WO2008072527A1 - Dispositif de mesure de pression intraoculaire - Google Patents

Dispositif de mesure de pression intraoculaire Download PDF

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Publication number
WO2008072527A1
WO2008072527A1 PCT/JP2007/073512 JP2007073512W WO2008072527A1 WO 2008072527 A1 WO2008072527 A1 WO 2008072527A1 JP 2007073512 W JP2007073512 W JP 2007073512W WO 2008072527 A1 WO2008072527 A1 WO 2008072527A1
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WO
WIPO (PCT)
Prior art keywords
intraocular pressure
eyeball
probe
phase difference
frequency
Prior art date
Application number
PCT/JP2007/073512
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English (en)
Japanese (ja)
Inventor
Sadao Omata
Yoshinobu Murayama
Original Assignee
Nihon University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nihon University filed Critical Nihon University
Priority to JP2008549263A priority Critical patent/JP5505684B2/ja
Publication of WO2008072527A1 publication Critical patent/WO2008072527A1/fr

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00—Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/16—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions for measuring intraocular pressure, e.g. tonometers
    • A61B3/165—Non-contacting tonometers

Definitions

  • the present invention relates to an intraocular pressure measurement device, and more particularly to an intraocular pressure measurement device that measures intraocular pressure using ultrasonic waves.
  • Tonometers are widely used to measure intraocular pressure.
  • the tonometer blows air onto the eyeball, optically measures how the eyeball is distorted by the air pressure, and measures the intraocular pressure based on the magnitude of the distortion.
  • the tonometer blows air onto the eyeball, it is not accurate due to the influence of the pulsation of the air pressure.
  • air is directly injected into the eyeball tissue such as the cornea, a load is applied to the subject.
  • a probe is placed on the heel and appropriately pressurized, and the change in the depth of the anterior chamber at that time is detected by ultrasonic waves.
  • an ultrasonic wave is incident, a reflected sound bundle is detected, and the time axis within one sweep of the ultrasonic detection signal is converted into a distance by the biological sound velocity of the anterior ocular segment for a waveform called ultrasonic A mode.
  • the depth of the anterior chamber is detected by a general distance measurement principle.
  • the present inventor has developed a method capable of accurately measuring the hardness of an object using a phase shift method.
  • vibration is incident on the measurement object from the vibrator, the reflected wave from the measurement object is detected by the vibration detection sensor, and the measurement object is between the incident wave and the reflected wave according to the hardness of the measurement object.
  • the frequency of the generated phase difference using a phase shift circuit, the phase difference is compensated to zero, and the hardness of the measured object is obtained from the amount of frequency change that compensates for the phase difference to zero.
  • the force of measuring the hardness of an object to be measured is measured by a contact method in which vibration is input to the object to be measured and a reflected wave is detected.
  • Patent Document 1 Japanese Patent Laid-Open No. 8-322803
  • Patent Document 2 JP-A-9 145691 Disclosure of the invention
  • the tonometer applies air pressure to the eyeball, and also presses the eyeball through the eyelid in the method of Patent Document 1.
  • pressure is applied to the eyeball by an external force, and the magnitude of the intraocular pressure is determined from the distortion of the eyeball due to the pressure.
  • the hardness of the measurement object can be measured by inputting vibration to the measurement object and detecting the reflected wave.
  • the object to be measured is an eyeball
  • the hardness is related to the intraocular pressure, so this method makes it possible to measure the intraocular pressure without applying external force. multiply. Therefore, if the intraocular pressure can be measured without touching the eyeball, the burden on the subject can be reduced, which is convenient.
  • An object of the present invention is to provide an intraocular pressure measuring device capable of measuring intraocular pressure without contacting the eyeball.
  • vibration is incident on the eyeball in a non-contact manner, a reflected wave from the eyeball is detected, and whether or not the phase shift method can be applied to the phase difference generated between the incident wave and the reflected wave has been confirmed.
  • the tip shape of the probe facing the eyeball is adjusted, there is a correlation between the intraocular pressure and the frequency difference that compensates for the phase difference to zero. Based on this experiment, the following measures can be taken.
  • An intraocular pressure measurement device includes a probe having a transducer that makes ultrasonic waves incident on an eyeball in a non-contact manner, and a vibration detection sensor that detects a reflected wave from the eyeball.
  • a phase difference force S occurs between the input waveform to the transducer and the output waveform from the vibration detection sensor, connected to the probe in series with the amplifier, and a concave acoustic lens with a concave surface facing the eyeball.
  • the phase shift circuit that changes the frequency to compensate for the phase difference to zero, the relationship between the frequency change amount when the phase difference is compensated to zero and the intraocular pressure are obtained in advance, and the concave acoustic lens is attached to the eyeball.
