JP3512822B2 - Photocoagulation equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocoagulator for observing a fundus of a fundus with a laser beam and for coagulating a desired part of the fundus with a therapeutic laser beam.

[0002]

2. Description of the Related Art Conventionally, there has been known a technique for performing photocoagulation of a fundus with a laser photocoagulation device having a configuration combined with a slit lamp microscope.

[0003]

In the conventional photocoagulation apparatus as described above, because of corneal reflection due to illumination light, etc.,
The field of view of the fundus that can be observed is almost slit-shaped and fairly narrow.

For this reason, it is difficult to quickly identify a diseased site obtained from a color fundus photograph or a wide-range photograph by fluorescence angiography, and it is necessary to move the visual field one after another according to the spread of the affected area. Yes, considerable skill and skill was required.

An object of the present invention is to solve the above problems.
Scanning with a high degree of freedom in the configuration of the optical system
Eye without changing the field of view with a laser ophthalmoscope
The bottom image to enlarge on a monitor, and at the same time the diseased site can be easily identified in clear fundus image, the color can indicate the location of the spot image of the treatment laser beam to overlap with the fundus image, Ahn
An object of the present invention is to provide a photocoagulator capable of performing all and efficient treatments.

[0006]

In order to solve the above-mentioned problems, the photocoagulation apparatus according to the present invention observes the fundus of the eye using a laser beam, and also uses a therapeutic laser beam to determine the desired part of the fundus. In a photocoagulation apparatus that performs photocoagulation, a laser beam for observation is two-dimensionally deflected and scanned to irradiate the fundus of an eye to be examined, and reflected light from the fundus is received by a predetermined light receiving element.
Optical means for obtaining a fundus image by performing light and photoelectric conversion, a therapeutic laser light source having a different wavelength from the observation laser light, and the observation laser light disposed behind the objective lens of the optical means. transmitted through a dichroic mirror for reflecting the treatment laser beam, the dichroic
In the optical path in the direction reflected by the ic mirror,
The light beam emitted from the medical laser light source is scanned onto the fundus.
A first lens arranged to form a pot image
System, and a spot image of the therapeutic laser beam on the fundus of the eye.
It is almost optically aligned with the iris of the eye to be moved to any position.
The scan mirror placed at the position of the hand and the dichroic
In the optical path in the direction reflected by the ic mirror,
To detect the spot image of the medical laser light on the fundus
In different directions separated from the optical path of the therapeutic laser light
And a second lens system arranged in the
A two-dimensional image pickup device formed on the fundus by a system,
The signal from the original image sensor is input and the light receiving element of the optical means is input.
Synthesized by superimposing on the signal from the child,
The position of the spot image is obtained by the light receiving element of the optical means.
Signal processing device for displaying the fundus image on the monitor screen
A configuration having a storage device is adopted.

[0007]

According to the above configuration, the therapeutic laser for photocoagulation treatment is used.
The spot image of the light is the optical path of the scanning laser ophthalmoscope .
Via a two-dimensional image sensor that is placed outside
Can be detected easily and the degree of freedom in the configuration of the optical system is great.
On the target screen is enlarged by the scanning laser ophthalmoscope
A therapeutic laser that is superimposed on a clear fundus image with a wide field of view
The position of the light is displayed in color, so the coagulation site can be clearly identified.
Therefore, it becomes possible to perform treatment safely and efficiently .

[0008]

EXAMPLES Examples will be described below with reference to the drawings. In the present embodiment, the fundus of the eye to be examined is irradiated with a laser beam, which is two-dimensionally deflected and scanned, and a scanning laser ophthalmoscope that receives the reflected light from the fundus and photoelectrically converts it to obtain a fundus image. A configuration in which a laser photocoagulator having a different wavelength from the observation laser beam is combined is used.

In FIG. 1, a laser beam 2 from an observation laser light source (for example, He-Ne laser) 1 is A.
By passing through an OD (acousto-optic deflecting element) 4, deflection scanning is performed in a one-dimensional direction (horizontal direction). Before and after the AOD, a beam is shaped and incident on the short aperture of the AOD,
Lenses 3 and 5 are arranged for obtaining the beam in the original shape after emission.

The laser beam scanned in the horizontal direction by the AOD passes through the lens 6, the slit 7 and the lens 8 and is guided to the mirror 9. The slit 7 is for blocking the 0th dimension of the AOD and passing only the temporarily diffracted light.

The scanning mirror 9 is attached to the galvanometer 10 and vibrates to cause AO of laser light.
Deflection scanning is performed in a direction (vertical direction) orthogonal to the deflection direction of D.

