JP3630805B2 - Ophthalmic diagnostic equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ophthalmologic diagnosis apparatus that observes the fundus of a subject's eye and irradiates light on the fundus to measure the characteristics of the subject's eye.
[0002]
[Prior art]
Examples of an ophthalmologic diagnosis apparatus that measures the characteristics of an eye to be inspected by irradiating a laser into the eye include a fundus blood flow meter and a laser flare cell meter. Fundus blood flow meters measure the blood flow of the fundus blood vessels that can be directly observed non-invasively. Various fundus blood flow meters using the Doppler measurement principle or speckle phenomenon by irradiating laser light have been devised. A wide range of future applications are expected.
[0003]
[Problems to be solved by the invention]
In the ophthalmologic diagnosis apparatus as described above, MPE (Maximum Permissible Exposure) that is the maximum allowable laser energy that can be irradiated is defined by ANSI (AMERICA NATUALAL STANDARDDS INSTITUTE) for the safety of the eye of the subject.
[0004]
However, the above-described conventional ophthalmologic diagnosis apparatus is troublesome because the examiner himself measures the irradiation time of the measurement laser beam on the eye fundus to be examined and irradiates it so as not to exceed the MPE.
[0005]
An object of the present invention is to provide an ophthalmologic diagnosis apparatus that can solve the above-described problems and can irradiate measurement light with energy that does not exceed MPE easily and more reliably.
[0006]
[Means for Solving the Problems]
To achieve the above object, an ophthalmologic diagnosis apparatus according to the present invention includes input means for inputting subject information for specifying a subject , irradiation means for irradiating measurement fundus on the fundus of the subject eye , A time measuring means for measuring the irradiation time of the measurement light; and an integrating means for calculating an irradiation energy of the measurement light that reaches the eye to be examined based on an integrated value of the output of the measurement light at the irradiation time ; Storage means for storing the irradiation energy in association with the subject, calculation means for calculating the total value of the irradiation energy to the eye, and display means for displaying the total value for each subject. Features.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
FIG. 1 is an external view of the embodiment, which is composed of a measuring head 2, a television monitor 3, and a chin support 4 that can be moved back and forth and right and left on the stage unit 1. A knob 6, a numeric keypad 7 for inputting a subject ID number, an irradiation laser energy display LED 8, a switch 9, a blood flow rate display LED 10, and a subject list display liquid crystal display 11 are provided. 12, a focus knob 13 is provided.
[0008]
A fundus blood flow meter main body having the configuration shown in FIG. 2 is built in the measuring head 2, and yellow-green is present on the optical path from the illumination light source 21 made of a tungsten lamp or the like that emits white light to the objective lens 22. An image rotator 32 connected to a band pass filter 23 that transmits only the luminous flux in the region, a condenser lens 24, a mirror 25, a field lens 26, a ring lens 27, relay lenses 28 and 29, a perforated mirror 30, and a positioner 31 is disposed. ing.
[0009]
In addition, small mirror pairs 33a and 33b, lenses 34a and 34b, and photomultipliers 35a and 35b are disposed on the optical path extending in two directions upward from the opening of the perforated mirror 30, respectively. In FIG. 2, only members on the optical axis of the small mirror 33a are shown to avoid duplication. The outputs of the photomultipliers 35a and 35b are connected to the blood flow rate calculation unit 36, and the blood flow rate calculation unit 36 is connected to the blood flow rate display LED 10.
[0010]
On the optical path behind the perforated mirror 30, an aperture 37 conjugate with the pupil and an image stabilizer 38 are arranged. In the image stabilizer 38, lenses 39 and 40, a galvanometric mirror 41, lenses 42 and 43, a galvanometric mirror are arranged. 44, and the galvanometric mirrors 41 and 44 are rotatable by the operating rod 12. The galvanometric mirror 41 has a rotation axis perpendicular to the paper surface, and the galvanometric mirror 44 is orthogonal to the rotation axis. A rotation axis B is provided in the drawing. Further, the galvanometric mirror 41 is connected to the output of the control means 46.
