DE102022113321A1 - Method and device for the non-contact, non-invasive displacement of an object, such as a lens, in relation to a body part, such as an eye - Google Patents

Abstract

A method and a device (1) for the non-contact, non-invasive displacement of an object (3), such as an intraocular lens (7), in relation to a body part (5), such as an eye (9), of a human or animal body is described. The method comprises: generating an acoustic pressure amplitude distribution (23) in a fluid (25), which is contained in the body part in a manipulation body volume (27) enclosing the object, by irradiating the manipulation body volume with ultrasound (21) produced by an ultrasound transducer arrangement (13 ) is emitted, and manipulating the ultrasonic transducer arrangement in such a way that the acoustic pressure amplitude distribution is modified with respect to at least one of its spatial arrangement and its spatial amplitude distribution, so that a force sufficient to displace the object is exerted locally on the object by the modified acoustic pressure amplitude distribution becomes.

Description

FIELD OF THE INVENTION

The present invention relates to a method and a device for the non-contact, non-invasive displacement of an object in relation to a body part of a human or animal body. In particular, the invention relates to a method and a device for the non-contact, non-invasive displacement of a lens, such as. B. an intraocular lens, in relation to a patient's eye.

TECHNICAL BACKGROUND

There are various medical and/or surgical applications in which one or more objects are to be positioned on or in a body part of a human or animal patient. The body part typically comprises a volume that is filled with a liquid and in which the object can float or on which the object can float. In a first step, the object can be introduced or implanted into the liquid volume. In a further step, the object can then be specifically relocated so that it is positioned and/or aligned in a desired configuration.

In the following, embodiments of the method described herein and/or the device described herein are explained primarily using an example in which the object to be relocated is a lens, in particular an artificial lens such as an intraocular lens, and in which the part of the body on which the lens is relocated is to be a patient's eye. It should be noted, however, that other embodiments of the method and/or apparatus described herein may relate to other types of objects, such as: B. a catheter or a medical implant that is used in other types of body parts, such as. B. a bladder, a blood vessel, etc., are to be relocated.

Using modern surgical methods, an artificial lens can be implanted into a patient's eye. In particular, an intraocular lens (IOL) may be implanted in the eye as part of treatment for cataracts or myopia. The lens is usually implanted during cataract surgery after the eye's natural lens has been removed.

IOL implantation can pose various risks, such as: B. the loss and/or unintentional rotation of the implanted lens after surgery. Particularly for multifocal IOLs, IOLs with extended depth of field and IOLs with astigmatism correction (collectively referred to as “premium IOLs”), correct placement and/or rotational alignment of the IOL in the eye is generally important, as incorrect placement of the lens can, among other things, affect the patient's vision can significantly affect.

Accordingly, in cases where a lens has been implanted into the eye in a first surgical procedure and the lens is then found to be misplaced and/or aligned, a second surgical procedure is usually required within a short period of time after the first surgical implantation procedure to correct lens placement and/or orientation. However, such a second surgical procedure is usually undesirable because, among other things, it requires additional effort and expense and also carries the risk of infection and/or damage to other parts of the eye.

SUMMARY OF THE INVENTION AND EMBODIMENTS

There may therefore be a need for an alternative method of non-contact, non-invasive displacement of an object with respect to a body part of a human or animal body, which makes it possible to avoid the above-mentioned second surgical procedure and thereby the problems associated with this second surgical procedure to overcome the associated disadvantages. Additionally, there may be a need for a device specifically configured to perform or control such a method. In particular, an approach may be required in which the position and/or orientation of an IOL can be manipulated from outside the body in a non-contact and non-invasive manner.

This need can be met with the subject matter of the independent claims. Advantageous embodiments are defined in the dependent claims and described in the following description and illustrated in the associated figures.

• (i) Erzeugen einer akustischen Druckamplitudenverteilung in einem Fluid, das sich in dem Körperteil befindet, in einem Manipulationskörpervolumen, das das Objekt enthält, durch Bestrahlen des Manipulationskörpervolumens mit Ultraschall, der von einer Ultraschallwandleranordnung emittiert wird, und
• (ii) Manipulieren der Ultraschallwandleranordnung in einer Weise, dass die akustische Druckamplitudenverteilung hinsichtlich ihrer räumlichen Anordnung und/oder ihrer räumlichen Amplitudenverteilung modifiziert wird, so dass durch die modifizierte akustische Druckamplitudenverteilung lokal eine zum Verlagern des Objekts ausreichende Kraft auf das Objekt ausgeübt wird.

According to a first aspect of the present invention, a method for non-contact, non-invasive displacement of an object in relation to a body part of a human or animal body is presented. The procedure includes at least the following steps, preferably in the order given:

• (i) generating an acoustic pressure amplitude distribution in a fluid located in the body part in a manipulation body volume containing the object by irradiating the manipulation body volume with ultrasound emitted by an ultrasound transducer arrangement, and
• (ii) manipulating the ultrasonic transducer arrangement in such a way that the acoustic pressure amplitude distribution is modified with regard to its spatial arrangement and/or its spatial amplitude distribution, so that a force sufficient to displace the object is locally exerted on the object by the modified acoustic pressure amplitude distribution.

