. When the corneal endothelium image is formed on the image receiving surface 34 of the television camera 35 in a focused state, an optical axis passing through the objective lens 15 of the optical system is provided.
14 ₁ If set to extended position focus detection light receiving element 1
Reference numeral 8 detects corneal endothelium reflected light (or corneal epithelium reflected light) that moves in front of the light receiving element 18 as the imaging system 3 advances.

[0016] That is, the optical axis 14 ₁ of the enlarged image taking optical system in the anterior segment imaging optical axis 22 to the illumination optical axis 12 and symmetrically sandwiching
A predetermined position of the upper, the objective lens 15 on the eyeball surface side and a half mirror (IR transmission, visible light reflectance) at a objective lens 15 a predetermined distance 16, the optical axis 14 ₁ and a predetermined angular cross Then, the image light is reflected by the corneal reflection light of the illumination light from the eye spherical surface 2 so as to be bent so as to be orthogonal to a predetermined position on the optical axis 22 of the anterior ocular segment photographing optical system, and is reflected by the half mirror 16. and image rays of the enlarged image rays by the optical axis 14 ₂ half mirror 21 on was through the field stop 19 and the magnifying lens 20 is located on an intermediate image plane intersect the anterior segment imaging optical system optical axis 22 and 45 ° The visible light of the slit light for magnifying photographing by the strobe light is totally reflected and bent, and is incident on the image receiving surface (CCD light receiving surface) 34 of the television camera 35 provided on the optical axis 22 of the anterior ocular segment photographing optical system. , For shooting suitability detection (for focus detection) The infrared light of the slit light is
By extending the optical path of the 14 ₁ are incident on the focusing detection light receiving elements 18 provided on the imaging position of the corneal reflection image light by the objective lens 15. When the corneal endothelium image is formed in focus on the image receiving surface 34 of the television camera 35 by the objective lens 15 and the magnifying lens 20, the slit-shaped endothelial reflected light is transmitted to the corneal in front of the focus detection light-receiving element 18. Along with the slit stop 17 long in the longitudinal direction of the reflected image, the separation from the epithelial reflection that is close to the slit image is improved and incident,
The width of the light converging position of the light emitted from the illumination lamp 4 is narrowed by the slit aperture 7 and the detection slit light incident on the light receiving element 18 is used to reliably detect the corneal endothelium reflected light with good positional accuracy by the light receiving element 18. It is possible to detect a shooting compatible position (focusing position) of the device.

Further, a central fixation target a '(FIG. 3) for the subject from the side perpendicular to the optical axis 22 with respect to the half mirror 23 on the optical axis 22 of the anterior ocular segment optical system. ) And near-infrared light, which is alignment index light for matching the eye axis with the optical axis 4 for the purpose of detecting the position of the portion to be inspected. Each incident,
These rays are made to travel on the optical axis 22 of the anterior ocular segment photographing optical system and enter the ocular sphere 2. Further, the center fixation target a to be positioned on the eye axis of the eye to be examined in order to guide the gaze of the subject to move the corneal imaging region and to photograph a standardized important corneal region. ′, The fixation target c ′ located at the 4 o'clock direction at the same distance from the central fixation target a ′, b ′ located at the 6 o'clock direction,
In order to present the subject with the fixation target d 'located at 8 o'clock and the fixation target e' (see FIG. 3) located at 12 o'clock, from the outer peripheral direction of the optical axis 22 of the anterior segment imaging optical system. The eye to be examined is irradiated with visible light.