[0011]
On the optical path behind the galvanometric mirror 44, a focusing lens 47, a lens 48, a dichroic mirror 49, a lens 50, a half mirror 51, a switchable ND filter 52, 53, and a measurement laser are movable along the optical axis. A light source 54 is arranged. On the optical path in the reflection direction of the dichroic mirror 49, a half mirror 55, a chart 56, a lens 57, an image rotator 59 driven by a controller 58 connected to the positioner 31, a lens 60, and a TV camera 61 are arranged. The output of the camera 61 is connected to the television monitor 3 and an observation optical system 62 is configured.
[0012]
On the optical path in the reflection direction of the half mirror 55, a mirror 63, a lens 64, a filter 65, and a CCD array sensor 66 with an image intensifier are arranged to constitute a blood vessel detection system 67.
[0013]
The output of the CCD array sensor 66 is connected to a blood vessel image analysis circuit 68 composed of a tuning memory circuit, a memory processing circuit, a control unit, etc., and the output of the blood vessel image analysis circuit 68 is connected to a control means 46 for driving a galvanometric mirror. Has been.
[0014]
A photodiode 69 is disposed on the optical path in the reflection direction of the half mirror 51, and the output of the photodiode 69 is connected to the system controller 70. In addition, the system controller 70 is connected to the switch 9, the subject ID number input numeric keypad 7, the irradiation laser energy display LED 8, the subject list display liquid crystal display 11, the laser driving circuit 71, the timer 72, and the memory 73. Then, output signals S1 and S2 to be supplied to the blood flow velocity calculation unit 36 and the blood vessel image analysis circuit 68 are generated. The output of the laser drive circuit 71 is connected to the measurement laser light source 54.
[0015]
Further, the ring image PR, the small mirror images Ma and Mb, and the aperture image PA, which are the images of the ring slit 27, the small mirror pairs 33a and 33b, and the aperture 37, with respect to the pupil of the eye E are shown in FIG. It has become.
[0016]
When performing measurement, first, a list of subjects stored in the memory 73 is displayed on the subject list display liquid crystal display 11, and the examiner refers to the list as necessary, and the subject ID number is displayed. The subject ID number is input from the input numeric keypad 7. Then, the system controller 70 refers to the memory 73 and displays the irradiation energy irradiated to the subject on that day on the irradiation laser energy display LED 8. Next, the examiner fixes the subject's face to the chin support 4 and observes the fundus.
[0017]
The illumination light beam from the illumination light source 21 is imaged on the openings of the bandpass filter 23, the condenser lens 24, the mirror 25, the field lens 26, and the ring slit 27, and once formed on the apertured mirror 30 by the relay lenses 28 and 29. After that, the image passes through the image rotator 32 and the objective lens 22, and is imaged as a ring image R on the pupil of the eye E to illuminate the fundus oculi Ea substantially uniformly.
[0018]
Reflected light at the fundus oculi Ea is extracted from the aperture image PA at the pupil and returns through the same optical path, passes through the aperture of the perforated mirror 30, the aperture 37, and the lenses 39 and 40 of the image stabilizer 38, the galvanometric mirror 41, and the lens 42. 43, galvanometric mirror 44, further passing through focusing lens 47 and lens 48, reflected by dichroic mirror 49, and passing through half mirror 55, chart 56 of observation optical system 62, lens 57, image rotator 59, and lens 60. The fundus image Ea ′ is formed on the TV camera 61 and displayed on the TV monitor 3. The examiner performs alignment of the apparatus and selection of a measurement site while observing the television monitor 3.
[0019]
Note that the light beam reflected by the half mirror 55 passes through the mirror 63, the lens 64, and the filter 65 of the blood vessel detection system 67, and is enlarged from the fundus image Ea ′ captured by the TV camera 61 by the CCD array sensor 66. It is received as an image Ev ′. The output signal from the CCD array sensor 66 is processed by the blood vessel image analysis circuit 68 into various data such as the blood vessel position and width, the movement amount of the blood vessel Ev being measured, the contrast between the blood vessel Ev and the retina, and the movement of the blood vessel Ev. Data representing the quantity is transmitted to the control means 46.