According to a second aspect of the invention, a device for the non-contact, non-invasive displacement of an object in relation to a body part of a human or animal body is presented. The device comprises at least one ultrasonic transducer arrangement and a controller for controlling the ultrasonic transducer arrangement. The controller and the ultrasonic transducer arrangement are designed to carry out and/or control the method according to an embodiment of the first aspect of the invention.

• Es wird hier vorgeschlagen, akustische Kräfte zu verwenden, um dadurch die Position und/oder Orientierung eines Objekts relativ zu einem Körperteil von außerhalb des Körpers eines Patienten zu manipulieren. Dabei werden die akustischen Kräfte unter Verwendung von Ultraschall erzeugt, der von einer Ultraschallwandleranordnung (=Ultraschallwandler-Array) in einer solchen spezifischen Weise ausgesendet wird, dass eine akustische Druckamplitudenverteilung (PAD - pressure amplitude distribution) innerhalb eines in dem Körperteil enthaltenen Fluids erzeugt wird und dann die Erzeugung der akustischen PAD gezielt so manipuliert wird, dass ihre räumliche Anordnung und/oder ihre räumliche Amplitudenverteilung in einer beabsichtigten Weise modifiziert wird. Insbesondere wird die Erzeugung des Ultraschalls durch der Ultraschallwandleranordnung so manipuliert, dass durch die Veränderung der akustischen PAD eine auf das Objekt wirkende Kraft erzeugt wird, die ausreichend stark und geeignet gerichtet ist, das Objekt in einer beabsichtigten Weise zu verlagern.

Briefly summarized and without limiting the scope of the invention, basic ideas underlying the embodiments of the invention and associated possible advantages are roughly described as follows:

• It is proposed herein to use acoustic forces to thereby manipulate the position and/or orientation of an object relative to a body part from outside a patient's body. The acoustic forces are generated using ultrasound, which is emitted by an ultrasound transducer arrangement (=ultrasound transducer array) in such a specific way that an acoustic pressure amplitude distribution (PAD - pressure amplitude distribution) is generated within a fluid contained in the body part and then the generation of the acoustic PAD is specifically manipulated in such a way that its spatial arrangement and/or its spatial amplitude distribution is modified in an intended manner. In particular, the generation of the ultrasound by the ultrasound transducer arrangement is manipulated such that the change in the acoustic PAD generates a force acting on the object that is sufficiently strong and appropriately directed to displace the object in an intended manner.

In fact, the use of ultrasound is known for various medical and/or surgical applications. This is how it is done FR 2211207 B1 described an ultrasound instrument for eye surgery. DE 19623213 A1 describes an eye surgical instrument for shattering the lenses of the eye using ultrasound. EP 617599 B1 discloses an ultrasound therapy device that emits ultrasound waves with thermal and cavitative effects. US 7178530 B2 discloses a method for improving the visually impaired effects of cataracts and the like. EP 2996649 A1 discloses a non-contact user interface for ophthalmic devices. WO 2016/131055 A1 discloses systems and methods for monitoring eye health. CA 2213648 A1 discloses a device for monitoring fluid loss in the eye. US 3990452 A discloses a medical device for performing operations and treatments using ultrasound energy. EP 2512599 B1 discloses a device for ultrasound treatment. Finally describes the WO 2017/161348 A1 Methods and a device for the effective positioning of eye lenses.

Conventional methods for positioning and/or aligning an artificial lens in an eye generally rely on invasive repositioning of the lens by inserting a surgical instrument into the eye.

Another approach relies on targeted, non-invasive focusing of energy, including high-intensity focused ultrasound (HIFU), inside the eye to alter the properties or location of the natural human lens in the eye. In the WO 2017/161348 A1 For example, methods and a device are described with which an effective lens position of the eye can be adjusted in order to correct a refractive error of the eye. The procedures and device can be designed to apply energy to the sclera and other areas of the eye to adjust the eye's effective lens position for distance vision. The sclera may be treated to shrink or relax the sclera, and combinations thereof, to correct the position of the eye's lens to improve vision related to a refractive error of the eye. A target position of the lens can be determined to correct the refractive error of the eye, and the energy can be applied to move the lens toward the target position.

However, the latter approaches rely on mechanisms that are fundamentally different from those used in the approach described here. Specifically, the conventional approaches use focused energy to produce an intended change in the tissue, that is, to cause an intended type of injury, e.g. B. through local excessive heating and later scarring, e.g. b. the sclera and/or associated structures. The displacement and/or realignment of the lens is generally caused by the scarring.

However, the response to injury in living tissue has been found to be generally non-linear and potentially unpredictable. In addition, the effects caused by HIFU treatment usually only appear a certain time after the treatment has been completed, as the healing process, for example, requires a certain amount of time. In other words, a response to treatment usually occurs after a certain delay. Accordingly, there is no way to directly influence treatment by observing treatment results. Instead, unintended treatment results can only be identified after treatment has been completed and, if necessary, corrected through further treatment.

