JPH0434893B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a measurement system that measures the cornea of an eye to be examined without contact, such as a corneal refractive power measuring means, and
The present invention relates to an ophthalmologic apparatus that combines a measurement system such as an ultrasonic axial length measurement means that measures the eye by contacting the subject's eye.

[Conventional technology]

Conventionally, in cataract surgery, in which the cloudy crystalline lens is extracted and an artificial crystalline lens is inserted, when selecting an artificial crystalline lens with an appropriate refractive power, the corneal refractive power is measured using an optical measuring device, and then the corneal refractive power is measured using an optical measuring device. A commonly used method is to determine the length of the artificial lens using an ultrasonic axial length measuring device, and calculate the refractive power of the artificial lens from both values using a predetermined calculation formula.

[Problem that the invention is trying to solve]

However, in the past, corneal refractive power and axial length were measured using separate devices, which required fixing the patient's face on the face holder of the device and aligning the sliding table before measuring. There is a problem in that the operation has to be performed separately for each device, making measurement cumbersome and time-consuming. Furthermore, not only is a large installation space required, but there are also other problems, such as the need to move patients with poor eyesight.

Therefore, there is a desire to combine the functions of measuring corneal refractive power and axial length in one device, but it is not easy to operate the switch for each purpose, and if the switch is operated incorrectly, it may cause damage to other objects. There was a problem that there was a risk that the data could be mixed up with the optometry data, and that there was a risk of making an error in the IOL calculation of the eye to be examined.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention includes a first measurement system that detects first eye information while maintaining a predetermined distance from the eye to be examined, and a detection terminal in contact with the eye to be examined. and a second measurement system for detecting second eye information on the eye to be examined in the same measuring instrument body, the ophthalmologic apparatus is capable of switching between the first and second measurement systems while the position of the eye to be examined is fixed. , a determining means for determining whether the state is the measurement result of the first measurement system or the second measurement system;
It is characterized by comprising means for switching between the first and second measuring systems in accordance with the output of the determining means.

〔Example〕

The present invention will be explained in detail based on illustrated embodiments.

In FIG. 1, a first measuring system for measuring the corneal refractive power of the eye E to be examined and a second measuring system for determining the ocular axial length are installed in the main body 2 provided on the sliding table 1. It is being In the first measurement system, an objective lens 3 is arranged facing the eye E, and mirrors 4, 5, an imaging lens 6,
A two-dimensional image sensor 7 consisting of a CCD or the like is arranged,
The output of this two-dimensional image sensor 7 is connected to a television monitor 8. The objective lens 3 and mirrors 4 and 5 are integrally constructed and can be moved up and down by a wire 10 driven by an electric motor 9. Further, around the objective lens 3, as shown in FIG. 2, a plurality of projection target light sources 11a to 11d made of light emitting diodes and the like are arranged at equal intervals with the optical axis L as the center.

Further, in the second measurement system, an ultrasound probe 12 placed behind the mirror 4 is held by a sliding guide member 14 via a probe holder 13,
This ultrasonic probe 12 is urged forward by a tension spring 15. Further, the ultrasonic holder 13 can be moved back and forth by a wire 17 that is moved by an electric motor 16. In addition, in FIG. 1, 18 and 19 are wires 10 and 17, respectively.
20a is the operation stick, 20 is a guide roller that guides the
b indicates a vertical movement adjustment ring. Further, 31 is an advance switch that gives execution instructions for each measurement.

Here, when the projection target light sources 11a to 11d are projected onto the cornea of the eye E to be examined with a predetermined spatial distance,
The projection optotype light source 11a~ by the convex mirror action of the cornea.
The corneal reflection image 11d is formed,
Since the mutual relationship between the light spot positions of these corneal reflection images changes depending on the radius of curvature of the cornea and the degree of astigmatism, by detecting this change, it is possible to determine the corneal refractive power, degree of corneal astigmatism, and axial angle. It is well known that it is possible to obtain

On the other hand, the ultrasound probe 12 is connected to the cornea Ec of the eye E to be examined.
The axial length from the surface of the cornea Ec to the retina is determined by emitting ultrasonic pulses from the tip of the probe 12 and receiving reflected echoes from the retina of the eye E. It is also well known that it is possible to detect and obtain measured values.

Here, the first measurement system is the projection target light source 11a~
The corneal reflection image of 11d is transmitted to the objective lens 3, the mirror 4,
5. Detection is performed by forming an image on a two-dimensional image sensor 7 using an optical system consisting of an imaging lens 6.

This detection signal is subjected to video freeze processing and the like in a video signal processing circuit 32 shown in FIG. 3, and a calculation circuit 30 determines corneal refractive power, corneal astigmatism, and axial angle.