[0020]
When performing alignment, the operation rod 5 and the operation knob 6 are operated to slide the stage unit 1 in the XZ plane and in the Y direction, thereby aligning the apparatus with respect to the eye E. Next, the focus knob 13 adjusts the focus of the fundus image Ea ′ so that the fundus image Ea ′ including a desired measurement site is displayed on the television monitor 3. After the alignment is completed, the examiner presses the switch 9 to turn on the measurement laser light source 54 and select a measurement site.
[0021]
In this embodiment, a helium neon laser having a wavelength of 633 nm and an output of 5 mW is used as the measurement laser light source 54. The ND filters 52 and 53 can be selected by a lever (not shown). When the standard ND filter 52 is selected, the output of the laser light applied to the eye is 20 μW, and the ND filter 53 for high output is selected. When selected, it becomes about 100 μW. The system controller 70 calls out the total irradiation laser energy of the subject from the memory 73 and activates the timer 72, accumulates the irradiation laser energy from the output of the photodiode 69 and the output of the timer 72, and stores it in the memory 73. The value is displayed on the irradiation laser energy display LED 8.
[0022]
In this embodiment, the ratio between the integrated value of the irradiation laser energy and the MPE value stored in the memory 73 is taken and displayed. In this embodiment, the irradiation laser energy display LEDs 8 are arranged so that five LEDs are adjacent to each other, and as the ratio increases, the number of lights up increases. When the ratio exceeds 80%, the LED 8 blinks. When the MPE is exceeded, the laser drive circuit 71 is activated and the measurement laser light source 54 is turned off. In this example, the MPE is 12.8 mJ.
[0023]
The output of the photodiode 69 corresponds to the laser output applied to the subject's eye in advance. In this embodiment, the measurement laser light source 54 is extinguished when the MPE is exceeded, but a warning may be given by blinking an LED, a buzzer, or the like.
[0024]
The light beam from the measurement laser light source 54 passes through the lens 50, the dichroic mirror 49, and the focusing lens 47, and passes through the galvanometric mirror 44, the lenses 42 and 43, the galvanometric mirror 41, and the lenses 40 and 39 of the image stabilizer 38, and the aperture. 37, a perforated mirror 30, an image rotator 32, and the objective lens 22, an aperture image PA is formed on the pupil and projected onto the fundus oculi Ea of the eye E to be examined. The reflected light beam at the fundus oculi Ea returns on the same optical path, and a part thereof is reflected in two directions by the small mirror pair 33a, 33b.
[0025]
When the examiner presses the switch 9 again, output signals S1 and S2 are generated from the system controller 70, and the blood flow velocity calculation unit 36 and the blood vessel image analysis circuit 68 are activated to start measurement. The light beams reflected by the small mirror pairs 33a and 33b are light beams extracted from the mirror images Ma and Mb on the pupil, and form images on the photomultipliers 35a and 35b through the lenses 34a and 34b, respectively. In the blood flow velocity calculation unit 36, the received light signal is subjected to frequency analysis using the Doppler measurement principle, and the obtained blood flow velocity is displayed on the blood flow velocity display LED 10.
[0026]
On the other hand, the light beam that is not reflected by the pair of small mirrors 33a and 33b is a light beam that is extracted from the aperture image PA on the pupil and passes through the aperture of the perforated mirror 30, the aperture 37, the image stabilizer 38, the focusing lens 47, and the lens 48. The image is reflected by the dichroic mirror 49, passes through the half mirror 55, the chart 56, the lens 57, the image rotator 59, and the lens 60, and is imaged as a spot image PS by the television camera 61. 'Is projected with
[0027]
The reflected light beam at the fundus oculi Ea from the measurement laser light source 54 enters the blood vessel detection system 67 through the half mirror 55. However, since the filter 65 blocks the wavelength of the measurement laser light source 54, the CCD array sensor 66 Only the blood vessel image Ev ′ from the illumination light source 21 can be captured.
