JP4267339B2 - Corneal endothelial cell imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a corneal endothelial cell imaging apparatus that images corneal endothelial cells of a subject's eye.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, a corneal endothelial cell imaging apparatus described in Patent Document 1 is known as an apparatus capable of imaging corneal endothelial cells without contact with an eye to be examined. In the corneal endothelial cell image photographed by this type of ophthalmic apparatus, a spotted black portion may be seen on the photographed image. This phenomenon is also found in Non-Patent Document 1, as shown in Non-Patent Document 1. )is called.
[0003]
[Patent Document 1]
JP-A-5-146410
[Non-Patent Document 1]
Hikaru Kanno, 2 others, “Changes in corneal endothelial cells immediately after wearing soft contact lenses”, Journal of Japanese Contact Lens Society, 1993, Vol. 35, No. 2, p. 140-145
[0004]
[Problems to be solved by the invention]
The above bleb occurs when the subject has a low oxygen partial pressure, such as when using a contact lens with low oxygen permeability, and the cornea is released from the hypoxic state by removing the contact lens. It is known to recover quickly. In addition, it has been found that there are individual differences in the appearance of blebs, and the observation results of such changes may be used in screening and the like as an index representing the constitution of individuals in the future.
[0005]
However, while it is not yet clear what the bleb is actually, the bleb is only observed as a black shade in the conventional corneal endothelial cell imaging device as described above. Therefore, it is desirable that the corneal endothelial cell imaging apparatus has a function for capturing the bleb from various angles.
[0006]
The present invention has been made in view of the above circumstances, and has as its object to provide a corneal endothelial cell imaging apparatus that has an optical system for capturing a bleb from various angles and can be used for elucidation of the substance. Yes.
[0008]
[Means for Solving the Problems]
  Claim 1The present invention relates to an illumination optical system that irradiates illumination light to the eye to be examined, and imaging optics that captures the corneal endothelial cell by receiving reflected light of the illumination light by the corneal endothelial cell of the eye to be examined by an imaging means. A phase plate and a polarizing plate are provided in order from the eye side in each of the illumination optical system and the photographing optical system, and the polarizing plate provided in the photographing optical system is rotatable about the optical axis. In addition, the imaging device is characterized in that the imaging means receives reflected light from the corneal endothelial cells through the polarizing plate.
[0010]
  Claim 2The invention according toClaim 1The corneal endothelial cell imaging apparatus according to claim 1, further comprising a focus position correction unit that corrects a focus position of the imaging unit.
[0011]
  Claim 3The invention according toClaim 1 or claim 2In the corneal endothelial cell photographing apparatus described in (2), the photographing optical system is capable of photographing a moving image by the photographing means.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0013]
  FIG. 1 shows a schematic configuration of a corneal endothelial cell imaging apparatus.The corneal endothelial cell imaging apparatus 100 includes an anterior ocular segment observation optical system 1, an index projection optical system 10, an XY alignment detection system 20, and an imaging unit inside an apparatus main body 101 that can move in three axial directions of XYZ. The illumination optical system 30, the Z alignment detection illumination optical system 40, the photographing optical system 50, the Z alignment detection system 60, and a control circuit 70 are included.
[0014]
The anterior ocular segment observation optical system 1 is arranged on the left and right sides of the eye E, and a plurality of infrared illumination light sources 2 that directly illuminate the anterior ocular segment, a half mirror 3, an objective lens 4, and a half mirror 5, a CCD camera 6 capable of shooting a moving image, and a light shielding plate 7. The reflected light from the anterior segment of the eye E is guided to the CCD camera 6 through the half mirror 3, the objective lens 4 and the half mirror 5, and an anterior segment image is formed on the imaging surface of the CCD camera 6. The CCD camera 6 outputs an image signal to a monitor device (not shown), and an anterior eye image 9 is displayed on the screen 8 of the monitor device as shown in FIG. The light shielding plate 7 is retracted from the optical path of the anterior ocular segment observation optical system 1 during anterior ocular segment observation, and is inserted into the optical path during corneal endothelial cell imaging described later.
