JP2009254779A - Ophthalmological ultrasonic diagnostic system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable measurement result by performing measurement with an ultrasonic prove correctly contacted with the cornea. <P>SOLUTION: In an ophthalmological ultrasonic diagnostic system for measuring an eyeball length according to reflected echo obtained by the ultrasonic probe brought into contact with the cornea to be tested, a pressure sensor for detecting pressure when the ultrasonic probe is brought into contact with the cornea is provided with: a plurality of pressure sensors provided at the distal end of the ultrasonic probe in such a manner where imbalance of upward/downward/rightward/leftward contacting pressure with respect to the cornea can be detected; a judgment means which judges the tilt of the ultrasonic probe with respect to the cornea according to pressure detected by each pressure sensor; and a reporting means which reports a judgment result obtained by the judgment means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ophthalmic ultrasonic diagnostic apparatus that measures the axial length of an eye to be examined using an ultrasonic probe.

2. Description of the Related Art An ophthalmic ultrasonic diagnostic apparatus is known in which the tip of an ultrasonic probe that transmits and receives ultrasonic waves is brought into contact with an eye cornea to be examined and the axial length is measured based on a reflected echo obtained by the probe (for example, a patent References 1 and 2).
JP 2001187702 A JP 2007-319337 A

  When measuring with an ultrasonic probe, it is necessary to bring the tip of the probe into contact with the cornea of the subject's eye so that the axis of the probe matches the visual axis of the subject's eye. In the alignment in which the probe is brought into contact with the cornea of the subject's eye, the distance between the probe and the cornea is determined based on the sense of the examiner, and the probe is not in contact with the cornea, but is preferably brought into contact with the cornea. Moreover, in the positioning of the probe after the probe is brought into contact with the cornea, the cornea may be deformed by a force (contact pressure) pressing the probe brought into contact with the cornea, and the measurement result is affected. Even in such a case, the examiner sensuously determines the contact state of the probe and adjusts the contact pressure based on experience.

  When measuring with an ultrasonic probe, the tip of the probe is brought into contact with the cornea so that the visual axis of the eye to be examined is aligned with the axis of the probe while the visual axis of the eye to be examined is guided by a fixation lamp built in the probe. There is a need. However, whether the probe is correctly in contact with the cornea has been judged by the examiner by visual observation of the fingertip sensation and probe contact. For this reason, when an examiner who is not accustomed to the examination performs the measurement, the measurement may be performed with the probe tilted with respect to the cornea. In this case, the reliability of the measurement result becomes poor, and there is a difference in the prescription value of the intraocular lens (IOL) determined based on the axial length. FIG. 7 shows the result of simulating the relationship between the tilt angle and the axial length when the probe is measured with respect to the visual axis O (normal direction of the cornea) of the eye. At the same time, the power of the intraocular lens (IOL) prescribed according to the axial length is simultaneously shown. According to this simulation result, when the tilt angle of the probe is 5 degrees, the power of the prescribed IOL also greatly differs.

  In view of the above problems, it is an object of the present invention to provide an ophthalmic ultrasonic diagnostic apparatus that can measure an ultrasonic probe correctly in contact with the cornea and obtain a highly reliable measurement result.