  • the intraocular pressure measurement device preferably includes a probe moving mechanism that can vary the distance between the concave acoustic lens and the eyeball of the measurement object.
  • the intraocular pressure measurement device preferably includes curved surface shape changing means capable of changing the curved surface shape of the concave acoustic lens.
  • the intraocular pressure measurement apparatus uses a probe having a concave acoustic lens whose surface facing the eyeball is a concave surface, and separates the concave acoustic lens from the eyeball so as to face the eyeball. Is incident. Then, the relationship between the frequency change amount and the intraocular pressure when the phase difference is compensated to zero is obtained in advance, and the frequency change force that compensates the phase difference generated when the ultrasonic wave is incident on the eyeball to zero is calculated. calculate. Therefore, the intraocular pressure can be measured without touching the eyeball.
  • the distance between the concave acoustic lens and the eyeball of the measurement object can be varied, it is possible to detect the reflected wave by injecting vibration while focusing on the eyeball.
  • the curved surface shape of the concave acoustic lens can be varied, it is possible to detect the reflected wave by injecting the vibration while focusing on the eyeball.
  • FIG. 1 is a diagram showing a configuration of an intraocular pressure measurement device according to an embodiment of the present invention.
  • FIG. 2 is a diagram extracting and showing a configuration of a probe element, a concave acoustic lens, and a portion of an intraocular pressure measurement unit included in a main body part in an embodiment according to the present invention.
  • FIG. 3 is a diagram showing a state of selection of an oscillation frequency in which the circuit constant of the phase shift circuit is set in the embodiment according to the present invention.
  • FIG. 4 is a diagram showing the shape dimensions of the simulated objects A and B used to obtain the correspondence relationship between the amount of frequency change and the acoustic impedance in the embodiment according to the present invention.
  • FIG. 5 is a diagram showing a correspondence relationship between the amount of change in frequency and acoustic impedance in the embodiment according to the present invention.
  • FIG. 6 is a diagram showing a state of an eyeball model used for obtaining a correspondence relationship between a frequency change amount and intraocular pressure in the embodiment according to the present invention.
  • FIG. 7 shows the correspondence between frequency variation and intraocular pressure in the embodiment of the present invention.
  • the force described as mounting the probe on a movable table movable with respect to the floor may be used.
  • the probe may be mounted on a support base fixed in relation to the head of the subject.
  • the probe may be a force described as a laminate of a transducer and a vibration detection sensor, or any other arrangement method.
  • the vibrator and the vibration detection sensor may be arranged concentrically, or the vibrator and the vibration detection sensor may be separately arranged in parallel.
  • FIG. 1 is a diagram showing a configuration of the intraocular pressure measurement device 10.
  • FIG. 1 shows an eyeball 8 that is not a constituent element of the intraocular pressure measurement device 10 but is an intraocular pressure measurement target.
  • the intraocular pressure measurement device 10 is connected to the probe 20, a probe moving mechanism 30 for adjusting the position of the probe 20 with respect to the eyeball, and the probe 20 via a signal line.
  • a main body 60 that calculates and outputs the value.
  • the probe moving mechanism 30 includes a fixed base 32 fixed to the floor surface and a movable base 34 that can move linearly with respect to the fixed base 32, and a probe is attached to the movable base 34. Part 38 is provided.
  • a conversion mechanism between a rotational motion and a linear motion by a pinion and a rack can be used as the fixed base 32 and the movable base 34.
  • there is an operation node 36 force S connected to the pinion and by rotating the operation handle 36, the pinion provided on the fixed base 32 rotates, and the rack that meshes with this moves linearly.
  • Movable table with rack mounted 34 You can power to move.
  • a linear motor or the like that can be moved by controlling electric signals may be used as a mechanism between the fixed base 32 and the movable base 34! /.
  • the probe 20 is a probe having an elongated cylindrical shape, and is provided with a concave acoustic lens 22 and a probe element 24 on the tip side facing and spaced apart from the eyeball 8, and one end side of the probe element 24 is connected to the probe element 24.
  • the signal line to be connected is connected to the main body 60 on the other end side.
  • FIG. 2 is a diagram showing an extracted configuration of the probe element 24, the concave acoustic lens 22, and the intraocular pressure measurement unit 40 included in the main body 60.
  • the probe element 24 includes a transducer 26 that makes an ultrasonic wave incident on an eyeball 8 that is a measurement object via a concave acoustic lens 22, and a vibration detection sensor 28 that detects a reflected wave from the eyeball 8. And have.
  • the vibrator 26 and the vibration detection sensor 28 are stacked and connected in series, and the connection point is grounded.
  • two disk-shaped piezoelectric elements each provided with electrodes are stacked using two, and the middle two electrodes are integrated into a ground electrode, and the stacked upper surface side electrode and lower surface electrode are integrated.