In addition, for example, the one in the WO 2017/161348 A1 The approach described is limited to the front-to-back movement of a capsular bag and its contents (i.e., either a native human lens or an artificial lens) and generally does not provide the ability to rotate or relocate an independent structure (such as an IOL) anywhere in the eye .

In order to overcome, among other things, the shortcomings of conventional approaches, a fundamentally different approach is described here. In this approach, the ultrasound emitted by an ultrasonic transducer assembly is selectively used to generate an acoustic pressure amplitude distribution (PAD) in a fluid located in the part of the body in which an object is being displaced within a volume, referred to herein as a “manipulation body volume”. and/or should be aligned.

This takes advantage of the fact that ultrasound can be emitted specifically with high intensity and with a macroscopically inhomogeneous intensity distribution, so that the irradiated ultrasound creates an acoustic PAD with areas of higher pressure and areas of lower pressure within the liquid in the manipulation body volume. The PAD can then be specifically positioned relative to the object to be moved and the ultrasound transducer arrangement can be specifically manipulated so that the PAD's spatial arrangement and/or spatial amplitude distribution is changed. The modification can be brought about in such a way that forces are exerted on the object that are strong enough to displace and/or rotate the object in the desired direction.

While in conventional approaches forces on an object are only generated indirectly, e.g. through the induction of local injuries and subsequent scarring, in the approach described here forces are generated directly on the object through the specifically controlled and manipulated generation of the acoustic PAD.

Since the forces are generated directly and can therefore directly affect the positioning of the object to be displaced, the process of displacing the object can be precisely controlled during the displacement treatment. In addition, no local injuries need to be caused in living tissue, which means, among other things, the risks resulting from such injuries can be avoided.

It should be noted that the inventor of the present application has described in previous patent applications ways of generating a pressure amplitude distribution for the manipulation of objects in other, non-medical devices. That's how it describes WO 2022/002825 A1 the contactless manipulation of objects using controlled electroacoustic transducers. WO 2022/058281 A1 discloses a method for handling an object in a pressure amplitude distribution. Although these prior patent applications relate to non-medical devices and do not specifically teach the displacement of an object with respect to a body part, features and/or details of the approaches described in these prior patent applications may apply to embodiments of the method and apparatus described herein transferred and/or adapted. Accordingly, the entire contents of these prior patent applications are incorporated herein by reference.

Possible features of embodiments of the invention and associated possible advantages are described in more detail below.

The method and device described herein can be designed so that small objects can be displaced with respect to a body part in a human or animal body. The term “displacement” can be understood as translocation, displacement, movement, rotation, rotation, etc., i.e. H. as a movement in which a location and/or orientation of the object is changed. In particular, the object can be displaced within the patient's body or the object can be translocated from outside the patient's body into the patient's body.

The object can have a small size of e.g. B. less than 5 cm, preferably less than 2 cm, less than 1 cm or even less than 5 mm in a maximum direction of extension. However, the objects can have a macroscopic size of e.g. B. have more than 0.5 mm, preferably more than 1 mm, more than 2 mm or even more than 4 mm. The object may have a flat shape, that is, a quasi-two-dimensional shape. The thickness of the object can be, for example, less than 5 mm, preferably less than 2 mm or even less than 1 mm. The item may be light in weight, e.g. B. a weight in the range of milligrams to a few grams, e.g. B. between 1 mg and 10 g, preferably between 10 mg and 1 g.

The body part can be any body part on or in which the object is to be placed. The body part is generally contained within a living organism. Generally, the body part includes a liquid in or on which the object can be placed. The fluid can be a liquid. The fluid may have a low viscosity corresponding to the viscosity of water, the viscosity of oil, the viscosity of a water solution, or the viscosity of a water emulsion. The liquid can be contained in a volume of the manipulation body in which the object is to be moved. The liquid can, for example, fill a cavity in the body part. The cavity can form the volume of the manipulation body. The cavity may be surrounded by living tissue such as skin, membrane, muscles, etc. Alternatively or additionally, the liquid can be contained in a volume of the manipulation body that is formed by a liquid film. In a specific example, the fluid may be a fluid contained in a capsular bag of a patient's eye. Alternatively, the liquid can be provided as a liquid film, for example as a tear fluid film, on the patient's eye. As further alternatives, the liquid may be urine in a patient's bladder or blood in a patient's blood vessel. The volume of the manipulation body containing the liquid can range from a few microliters to several milliliters, e.g. B. between 1 µ1 and 100 ml, preferably between 10 µ1 and 10 ml.

The objects can be arranged so that they float in or float on the liquid contained in the volume of the manipulation body. Due to the low viscosity of the fluid and the small size and mass of the object, the object can be displaced and/or reoriented when relatively small forces are applied. Such forces can be, for example, less than 1 N, preferably less than 0.1 N, less than 10 mN or even less than 1 mN. In particular, the forces can be between 0.1 mN and 0.1 N, preferably between 1 mN and 30 mN.