In order to solve the above problems, the present invention is characterized by having the following configuration.
(1) In an ophthalmic ultrasonic diagnostic apparatus that measures the axial length based on a reflected echo obtained by an ultrasonic probe brought into contact with an eye cornea to be examined, the pressure when the ultrasonic probe is brought into contact with the cornea is detected. And a plurality of pressure sensors provided at the tip of the ultrasonic probe so as to be able to detect the contact pressure imbalance in the vertical and horizontal directions with respect to the cornea, and based on the pressure detected by the pressure sensors. It is characterized by comprising determination means for determining the inclination of the ultrasonic probe with respect to the cornea and notification means for notifying the determination result by the determination means.
(2) In the ophthalmic ultrasonic diagnostic apparatus according to (1), at least three pressure sensors are arranged outside an ultrasonic transducer built in an ultrasonic probe.
(3) In the ophthalmic ultrasonic diagnostic apparatus according to (2), an identifier for identifying the vertical and horizontal directions when the ultrasonic probe is brought into contact with the cornea is attached to the ultrasonic probe. It is arranged in a predetermined positional relationship with the identifier.
(4) The ophthalmic ultrasonic diagnostic apparatus according to any one of (1) to (3) is configured to determine whether a contact pressure detected by the plurality of pressure sensors exceeds a predetermined upper limit value. And a second notification unit that notifies the determination result of the second determination unit.
(5) In the ophthalmic ultrasonic diagnostic apparatus according to (1), the pressure sensor has a pressure detection surface disposed on a contact surface of the ultrasonic probe or a pressure transmission medium interposed between the contact surfaces of the ultrasonic probe. It is arranged inside the probe.
(6) In an ophthalmic ultrasonic diagnostic apparatus that measures the axial length based on a reflected echo obtained by an ultrasonic probe brought into contact with the subject's eye cornea, the pressure when the ultrasonic probe is brought into contact with the cornea is detected. A pressure sensor provided on a contact surface in contact with the cornea at the tip of the ultrasonic probe, and a determination for determining a contact pressure of the ultrasonic probe with respect to the cornea based on a pressure detected by the pressure sensor Means and a notifying means for notifying the determination result by the determining means.
(7) In the ophthalmic ultrasonic diagnostic apparatus according to (6), the ultrasonic probe includes a distance sensor that detects a distance from the tip of the ultrasonic probe to the cornea of the eye to be examined, and a distance detected by the distance sensor. And informing means for informing distance information.
(8) In the ophthalmic ultrasonic diagnostic apparatus according to (7), the ultrasonic probe includes a light source for a fixation lamp that guides fixation of an eye to be examined, and light from the fixation lamp light source. A light guide path that guides light along an axis, and the distance sensor is an optical distance sensor that detects the distance via the light guide path.

  According to the present invention, the ultrasonic probe can be measured in contact with the cornea correctly, and a highly reliable measurement result can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic external view of an ophthalmic ultrasonic diagnostic apparatus according to this embodiment. An ultrasonic probe 2 for A mode having a transducer 12 (see FIGS. 2 and 3) for transmitting and receiving ultrasonic waves is connected to the apparatus main body 1. A liquid crystal display panel 3 capable of color display is provided on the front surface of the apparatus body 1. The display panel 3 has a touch panel function, and the measurer can set various conditions by selecting and operating setting items displayed on the display panel 3. The display panel 3 displays the measurement result of the reflected echo waveform of the eyeball obtained by the ultrasonic probe 2, the axial length, and the like, as well as the suitability of the tilt of the probe 2 with respect to the eye to be examined, and tilt correction information. The

  FIG. 2A is a perspective view of the distal end portion of the probe 2, and FIG. 2B is a cross-sectional view of the distal end portion of the probe 2. The tip of the probe 2 is formed to have a diameter of about 8 mm, and a plurality of pressure sensors 20 for detecting a contact pressure when the probe 2 is brought into contact with the cornea are arranged at the tip thereof. The pressure sensor 20 is arranged so as to be able to detect an imbalance of the contact pressure in the vertical and horizontal directions with respect to the cornea. In the example of FIG. 2A, four pressure sensors 20 (20A, 20B, 20C, 20D) are arranged in the vertical and horizontal directions. As the pressure sensor 20, a commercially available small semiconductor pressure sensor can be used. In the present embodiment, the pressure sensor 20 is disposed outside the transducer 12 so as not to hinder the transmission and reception of ultrasonic waves by the transducer 12 disposed in the center of the probe 2. Further, as shown in FIG. 2A, the pressure sensor 20 may be disposed on the distal end surface (contact surface) 2a so that the detection surface directly contacts the cornea. However, since the distal end surface 2a of the probe 2 is formed in a concave shape so as to substantially coincide with the curved surface of the cornea, the pressure sensor 20 indirectly increases the contact pressure with the cornea as shown in FIG. It is preferable that it is provided so that it can be detected.

  In FIG. 2B, the four pressure sensors 20 (20A, 20B, 20C, 20D) are respectively embedded in the distal end surface 2a or the rear side of the probe 2, and the detection surface and the distal end surface of the pressure sensor 20 are arranged. Between 2a, a pressure transmission medium 22 such as oil which does not corrode metal is filled. A deformable thin film 23 such as a resin is formed on the tip side of the pressure transmission medium 22. The thin film 23 is configured to protrude slightly from the curved tip surface 2a. When the distal end surface 2a of the probe 2 comes into contact with the curved surface of the cornea, the thin film 23 is deformed rearward of the probe 2, and the pressure sensor 20 causes the contact pressure with the cornea to be changed via the pressure transmission medium 22 filled therein. Detected.