  • One side of the side electrode is used as the input electrode of the vibrator 26, and the other side is used as the output electrode of the vibration detection sensor 28.
  • the surface on the input electrode side of the vibrator 26 is bonded and fixed to the flat back surface of the concave acoustic lens 22.
  • a commercially available PZT element can be used as the piezoelectric element.
  • the concave acoustic lens 22 focuses the ultrasonic wave radiated from the probe 24 on the measurement object, and efficiently collects the reflected waves radiated from the measurement object. It is an element that has a function to transmit to 24.
  • the concave acoustic lens 22 is formed in a concave surface having a predetermined curved surface on the surface facing the eyeball 8 as a measurement object, and the back surface on the opposite side of the concave surface is formed on, for example, a flat surface to connect to the probe element 24. Is done.
  • the concave acoustic lens 22 may be made of a suitable plastic material or ceramic, glass or the like molded into a predetermined shape.
  • the concave curved surface shape of the concave acoustic lens 22 is preferably a shape corresponding to the curved surface shape of the eyeball 8 to be measured.
  • the force S can be configured as a part of a spherical surface having a certain radius of curvature.
  • the radius of curvature can be the radius of curvature at a site suitable for measuring intraocular pressure, or the average radius of curvature of the eyeball.
  • the force S can be set to a radius of curvature of several millimeters.
  • the concave surface shape of the concave acoustic lens 22 can be formed into a fixed shape by molding an appropriate material as described above.
  • the concave acoustic lens 22 has a fixed end on the outer periphery of a cylindrical support portion.
  • This is a variable-shape concave acoustic lens that has a flexible curved membrane, injects pressurized fluid into the cylindrical support, and changes the shape of the concave surface by changing the fluid pressure.
  • the fluid it is preferable to use a fluid that easily propagates ultrasonic vibrations, and fluid silicone rubber can be used.
  • FIG. 2 shows the configuration of the intraocular pressure measurement unit 40.
  • the intraocular pressure measurement unit 40 includes a terminal 42 that receives an output signal corresponding to the reflected wave from the vibration detection sensor 28, a terminal 44 that outputs an input signal corresponding to the incident wave to the transducer 26, and the main body shown in FIG. A terminal 46 for outputting an intraocular pressure value to an output section such as a display screen of the section 60;
  • the inside of the intraocular pressure measurement unit 40 is configured as follows.
  • the terminal 42 connected to the vibration detection sensor 28 is connected to the amplifier 48 via an appropriate DC cut capacitor.
  • the amplifier 48 is an electronic circuit that appropriately amplifies the reflected wave signal detected by the vibration detection sensor 28, and a known amplifier circuit can be used.
  • phase shift circuit 50 The output of the amplifier 48 is input to the phase shift circuit 50, and the output of the phase shift circuit 50 is connected to the vibrator 26 via the terminal 44. Therefore, transducer 26—concave acoustic lens 2 2-(atmosphere) — (eyeball 8)-(atmosphere) —concave acoustic lens 22—vibration detection sensor 28—amplifier 48—phase shift circuit 50—closed loop of transducer 26 Composed. Therefore, by appropriately setting the contents of the phase shift circuit 50, the force S can be used to generate self-excited oscillation in this closed loop.
  • the function of the phase shift circuit 50 is to change the oscillation frequency of the closed loop when a phase difference occurs between the input signal input to the phase shift circuit 50 and the output signal output in this closed loop. Thus, the phase difference is compensated to zero. Then, the frequency when the phase difference is compensated to zero is output to the frequency change amount calculation unit 52.
  • This function detects the oscillation frequency f when the measurement object is not included in the closed loop and stores it once, and then detects the oscillation frequency f when the measurement object is included in the closed loop. This is also memorized once and the two memorized frequencies f and f are read.
  • the phase shift circuit 50 has a closed-loop frequency when a phase difference occurs between the output signal of the vibration detection sensor 28 and the input signal to the vibrator 26. To compensate for the phase difference to zero. Therefore, as for the frequency of the self-oscillation of the closed loop, the difference in the physical properties of the measurement object becomes easier when the frequency change amount when compensating for the phase difference to zero is large. Therefore, the circuit constants, which are the circuit contents of the phase shift circuit 50, are set so that the frequency change amount when the phase difference is compensated to zero becomes a stable and large oscillation frequency for the target closed loop.
  • FIG. 3 is a diagram showing a state of selection of an oscillation frequency at which the circuit constant of the phase shift circuit 50 is set.
  • FIG. 3 shows the frequency-phase characteristics of the probe element 24.
  • the characteristic of the probe element 24 has a plurality of peaks.
  • Peak B is the peak with the sharpest oscillation characteristics and stable oscillation. Conversely, due to its strong stability, there is almost no frequency change even if the phase difference is changed.