[0015]
The index projection optical system 10 includes a light source 11 that emits infrared light, a condenser lens 12, an aperture stop 13, a pinhole plate 14, a dichroic mirror 15, and a projection lens 16. The aperture stop 13 is provided at a position conjugate with the apex P of the cornea C of the eye E with respect to the projection lens 16. The pinhole plate 14 forms an alignment index, and the focal point of the projection lens 16 coincides with the location of the pinhole plate 14. The dichroic mirror 15 and the projection lens 16 together with the half mirror 3 constitute a fixation target projection optical system 17, and the fixation target projection optical system 17 further includes a fixation light source 18 that emits visible light and a pinhole plate 19. The pinhole plate 19 is disposed at the focal position of the projection lens 16, and the fixation target light emitted from the fixation light source 18 passes through the pinhole plate 19 and the dichroic mirror 15 and is then converted into a parallel light beam by the projection lens 16. Then, it is reflected by the half mirror 3 and guided to the eye E to be examined. When the subject gazes at the fixation target light, the line of sight of the subject (eye E) is fixed.
[0016]
Infrared light emitted from the light source 11 is condensed by the condenser lens 12, passes through the aperture stop 13, and is guided to the pinhole plate 14. The light beam that has passed through the pinhole plate 14 is reflected by the dichroic mirror 15 and guided to the projection lens 16. The projection lens 16 converts the light beam that has passed through the pinhole plate 14 into a parallel light beam, which is reflected by the half mirror 3 and projected onto the cornea C as index light for detecting the alignment in the XY directions. As shown in FIG. 3, the index light projected onto the cornea C is formed on the surface T of the cornea C so as to form a bright spot image R at an intermediate position MP between the apex P of the cornea C and the center of curvature MR of the cornea C. Reflected.
[0017]
The reflected light from the cornea C is guided to the objective lens 4 after passing through the half mirror 3. The half mirror 3 and the objective lens 4 constitute an XY alignment detection system 20 together with the half mirror 5, and the XY alignment detection system 20 further includes an image receiving element 21 made of PSD and an XY alignment detection circuit 22. A part of the index light condensed by the objective lens 4 is reflected by the half mirror 5 and guided to the image receiving element 21, and the bright spot image R 1 corresponding to the bright spot image R is the image receiving surface of the image receiving element 21. Formed. The image receiving element 21 outputs a signal relating to the formation position of the bright spot image R <b> 1 to the XY alignment detection circuit 22, and the output of the XY alignment detection circuit 22 is input to the control circuit 70. On the other hand, the index light transmitted through the half mirror 5 is guided to the CCD camera 6, and a bright spot image R <b> 2 is formed on the imaging surface of the CCD camera 6. In FIG. 2, the bright spot image corresponding to the bright spot image R2 is represented by reference numeral R2 '. In FIG. 2, reference numeral 23 denotes a mark indicating an allowable alignment range generated by an image generation unit (not shown), and the apparatus main body 101 is driven by an examiner so that the bright spot image R <b> 2 ′ enters the mark 23. Is done.
[0018]
The photographing illumination optical system 30 includes a photographing illumination light source 31, a condenser lens 32, a slit plate 33, a dichroic mirror 34, an aperture stop 35, and an objective lens 36. For example, a xenon lamp is used as the photographing illumination light source 31. The dichroic mirror 34 has a transmission characteristic of transmitting visible light and reflecting infrared light, and the aperture stop 35 is provided at a position conjugate with the cornea C with respect to the objective lens 36. The dichroic mirror 34, the aperture stop 35, and the objective lens 36 constitute a Z alignment detection illumination optical system 40. The Z alignment detection illumination optical system 40 further includes a light source 41 that emits infrared light, a condenser lens 42, And a slit plate 43.