  A fixation lamp 30 is disposed inside the probe 2. The fixation lamp 30 is placed on the central axis L of the probe 2 behind the transducer 12. A path (light guide path) 12 a through which visible light from the fixation lamp 30 can pass is formed at the center of the transducer 12. When the probe 2 is brought into contact with the subject's eye cornea, the visual axis of the subject's eye is guided in the direction of the central axis of the probe 2 by causing the subject's eye to fixate the fixation lamp 30.

  In addition, although the four pressure sensors 20 are used in the example of FIG. 2, the pressure sensor 20 can detect the imbalance of the contact pressure in the vertical and horizontal directions with respect to the cornea when the probe 2 is in contact with the cornea. It suffices if a plurality of positions are arranged. If at least three pressure sensors 20 are not in a straight line, the inclination of the probe 2 in the vertical and horizontal directions with respect to the cornea can be determined from the contact pressure balance detected by the three pressure sensors 20.

  On the outer peripheral side surface of the probe 2, a mark (identifier) 21 for identifying an up / down / left / right direction when the examiner brings the probe 2 into contact with the subject's eye is attached. The plurality of pressure sensors 20 are in a predetermined positional relationship promised in advance with the mark 21. That is, in the example of FIG. 2A, the pressure sensor 20 </ b> A among the four pressure sensors 20 corresponds to the direction of the mark 21. When the examiner brings the probe 2 into contact with the eye to be examined, assuming that the mark 21 is positioned above the eye to be examined, the pressure sensor 20B corresponds to the right direction with respect to the eye to be examined, and the pressure sensor 20C is left. Corresponding to the direction, the pressure sensor 20D corresponds to the downward direction. Moreover, the control part 10 mentioned later can determine the up-down direction of the inclination of the probe 2 by the promise of the arrangement relationship between the mark 21 and the pressure sensor 20. The mark 21 for identifying the up / down / left / right direction of the probe 2 is configured to be visually recognizable, and to form an unevenness on the outer peripheral side surface of the probe 2 so that it can be recognized when the examiner touches it with a fingertip. But it ’s okay.

  FIG. 3 is a configuration diagram of a control system of the ophthalmic ultrasonic diagnostic apparatus. The control unit 10 is built in the apparatus main body 1 and controls various circuits. The control unit 10 drives and controls the clock generation circuit 11 and oscillates ultrasonic waves from the transducer 12 provided in the probe 2 via the transmitter 17. During measurement, when the examiner brings the tip of the probe 2 into contact with the cornea, the reflected echo from each tissue of the eye to be examined is received by the transducer 12 and converted into a digital signal by the A / D converter 13 via the amplifier 18. The The reflected echo information converted into a digital signal is stored in the sampling memory 14. Then, the control unit 10 obtains a measurement value of the axial length of the eye to be examined by obtaining the length from the corneal echo to the retinal echo based on the reflected echo information stored in the sampling memory 14. The measurement result is displayed on the display panel 3.

  The pressure signals detected by the four pressure sensors 20 are converted into digital signals by the A / D converter 18 via the amplifiers 17 and input to the control unit 10. The control unit 10 determines whether the inclination of the probe 2 is appropriate and in which direction it is inclined based on the imbalance of the contact pressure detected by the four pressure sensors 20.

  FIG. 4A shows an example of a measurement screen 60 displayed on the display panel 3. On the measurement screen 60, a left / right eye switch 61 for selecting the subject's measurement eye, a switch 62 for selecting a measurement mode such as auto measurement / manual measurement, and the waveform of the reflected echo obtained by the probe 2 are displayed. A waveform display field 63, a measurement result display field 64 such as an axial length, a measurement switch 65 for starting sampling data sampling, a warning display field 70 for tilt information of the probe 2, and the like. . FIG. 4B is a display example of the warning display column 70.

  Next, the operation of this apparatus will be described. On the measurement screen 60, the measurement eye is selected by the left / right eye switch 61, and the measurement mode is selected by the measurement mode switch 62. Here, a case where the auto measurement mode is selected will be described. In the auto measurement mode, the control unit 10 determines whether the measurement value and waveform data are appropriate, and when a predetermined number (10) of valid data that falls within a predetermined variation tolerance range is obtained, the measurement is automatically stopped. The

  After setting the conditions necessary for measurement, the examiner holds the probe 2 so that the mark 21 is positioned upward with respect to the subject's eye, and aligns the tip of the probe 2 with the pupil center of the subject's eye. Meanwhile, the distal end surface 2a of the probe 2 is brought into contact with the cornea of the patient's eye. The visual axis of the eye to be examined is guided to the central axis L of the probe 2 by fixing the fixation lamp 30 positioned at the inner center of the probe 2 to the eye to be examined. At this time, if measurement is performed with the probe 2 tilted with respect to the cornea, the measurement result of the axial length cannot be obtained accurately. When the distal end surface 2a of the probe 2 is brought into contact with the cornea, the suitability of the inclination of the probe 2 with respect to the eye cornea to be examined is determined based on the balance of pressure signals detected by the four pressure sensors 20, and the probe 2 is inclined. In this case, the direction in which the inclination should be corrected is displayed in the warning display field 70.