  • Peak C is unstable in oscillation. [0034] Therefore, it is assumed that the peak A causes the oscillation to be properly stabilized, and the force and the frequency change of an appropriate magnitude according to the change of the phase difference. It can be selected as a peak suitable for detection. That is, the circuit constant of the phase shift circuit 50 is set to be suitable around 350 kHz in the frequency band.
  • the intraocular pressure calculation unit 54 has a function of calculating intraocular pressure based on the frequency change amount output from the frequency change amount calculation unit 52.
  • the relationship between the frequency variation and the intraocular pressure is obtained in advance, and the frequency variation calculated by the frequency variation calculator 52 is applied to the relationship.
  • FIG. 4 to FIG. 7 are diagrams for explaining the state of an experiment for determining the relationship between the amount of change in frequency and the intraocular pressure for compensating for the phase difference generated when an ultrasonic wave is incident on the eyeball to zero. These figures show the frequency change amount A f of the frequency f force when there is no simulated object, with respect to the frequency f when the phase difference is compensated to zero by applying ultrasonic waves to the simulated object modeling the eyeball. Seeking
  • FIG. 4 is a diagram for explaining a state in which a relationship between ⁇ f and acoustic impedances of simulated objects A and B is obtained.
  • FIG. 4 shows the geometric dimensions of the simulated objects A and B.
  • the shapes of the simulated objects A and B approximate the outer shape of the eyeball 8, and have a curved surface that is gentler than the hemisphere. From the dimensions in Fig. 4, the radius of curvature at the tip of simulated objects A and B can be evaluated as about 4 mm to about 6 mm.
  • silicon rubber is mixed in an appropriate medium and the concentration is changed to 40%, 60%, 80%, and 100%. A sample was created.
  • the frequency change amount A f that is the change amount of the oscillation frequency between when the simulated objects A and B are present and not present was obtained.
  • Figure 5 shows the result of associating the calculated acoustic impedance with the calculated frequency change.
  • the frequencies of simulated objects A and B with different shapes are There is a correlation between the change A f and the acoustic impedance. According to Fig. 5, the correlation is almost linear, but the correlation varies depending on the shape of the simulated object!
  • FIG. 5 since there is a correlation between the frequency change amount A f when the phase shift method is used and the hardness of the measurement object, the component force, that is, the frequency change amount is described next.
  • Figures 6 and 7 show the experiment of correlating Af with the pressure corresponding to intraocular pressure.
  • a silicone rubber eyeball model 70 having a shape shown in FIG. 6 and having a cavity inside is used as a simulated object modeling the eyeball.
  • the eyeball model 70 is configured to include a base portion 72 and a curved surface portion 74 that can bulge and change its outer shape by pressurizing the inside, and the pressurizer 80 supplies water or an appropriate fluid to the inside of the eyeball model 70.
  • the shape of the curved surface portion 74 can be changed by injecting under pressure.
  • the pressure of the internal fluid in the curved surface portion 74 can be detected by a pressure gauge 82 such as a manometer.
  • FIG. 6 shows how the curved surface portion 74 expands and changes to curved surface portions 75 and 76 as the pressure is increased.
  • FIG. 7 is a diagram showing the relationship between the frequency variation A f and the pressure of the eyeball model 70 when the distance from the concave acoustic lens 22 to the tip of the eyeball model 70 is 2000 m, ie, 2 mm. . As can be seen from FIG. 7, there is a clear linearity between the pressure of the eyeball model 70 and the frequency change ⁇ f in the phase shift method.
  • the intraocular pressure of the eyeball 8 can be obtained by the intraocular pressure measurement device 10 shown in FIG.
  • the correspondence relationship of “A f—intraocular pressure” is stored in a format in which the intraocular pressure is output by inputting A f. Specifically, it may be stored in the form of a calculation formula that may be stored in the form of a conversion table such as a lookup table.
  • f is about 350 kHz because it is the frequency of peak A in Fig. 3.
  • the absence of the eyeball 8 can be realized by providing a sufficiently large space between the eyeball 8 and the tip of the concave acoustic lens 22.
  • the concave acoustic lens 22 is brought closer to the eyeball 8 using the probe moving mechanism 30.
  • the approaching distance is preferably a distance force between the eyeball 8 and the tip of the concave acoustic lens 22 and a representative radius of curvature of the concave acoustic lens 22.
  • a position where the variation in oscillation frequency at that time is reduced can be used as an interval for measurement. That is, if the distance between the eyeball 8 and the concave acoustic lens 22 is too narrow or too wide, the ultrasonic waves diverge or do not concentrate on the curved surface of the concave acoustic lens 22.
  • a f is about 100 Hz in the examples of Figs.
  • the intraocular pressure calculation unit 54 reads the pre-stored “A f—intraocular pressure” correspondence, and applies the frequency change amount A f given from the frequency change amount calculation unit 52 to the correspondence relationship. Calculates and outputs the intraocular pressure.