The laser beam two-dimensionally scanned by the scanning mirror 9 passes through the lens 11, is reflected by the small mirror 12, passes through the dichroic mirror 26, and is imaged on the fundus 14a of the subject's eye 14 by the objective lens 13. To do.

The scanning mirror 9 and the small mirror 12 are the lens 1
1, and the small mirror 12 and the iris (pupil) 14b are arranged substantially optically conjugate with respect to the objective lens 13.

Thus, the laser beam for observation always passes through the center of the pupil to scan the fundus.

Here, the dichroic mirror 26 has a property of transmitting the observation laser light and reflecting the therapeutic laser light. The reflected light from the fundus 14a of the subject's eye 14 spreads over the pupil and passes through the objective lens 13,
The light passes through the dichroic mirror 26, passes outside the small mirror 12, and is focused on the light receiving surface of the light receiving element 16 by the lens 14 ′ .

A filter 15 for transmitting only the laser light for observation is arranged in front of the light receiving element 16.

The amount of light received by the light receiving element 16 is converted into an electric signal, which is input to a signal processing device 17 constructed by using a computer system or the like, and processed into an image together with a laser beam scanning drive signal.

With the above structure, a clear fundus image is enlarged and displayed on the color monitor 18.

On the other hand, the therapeutic laser light source 21 uses, for example, an argon laser having a wavelength different from that of the observation light.
The light amount of this therapeutic laser light is reduced by the neutral density filter 22 and used for aiming at the photocoagulation position.

A fire button (not shown) during treatment
By giving a command by turning on, the neutral density filter 22 retracts from the optical path and increases the amount of light for treatment.

Further, the laser light passes through the telescope 23, and the scan mirror 24 and the dichroic mirror 2
It is reflected by 6 and is imaged on the fundus 14a of the subject's eye 14 by the objective lens 13. At this time, the telescope 23 moves the lens group in the optical axis direction to adjust the size of the spot size imaged on the fundus 14a as is known. The spot size conversion function is, for example, in the photocoagulation treatment of diabetic retinopathy (proliferation type), the spot size is 200 μm in the posterior pole part excluding the macula and its periphery, and 500 μm in the peripheral middle part, and the peripheral part Part is 500-1000 μm
To help you to treat efficiently. In addition, the spot on the exit end of the therapeutic laser beam is set to the objective lens 13
It also has a function of forming an image on the fundus 14a.

The scan mirror 24 is arranged at a position substantially optically conjugate with respect to the iris 14b and the objective lens 13. Further, the scan mirror 24 is connected to the micromanipulator 25 and the lever 25a is operated, whereby the therapeutic laser light always passes through the center of the pupil, and the therapeutic spot image can be moved to an arbitrary position on the fundus.

The therapeutic laser light reflected by the fundus spreads over the pupil, passes through the objective lens 13, is reflected by the dichroic mirror 26, and is scanned by the scan mirror 24.
The light is focused by the lens 27 and passes through the outside of the image forming an image on the light receiving surface of the image pickup device 29.

A protection filter 2 is provided in front of the image pickup device 29.
8 is arranged so as to protect the image pickup device from a strong therapeutic laser beam and to retract the therapeutic laser beam from the optical path when it is used for aiming.

That is, it is closely related to the attachment / detachment of the neutral density filter 22, and when the fire button is turned on, first, the protective filter 28 is inserted, and the neutral density filter 22 is retracted from the optical path to perform photocoagulation. The protection filter 28 withdraws from the optical path after the restoration.

The detection information of the position of the spot image by the image pickup device 29 is input to the signal processing device 19, synthesized so as to be superposed on the fundus image by the scanning laser ophthalmoscope, and enlarged and displayed in color on the monitor 18. At this time, it is more convenient for the color of the spot image displayed in color to be of the same type as the color of the therapeutic laser light.

Specifically, the fundus (retina) is composed of several layers such as the retinal surface layer, retinal nerve fiber layer, retinal pigment epithelium layer, choroid, etc. Laser light is selected according to the condition to be treated. In the case of the present invention, when a He-Ne laser (wavelength 633 nm) is used as an observation laser light source, argon blue (488n) having a wavelength sufficiently different from that of the He-Ne laser is used as a therapeutic laser light.
m), argon green (514 nm), DYE yellow (577 nm), DYE orange (590n)
It is possible to incorporate m) or the like for selective use. At this time, the spot image position and size on the monitor
The wavelength of the selected laser light is also displayed in the same system color for convenience of operation.