That is, a light-emitting diode 26 of near-infrared light as alignment index light and a light-emitting diode 2 of visible light as fixation target light are provided at predetermined positions on the side of the anterior ocular segment imaging optical system.
7 are disposed so that the optical axis of each light beam is parallel to the optical axis 22 of the anterior ocular segment photographing optical system. 29, near infrared light reflecting visible light transmitting mirror 30, mirror 3
1. The light is reflected by the reflection surface of the half mirror 23 through the condenser lens 32 and is incident on the ocular sphere 2 on the optical axis 22 of the anterior ocular segment imaging optical system. Visible light passes through the near-infrared light-reflecting visible light transmitting mirror 30 and, like the near-infrared light, the mirror 3
1, through the condensing lens 32 and the half mirror 23, travels on the optical axis 22 of the anterior ocular segment photographing optical system, and is projected onto the ocular sphere 2. Then, the optical axis 22 is surrounded by the optical axis 22.
Approximately equidistant from the subject at 4:00, 6:00, 8:00, 1
A predetermined position in each direction of 2:00, respectively, so as visible light emitting diodes 27 ₁ is disposed as to face the eye 1, moves before and integrally with eye imaging optical system and the magnifying imaging optical system ing. Thus, even if the imaging optical system moves for alignment or focusing, the peripheral fixation target can always be kept at a predetermined position with respect to the optical axis of the imaging optical system, and can be fixed centered with respect to the subject. The target and the peripheral fixation, which are located at approximately the same distance from the central fixation at four o'clock, six o'clock, eight o'clock, and twelve o'clock, surrounding the central fixation, are easily presented. The standardized important part of the cornea of the subject can be imaged stably. The direction and position of the peripheral fixation target can be arbitrarily selected.

Further, in the photographing system 3, by operating the operation button which is a lighting switch on the button base 36 (see FIG. 4) of the operation device (not shown), and simply pressing the record button 39,
In the fixation target, the standard position a ′ (see FIG. 3) is turned on, and the fixation target a ′ in the iris I of the anterior segment of FIG. An image of an anterior ocular segment or an enlarged image of a corneal endothelial cell at an imaging site a where the alignment index light is imaged on a monitor (not shown) connected to the television camera 23 by imaging the site a at the center of the pupil P, or You can shoot. Then, each time the change button 37 is pressed, the fixation target (fixation light) changes, for example, from a ′ → b ′ →
Switching is performed in the order of c ′ → d ′ → e ′ → a ′ (see FIG. 3). In this case, when the subject gazes at a fixation target (fixation lamp) other than the fixation target a ′ at the standard position, the observation / photographing part of the subject's eye is vertically aligned with the fixation target with respect to the pupil center part a. It is a symmetrical position in the direction. That is, when the fixation target b ′ in the 6 o'clock direction below the central standard fixation target a ′ is fixed, the observation / photographing part becomes b in the 12 o'clock direction above the pupil P, and the fixation target c in the 4 o'clock direction When fixating on ', the observation / imaging part becomes c in the 2 o'clock direction, and when fixating on the 8 o'clock direction fixation target, the observation / imaging part becomes d in the 10 o'clock direction, and the fixation target e in the 12 o'clock direction. When the 'is fixed, the observation / photographing site becomes e in the 6 o'clock direction (see FIG. 2).

Further, with the operation of the change button 37,
The display of the shooting position is displayed on an operation panel (not shown) or a monitor screen.
By selecting an appropriate position by the operation described above and pressing the record button 39, the selected position can be photographed. When the change button 37 is operated and the center button 38 is pressed at any stage, the fixation target returns to the standard position a '.

In this apparatus, a predetermined position on a light receiving element (CCD light receiving element 34 in the figure) which receives each film reflected light of the alignment index light in response to switching of the lighting of the fixation target (fixation light). Can be moved from the central position of the standard position, and when the imaging region is switched, the imaging system 3 is moved in the X direction and the Y direction so that the imaging direction is perpendicular to the corneal endothelium surface of the imaging region. The alignment target light is guided to a predetermined position on the image receiving surface, which is the alignment position, and the imaging system 3 is advanced in the Z direction while maintaining the alignment target light at the predetermined position, so that the target portion can be accurately imaged.