[0019]
Visible light as illumination light emitted from the photographing illumination light source 31 is condensed by the condenser lens 32 and guided to the slit plate 33, and the visible light passing through the slit plate 33 passes through the dichroic mirror 34 as slit light. The light is transmitted and guided to the aperture stop 35, and the cornea C is illuminated from the oblique direction by the objective lens 36. The infrared light emitted from the light source 41 passes through the slit plate 43 while being focused by the condenser lens 42, becomes slit light, is reflected by the dichroic mirror 34, is guided to the aperture pattern 35, and the aperture stop 35. After being transmitted, it is guided to the cornea C while being focused by the objective lens 36.
[0020]
The imaging optical system 50 receives the reflected light from the endothelial cells of the cornea C of the eye E from an oblique direction substantially symmetrical to the imaging illumination optical system 30 with respect to the optical axis O of the eye E, and the corneal endothelial cells of the eye E Shoot. The photographing optical system 50 includes an objective lens 51, a dichroic mirror 52, a mask 53, a mirror 54, a relay lens 55, a moving mechanism 75, a polarizing filter 80, a light shielding plate 56, a mirror 57, and a CCD. And a camera 6. The dichroic mirror 52 has a transmission characteristic of transmitting visible light and reflecting infrared light. The moving mechanism 75 is a known lens moving mechanism, and moves the relay lens 55 in the optical axis direction. The mirror 57 is disposed at a position that does not hinder the anterior ocular segment observation light beam, and is inclined at the same angle as the inclination angle θ on the object side (the eye E side). The objective lens 51 and the dichroic mirror 52 constitute a Z alignment detection system 60. The Z alignment detection system 60 further includes a linear sensor 61 and a Z alignment detection circuit 64. The linear sensor 61 is conjugated with the cornea C with respect to the objective lens 51. It is provided at a position.
[0021]
The reflected light from the cornea C of the slit light projected by the Z alignment detection illumination optical system 40 is reflected by the dichroic mirror 52 while being focused by the objective lens 51 and is imaged on the linear sensor 61. The linear sensor 61 detects the light intensity distribution of the reflected light, and FIG. 4 shows an example of the light amount distribution on the linear sensor 61. When the surface of the cornea C is smooth, the peak portion 62 of the light beam reflected by the surface T of the cornea C and the peak portion 63 of the light beam reflected by the corneal endothelial cell surface N described below are shown in FIG. It appears clearly. The detection result of the linear sensor 61 is output to the Z alignment detection circuit 64, and the output of the Z alignment detection circuit 64 is input to the control circuit 70.
[0022]
Further, as shown in FIG. 5, the slit light beam L irradiated by the photographing illumination optical system 30 is reflected by the cornea C. Specifically, a part of the slit light beam L is at the boundary surface between the air and the cornea C. A part of the light beam reflected at a certain corneal surface T and transmitted through the corneal surface T is reflected at the corneal endothelial cell surface N. Of the light beams included in the reflected light of the cornea C, the reflected light beam T ′ from the corneal surface T has the largest amount of light, and the reflected light beam N ′ from the corneal endothelial cell surface N has a relatively small amount of light. The amount of the reflected light beam M ′ is the smallest. The reflected light from the cornea C passes through the dichroic mirror 52 while being collected by the objective lens 51, and is once imaged on the mask 53. Further, the reflected light beams T ′ and M ′ that do not form a corneal endothelial cell image are shielded by the mask 53, while the reflected light beam N ′ that has passed through the mask 53 is reflected by the mirror 54 and focused by the relay lens 55 while being polarized. The light passes through 80 and is guided to the mirror 57.
[0023]
The polarizing filter 80 has a property of transmitting only linearly polarized light in one direction, and can be rotated around the optical axis by a rotating mechanism 81. As the rotation mechanism 81, a mechanism capable of detecting a rotation angle such as a motor provided with an encoder or a stepping motor is used. The light transmitted through the polarizing filter 80 is reflected by the mirror 57 to form a corneal endothelial cell image on the CCD camera 6. On the screen 8 of the monitor device, as shown in FIG. A corneal endothelial cell image 58 is displayed. At this time, the moving mechanism 75 moves the relay lens 55 between the mask 53 as the first image forming point and the CCD camera 6 according to the rotation angle and type of the polarizing filter 80, thereby The focus can be corrected.