The forces required to displace the object are generated by exposing the object to an acoustic pressure amplitude distribution (PAD), which is generated by sonicating the manipulation body volume with ultrasound. It should be noted that the PAD can also be created in volumes that are adjacent to the manipulation body volume inside or outside the patient's body, i.e. H. for example, in a coupling fluid provided near the patient's eye. The ultrasound can have frequencies above 20 kHz, e.g. B. in a range between 20 kHz and 2 MHz, preferably between 20 kHz and 200 kHz, more preferably between 30 kHz and 150 kHz. The ultrasound can be emitted with high intensity. In particular, an acoustic overpressure can be in the kPa range compared to the environment, e.g. B. in an air-filled volume in many cases below 50 kPa or even below 10 kPa.

The ultrasound is emitted by an ultrasound transducer arrangement. As described in more detail below, the ultrasonic transducer assembly may include one or more ultrasonic generators (sometimes referred to as electroacoustic transducers) and optionally one or more acoustic lenses. The operation of the ultrasonic transducer arrangement can be controlled by a control device.

By appropriately irradiating ultrasound, an intended PAD can be generated in the volume of the manipulation body. The ultrasonic waves can be emitted by one or preferably several ultrasonic generators. The ultrasound generators can be arranged at different locations and/or oriented in different directions. Optionally, the ultrasound emitted by the ultrasound generators can be focused or deflected using acoustic lenses. In addition, surfaces or interfaces can be present on which at least part of the emitted ultrasound is reflected. Accordingly, ultrasonic waves that are emitted by different ultrasonic generators and/or reflected on different surfaces or interfaces can superimpose and interfere. As a result, ultrasonic standing waves and/or beats of ultrasonic waves can be generated, which can result in a stationary or quasi-stationary PAD (i.e., a PAD in which the pressure amplitude distribution changes at a frequency that is many orders of magnitude smaller as the frequency of the ultrasound). In such a PAD, the pressure distribution is generally inhomogeneous, ie the local pressures can vary, with partial volumes having higher pressures than neighboring partial volumes. Due to the inhomogeneous pressure distribution, pressure gradients occur within the PAD. As a result of this inhomogeneous pressure distribution and the pressure gradients, forces can act on an object in the manipulation body volume when it is exposed to the PAD. These forces act in particular in a direction that corresponds to the pressure gradient that is effective at a specific point on the object to be moved.

In order to displace the object within the manipulation body volume in an intended manner, the acoustic PAD is specifically modified by appropriate manipulation of the ultrasonic transducer assembly. In other words, the object is moved by sequentially generating at least two PADs, of which an initial PAD may correspond to an initial state of the object and an end PAD may correspond to a target state of the object. In particular, the object can e.g. B. be “trapped” in one or more low pressure areas of the respective PAD. When the PAD is manipulated, the object generally follows that manipulation.

In particular, the PAD is changed in its spatial arrangement and/or its spatial amplitude distribution. In other words, the location at which the PAD is created within the manipulation body volume can be intentionally shifted by appropriate manipulation of the ultrasonic transducer assembly. For this purpose, the entire ultrasonic transducer arrangement or parts thereof can be moved in a suitable manner. Additionally or alternatively, individual ultrasound generators and/or acoustic lenses or other components of the ultrasound transducer arrangement can be moved with respect to other components of the ultrasound transducer arrangement. As a further addition or alternative, the operation of one or more ultrasound generators and/or acoustic lenses and/or other components contained in the ultrasound transducer arrangement can be specifically manipulated in such a way that an amplitude and/or a phase of the ultrasound emitted by them is changed . As a result of one or a combination of all of these measures, the spatial arrangement and/or the spatial amplitude distribution of the PAD can be changed to create pressure gradients that result in significant forces acting on the object in an intended direction. In response to these forces, the object may be precisely displaced within the volume of the manipulation body to locate it in an intended position and/or orientation with respect to the body part.

According to one embodiment, the ultrasound is emitted at an energy density that is sufficiently low to avoid tissue damage, scarring, muscle relaxation, muscle tension, acoustic currents and/or cavitation within the manipulation body volume.

In other words, while the ultrasound is generated and emitted by the ultrasound transducer assembly with sufficient intensity to generate significant forces for the movement of the object to be displaced, the energy density of this ultrasound must be limited to a level at which living tissue is not injured and no activation of the muscles is influenced by the emitted ultrasound. In addition, the energy density of the ultrasound must be low enough to avoid acoustic currents and cavitation. Acoustic flow is a uniform flow in a liquid caused by the absorption of high-amplitude acoustic vibrations. The maximum and minimum values (amplitude) of the PAD are chosen to prevent acoustic currents. Cavitation is the formation of small, vapor-filled cavities in the liquid. This is caused by the static pressure of a liquid falling below the vapor pressure of the liquid. The pressure gradients of the PAD are chosen to prevent cavitation. In particular, the pressure amplitude of the low-pressure areas within the PAD is chosen to be sufficiently high to prevent cavitation.

Accordingly, the ultrasound must be emitted by the ultrasound transducer assembly at an intensity sufficiently high to produce the PAD in order to generate sufficient forces acting directly on the object to displace it, but the ultrasound intensity must be limited to values which are low enough to prevent secondary effects resulting from the tissue being irreversibly altered by the absorption of the ultrasound energy, i.e. H. for example, to avoid injuries or scarring of living tissue.