  A method by which the control unit 10 determines the inclination of the probe 2 will be described with reference to FIGS. 5 and 6. FIG. 5A shows an example in which the probe 2 is tilted upward (in the direction of the pressure sensor 20A) and is in contact with the subject's eye cornea. FIG. 5B is an example in which the probe 2 is properly inspected. It is an example when it is touched. FIGS. 6A and 6B are views showing pressures detected by the pressure sensors 20A, 20B, 20C, and 20D when the probe 2 shown in FIGS. 5A and 5B is in contact. It is. The bar graphs 50A, 50B, 50C, and 50D shown in FIGS. 6A and 6B correspond to the magnitudes of pressure detected by the pressure sensors 20A, 20B, 20C, and 20D, respectively. When the probe 2 is correctly in contact with the cornea, the pressures detected by the pressure sensors 20 are substantially balanced. In this case, the central axis L of the probe 2 is approximately in the normal direction of the cornea having a curved surface. It can be regarded as a state of matching.

  6A and 6B, “AVE” is an average value of the four pressures calculated by the control unit 10. “MAX” is a value set as an upper limit pressure when the probe 2 is brought into contact with the cornea. When a pressure exceeding “MAX” is applied, the cornea is deformed, indicating that it is difficult to obtain an accurate axial length. “MIN” is a value set as the lower limit pressure when the probe 2 is brought into contact with the cornea. When the pressure is lower than this, the possibility that the probe 2 is not in contact with the cornea is increased. The values of “MAX” and “MIN” are determined by experiments.

  The control unit 10 determines whether or not the pressure detected by each pressure sensor 20 is within a preset allowable range W around the average value AVE of pressure. As shown in FIG. 5B, if the pressure detected by each pressure sensor 20 is within the allowable range W, that is, if the pressure detected by each pressure sensor 20 is substantially equal, the cornea of the probe 2 with respect to the cornea Is determined to be appropriate.

  On the other hand, as shown in FIG. 6A, when the pressure detected by the pressure sensor 20A is higher than the allowable range W and the pressure detected by the pressure sensor 20D is lower than the allowable range W, the probe 2 moves upward. It is determined that it is tilted. In addition, since the pressure detected by the pressure sensors 20B and 20C is substantially equal, it is determined that there is no inclination in the left-right direction. In this case, a warning sound indicating that the probe 2 is tilted is emitted from the speaker 16 and the appropriateness of the tilt of the probe 2 and the direction in which the tilt of the probe 2 should be corrected are displayed in the warning display field 70 of the display panel 3. Is done.

  The warning display in the warning display column 70 will be described. FIG. 4B is a diagram for explaining a warning display example in the warning display column 70. The warning display column 70 includes a center graphic 71 and indicators 72A, 72B, 72C, 72D arranged in the upward / leftward / rightward / downward direction corresponding to the pressure sensors 20A, 20B, 20C, 20D, Have The center graphic 71 is displayed in green when the inclination of the probe 1 is appropriate, and is displayed in warning in red when the inclination of the probe 2 needs to be corrected. The graphic length of the indicators 72A, 72B, 72C, 72D is increased or decreased according to the pressure detected by each pressure sensor 20. In the example of FIG. 6A, the probe 22 is tilted upward, and correction of the tilt is necessary, so the center graphic 71 is displayed in red. From this display and the warning sound from the speaker 19, the examiner can know that the inclination of the probe 2 should be corrected. Further, the graphic of the indicator 72A is displayed long, and the graphic of the indicator 72D is displayed short. The graphics of the indicators 72B and 72C are displayed with the same length. Thereby, the examiner can know that the probe 2 should be inclined downward. Further, the correction amount of the inclination of the probe 2 can be grasped by the graphic length of the indicators 72A and 72D.