[0024]
When photographing the eye E with the corneal endothelial cell photographing apparatus 100, the examiner first operates a switch (not shown) to turn on the power. Then, since the control circuit 70 turns on the infrared illumination light source 2, the fixation light source 18, and the light sources 11 and 41 that emit infrared light, the examiner moves the apparatus main body 101 while viewing the screen 8 of the monitor apparatus, Approximate alignment is performed so that the anterior segment image 9 is positioned at the center of the screen. At this time, since the output of the XY alignment detection circuit 22 and the output of the Z alignment detection circuit 64 are input to the control circuit 70, the control circuit 70 monitors the relative position of the apparatus main body 101 with respect to the eye E to be examined. When the bright spot image R2 ′ enters the mark 23 and a light quantity distribution as shown in FIG. 4 is obtained, the control circuit 70 drives the apparatus main body 101 by a drive mechanism (not shown) to thereby display the apparatus main body 101. The alignment with respect to the eye E is automatically adjusted. In this automatic alignment, the XY alignment detection circuit 22 determines that the vertical / left / right positional relationship of the apparatus main body 101 with respect to the eye E is within an allowable range, and an XY alignment completion signal is transmitted to the control circuit 70, and the Z alignment detection is performed. When the circuit 64 determines that the distance in the optical axis direction of the apparatus main body 101 with respect to the eye E to be examined is within the allowable range and transmits a Z alignment completion signal to the control circuit 70, the process is completed. The Z alignment completion signal is transmitted to the control circuit 70 when, for example, the address Z of the peak portion 63 exists within the range of Δ on both sides of the reference address Q of the linear sensor 61 as the center.
[0025]
When the auto-alignment is completed, the control circuit 70 turns off the light sources 2, 11, 18, and 41, automatically causes the imaging illumination light source 31 to emit light, and executes imaging of a corneal endothelial cell image. Here, since the photographing optical system 50 is provided with a polarizing filter 80 that can rotate about the optical axis, the CCD camera 6 can photograph corneal endothelial cells through the polarizing filter 80. That is, the corneal endothelial cell image to be photographed changes depending on the properties of the cornea and the wavelength characteristic of the apparatus. Here, the corneal endothelial cell can be photographed by extracting an arbitrary linearly polarized component by rotating the polarizing filter 80. Therefore, it is possible to obtain a photographed image useful for observation of a bleb different from that of a conventional corneal endothelial cell photographing apparatus.
[0026]
In this embodiment, since imaging is performed particularly using polarized light, phase changes in corneal cells and anterior aqueous humor can be observed. The CCD camera 6 not only performs still image shooting with a flash as in a conventional corneal endothelial cell imaging apparatus, but also shoots moving images of corneal endothelial cell images (for example, intermittent moving image shooting every predetermined time or polarizing filter 80). (Moving image shooting while rotating the lens) can also be performed, so that continuous observation of a bleb whose shape changes in a relatively short time is also possible. Furthermore, by correcting the focus of the CCD camera 6 by the moving mechanism 75, astigmatism of the polarizing filter 80 is suppressed, and a better captured image can be obtained.
[0027]
Note that the control circuit 70 may perform shooting not only when the polarizing filter 80 is at a specific rotation position but also by sequentially rotating the polarizing filter 80 by the rotation mechanism 81. What is necessary is just to repeat the rotation of the filter 80, the auto alignment of the apparatus main body 101, and the imaging | photography procedure. The polarizing filter 80 may be manually rotated. In such a case, it is desirable to provide a rotation angle detection mechanism such as an encoder and record the detected rotation angle in the captured image. Alternatively, a polarization angle input device that receives an input of a polarization angle by an examiner may be provided, and the polarization filter 80 may be automatically or manually rotated based on the input, and a predetermined or arbitrary rotation angle may be set. A storage mode for storing may be provided, and the polarizing filter 80 may be rotated stepwise (for example, in 45 ° steps) based on the stored information in the storage mode to perform intermittent shooting.