According to one embodiment, the sound pressure amplitude distribution is generated with at least a first pressure range with a lower sound pressure and at least a second pressure range with a higher sound pressure, with a size and/or a geometry and/or an amplitude of the first and second pressure ranges being dependent ability of position and/or geometric features of the object is set.

In other words, the PAD can be created such that it contains first and second pressure regions that differ significantly in terms of the sound pressure prevailing in the respective regions. The ultrasound transducer arrangement can be configured and/or operated in such a way that the size and/or the geometry of the first and second pressure regions takes into account positional properties of the object, i.e. where the object is arranged in relation to the body part, and/or taking into account geometric properties of the object, i.e. what dimensions and/or shape the object has, is specifically adapted. For example, the larger the object is, the larger the size of the first and/or second print area can be set. By appropriately adjusting the size and/or geometry of the first and second pressure areas, the effect of the forces exerted by the PAD on the object can be optimized.

According to a further embodiment, the sound pressure amplitude distribution is generated such that the object is predominantly in the first pressure range with lower sound pressure and is inserted between at least two second pressure ranges with higher sound pressure.

In other words, the PAD may be created with two second, higher sound pressure ranges that include a first, lower sound pressure range therebetween. The PAD can then be arranged and the sizes and/or geometries of the first and second print areas can be adjusted so that the object is completely contained in the first print area or at least a predominant part of the object is contained in the first print area. Accordingly, the second pressure areas of higher sound pressure are located on opposite sides of the object and “pinch” the object between these higher pressure areas. The PAD can act similarly to non-contact pliers to grasp and possibly move the object.

According to one embodiment, the ultrasound is emitted such that it has a wavelength in the volume of the manipulation body that is between 100% and 400%, preferably between 150% and 300%, of the lateral dimensions of the object in an irradiation direction of the emitted ultrasound.

In general, ultrasound is performed at a frequency in the ultrasonic range, i.e. H. over 20 kHz, radiated. The dimensions of the pressure fluctuations within the PAD usually depend on the wavelength of the irradiated ultrasound. To enable effective detection of an object with the PAD, the dimensions of a first low-pressure region should be similar to or equal to half the wavelength of the irradiated ultrasound. In other words: To create an object with a width w of z. B. to be able to clamp a few millimeters, the wavelength of the irradiated ultrasound should be such that half of the wavelength λ/2 is of a similar order of magnitude as the dimensions of the object, i.e. H. half the wavelength λ/2 should be approximately 1 to 2 times the lateral dimensions of the object. Accordingly, for an object with a width of, for example, 6 mm, the wavelength λ of the ultrasound that generates the PAD should be in a range of 12 to 24 mm.

In general, the wavelength λ depends on the properties, in particular on the speed of sound, of the liquid into which the ultrasound is irradiated. For example, the speed of sound c in water is about 1500 m/s. Accordingly, a frequency f of the ultrasound that generates the PAD can be adjusted to satisfy f = c / λ = c / (2 * 1.5 * w), perhaps with a tolerance of about ± 50%. At c = 1500 m/s and w = 6 mm this results in a preferred frequency range of 83 kHz ± 41.5 kHz.

In one embodiment, the pressure amplitude distribution is generated such that the object is completely enclosed.

In other words: Although it is in principle possible that the volume in which the acoustic PAD is generated does not completely enclose the entire object to be relocated, it is considered advantageous if the volume encloses the entire object. In such a configuration, every part of the object is in the liquid contained in the volume enclosing the PAD, so that the entire object can float or float freely and is therefore easy to relocate.

In one embodiment, the volume of the manipulation body is determined such that its dimensions are at most three times, preferably at most twice, the dimensions of the object.

In other words: The volume of the manipulation body including the PAD preferably extends in the immediate vicinity of the object to be moved, but does not necessarily have to extend far beyond the contour of the object. By limiting the dimensions of the mani pulsation body volume on such a close range, various advantageous effects can be achieved, such as. B. limiting energy consumption for ultrasound generation, limiting side effects to body parts distant from the object, etc.

In one embodiment, the ultrasound transducer arrangement is manipulated such that the sound pressure amplitude distribution is laterally shifted and/or rotated within a plane that crosses an emission direction of the ultrasound.

More specifically, in order to generate the force to displace the object, the PAD and in particular its spatial arrangement and/or its spatial amplitude distribution can be manipulated so that they are displaced in the plane that crosses the emission direction of the ultrasound. This plane can preferably be orthogonal to the radiation direction. The radiation direction can be a direction of propagation of the ultrasound, i.e. H. one direction of irradiation. The plane may extend along a surface or interface of the body part where the object is to be displaced. Accordingly, the object can be moved and/or rotated along such a body part surface/interface using the method proposed here.

According to one embodiment, a liquid coupling medium is arranged between the manipulation body volume and the ultrasonic transducer arrangement, which has acoustic properties that correspond to the acoustic properties of the liquid surrounding the object in the manipulation body volume with a tolerance of ± 50%.