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Abstract

Un dispositif (10) de mesure de pression intraoculaire comporte une sonde (20) dotée d'une lentille acoustique concave (22) au côté d'extrémité de pointe tourné vers un globe oculaire (8) mais espacé dudit globe oculaire (8) ; un élément de sonde (24) muni d'un vibreur dans lequel est laminé un senseur de détection de vibrations ; un mécanisme (30) de déplacement de sonde pour réguler la position de la sonde (20) par rapport au globe oculaire (8) ; et une unité de corps (60) connectée à la sonde (20) pour calculer et émettre une pression intraoculaire. L'unité de corps (60) inclut un circuit de déphasage connecté en série avec la sonde (20) conjointement à un amplificateur pour changer sa fréquence lorsque la différence de phase entre une forme d'onde d'entrée dans le vibreur et une forme d'onde de sortie provenant du senseur de détection de vibrations se produit, et pour compenser la différence de phase à zéro ; et une unité de calcul de la pression intraoculaire qui détermine à l'avance la relation entre une quantité de changement de fréquence et une pression intraoculaire lorsqu'une différence de phase est compensée à zéro, et qui calcule une pression intraoculaire à partir d'une quantité de changements de fréquence compensant à zéro une différence de phase qui se produit lorsqu'une onde ultrasonore est autorisée à entrer dans le globe oculaire.
PCT/JP2007/073512 2006-12-08 2007-12-05 Dispositif de mesure de pression intraoculaire WO2008072527A1 (fr)