[0028] In the above-described configuration, even when treatment with photocoagulation, fundus images photocoagulation position and its state it is possible to visually recognize by always color monitor without loss, fundus image by scanning laser ophthalmoscope With a wide field of view equivalent to that of the field of view, this field of view can be expanded to a monitor without changing the field of view frequently, and a diseased site can be easily identified with a clear fundus image. It can be displayed in color by overlapping with, and treatment can be performed efficiently.

[0029]

As is apparent from the above description, according to the present invention, an optical system that does not use a pinhole or the like in the detection system is used.
Adopting a scanning laser ophthalmoscope with a great degree of freedom in the configuration
The optical system is easy to adjust and the optical system can be constructed at a relatively low cost.
And a clear fundus image with a wide field of view is constantly monitored.
Features of the scanning laser ophthalmoscope that can be enlarged and displayed on the surface
Spot image of therapeutic laser light that can be spotted
Is placed out of the optical path of the scanning laser ophthalmoscope.
Can be detected at any time via the two-dimensional image sensor
Display on the video signal from the laser ophthalmoscope
As a result, the photocoagulation position and its state can be accurately measured in real time without the fundus image disappearing even during treatment with photocoagulation.
It is possible to visually recognize the monitor screen, cheap
It is possible to provide an excellent photocoagulation device capable of performing all and efficient treatment.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a photocoagulation device adopting the present invention.

[Explanation of symbols]

1 Laser light source for observation 2 laser beam 3,5,6,8,11,27 lens 4 AOD (acousto-optic deflection element) 9 Scanning mirror 10 Galvanometer 12 small mirrors 13 Objective lens 14 eye 14a fundus 14b Iris (pupil) 15 filters 16 Light receiving element 17 Signal processing device 18 color monitor 21 therapeutic laser light source 22 Dark filter 23 Telescope 24 scan mirror 25 Micro Manipulator 26 dichroic mirror 28 Protection filter 29 Image sensor

Front Page Continuation (72) Inventor Koji Nakanishi, 3-14-14 Nihonbashihonmachi, Chuo-ku, Tokyo Kowa Co., Ltd., Electrical Optical Division (56) Reference JP-A-2-161944 (JP, A) JP-A-2 −271820 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) A61F 9/007 A61B 3/10 A61B 18/20

Claims (4)

(57) [Claims] 1. A photocoagulation apparatus for observing a fundus with a laser beam and photocoagulating a desired part of the fundus with a therapeutic laser beam, wherein the observation laser beam is two-dimensionally deflected and scanned. It irradiates the fundus of the eye to be inspected, and the reflected light from the fundus of the eye is received by the specified light receiving element
Optical means for receiving and photoelectrically converting the fundus image to obtain a fundus image, a therapeutic laser light source having a different wavelength from the observation laser light, and the observation laser light disposed behind the objective lens of the optical means. To the dichroic mirror that transmits the therapeutic laser light and the optical path in the direction reflected by the dichroic mirror.
And a light beam emitted from the therapeutic laser light source
Is placed to form a spot image on the fundus.
A first lens system and a spot for the therapeutic laser light.
Iris and light of the subject's eye that moves the image to any position on the fundus
In the optical path in the direction reflected by the dichroic mirror and the scan mirror located at a position that is almost conjugate to each other.
The spot image of the therapeutic laser light on the fundus.
Separated from the optical path of the therapeutic laser light for detection
A second lens system arranged in a different direction, and
Two-dimensional image pickup device focused on the fundus by the second lens system
And a signal from the two-dimensional image sensor,
The signal from the light receiving element of
The position of the spot image of the laser light on the light receiving element of the optical means.
The signal that is displayed on the monitor screen of the obtained fundus image
Photocoagulation apparatus characterized by having a No. processor. 2. A He--Ne laser for observation,
The photocoagulation apparatus according to claim 1, wherein an argon laser is arranged for treatment. 3. The therapeutic laser wherein the first lens system is
ー Different size of the light beam emitted from the light source on the fundus
Spot size change for forming a spot image of
It has a conversion function, The claim 1 of Claim 2 characterized by the above-mentioned.
The photocoagulation device according to claim 1. 4. A signal processing device comprising the two-dimensional image pickup device
Input the signal from the light receiving element of the optical means
The position of the spot image of the therapeutic laser light is superimposed and synthesized.
Of the fundus image obtained by the light receiving element of the optical means.
Depending on the wavelength of the therapeutic laser light on the monitor screen
Color display is carried out, Claim 1-Claim 3
The photocoagulation device according to claim 1.