In other words: It has proven to be advantageous to fill the entire space between a liquid surface that encloses the object to be moved, on the one hand, and a surface of the ultrasonic transducer arrangement, which emits the ultrasound to generate the PAD, with a liquid coupling medium, on the other hand. This coupling medium can be a fluid such as a liquid, a gel or the like. In particular, such a coupling medium should have acoustic properties such as a speed of sound that corresponds to or is similar to the acoustic properties of the fluid in the volume of the manipulation body. The acoustic properties of the fluid coupling medium are preferably in a range between 50% and 150% of those of the fluid in the volume of the manipulation body. For example, if the fluid in the volume of the manipulation body has a sound speed c1, the fluid coupling medium must have a sound speed c2 = c1 ± 0.5*c1. The tolerance can preferably be less than 50%, i.e. for example 30%, 20% or 10%. This allows the ultrasound generated at the ultrasonic transducer arrangement to be easily transmitted to the fluid in the manipulation body volume and, in particular, to prevent significant portions of the ultrasound from being reflected at interfaces that would occur without the fluid coupling medium at transitions between the fluid in the manipulation body volume and, for example, a gas-filled volume adjacent to it .

According to one embodiment, the ultrasound transducer arrangement is mechanically attached to the body part that includes the manipulation body volume during the generation of the ultrasound.

Due to this fixation, the ultrasound transducer arrangement may not move relative to the part of the body on which the object is to be displaced. So can e.g. B. an eye in which a lens is to be relocated can be stabilized during the displacement process due to its fixation relative to the ultrasound transducer arrangement.

According to one embodiment, the object is a lens, in particular an intraocular lens, and the manipulation body volume is arranged on an eye of a patient.

As explained in more detail here, the method and device described here can be particularly advantageous for the displacement and/or rotation of an artificial lens within a manipulation body volume that is located in a patient's eye. The method can be used, for example, if the lens was implanted in a capsular bag in the eye in a first surgical procedure, but then became dislocated and/or disoriented, i.e. H. has been moved and/or rotated from its desired position and/or orientation. With the proposed method, the lens can then be rearranged and/or aligned in a non-contact, non-invasive displacement procedure so that a second surgical procedure can be avoided.

According to an embodiment of the displacement device according to the second aspect of the invention, the ultrasound transducer arrangement comprises at least two ultrasound generators which are arranged laterally next to one another. The control device is set up to individually control the operation of each of the ultrasound generators independently of the other ultrasound generator in such a way that a pattern of the ultrasound generated by the ultrasound transducer arrangement in one is shifted in a lateral direction and/or in a depth direction.

In other words, the ultrasonic transducer arrangement can preferably comprise a plurality of ultrasonic generators. Each ultrasonic generator can work independently of the others. Accordingly, each ultrasound generator can emit ultrasound with an individual frequency, amplitude and/or phase. The ultrasound generators can be arranged next to each other. Adjacent ultrasound generators can abut one another directly or be spaced apart from one another. Preferably, the ultrasound generators of the ultrasound transducer arrangement can be arranged along a common surface. This common surface can be flat or curved. In particular, such a common surface can run essentially parallel to a plane or a curved surface in which the object is to be displaced in relation to the body part.

With such a configuration of the ultrasonic transducer arrangement, the control unit can individually control the operation of each individual ultrasonic generator or subgroups of ultrasonic generators independently of other ultrasonic generators. Through such individual control of the ultrasound generators, a pattern with which the ultrasound is generated by the ultrasound transducer arrangement can be influenced. Such an ultrasonic pattern generally affects the characteristics of the acoustic PAD such as its spatial arrangement and/or its spatial amplitude distribution.

In particular, the ultrasound pattern can be influenced in a controlled manner so that it is displaced in a lateral direction along a plane that crosses the emission direction of the ultrasound and/or in a depth direction perpendicular to this lateral direction. Accordingly, through appropriate control of the multiple ultrasound generators, the ultrasound pattern can be influenced such that the resulting changes in the PAD result in the generation of forces acting on the object to displace the object in the intended manner.

In such an implementation, the ultrasonic transducer assembly or its ultrasonic generators or other components do not necessarily need to move themselves to displace the object via induced changes in the PAD. Instead, such changes in the PAD can only be achieved by appropriately controlling the individual ultrasound generators, e.g. B. in terms of the amplitude and / or phase of the ultrasound they generate. As a rule, no moving parts are required in the ultrasonic transducer arrangement.

According to one embodiment, the ultrasonic transducer assembly includes at least one acoustic lens, wherein the controller is configured to control the at least one acoustic lens to shift a pattern of the ultrasound generated by the ultrasonic transducer assembly in a lateral direction and/or in a depth direction.