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009268651A (ja) * 2008-05-03 2009-11-19 Nidek Co Ltd 非接触式超音波眼圧計
JP2010068874A (ja) * 2008-09-16 2010-04-02 Nidek Co Ltd 非接触式超音波眼圧計
JP2010068873A (ja) * 2008-09-16 2010-04-02 Nidek Co Ltd 非接触式超音波眼圧計
JP2010082279A (ja) * 2008-09-30 2010-04-15 Nidek Co Ltd 非接触式超音波眼圧計
WO2010087291A1 (fr) * 2009-01-29 2010-08-05 学校法人 日本大学 Dispositif de mesure de pression intraoculaire
US7845235B2 (en) 2007-11-06 2010-12-07 Costin Sandu Non-invasive system and method for measuring vacuum pressure in a fluid
EP2260765A1 (fr) 2009-06-09 2010-12-15 Nidek Co., Ltd Dispositif de mesure ultrasonique sans contact
CN101926659A (zh) * 2009-06-22 2010-12-29 株式会社尼德克 非接触式超声波眼压计
JP2011030756A (ja) * 2009-07-31 2011-02-17 Nidek Co Ltd 非接触式超音波眼圧計
JP2011087900A (ja) * 2009-03-31 2011-05-06 Nidek Co Ltd 非接触式超音波眼圧計
JP2011092598A (ja) * 2009-10-30 2011-05-12 Nidek Co Ltd 非接触式超音波眼圧計
JP2011212124A (ja) * 2010-03-31 2011-10-27 Nidek Co Ltd 非接触式超音波眼圧計
JP2013031767A (ja) * 2012-11-19 2013-02-14 Nidek Co Ltd 非接触式超音波眼圧計
US11406415B2 (en) 2012-06-11 2022-08-09 Tenex Health, Inc. Systems and methods for tissue treatment
US11457937B2 (en) 2014-09-02 2022-10-04 Tenex Health, Inc. Subcutaneous wound debridement

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EP4342362A1 (fr) 2021-05-18 2024-03-27 Quovisu LLC Dispositif de mesure de propriété physique de globe oculaire de type sans contact

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JPH02180241A (ja) * 1988-09-28 1990-07-13 Univ Ohio 非接触超音波眼圧計
JPH05253190A (ja) * 1991-10-10 1993-10-05 Massie Res Lab Inc 非接触式トノメーター
JPH08322803A (ja) * 1995-05-31 1996-12-10 Canon Inc 眼圧計
JPH09145691A (ja) * 1995-09-20 1997-06-06 Sadao Omata 周波数偏差検出回路及びそれを利用した測定器

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7845235B2 (en) 2007-11-06 2010-12-07 Costin Sandu Non-invasive system and method for measuring vacuum pressure in a fluid
JP2009268651A (ja) * 2008-05-03 2009-11-19 Nidek Co Ltd 非接触式超音波眼圧計
JP2010068874A (ja) * 2008-09-16 2010-04-02 Nidek Co Ltd 非接触式超音波眼圧計
JP2010068873A (ja) * 2008-09-16 2010-04-02 Nidek Co Ltd 非接触式超音波眼圧計
JP2010082279A (ja) * 2008-09-30 2010-04-15 Nidek Co Ltd 非接触式超音波眼圧計
WO2010087291A1 (fr) * 2009-01-29 2010-08-05 学校法人 日本大学 Dispositif de mesure de pression intraoculaire
JP2010172464A (ja) * 2009-01-29 2010-08-12 Nihon Univ 眼圧測定装置
JP2011087900A (ja) * 2009-03-31 2011-05-06 Nidek Co Ltd 非接触式超音波眼圧計
US8500638B2 (en) 2009-03-31 2013-08-06 Nidek Co., Ltd. Non-contact ultrasonic tonometer
EP2260765A1 (fr) 2009-06-09 2010-12-15 Nidek Co., Ltd Dispositif de mesure ultrasonique sans contact
CN101926659A (zh) * 2009-06-22 2010-12-29 株式会社尼德克 非接触式超声波眼压计
EP2266454A1 (fr) 2009-06-22 2010-12-29 Nidek Co., Ltd Tonomètre ultrasonique sans contact
JP2011000344A (ja) * 2009-06-22 2011-01-06 Nidek Co Ltd 非接触式超音波眼圧計
JP2011030756A (ja) * 2009-07-31 2011-02-17 Nidek Co Ltd 非接触式超音波眼圧計
JP2011092598A (ja) * 2009-10-30 2011-05-12 Nidek Co Ltd 非接触式超音波眼圧計
JP2011212124A (ja) * 2010-03-31 2011-10-27 Nidek Co Ltd 非接触式超音波眼圧計
US11406415B2 (en) 2012-06-11 2022-08-09 Tenex Health, Inc. Systems and methods for tissue treatment
JP2013031767A (ja) * 2012-11-19 2013-02-14 Nidek Co Ltd 非接触式超音波眼圧計
US11457937B2 (en) 2014-09-02 2022-10-04 Tenex Health, Inc. Subcutaneous wound debridement

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