  When the examiner corrects the inclination of the probe 2 and the balance of pressures detected by the pressure sensors 20 becomes substantially equal as shown in FIG. 6B, the indicators 72A to 72D are displayed with the same length, The graphic 71 is changed to green display. Thereby, the examiner can know that the probe 2 is correctly in contact with the cornea. If the display colors of the indicators 72A to 72D are changed from green to red as the graphic length increases, the degree of pressure with which the probe 2 is in contact and the inclination of the probe 2 are further increased. You can easily know the degree visually.

  In addition, when the pressure detected by each pressure sensor 20 exceeds the upper limit pressure value “MAX”, the graphics of the respective indicators 72A to 72D are displayed long and displayed in red. Thereby, the examiner can know that the probe 2 has been brought into contact with the cornea too much. In this case, the examiner weakens the force for pressing the probe 2 in contact with the cornea. Conversely, when the pressure detected by each pressure sensor 20 is below the lower limit pressure value “MIN”, the indicators 72A to 72D are not displayed. Thereby, the examiner can know that the probe 2 is not in proper contact with the cornea.

  As a method for prompting the examiner to correct the inclination of the probe 2, the probe 19 may be indicated by voice. For example, “UP” when the probe 2 is tilted upward, “DOWN” for the downward direction, “LEFT” for the left direction, “RIGHT” for the right direction, etc. You may notify by voice.

  Further, four LEDs corresponding to the pressure sensors 20A to 20D may be incorporated in the vicinity of the tip of the probe 2, and when an error due to the inclination of the probe 2 occurs, the corresponding LED may be turned on. Alternatively, an error warning may be issued by changing the color of the LED. For example, when the probe 2 is not in contact with the subject's eye, the LED is not lit, and when each pressure sensor is in contact with the subject's eye, each LED is lit in green. When an error occurs, the corresponding LED color is switched to red.

  The examiner corrects the inclination of the probe 2 according to the warning display column 70 or the warning from the speaker 19, and then observes the reflected echo waveform displayed at any time in the waveform display column 63, and when the appropriate image is obtained, the measurement start switch 65 Press (or foot switch not shown). When the trigger signal from the measurement start switch 65 is received, the control unit 10 reads the data in the sampling memory 14 and determines whether or not the captured waveform is appropriate. When an appropriate waveform is obtained, the control unit 10 calculates the axial length, anterior chamber depth, lens thickness, vitreous body length, and the like, and displays the calculation result on the screen together with the reflected echo waveform image (still image). When ten measurement results are obtained, the measurement is automatically terminated.

  As described above, when the probe 2 is in contact with the subject's eye with an inclination, a warning is given to the examiner and the inclination direction of the probe 2 (the direction in which the inclination is to be corrected) is indicated. The examiner can easily correct the inclination of the probe 2. Therefore, the axial length can be measured in a state where the probe 2 is properly brought into contact with the cornea of the subject, and the axial length can be measured more accurately. For this reason, intraocular lenses are also properly prescribed.

  Next, a modified example of the present invention will be described. In the above explanation, a plurality of pressure sensors are arranged on the probe to detect the inclination of the probe brought into contact with the cornea and to detect the contact pressure (contact state) of the probe. It is good also as a structure which detects and alert | reports to an examiner and makes a probe contact the cornea suitably (alignment of the probe with respect to a cornea is performed suitably).

  FIG. 8 is a diagram for explaining the configuration of the probe 5 of the modification example. FIG. 8A is a perspective view of the distal end portion of the probe 5, and FIG. 8B is a cross-sectional view of the distal end portion of the probe 5. For the sake of simplicity of explanation, the same members as those in the above-described probe are denoted by the same reference numerals. In addition, each member of the probe 5 is connected to the control unit 10 and the like as described above.

  It is assumed that the distal end surface 5a in contact with the cornea in the probe 5 has a curvature along the cornea or a curvature slightly larger than the curvature of the cornea. In the tip surface 5a having such a shape, the front surface of the contact surface 5a contacts the cornea having various shapes. For this reason, when the probe 5 is brought closer to the cornea, the central portion (corneal apex) of the cornea comes into contact with the central portion of the distal end surface 5a first.