In other words: Instead of or in addition to influencing the ultrasound pattern generated by the ultrasound transducer arrangement by controlling the individual ultrasound generators, as described in the previous paragraph, such an ultrasound pattern can also be influenced by suitable control of one or more acoustic lenses contained in the ultrasound transducer arrangement. These acoustic lenses can be configured to focus, diverge and/or redirect the ultrasound transmitted through them. The acoustic lens (s) can be controlled by the control unit of the displacement device with regard to their acoustic properties, whereby the ultrasound transmission through the individual acoustic lens is influenced, and / or with respect to a spatial arrangement of each individual or multiple acoustic lenses, whereby the ultrasound transmission is influenced by the entire acoustic lens arrangement. In particular, the one or more acoustic lenses can be selectively controlled to alter the ultrasound pattern such that the resulting PAD exerts forces on the object in the manipulation body volume to displace the object in an intended manner.

According to one embodiment, the displacement device further comprises a displacement mechanism configured to mechanically displace at least one component included in the ultrasonic transducer assembly such that a pattern of ultrasound generated by the ultrasonic transducer assembly is displaced in a lateral direction and/or a depth direction.

Alternatively or in addition to the possibilities described above for influencing the ultrasound pattern by appropriately controlling the operation of the one or more ultrasound generators and/or acoustic lenses, the displacement device can therefore comprise a specific displacement mechanism with which the positioning of the components contained in the ultrasound transducer arrangement can be influenced . With such a component or Several components can be any component that influences the ultrasound generation and/or the ultrasound propagation within the ultrasound transducer arrangement. Such a component can be, for example, one of the ultrasound generators, one of the acoustic lenses, an acoustic reflector, an acoustic deflector, an acoustic absorber or the like. The displacement mechanism may include one or more actuators. The actuators can work electromechanically, pneumatically, hydraulically, etc. The displacement mechanism may be configured to displace the at least one component included in the ultrasonic transducer assembly along a linear or curved path.

By controlled displacement of one or more such components, the ultrasound pattern generated by the ultrasonic transducer assembly can be influenced in the intended manner, so that the resulting change in the PAD results in appropriate forces being exerted on the object to be displaced in the intended manner.

Optionally, the displacement device can include a fixation mechanism for fixing the ultrasound transducer arrangement relative to the part of the body in which the object is to be displaced. The relocalization device can, for example, comprise a suction unit, via which a negative pressure can be generated between the body part and the ultrasonic transducer arrangement, whereby the ultrasonic transducer arrangement z. B. is sucked onto the surface of an eye in which a lens is to be relocated.

It should be noted that possible features and advantages of embodiments of the invention are described herein partly with respect to a method for non-contact displacing an object relative to a body part and partly with respect to a device for carrying out such a method. Those skilled in the art will recognize that features can be appropriately transferred from one embodiment to another and features can be modified, adapted, combined and/or replaced, etc., to achieve further embodiments of the invention.

BRIEF DESCRIPTION OF DRAWINGS

• 1 zeigt eine Vorrichtung zum Verlagern Intraokularlinse in einem Auge eines Patienten gemäß einer Ausführungsform der vorliegenden Erfindung.
• , (b) zeigen eine Draufsicht und eine Seitenansicht einer Intraokularlinse.
• , (b) zeigen Draufsichten auf eine Intraokularlinse, die in einer Druckamplitudenverteilung in einer im Auge des Patienten enthaltenen Flüssigkeit in einer ersten Konfiguration und in einer zweiten Konfiguration angeordnet ist.

Advantageous embodiments of the invention are described below with reference to the accompanying drawings. However, neither the drawings nor the description should be construed as limiting the invention.

• 1 shows a device for displacing intraocular lens in a patient's eye according to an embodiment of the present invention.
• , (b) show a top view and a side view of an intraocular lens.
• , (b) show top views of an intraocular lens arranged in a pressure amplitude distribution in a fluid contained in the patient's eye in a first configuration and in a second configuration.

The illustrations are only schematic and not to scale. The same reference numbers refer to the same or similar features.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

1 shows a device 1 for the contactless, non-invasive displacement of an object 3 in relation to a body part 5 of a human or animal body. In the example shown, the object 3 is an intraocular lens 7 and the body part is an eye 9. In particular, the IOL 7 should be displaced and/or realigned within a capsular bag 11 in the eye 9.

As in 2(a) and 2 B) Illustrated in a top view and a side view, respectively, the IOL 7 includes a circular central lens body 71 and two projections 73 or legs that extend radially from a circumference of the central lens body 71. The projections 73 can serve to fix the IOL 7 at an intended location and/or in an intended orientation within the capsular bag 11 in the eye 9.

The displacement device 1 comprises an ultrasonic transducer arrangement 13 and a control unit 15 for controlling the ultrasonic transducer arrangement 13. The ultrasonic transducer arrangement 13 comprises a plurality of ultrasound generators 17. The ultrasonic transducer arrangement 13 also comprises a plurality of acoustic lenses 19. The ultrasonic generators 17 and the acoustic lenses 19 are in a two-dimensional pattern along a curved surface arranged, which runs essentially parallel to an outer surface of the eye 9. Accordingly, the ultrasound generators 17 and the acoustic lenses 19 are arranged so that each of the ultrasound generators 17 can emit the ultrasound 21 in an irradiation direction in the direction of the IOL 7 in the capsular bag 11, while the ultrasound 21 is transmitted through an associated one of the acoustic lenses 19 and thereby e.g . B. can be focused and/or distracted.