[0028]
The measurement laser light is imaged on a focal plane f conjugate with the fundus oculi Ea of the eye E of the lens 50, and the conjugate relationship is adjusted by the lenses 48 and 50. Therefore, when the examiner operates the focus knob 13 to perform alignment, the focusing lens 47 is moved along the optical axis, and the imaging surface of the television camera 61, the imaging surface of the CCD array sensor 66, and the focal plane of the lens 50 are moved. At the same time, f becomes conjugate with the fundus oculi Ea, and the fundus image Ea ′ is focused and the spot image PS is focused.
[0029]
At this time, the fundus oculi image Ea ′ is projected on the television monitor 3 as shown in FIG. The spot image PS is fixed at the center of the visual field, and the measurement site is selected by matching the spot image PS with a predetermined measurement site, rotating the image rotator 32, and setting the blood vessel image Ev ′ to be measured as the axis A. Axis. The direction of the coordinate axis A indicates a plane that connects the centers of the small mirror pairs 53a and 53b and the fundus oculi Ea.
[0030]
In this embodiment, instead of rotating the fundus image Ea ′ on the television monitor 3, the axis A is rotated. A straight line chart 56 including an intersection with the optical axis is arranged on a surface conjugate with the fundus oculi Ea of the eye E to be examined in front of the controller 58 of the observation optical system 62, and a chart image S is displayed on the television camera 61. Is imaged. The straight line of the chart 56 is parallel to the axis A and is adjusted in advance in the direction perpendicular to the arrangement direction of the elements of the CCD array sensor 66.
[0031]
When the image rotator 32 is rotated, the rotation amount of the image rotator 32 is converted into an electrical signal in the positioner 31 and transmitted to the controller 58. Under the control of the controller 58, the image rotator 59 is rotated by the same amount in the opposite direction to the rotation of the image rotator 32. Accordingly, the fundus image Ea ′ formed on the imaging surface of the television camera 61 is not affected by the rotation of the image rotator 32 and thus does not rotate. Therefore, the fundus image Ea ′ is not rotated on the television monitor 3 and the chart image S is not rotated. Rotate.
[0032]
While observing the television monitor 3, the examiner may operate the operation rod 12 of the measurement head 2 so that the direction of the blood vessel Ev at the measurement site and the chart image S coincide with each other. −Y direction) and the vertical and horizontal directions of the fundus image Ea ′ projected on the television monitor 3 always coincide.
[0033]
In this embodiment, the laser output is monitored by the photodiode 69. However, as another embodiment, when the laser output fluctuation is small, the laser output may be used as a predetermined value to calculate the irradiation energy. Even when the laser output is switched by switching the ND filter or changing the voltage as in this embodiment, a predetermined laser output value corresponding to the state can be used for the calculation of the irradiation energy.
[0034]
Furthermore, in this embodiment, the examiner first inputs the subject ID number from the numeric keypad 7 for inputting the subject ID number, but resets the subject ID number without inputting the subject ID number. It is also possible to continue calculating the irradiation energy up to.
[0035]
In this embodiment, one helium neon laser is used. However, when a plurality of laser beams having the same wavelength or a plurality of laser beams having different wavelengths are used, the laser beam is irradiated to each eye. What is necessary is just to calculate the sum of irradiation energy.
[0036]
In particular, since safety is important for laser light, an ophthalmic apparatus using laser light is given as an example in the present invention, but the same can be implemented for general incoherent light instead of laser light. It is. Further, as an example, a fundus blood flow meter in which the present invention is particularly effective is taken as an example, but the present invention is not limited to this.
[0037]
【The invention's effect】
As described above, the ophthalmologic diagnosis apparatus according to the present invention calculates the irradiation energy by integrating the output of the measurement light, and easily and more reliably irradiates the measurement light that does not exceed the MPE. And the safety of the subject can be ensured.
