JPH042248B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an attachment for constructing a specular microscope for observing and/or photographing corneal endothelial cells.

On the back surface of the cornea of the human eye, there are hexagonal cells called corneal endothelial cells, which are approximately 20 μm in size and play an important role in maintaining the transparency of the cornea. In recent years, with the development and spread of surgical microscopes and the like, eye surgery techniques have become more sophisticated, and for example, vitreous surgery, ultrasonic cataract surgery, corneal transplant surgery, artificial lens transplant surgery, etc. are becoming commonplace. For this reason, the contact of surgical instruments with the surgical eye and the influence of intraocular irrigation fluids such as physiological saline and Ringer's solution on the corneal endothelial membrane can lead to decreased visual acuity due to decreased corneal transparency after surgery. Therefore, it is important to observe and/or photograph corneal endothelial cells as they are in the living body, and to measure and examine changes therein.

As a device for observing and photographing corneal endothelial cells, a device called a specular microscope has been developed and put into practical use. As shown in Figure 1, the specular microscope has the following features:
The illumination light flux S is transmitted from the slit illumination optical system to the cornea C.
A slit image A appears on the corneal endothelial cell layer EC.
image. The illumination light flux S is the corneal endothelial cell layer.
It is specularly reflected by EC and emitted outside the eye as a reflected light beam L. It is configured so that an image of the corneal endothelial membrane by this reflected light beam L is observed and photographed.

In general, the cornea is a translucent body, and the reflectance of the corneal endothelial cell layer is extremely low. Therefore, as mentioned above, a specular microscope uses specular reflection light from the corneal endothelial cell layer to observe and photograph endothelial cells. It is configured as follows. Therefore, the slit illumination optical axis OS and the optical axis OL of the reflected light beam are configured to have a mutually symmetrical angle α with respect to the normal O of the illumination member (ie, the observation site).

However, the reflectance of the upper surface of the cornea is much higher than that of the corneal endothelial cell layer (the reflectance of the corneal endothelial cell layer is approximately 0.02% of the amount of irradiated light).
Since the reflectance of the upper surface of the cornea is approximately 2.5%) and the thickness of the cornea is extremely thin, the retroreflective light flux R from the upper surface of the cornea enters the observation field of the specular microscope. As a result, in the observed or captured image, as shown in Figure 2, the corneal endothelial cell image IEC and the corneal scattered light flux image IC are partially overlapped by the reflected image IR due to the light reflected from the upper surface of the cornea, and the corneal endothelial cell image IEC and the corneal scattered light flux image IC are partially overlapped. The major drawback was that it had a negative impact on observation.

In addition, the conventional specular microscope was a single-function, dedicated machine that could only be used for observing and photographing corneal endothelial cells, but the present applicant previously proposed that ophthalmology We have proposed a slit lamp device that can also be used as a specular microscope by simply replacing the objective lens of the observation microscope section of the slit lamp device, which is more common and essential for many people, with a specular attachment. This dual-purpose specular microscope is characterized in that it uses a slit illumination section of a slit lamp to illuminate corneal endothelial cells. For this purpose, as shown in Fig. 1, it is necessary to position the optical axis OL of the observation microscope section and the optical axis OS of the slit illumination section so that they form the same angle with respect to the normal O of the member to be observed. Another drawback is that it is difficult to perform an alignment operation in which the specularly reflected light flux from the endothelial cells is incident on the observation microscope and aligned within the field of view of the microscope.

In addition, a specular microscope is used to determine whether corneal endothelial cells have undergone degeneration due to surgery, etc., by counting the number of endothelial cells per unit area, the size of individual cells, and the state of size variation. Placing scale lines inside the observation microscope,
Further, the photographing device is configured so that the scale lines are imprinted on the endothelial cells at the same time. Conventional scale lines are formed by vapor-depositing aluminum on a glass plate, and because they appear as black lines within the observation field, they are difficult to see in the weak endothelial cell observation image, and when taking photographs, they are difficult to see in the endothelial cell image. This had disadvantages such as having to imprint the image, which interfered with the painstakingly recorded photographic image.

The present invention was made in order to solve the drawbacks of the conventional specular microscope, and its first purpose is to reduce harmful reflected light from the upper surface of the cornea so as to more sharply observe corneal endothelial cells. An object of the present invention is to provide an attachment that can be attached to a general slit lamp or the like in order to configure a specular microscope that can take pictures.