[0028]
  Embodiment1]
  FIG. 7 shows a schematic configuration of the corneal endothelial cell imaging apparatus according to the present embodiment. In this corneal endothelial cell imaging device 102, a λ / 4 plate and a polarizing filter are provided in order from the eye E side in each of the imaging illumination optical system 30 and the imaging optical system 50, and the polarizing filter 80 and the rotation mechanism 81 are provided. Is not providedAlthough different from the corneal endothelial cell imaging apparatus 1 shown in FIG.Since the others are the same, the same reference numerals are given and the description is omitted.
[0029]
The λ / 4 plate 76 is provided across the photographing illumination optical system 30 and the photographing optical system 50. The polarization filter 77 is provided immediately before the λ / 4 plate 76 in the optical path of the photographic illumination optical system 30, and the polarization filter 78 is provided immediately after the λ / 4 plate 76 in the optical path of the imaging optical system 50. Is provided so as to be rotatable. The linearly polarized light that has passed through the polarizing filter 77 in the photographic illumination optical system 30 passes through the λ / 4 plate 76 to become circularly polarized light and is reflected by the eye E, and then passes again through the λ / 4 plate 76 to be linearly polarized light. And passes through the polarizing filter 78. When this polarizing filter 78 acts in the same manner as the polarizing filter 80 in the first embodiment, the CCD camera 6 can take an image useful for observing a bleb different from the conventional corneal endothelial cell photographing apparatus. Further, the incident light beam to the eye E is changed to circularly polarized light by the λ / 4 plate 76, and the phase of only the surface reflection of the cornea C is shifted by π, so that when the polarization axes of the polarizing filters 77 and 78 are equal, the eye E It is possible to eliminate the influence of surface reflection on the surface.
[0030]
By the way, in the photographing optical system 50, since the polarizing filter 78 transmits only a certain linearly polarized light, the light quantity of the optical system after that changes due to the rotation of the polarizing filter 78. Since this change in the amount of light also occurs in the Z alignment optical system 60 sharing the optical system, for example, the change in the amount of light due to the rotation angle of the polarizing filter 78 is examined in advance, and the control circuit 70 determines the light source according to the change in the amount of light. By changing the light quantity 41 or the sensitivity of the linear sensor 61, it is possible to reduce the influence of the change in the light quantity accompanying the rotation of the polarization filter 78 on the alignment detection in the Z direction.
[0031]
In this embodiment, one λ / 4 plate extends over the photographing illumination optical system 30 and the photographing optical system 50. However, a λ / 4 plate may be disposed in each optical system.
[0032]
  FIG. 8 is partially different from the corneal endothelial cell imaging apparatus shown in FIG.1 shows a schematic configuration of a corneal endothelial cell imaging apparatus. The corneal endothelial cell imaging device 103 includes a color filter 82 and an insertion / removal mechanism 83 instead of the polarizing filter 80 and the rotation mechanism 81.Corneal endothelial cell imaging apparatus 1 shown in FIG.Since they are the same as those in FIG.
[0033]
The color filter 82 exhibits, for example, blue, yellow, or green, and is inserted into and removed from the optical path of the imaging optical system 50 by the insertion / removal mechanism 83. The control circuit 70 is connected to the eye E with the color filter 82 inserted into the optical path. Perform imaging of corneal endothelial cells. Although only one color filter 82 is shown in FIG. 7, for example, a plurality of color filters may be prepared, and they may be inserted / removed in accordance with the wavelength of the illumination light, etc. The color filter 82 may be inserted / removed manually by the examiner instead of automatically by the insertion / removal mechanism 83. Further, the color filter 82 may be disposed in the photographic illumination optical system 30 instead of being disposed in the photographic optical system 50, but at this time, the light source 31 rather than the dichroic mirror 34 intersecting with the Z alignment detection illumination optical system 40. By arranging so that the conjugate condition of the illumination optical system 30 is not broken, the influence of the color filter 82 on the Z alignment detection illumination optical system 40 can be avoided.