FIGS. 5 and 6 are light path diagrams showing the correlation between the imaging region on the corneal surface, the alignment index light position, and the fixation direction. This shows a case where the subject photographs the corneal endothelium by fixing the fixation target (fixation lamp) a ′, that is, by fixing the fixation in the direction of the photographing optical axis. At this time, in the eyeball 1 of the subject, the corneal epithelial center Q1, the corneal endothelial center Q2 and the alignment index virtual image AP are aligned on a straight line when viewed from the imaging direction P. That is, the imaging direction P, which is the imaging optical axis direction, coincides with the fixation direction S, and the corneal epithelium 2a surface having a radius r1 about the corneal epithelium center Q1 and the corneal epithelium having a radius r2 about the corneal endothelium center Q2. A line connecting the reflection point and the corneal epithelium center Q1 when the alignment index lights A, A are reflected by the corneal epithelium 2a surface and orthogonal to the endothelium 2b surface (2 in the figure)
The alignment index virtual image AP generated at the intersection of the alignment index reflected lights A ′ and A ′ that are reflected symmetrically (in dotted and dashed lines) is located on the photographing optical axis. Then, the imaging site a of the corneal endothelium 2b
Since the corneal endothelial surface 2b is orthogonal to the photographing direction P at the photographing center Pc, the region a can be photographed with high accuracy.

FIG. 6 shows a case in which the subject photographs the corneal endothelium by fixing his or her eyes below the fixation target b 'around the central fixation target (fixation lamp) a' at the standard position. At this time, the eyeball 1 of the subject rotates around the eyeball rotation point O, and the fixation direction S is
In the direction crossing the imaging direction P, the alignment parallel lights A, A can form a virtual image in the direction of the center of curvature of the corneal epithelium irrespective of the vertical direction, but the center of corneal epithelium Q1 ', the center of corneal endothelium Q2', and the alignment index light A , A are not located on a straight line when viewed from the photographing direction P. Therefore, when the alignment index virtual image AP 'is aligned with the alignment position and photographed, the corneal endothelial radius r2 is smaller than the corneal epithelial radius r1 and the photographing direction P is perpendicular to the epithelium 2a plane when the alignment position is the same as in the case of the central region photographing. Becomes the endothelium
Although the endothelial image is not well formed because it does not form a right angle with respect to the 2b plane, in this apparatus, a predetermined position on the light receiving element, which is an alignment position, can be moved in accordance with the lighting movement of the fixation target. The center of corneal endothelium Q2 'when the camera is shaken from the direction of the photographing optical axis is photographed at a position viewed from the photographing direction P.
Are orthogonal to each other, so that the corneal endothelial surface of the test portion can be favorably photographed.

In the corneal cell photographing apparatus described above, when the subject is fixated on the fixation target at a required position around the standard fixation target and the corneal endothelium is photographed, the photographing can be performed with good precision. When recording both an anterior ocular segment image showing an imaging region and a magnified corneal endothelium image of a subject, it is desirable to eliminate the difference in image quality between the two. That is, when the imaging system is advanced while projecting the alignment index light onto the portion to be inspected and keeping the corneal reflected light point at a predetermined position on the image receiving surface of the television camera as the image receiving element, the observation distance changes due to the change in the observation distance. The anterior eye observation (photographing) optical system is a dark optical system because it is necessary to increase the depth of focus. However, an image for recording an anterior ocular segment image by the optical system and a fast movement due to fixation fine movement and the like. It is necessary to use a single image receiving element to receive an image for recording a magnified image of the corneal endothelium by an enlargement optical system using stroboscopic light of a corneal cell and two images having different brightness with good image quality.

For this reason, in the above-mentioned apparatus, a gain switching means is provided in the television camera 35, and the gain (sensitivity) of the television camera 35 is increased by the epithelium detection signal of the focus detection light-receiving element 18 so that the alignment light of the test site is adjusted. It is preferable to record the anterior segment image where the point is located, restore the gain (sensitivity) of the television camera 35 after the recording, and record an enlarged image of the corneal endothelium of the test portion using the endothelium detection signal. As a result, two images having different brightness between the anterior ocular segment image and the magnified corneal endothelium image can be received with good image quality by the television camera 35, and good images can be recorded by the recording means attached to the device. it can.

[0026]

The corneal thin film of the present invention according to claim 1 or 2.
According to the alveolar imaging apparatus, when the imaging area of the cornea of the subject's eye is switched and moved to perform imaging, the imaging direction is perpendicular to the corneal surface such as the corneal endothelial surface of the imaging region or the corneal epithelial surface to which a contact lens is attached. Thus, the imaging of the anterior segment of the eye where the light spot is located by the alignment index light can be performed, and the magnified image of the corneal cell of the target area can be accurately and satisfactorily captured.