  A pressure sensor 25 for detecting the contact pressure of the cornea in contact with the probe 5 is disposed at the tip of the probe 5 as described above. As the pressure sensor 25, a semiconductor pressure sensor is used as in the above-described pressure sensor, and a pressure transmission medium 27 is filled between the detection surface of the pressure sensor 25 and the tip surface 5a. A deformable thin film 28 made of resin or the like is formed on the distal end side of 27. Such a pressure sensor 25 is connected to the control unit 10 and sends information on contact pressure to be detected to the control unit 10. The pressure sensor 25 is disposed on the distal end surface 5a so as to detect the contact pressure of the cornea in contact with the probe 5. Here, the cornea is disposed near the center of the distal end surface 5a, which is the position where the cornea first contacts the distal end surface 5a. As a result, the contact pressure can be detected immediately when the cornea contacts the distal end surface 5a.

  Further, in the probe 5, a passage 12 a that guides light emitted from a fixation lamp (fixation lamp light source) 30 that guides fixation of the eye to be examined to the distal end surface 5 a is along the axis L of the probe 5 a. Are arranged. The leading end side of the passage 12a is located at the center of the contact surface 5a. For this reason, the pressure sensor 25 is disposed in the vicinity of the passage 12a on the distal end surface 5a and in the vicinity (substantially the center) of the central portion of the distal end surface 5a.

  Since the pressure sensor 25 is disposed in the vicinity of the center portion of the distal end surface 5 a, the transducer 12 disposed in the center portion of the probe 5 is disposed behind the pressure sensor 25. Here, the pressure sensor 25 is configured to be as small as possible (small in diameter) so as not to obstruct the transmission and reception of ultrasonic waves by the transducer 12. In addition, here, any configuration can be used as long as the contact pressure of the cornea in contact with the probe 5 can be detected. Therefore, the number of arrangements is as small as possible within the range in which the contact pressure can be detected. As shown in FIG. 8A, the pressure sensor 25 may be disposed on the distal end surface (contact surface) 5a so that its detection surface directly contacts the cornea.

  The pressure detected by the pressure sensor 25 is sent to the control unit 10 as described above. Although illustration of the structure which alert | reports to the examiner the contact pressure of the probe 5 and cornea by the detected pressure is abbreviate | omitted, it is the same as the display in the above-mentioned warning display column. Since the detected contact pressure is information from one pressure sensor 25, the pressure of the pressure sensor 25 is notified using one of the four indicators described above. Here, as described above, “MAX” is a value set as an upper limit pressure when the probe 5 is brought into contact with the cornea. When a pressure exceeding “MAX” is applied, the cornea is deformed, and the accurate It is difficult to obtain the axial length. “MIN” is a value set as the lower limit pressure when the probe 5 is brought into contact with the cornea. When the pressure is lower than this, there is a high possibility that the probe 5 is not in contact with the cornea. The values of “MAX” and “MIN” are determined by experiments. Note that the values of “MAX” and “MIN” may differ depending on where the pressure sensor 25 is disposed. In this case, the relationship between the arrangement position of the pressure sensor 25 (position on the distal end surface 5a) and the cornea in contact with it is quantitatively obtained by experiments or the like, and information such as the obtained relational expression and the arrangement position of the pressure sensor 25 To determine the values of “MAX” and “MIN”.

  The control unit 10 determines whether or not the pressure detected by the pressure sensor 25 is between “MIN” and “MAX”. Based on the determination result, the control unit 10 emits a warning sound from the speaker 19 and displays the contact pressure of the probe 5 on the indicator in the warning display column of the display panel 3 using the indicator.

  By arranging the pressure sensor at the tip of the probe as described above, the contact state (contact pressure) between the probe and the cornea can be detected, and the information can be notified to the examiner. Since the examiner can know the contact pressure of the probe, the contact pressure of the probe can be suitably used. Thus, the probe can be suitably aligned, and measurement can be performed with the probe correctly in contact with the cornea. Furthermore, highly reliable measurement results can be obtained.

  In the modification example described above, the pressure sensor is disposed near the center of the tip of the probe, but the present invention is not limited to this. Any configuration is possible as long as the contact pressure of the cornea in contact with the probe can be detected by the pressure sensor, and it is sufficient that the pressure sensor is disposed in a range where the cornea contacts the distal end surface. It is good also as a structure which arrange | positions a pressure sensor in the outer peripheral side rather than center part vicinity of a front end surface. For example, if the pressure sensor is arranged at the periphery of the tip of the probe as in the above-described embodiment, the pressure sensor is arranged outside the transducer, so that the transmission and reception waves transmitted and received by the transducer are not hindered. it can.

  In the above description, the display panel 3 is configured to notify the examiner of pressure information. However, the present invention is not limited to this. What is necessary is just to be able to notify the examiner of pressure information, and it is also possible to employ a configuration in which a speaker is used to notify by sound.