A second object of the present invention is to provide an attachment for constructing a specular microscope in which the alignment operation for aligning the corneal endothelial cell observation site within the field of view of the observation optical system is extremely simple.

Furthermore, the third object of the present invention is to make the reference scale for obtaining a unit area field for counting the number of corneal endothelial cells easier to see and to obtain images of corneal endothelial cells compared to conventional specular microscopes. An object of the present invention is to provide an attachment for configuring a specular microscope that can observe and/or record without overlapping.

The first feature of the structure of the present invention to achieve the above object is that it has an objective lens that once images the range reflected light from the corneal endothelial cells onto an intermediate image point, and this intermediate image point A diaphragm having a diaphragm aperture and a narrow slit aperture on the outer edge of the diaphragm aperture is arranged, and when light reflected from the upper surface of the cornea passes through the slit aperture, light reflected from the corneal endothelial cells can pass through the diaphragm aperture. The diaphragm aperture and the slit aperture are formed in such a manner that they are related to each other. With this configuration, when the reflected light reaches the slit opening position from the upper surface of the cornea, the reflected light from the corneal endothelial cells automatically passes through the diaphragm opening, which not only makes alignment very easy, but also allows the slit opening to Because it is thin, most of the harmful reflected light from the upper surface of the cornea is blocked by the aperture plate, so it does not interfere with observation and photography of corneal endothelial cells.

Furthermore, if a plurality of slit openings are formed along the diaphragm opening at predetermined intervals, the slit openings allow the reflected light from the upper surface of the cornea to pass through, so that they can be used as a scale, and the scale line has the characteristic that it does not overlap with the corneal endothelial cell image formed through the aperture.

Embodiments of the present invention will be described below with reference to the drawings.
The first embodiment was previously filed by the applicant in Japanese Patent Application No. 54-18711.
This is a combination of a photo-slit lamp with a binocular observation microscope section for enumerating cell parts such as the cornea, which was proposed in the above issue. As shown in FIG. 3, the observation microscope section 101 of the photo slit lamp is an optical system consisting of a variable magnification lens system 11, a beam splitter 12, an imaging lens 13, an erecting prism 14, a focus plate 15, and an eyepiece lens 16. A pair of systems are arranged symmetrically. A typical photo-slit lamp like this has two variable magnification lens systems for binocular observation.
1, and an objective lens large enough to cover the two variable magnification lens systems 11 is placed in front of these variable magnification lens systems 11, and the light beam passing through this one objective lens is divided into two variable magnification lenses. It is configured to be guided to the lens system 11. Observation microscope section 101 shown in FIG.
This shows the state with the other objective lens removed.

The attachment housing 100 includes an objective lens 10
2. It has an optical system consisting of a reflecting prism 103, a diaphragm plate 104, and a relay lens 105.

The attachment housing 100 has an engaging portion 107 for attaching to the observation microscope section 101 of the photo-slit lamp, and the engaging section 107 is attached to the attachment position of the objective lens of the observation microscope section 101. The attachment housing 100 allows the corneal endothelium to be observed by emitting a light beam from the corneal endothelial cells through one optical system of the observation microscope section 101.

When this attachment housing 100 is attached to a slit lamp and used as a specular microscope, corneal endothelial cells are slit-illuminated by a slit illumination means that can be rotated to the left and right of the slit lamp.

As shown in FIG. 3, the illumination optical system for slit illumination includes a lamp 4, a condenser lens 5,
A slit aperture 6 and a photographic lens 7 are arranged coaxially. The image of the slit aperture 6 is projected by a projection lens 7 onto the endothelial cell layer of the cornea C of the eye to be examined.

The configuration of the aperture plate 104 is as shown in FIG.
A wide and vertically long aperture aperture 31 and this aperture aperture 31
It is composed of a narrow slit opening 32a formed perpendicular to the longitudinal direction of the slit. This diaphragm plate 104 is placed at the intermediate imaging point 30 of the corneal endothelial cells by the objective lens 102 .