[0034]
  thisAs shown in FIG.In the corneal endothelial cell photographing apparatus 103, the CCD camera 6 can photograph corneal endothelial cells through the color filter 82, so that a photographed image reflecting the properties of the cornea and the wavelength characteristics of the apparatus can be obtained as in the first embodiment. In addition, it is possible to improve the contrast of the captured image by the amount that the wavelength is limited. Further, the moving mechanism 75 moves the relay lens 55 according to the type of the color filter 82 and corrects the focus of the CCD camera 6, thereby suppressing the chromatic aberration of the color filter 82 and obtaining a better captured image. it can.
[0035]
  more thanDescribed corneal endothelial cell imaging deviceIn FIG. 1, the corneal endothelial cell image was photographed with the CCD camera 6, but this photographed image may be recorded only when the alignment of the apparatus main body 101 with respect to the eye E is completed, or the examiner Only the necessary video may be recorded by the above operation, and the recording capacity of the image can be suppressed. The recording time of the photographed video may be arbitrarily set by the examiner, and a preset mode in which observation conditions assumed in advance are stored may be prepared in order to simplify photographing and improve operability, or A memory mode may be prepared for the examiner to store observation conditions. For example, when the polarization filter 80 is rotated little by little and the bleb is observed well, the rotation angle (rotation position) of the polarization filter 80 at that time is stored in a memory (not shown) in the control circuit 70 together with the still image. The shooting operation can be facilitated by storing (using the memory mode) and calling the stored rotation angle at the next shooting.
[0036]
Instead of moving the relay lens 55 by the moving mechanism 75, the objective lens 51 and the CCD camera 6 may be moved based on the rotation angle of the polarizing filter 80 and the type of the polarizing filter 80 or the color filter 82 ( A piezo element or the like can be used to move the CCD camera 6). However, since the former movement affects the XY alignment detection system 20 and the latter movement affects the Z alignment detection system 60, it is necessary to take measures such as moving the light receiving element 21 and the linear sensor 61 or adding a lens. It becomes.
[0037]
In addition, for a plurality of captured images of the same eye with different polarization angles of the polarizing filter 80, types of the polarizing filter 80 or the color filter 82, moving image shooting elapsed time, etc., alignment and brightness correction are performed by a known image processing method. It is possible to extract the image change by performing the difference process.
[0038]
  In addition,The corneal endothelial cell imaging deviceThen, when obtaining XY alignment, parallel light is projected onto the eye E to detect the position of the reflected image of the cornea C, and when obtaining Z alignment, slit light is projected onto the eye E from an oblique direction to linearly. Although the position of the reflected light on the sensor 61 is detected, other known methods may be employed.
[0039]
  Embodiment2]
  As described above, it is known that the bleb appears in a low oxygen state (it is said to be 2000 Pa (15 mmHg) or less), and it is necessary to keep the state where the oxygen partial pressure is lowered for several tens of minutes. . In addition to the method of wearing a contact lens with low oxygen permeability, the specific method of causing the bleb to appear is to keep wearing the contact lens to ensure the appearance of the bleb while reducing the influence of oxygen permeability of the contact lens. There is a way to close it. However, even in this case, the subject must be closed for several tens of minutes, so the burden is large, and when the oxygen partial pressure rises due to opening, the bleb disappears in a relatively short time Therefore, it is desirable if a low oxygen state can be maintained without placing a burden on the subject as much as possible. In this embodiment, a corneal oxygen partial pressure reducing apparatus 84 shown in FIG. 9 will be described as an apparatus therefor.
[0040]
The corneal oxygen partial pressure reducing device 84 includes goggles 85, a gas generator 86, and a gas humidifier 87. The goggles 85 are provided around the goggles main bodies 88 and 88 covering the examinee's eye and the goggles main bodies 88 and 88 so as to be in close contact with the examinee's eyes and seal the inside of the goggles main bodies 88 and 88. The seal portions 89 and 89 to be kept in contact with each other, the connecting portion 90 positioned at the nasal root of the subject by connecting the goggles main bodies 88 and 88, and the inside and outside of the goggles main bodies 88 and 88 through the seal portions 89 and 89. Gas inflow pipes 91, 91 and gas exhaust pipes 92, 92, open / close valves 93, 93 for opening and closing the pipes of the gas inflow pipes 91, 91, and open / close valves 94 for opening / closing the pipes of the gas exhaust pipes 92, 92 , 94 and a belt 95 for fixing the goggles 85 to the head of the subject.