  Next, a second modification example will be described. In the above description, in order to suitably align the probe and the cornea, the contact pressure (contact state) is detected by the pressure sensor arranged at the tip of the probe and is notified to the examiner. In order to suitably contact the probe and the cornea, a configuration may be added in which the distance between the probe and the cornea is detected and notified to the examiner.

  FIG. 9 is a diagram illustrating the configuration of the probe 6 of the second modification example. FIG. 9A is a perspective view of the distal end portion of the probe 6, and FIG. 9B is a cross-sectional view of the distal end portion of the probe 6. For the sake of simplicity of explanation, the same members as those in the above-described probe are denoted by the same reference numerals. Each member of the probe 6 is connected to the control unit 10 and the like as described above.

  A pressure sensor 25 for detecting the contact pressure of the cornea in contact with the probe 6 is disposed at the tip of the probe 6 as described above. Here, the probe 6 has a fixation lamp 30 that emits visible light to guide fixation of the eye to be inspected, and a passage that guides light emitted from the fixation lamp 30 to the distal end surface 6a (light guide path). 12a. The passage 12a is disposed along the axis L of the probe 5a and is located at the center of the distal end surface 6a (dotted line in FIG. 9A). The fixation lamp 30 is disposed on the axis L behind the passage 12a. In addition, a distance sensor 40 for detecting the distance between the probe 6 and the cornea in a non-contact manner is disposed behind the passage 12 a, and on the axis L between the passage 12 a and the fixation lamp 30. A beam splitter 41 for making the optical axis of the distance sensor 40 coaxial with the axis L is disposed. Here, the distance sensor 40 is an optical distance sensor using infrared light as measurement light, here, a light position sensor (PSD). The beam splitter 41 has a characteristic of transmitting visible light emitted from the fixation lamp 30 and reflecting infrared light received and emitted by the distance sensor 40. The distance sensor 40 is connected to the control unit 10.

  The measurement light of the distance sensor 40 is received and emitted through the passage 12a located at the center of the distal end surface 6a. For this reason, the distance sensor 40 detects the distance between the cornea and the distal end surface 6a based on the reflected light from the apex of the cornea. The distance information detected by the distance sensor 40 is sent to the control unit 10, and the control unit 10 considers the optical distance from the distance sensor 40 to the distal end surface 6a, and the distance between the distal end surface 6a and the cornea. Get.

  The control unit 10 emits sound from the speaker 19 according to the distance information obtained based on the signal from the distance sensor 40, and notifies the examiner of the distance between the probe 6 (tip surface 6a) and the cornea. For example, the notification by sound is performed by changing a sound interval. Specifically, as the distance between the probe 6 and the cornea becomes shorter, the interval between the intermittent sounds is shortened so that the continuous sound is obtained when the probe 6 and the cornea are in contact with each other. For example, when the distance between the probe 6 and the cornea is 50 mm, the interval between intermittent sounds of “beep” and “beep” is 0.5 seconds, and when the distance is 20 mm, the interval between intermittent sounds. 0.2 seconds. When the distance is 0 mm, that is, when the probe 6 and the cornea are in contact with each other, the above-mentioned intermittent sound is defined as a continuous sound “P”. At this time, the control unit 10 stops the continuous sound based on the detection signal from the pressure sensor 25, that is, information that is in a state that can be measured by contacting the probe 6 and the cornea. When the probe 6 is separated from the cornea, the control unit 10 generates an intermittent sound again from the speaker 19.

  As described above, the distance between the probe and the cornea can be detected and the distance can be notified to the examiner. For this reason, it becomes easy to avoid applying the probe to the cornea vigorously in the alignment of the probe. Thus, the probe can be suitably aligned, and measurement can be performed with the probe correctly in contact with the cornea. Furthermore, highly reliable measurement results can be obtained. Further, by notifying the examiner of the distance between the probe 6 and the cornea based on the sound information, the examiner can align the probe 6 while viewing the distal end surface 6 a of the probe 6. The display panel 3 may display the distance between the probe 6 and the cornea and visually notify the examiner of the distance.

  In the present embodiment described above, an optical distance sensor is used to detect the distance between the probe and the cornea. However, the present invention is not limited to this. Any configuration that can detect the distance between the probe and the cornea may be used, and a distance sensor using ultrasonic waves may be used. For example, a configuration is used in which ultrasonic waves in a frequency band different from the ultrasonic waves for measuring diagnostic information are used.