[0038]
Further, by providing an output measuring means for measuring the output of the measurement light, the irradiation energy can be accurately calculated even when the output is changed or the laser output fluctuates.
[0039]
Furthermore, by having the energy display means for displaying the irradiation energy, the examiner can know the irradiation energy, which helps to ensure the safety of the subject. Further, if the ratio between the irradiation energy and the predetermined value is displayed, the irradiation energy can be grasped more easily.
[0040]
If a warning is issued when the irradiation energy exceeds a predetermined value, it is possible to prevent the examiner from irradiating the measurement light beyond the MPE without noticing, and for the measurement based on the comparison result with the predetermined value. If the light irradiation is controlled, the examiner does not have to perform a troublesome operation of lowering or stopping the output of the measurement light based on the irradiation energy value.
[0041]
Further, if a storage means for storing the total daily irradiation energy for each subject is provided, even when intermittent measurement is performed on a single subject, the examiner can examine the subject. There is no need to calculate the sum of the irradiation energy for the day.
[Brief description of the drawings]
FIG. 1 is an external view of an embodiment.
FIG. 2 is a configuration diagram inside a measurement head.
FIG. 3 is an explanatory diagram of an arrangement relationship of each image of a ring slit, a small mirror pair, and an aperture on an eye pupil to be examined.
FIG. 4 is an explanatory diagram of a fundus image on a television monitor.
[Explanation of symbols]
3 TV monitor 5 and 12 Operation pole 7 Numeric keypad 8 for inputting patient ID number LED for laser energy display
10 Blood flow rate display LED
11 Subject List Display Liquid Crystal Display 21 Illumination Light Source 32, 59 Image Rotator 36 Blood Flow Rate Calculation Unit 38 Image Stabilizer 52, 53 ND Filter 61 Television Camera 62 Observation Optical System 54 Measurement Laser Light Source 67 Blood Vessel Detection System 68 Blood Vessel Image Analysis circuit 70 System controller

Claims (10)

Input means for inputting subject information for specifying the subject, irradiating means for irradiating a measuring light onto the fundus of the eye, and time measuring means for measuring the irradiation time of the measuring light, the Integration means for calculating the irradiation energy of the measurement light that reaches the eye to be examined based on the integrated value of the output of the measurement light at the irradiation time; storage means for storing the irradiation energy in association with the subject; An ophthalmologic diagnosis apparatus comprising: a calculation unit that calculates a total value of irradiation energy to the eye to be examined; and a display unit that displays the total value for each subject . The ophthalmic diagnostic apparatus according to claim 1, wherein the measurement light is laser light. The ophthalmologic diagnosis apparatus according to claim 1, further comprising a light receiving unit configured to receive a reflected light flux of the measurement light on the fundus and measuring a blood flow state of the fundus based on a signal from the light receiving unit. The output of the measurement light is associated with the output of the irradiation unit, and the integration unit calculates the irradiation energy from the integrated value of the output of the irradiation unit in the irradiation time. The ophthalmic diagnostic apparatus according to Item . The ophthalmologic diagnosis apparatus according to any one of claims 1 to 4, wherein the display unit displays a total value of the irradiation energy by a ratio with a predetermined value . Comparing means for comparing the total value of the irradiation energy with a predetermined value, ophthalmic diagnostic apparatus according to any one of claims 1-5 and a warning means for warning based on the comparison result. Ophthalmic diagnostic according to the comparison means and any one of claims 1-5 and a control means for controlling said irradiating means based on the comparison result of comparing the total value of the irradiation energy with a predetermined value apparatus. The ophthalmologic diagnosis apparatus according to claim 7 , wherein the control unit performs control so that the eye to be examined is not irradiated with the measurement light. The ophthalmologic diagnosis apparatus according to claim 1, wherein the identification of the subject is performed by presenting a list of subjects. The ophthalmologic diagnosis apparatus according to claim 1, wherein the display unit displays the total value when an input is made to the input unit.

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