[0027]

[Brief description of the drawings]

FIG. 1 is an optical path diagram of an embodiment of the present invention.

FIG. 2 is a front view of an anterior eye showing a cornea observation / photographing site.

FIG. 3 is a fixation target arrangement view corresponding to an observation / imaging region viewed from a subject.

FIG. 4 is a diagram showing an operation button for switching a fixation target.

FIG. 5 is a diagram showing the relationship between the imaging region, the alignment target light position, and the fixation direction during corneal center imaging.

FIG. 6 is a diagram illustrating a relationship between an imaging region, an alignment target light position, and a fixation direction during corneal peripheral imaging.

[Explanation of symbols]

1 ... eyeball 2 ... ocular surface (cornea) 3 ... imaging system 4 ... lighting lamp 8 ... strobe discharge tube 11 ... infrared reflecting and visible light transmitting mirror 12 ... illumination optical axis 13 ... projection lens 14 _1, 14 ₂ ... Enlarge Optical axis of photographing optical system 15 Objective lens 16 Infrared light transmitting / visible light reflecting mirror 18 Light receiving element for focus detection 20 Magnifying lens 21 Half mirror 22 Optical axis of photographing optical system of anterior eye part 23 Half mirror 24 visible light cut filter 25 anterior segment photographing lens 26 near infrared light emitting diode for alignment index 27 visible light emitting diode for central fixation target 27 ₁ visible light emitting diode for peripheral fixation target 33 infrared light emitting diode 34: CCD light receiving surface (image receiving surface) 35: TV camera 37: Change button 38: Center button 39: Record button A: Alignment index light A ': Alignment index light Reflected light AP, AP ': alignment index virtual image P: imaging direction Pc: imaging center S: fixation direction (line of sight) O: eye rotation point Q1: center of corneal epithelium Q2: center of corneal endothelium 2a: corneal epithelium 2b: corneal endothelium a , B, c, d, e ... corneal surface photographing site a ', b', c ', d', e '... fixation target (fixation lamp)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-146410 (JP, A) JP-A-58-200730 (JP, A) JP-A-5-3856 (JP, A) JP-A-63-1988 5726 (JP, A) JP-A-1-207703 (JP, A) JP-A-63-5724 (JP, A) JP-A-5-146410 (JP, A) JP-A-6-311968 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) A61B 3/135

Claims (2)

(57) [Claims] 1. An illumination optical system for slit-illuminating an eye spherical surface of an eye to be inspected, and an enlargement optical system for forming an enlarged image of a portion to be inspected on an image receiving surface of a television camera based on slit illumination light illuminating the eye spherical surface. System, at least a focusing detection light receiving element set at a position for receiving the corneal reflection light of the slit light via the objective lens, and an anterior eye part for photographing the anterior eye part based on anterior eye part illumination light A plurality of fixation targets including a photographing optical system, a central target which is set to face the subject's eye and is provided with a visible light source and is switchable, and an alignment indicator for projecting alignment target light toward the subject's eye A light projection unit, a corneal reflected light receiving unit that receives a corneal reflected light of the alignment index light, and a corneal reflected light of the alignment index by moving an imaging system with respect to the subject's eye according to an output from the light receiving unit. Means of light receiving element A corneal cell photographing apparatus, characterized in that the corneal cell photographing device comprises means for positioning the fixation target at a predetermined position on the light receiving element in response to the lighting movement of the fixation target. 2. The center of curvature of the corneal endothelium of the eye to be examined, whose line of sight is directed in the direction of the illuminated fixation target, corresponding to the lighting movement of the fixation target, It is characterized by moving a predetermined position on the light receiving element so as to be located on the optical axis, so that the imaging direction is orthogonal to the corneal endothelium surface at the imaging center of the anterior ocular segment imaging optical system. The corneal cell photographing apparatus according to claim 1.