  In the above description, the pressure sensor and the distance sensor are arranged on the probe. However, the present invention is not limited to this. Any configuration may be used as long as the probe can be suitably brought into contact with the cornea, and only the distance sensor may be arranged on the probe.

1 is a schematic external view of an ophthalmic ultrasonic diagnostic apparatus. It is the perspective view and sectional drawing of a probe front-end | tip part. It is a block diagram of the control system of the ophthalmic ultrasonic diagnostic apparatus. It is a display example of a measurement screen and a warning display column. It is a figure explaining the case where a probe inclines in contact with a subject's eye cornea, and the case where it contacts appropriately. It is a figure which shows the pressure which each pressure sensor detected in the contact state of each probe of FIG. It is a simulation result of the relationship between the tilt angle of the probe and the axial length. It is the perspective view and sectional drawing of the probe front-end | tip part of a modification example. It is the perspective view and sectional drawing of the probe front-end | tip part of a 2nd modification example.

Explanation of symbols

2, 5, 6 Ultrasonic probe 2a, 5a, 6a Tip surface (contact surface)
3 Liquid Crystal Display Panel 10 Control Unit 12 Transducer 12a Passage 19 Speaker 20, 25 Pressure Sensor 21 Mark (Identifier)
22 Pressure transmission medium 60 Measurement screen 70 Warning display field

Claims (8)

In an ophthalmic ultrasonic diagnostic apparatus for measuring an axial length based on a reflected echo obtained by an ultrasonic probe brought into contact with an eye cornea to be examined,
A pressure sensor for detecting pressure when an ultrasonic probe is brought into contact with the cornea, and a plurality of pressure sensors provided at the tip of the ultrasonic probe so as to detect imbalance in contact pressure in the vertical and horizontal directions with respect to the cornea When,
Determination means for determining the inclination of the ultrasonic probe with respect to the cornea based on the pressure detected by each of the pressure sensors;
Notification means for notifying the determination result by the determination means;
An ophthalmic ultrasonic diagnostic apparatus comprising: 2. The ophthalmic ultrasonic diagnostic apparatus according to claim 1, wherein at least three of the pressure sensors are arranged outside an ultrasonic transducer incorporated in an ultrasonic probe. . The ophthalmic ultrasonic diagnostic apparatus according to claim 2, wherein an identifier for identifying an up / down / left / right direction when the ultrasonic probe is brought into contact with the cornea is attached to the ultrasonic probe, and the plurality of pressure sensors correspond to the identifier. And an ultrasonic diagnostic apparatus for ophthalmology characterized by being arranged in a predetermined positional relationship. The ophthalmic ultrasonic diagnostic apparatus according to any one of claims 1 to 3, a second determination unit that determines whether or not a contact pressure detected by the plurality of pressure sensors exceeds a predetermined upper limit value; An ophthalmic ultrasonic diagnostic apparatus comprising: a second notification unit that notifies a determination result of the second determination unit. 2. The ophthalmic ultrasonic diagnostic apparatus according to claim 1, wherein the pressure sensor has a pressure detection surface disposed on a contact surface of the ultrasonic probe, or a pressure transmission medium interposed in the contact surface of the ultrasonic probe. An ultrasonic diagnostic apparatus for ophthalmology characterized by being arranged in In an ophthalmic ultrasonic diagnostic apparatus for measuring an axial length based on a reflected echo obtained by an ultrasonic probe brought into contact with an eye cornea to be examined,
A pressure sensor for detecting a pressure when the ultrasonic probe is brought into contact with the cornea, the pressure sensor being provided on a contact surface in contact with the cornea at a tip of the ultrasonic probe;
Determination means for determining the contact pressure of the ultrasonic probe with respect to the cornea based on the pressure detected by the pressure sensor;
Notification means for notifying the determination result by the determination means;
An ophthalmic ultrasonic diagnostic apparatus comprising: The ophthalmic ultrasonic diagnostic apparatus according to claim 6,
The ultrasonic probe is a distance sensor that detects the distance from the tip of the ultrasonic probe to the cornea of the eye to be examined;
Informing means for informing distance information according to the distance detected by the distance sensor;
An ophthalmic ultrasonic diagnostic apparatus comprising: The ophthalmic ultrasonic diagnostic apparatus according to claim 7, wherein the ultrasonic probe includes a light source for a fixation lamp that guides fixation of an eye to be examined, and light from the fixation lamp light source along an axis of the ultrasonic probe. And an optical distance sensor for detecting the distance via the light guide path.