Further, in the second measurement system, the motors 9 and 16 are driven and controlled so that the objective lens 3 and mirrors 4 and 5 are lowered and the probe 12 is slid in the direction of the eye E to be examined. Next, the ultrasonic reflection signal obtained when the probe 12 contacts the cornea of the eye E to be examined is subjected to counting processing etc. in the ultrasonic signal processing circuit 33, and similarly processed by the calculation circuit 30 to the cornea of the eye E to be examined. Find the axial length. Note that the two-dimensional image sensor 7
can be used not only for measurement signal detection but also as an anterior segment observation mechanism for the eye E to be examined, and alignment can be performed by operating the sliding table 1 while observing the anterior segment on the television monitor 8.

After measuring the corneal refractive power and axial length of the eye E in this way, the arithmetic circuit 30 uses these values to calculate the refractive power of the IOL using empirically obtained formulas and prints it on the printer 34. .

Here, the above-mentioned corneal refractive power measurement, axial length measurement,
Each printer printing operation is executed via an arithmetic circuit 30 in response to a command from an advance switch 31.

Next, the flow of control in the above configuration will be explained using the flowchart of FIG. Eye to be examined E
In measuring the IOL refractive power, first, each data of the previously measured eye is reset by data reset in step 40, and the arithmetic circuit 30 is initialized. Here, while the alignment operation between the eye E to be examined and the optical axis of the objective lens is being performed, the control is at step 41 and a command from the advance switch 31 is awaited. When the advance switch 31 is turned on, the control moves to step 42 to measure corneal refractive power. After execution of the measurement, the control step is 43, in which it is determined whether the corneal refractive power measurement result is normal or abnormal. If the measurement result is abnormal, the control step is 41.
will be returned to. At this time, a message such as "Cornea refractive power measurement" is displayed on the television monitor 8.

On the other hand, if the measurement result is determined to be normal,
The control proceeds to step 44, where the television monitor 8 is switched to the axial length alignment screen, and the process proceeds to step 45, where the advance switch 31 is commanded. Here, when the advance switch 31 is turned on, the control moves to step 46 and measures the axial length of the eye. After the measurement is executed, the control goes to step 47 and it is determined whether the measurement result of the axial length is normal or abnormal. Here, a comparison is made with the reliability of measurements such as the standard deviation included in the measurement results of the corneal refractive power that have already been obtained, and only when the measurement reliability of the corneal refractive power measurement and the axial length measurement are at the same level. It is determined to be normal.

As a result, if the measurement result of the axial length is abnormal,
A message such as "Ocular axial length re-measurement" is displayed on the television monitor 8, and the control returns to step 44.

If the measurement result of the axial length is determined to be normal, the control proceeds to step 48, in which the refractive power of the IOL is calculated using the corneal refractive power data and the axial length data obtained so far. Execute.

After executing the IOL calculation, the control proceeds to step 49, where a command from the advance switch 31 is received.

Here, when the advance switch 31 is turned on, the control proceeds to step 50, where the data such as the corneal refractive power, ocular axial length, and IOL refractive power obtained above are printed on the printer 34.

When the printing operation is completed, the control step returns to step 4.
Returning to 0, the device is initialized for measurement of a new eye to be examined.

In the above-mentioned embodiment, the number of times of measurement trials for each of the corneal refractive power measurement and the axial length measurement was explained as one, but it may be programmed in advance so that the number of measurement trials is multiple.

〔Effect of the invention〕

As explained above, according to the present invention, the operation of two measuring systems with different functions becomes simple and accurate.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram, FIG. 2 is a front view of an example of the arrangement of projection index light sources, FIG. 3 is a block diagram of the main parts of the signal processing system, and FIG. 4 is a control flowchart. DESCRIPTION OF SYMBOLS 1... Sliding table, 2... Main body, 3... Objective lens, 7... Two-dimensional image sensor, 8... Television monitor, 9, 16... Electric motor, 10, 17... Wire, 11a to 11d... ...Projection target light source, 12...
Ultrasonic probe, 13... Probe holder, 14...
Sliding guide member, 15...Tension spring, 30...
...Arithmetic circuit, 31...Advance switch, 32
...Video signal processing circuit, 33...Ultrasonic signal processing circuit, 34...Printer.

Claims (1)

[Scope of Claims] 1. A first measurement system that detects information on a first eye to be examined while maintaining a predetermined distance from the eye to be examined; In the ophthalmological apparatus, the ophthalmological apparatus is provided with a second measurement system for detecting eye information to be examined in the same measuring instrument main body, and is capable of switching between the first and second measurement systems while the position of the eye to be examined is fixed. a determining means for determining whether the measurement result of the first measuring system or the second measuring system is in a predetermined state;
An ophthalmologic apparatus characterized by having means for switching a measurement system. 2. The ophthalmologic apparatus according to claim 1, wherein after the measurement results of the first and second measurement systems are obtained, the measurement results are reset and initialized. 3. The ophthalmologic apparatus according to claim 1, wherein the first measuring system is a corneal refractive power measuring means, and the second measuring system is an ultrasonic axial length measuring means.