[0041]
The windows 88a and 88a in front of the goggles main body 88 and 88 are made of a simple transparent material and do not have any positive or negative power, and are formed so as to be substantially parallel to the subject's eye when the goggles 85 are worn. Therefore, the transmitted light does not have an optical influence as much as possible. As the gas inflow pipe 91 and the gas exhaust pipe 92, rubber tubes having good sealing properties and flexibility are used.
[0042]
The gas generator 86 is filled with nitrogen, and the gas humidifier 87 is constituted by a water tank stored inside, and both are connected by a connecting pipe 96 whose flow rate is adjusted by an on-off valve 98. Further, the gas humidifier 87 and the gas inflow pipe 91 of the goggles 85 are connected by a connecting pipe 97, and here, the connecting pipe 96 and the connecting pipe 97 are also rubber tubes.
[0043]
In order to image the eye E with the corneal endothelial cell imaging device 100 using the corneal oxygen partial pressure reducing device 84, the subject wears goggles 85 and the jaw of the corneal endothelial cell imaging device 100 (not shown). Put your chin on the receiver and prepare for shooting. In this state, the window portion 88a of the goggle main body 88 functions as a photographing window so that the photographing illumination optical system 30 and the photographing optical system 50 are substantially perpendicular to the anterior ocular segment observation optical system 1. It is inserted into each optical system so as to overlap substantially symmetrically. Accordingly, it is preferable that the window portion 88a is made of a member that is as thin as possible so as not to cause distortion in order to reduce the change in the optical path length. Further, if the window portion 88a is too close to the eye E, the influence of reflected light is large. Since it is easily soiled by tears and tears, it is preferable that the eye E is separated from the eye E within a range where there is no inconvenience in the wearing feeling and the working distance with respect to the eye E.
[0044]
When this preparation is completed, the examiner causes nitrogen to flow out from the gas generator 86 and sends it into the goggle bodies 88 and 88. Specifically, nitrogen from the gas generator 86 is released into the water of the gas humidifier 87 through the connection pipe 96 and is humidified here, and then the inside of the goggle main body 88 through the connection pipe 97 and the gas inflow pipe 91. The amount of gas sent into the goggle main body 88 is controlled according to the opening degree of the on-off valve 93 and the on-off valve 94. Nitrogen inside the goggle main body 88 is exhausted from the gas exhaust pipe 92 in such a manner that it is pushed out by new nitrogen that flows in sequentially. At this time, by putting the discharge side end of the gas discharge pipe 92 in the liquid, the examiner can easily grasp the outflow state of the gas, and pressure is applied to the gas discharge pipe 92 and the gas inflow pipe 91. A meter may be provided to observe changes in gas flow.
[0045]
Subsequently, the control circuit 70 executes XY alignment and Z alignment. Since it is considered that the reflected light of the goggles 85 affects these executions, the corneal endothelial cell imaging device 100 is provided with a manual imaging mode, By providing a function for automatically expanding the allowable alignment range based on the elapsed time from the start of the alignment, it becomes easier to perform photographing. From the viewpoint of suppressing the influence of reflected light on the XY alignment detection system 20, the normal direction of the window 88a of the goggle main body 88 is slightly inclined with respect to the optical axis of the anterior ocular segment observation optical system 1, It is also effective to give the window 88a a curvature.
[0046]
When the oxygen partial pressure inside the goggle body 88 is sufficiently lowered and the alignment of the apparatus body 101 with the eye E is completed, the corneal endothelium is maintained while the humidified nitrogen flows into the goggle body 88 in a substantially constant state. Take a picture of the cells. At the time of this imaging, the eye E is maintained in a low oxygen state by the corneal oxygen partial pressure reducing device 84, so that the eye E is in a stable state over the imaging period, and the bleb that has appeared once disappears easily. In addition, since the subject is ready for photographing only by wearing the goggles 85, the burden is reduced.