Next, the function and usage of this device will be explained. First, the line of sight of the eye to be examined is fixed by having the examinee fixate the fixation target 1 . Next, the illumination lamp 4 of the illumination optical system is turned on to illuminate the eye to be examined with the slit light. The examiner moves the device holding means up and down, left and right, and back and forth, so that the strong reflected light from the upper surface of the cornea hits the aperture plate 1.
The light is roughly aligned so that the light enters between the diaphragm apertures 31 of 04. Subsequently, by slightly moving the device left and right, it is moved to a position where the strong reflected light R from the upper surface of the cornea leaks out slightly through the slit opening 32a. As a result, only the reflected light beam L from the corneal endothelial cells passes through the diaphragm aperture 31. On the other hand, most of the reflected light R from the upper surface of the cornea is
This will be blocked by the aperture plate 104. By slightly moving the device back and forth in this state, the corneal endothelial cell image can be focused and observed, and can be recorded on the film 19 if necessary.

In this way, according to the present embodiment, strong reflected light from the upper surface of the cornea, which was conventionally considered to be harmful light, is actively utilized. That is, when the reflected light from the upper surface of the cornea enters the position of the slit opening 32, an intermediate image of the originally required reflected light from the corneal endothelial cells can be formed at the aperture position, and the alignment is extremely improved. Not only is it easy to make, but the slit opening is extremely narrow, so it can block most of the harmful reflected light from the upper surface of the cornea. Therefore, this embodiment has the advantage that corneal endothelial cells can be observed and photographed more clearly than the conventional specular microscope.

The second embodiment of the present invention, as shown in FIG.
By forming a large number of slit openings in the aperture plate of the first embodiment at equal intervals, the slit openings can be used as scale lines. The aperture plate 50 has a narrow slit opening 5.
11a, 512a, 513a, . . . 51na are formed at equal intervals at predetermined intervals. These slit openings 51na (n = 1, 2...n) are illuminated by light reflected from the upper surface of the cornea, so the examiner can observe them as if they were scale lines lined up at equal intervals, and they can also be photographed on photographic film. This makes it very convenient for counting corneal endothelial cells.

Furthermore, since a slit opening is formed on the side of the diaphragm opening 52 of the diaphragm plate 50 where an intermediate image of the corneal endothelial cells is formed, the scale line never overlaps the corneal endothelial cell image due to the slit opening. There isn't. Therefore, observation and counting are easy;
Further, information on corneal endothelial cells is not partially erased.

Since the slit illumination means is located on both the right and left sides of the observation microscope section, slit openings 1101, 1102...110n are formed on the right side of the aperture plate 104, as shown in FIGS. 4 and 5. If the slit illumination means is placed on either side, it can be used.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing the relationship between light incident on the cornea and reflected light, Figure 2 is a diagram showing an image of corneal endothelial cells obtained with a conventional specular microscope, and Figure 3 is an explanatory diagram showing the relationship between light incident on the cornea and reflected light.
The figure is an optical layout diagram showing the first embodiment of the present invention, and FIG. 4 is a plan view showing the configuration of the aperture plate of the first embodiment.
FIG. 5 is a plan view showing the configuration of a diaphragm plate according to a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Fixation target, 6...Slit aperture, 10...Relay lens, 12...Beam splitter, 30...Intermediate image point, 31...Aperture aperture, 100...Attachment housing, 101... …
Observation microscope section, 104...Aperture plate, 105...Relay lens, C...Cornea of the eye to be examined.

Claims (1)

[Scope of Claims] 1. An objective lens of the observation optical means of a slit lamp device having a slit illumination optical means for illuminating the eye to be examined with a slit light beam, and an observation optical means for observing the illumination part of the eye to be examined; A device which is replaced and attached to the observation optical means, and which relays an objective lens for corneal endothelial cell observation and an intermediate point image formed by the corneal endothelial cell observation objective lens to the observation optical means. In an attachment device for constructing a specular microscope having a relay lens for emitting light, an aperture plate for controlling light reflected from the upper surface of the cornea is disposed at the intermediate imaging point position, and An attachment device for constructing a specular microscope, characterized in that the aperture plate is formed with an aperture aperture and at least one alignment aperture disposed at the outer edge of the aperture aperture. 2 The alignment openings are at least two slit-shaped openings formed in a direction perpendicular to the longitudinal direction of the diaphragm opening, and the intervals between the slit openings are a predetermined constant interval. 2. The attachment device according to claim 1, wherein the attachment device has a scale and can be used as a scale.