[0047]
In the above, humidified nitrogen was used to reduce the partial pressure of oxygen because it is the main component of air and has little effect on the human body, but other gases other than oxygen may be used if there is little effect on the human body. Absent. In addition, the gas is sent into the goggles main body 88 after the preparation for photographing is completed. However, the preparation for photographing may be performed after a while has passed since the gas was sent into the goggles main body 88 in advance. The window 88a and the other part (the part 88b around the window 88a) of the goggle main body 88 may be integrally formed as long as the above-mentioned conditions are satisfied. The on-off valve for controlling the air pressure inside the goggle main body 88 may be provided at another location. Furthermore, by making the goggles 85 separable from the other while keeping the inside of the goggles main body 88 sealed, the subject can easily move and the burden is reduced.
[0048]
Note that the corneal oxygen partial pressure lowering device does not necessarily have to take the form of goggles. For example, the corneal oxygen partial pressure reducing device may be a helmet that entirely covers the subject's head, or an oxygen supply device for breathing. It may be a low oxygen partial pressure chamber provided.
[0049]
【The invention's effect】
Since the corneal endothelial cell imaging apparatus according to the present invention is configured as described above, it has an optical system for capturing the bleb from various angles, and has been capable of imaging a corneal endothelial cell image that has been impossible until now. It can be performed, and it has the effect that it can be used for elucidation of the substance of the bleb.
[Brief description of the drawings]
[Figure 1]Corneal endothelial cell imaging device2A is a side view thereof, and FIG. 2B is a plan view thereof.
FIG. 2 is an explanatory diagram showing an anterior segment image displayed on the screen of the monitor device.
FIG. 3 is an explanatory diagram showing a projection state of alignment target light onto the cornea.
FIG. 4 is an explanatory diagram showing a light amount distribution state of slit light on a line sensor.
FIG. 5 is an explanatory diagram showing a projection state of slit light onto the cornea.
FIG. 6 is an explanatory diagram showing a corneal endothelial cell image displayed on the screen of the monitor device.
FIG. 7 shows an embodiment.1Pertaining toCorneal endothelial cell imaging device2A is a side view thereof, and FIG. 2B is a plan view thereof.
[Fig. 8]Corneal endothelial cell imaging apparatus different from the corneal endothelial cell imaging apparatus shown in FIG.2A is a side view thereof, and FIG. 2B is a plan view thereof.
FIG. 9 shows an embodiment.2It is explanatory drawing which shows the corneal oxygen partial pressure lowering apparatus used by 1.
[Explanation of symbols]
6 CCD camera (photographing means)
30. Illumination optical system for photography (illumination optical system)
50 Shooting optical system
75 Movement mechanism (focus position correction means)
77 λ / 4 plate (phase plate)
78 Polarizing filter (polarizing plate)
80 Polarizing filter
82 color filter
100 Corneal endothelial cell imaging device
102 Corneal endothelial cell imaging device
103 Corneal Endothelial Cell Imaging Device
C cornea
E Eye to be examined

Claims (3)

An illumination optical system for irradiating illumination light to the eye to be examined, and an imaging optical system for photographing the corneal endothelial cells by receiving reflected light of the illumination light by the corneal endothelial cells of the eye to be examined by an imaging means The illumination optical system and the imaging optical system are each provided with a phase plate and a polarizing plate in order from the eye side, and the polarizing plate provided in the imaging optical system is rotatable about the optical axis. Corneal endothelial cell imaging means, wherein the imaging means receives reflected light from the corneal endothelial cells through a polarizing plate . The corneal endothelial cell imaging means according to claim 1, further comprising a focus position correcting means for correcting a focus position of the imaging means. The corneal endothelial cell photographing means according to claim 1 or 2, wherein the photographing optical system is capable of photographing a moving image by the photographing means.

Images