The ultrasonic transducer arrangement 13 is suitable for specifically generating an acoustic pressure amplitude distribution (PAD) 23 in a fluid 25 that is contained in the body part 5 in a manipulation body volume 27. In the present example, the liquid 25 is contained in the capsular bag 11, ie the PAD 23 is created so that it extends at least partially over the internal volume of the capsular bag 11. In such a manipulation body volume 27 in the liquid-filled capsular bag 11, the IOL 7 can float or float in such a way that it can be easily displaced and/or rotated in the lateral direction and/or in the depth direction with relatively low forces.

As in shown in a top view, such forces (indicated by small arrows) can be generated by generating the acoustic PAD 23 in a first processing step so that it “clamps” the IOL 7. For this purpose, the ultrasonic transducer arrangement 13 can emit ultrasound 21 with such a pattern that the generated PAD 23 comprises at least a first pressure area 29 with lower sound pressure and, for example, two second pressure areas 31 with higher sound pressure. The frequency of the ultrasound sound 21, which is used to generate the PAD 23, can be adjusted so that half λ/2 of the wavelength λ of the ultrasound sound 21 is the same or similar to the lateral dimensions of the IOL 7, e.g. B. their width. Accordingly, the generated PAD 23 can be arranged so that the IOL 7 lies within the first pressure area 29 with lower sound pressure and is enclosed on its two opposite sides by the second pressure areas 31 with higher sound pressure. In particular, the projections 73 of the IOL 7 can be approximately along a linear line (in 3(a) oriented in the y direction), which represents the first pressure area 29 with low pressure.

Then, as in 3(b) shown, in a second processing step the ultrasound transducer arrangement 13 is manipulated so that the PAD 23 is modified with regard to its spatial arrangement and/or its spatial amplitude distribution. In particular, the PAD 23 is changed so that the ultrasound pattern produces the first low-pressure region 29 and the adjacent second high-pressure regions 31 in a configuration rotated by 90° compared to the configuration in the first processing step. Such a rotation of the PAD 23 also rotates the IOL 7 clamped by the PAD 23 through an angle of 90°. Accordingly, the PAD 23 can be modified by appropriate manipulation of the ultrasound transducer assembly 13 to generate forces sufficient to displace the IOL 7 to an intended position and/or orientation.

To modify the PAD 23, the control unit 15 may individually control the operation of each of the ultrasonic generators 17 independently of the other ultrasonic generators 17 so that the ultrasonic pattern 21 generated by the ultrasonic transducer assembly 13 is shifted in a lateral direction, i.e. H. is moved in a linear and/or rotational movement within an xy plane orthogonal to a z direction corresponding to the direction of ultrasound radiation. Alternatively or additionally, the ultrasound generators 17 can be operated in such a way that the ultrasound pattern 21 generated by the ultrasound transducer arrangement 13 is shifted in a depth direction, i.e. H. is moved in the z direction.

In addition, the control device 15 can control the acoustic lenses 17 so that the ultrasound pattern 21 generated by the ultrasound transducer arrangement 13 is shifted in a lateral direction and/or in a depth direction.

As a further alternative or addition, the propagation device 1 includes a displacement mechanism 33. This displacement mechanism 33 can be at least one of the components, i.e. H. one of the ultrasound generators 17, one of the acoustic lenses 19 and / or one of an optional variety of other components, so that the ultrasound pattern 21 generated by the ultrasound transducer arrangement 13 is displaced laterally or in the depth direction.

Accordingly, in the best case scenario, the ultrasound transducer arrangement 13 can be operated in such a way that the PAD 23 is modified in such a way that forces are generated which cause the IOL 7 to move in six degrees of freedom, i.e. H. can be precisely moved along the three orthogonal directions x, y, z and/or around three orthogonal axes of rotation.

In addition to the implementation of the IOL in a capsular bag described above, the method proposed here can also be used to support the initial implantation of an IOL (or a prosthesis or a body part) by moving the object in question from outside the body to inside the body. This can contribute to greater automation of a surgical procedure.

To improve ultrasound transmission, a liquid or gel serving as a liquid coupling medium 35 is placed between the ultrasound transducer assembly 13 and an outer surface of the eye 9. The liquid coupling medium 35 has similar acoustics Properties like the liquid 25 in the capsular bag 11.

Alternatively or additionally, the displacement device 1 can have a fixation mechanism 37, via which the ultrasound transducer arrangement 13 can be temporarily mechanically fixed to the body part including the manipulation body volume 27. In eye surgery, the fixation mechanism 37 can be designed, for example, with sealing lips 41 and a (only very schematically indicated) suction unit 39, which can generate a negative pressure between the ultrasound transducer arrangement 13 and an outer surface of the eye 9. This allows the eye 9 to be stabilized if, for example, the displacement device 1 is used to support a cataract/IOL operation.

• Um die Nachteile des Standes der Technik zu überwinden, verwenden die Ausführungsformen der Erfindung akustische Druckamplitudenverteilungen, um ein Objekt innerhalb des Körpers auf direkte, nicht-invasive Weise zu manipulieren.

Finally, possible implementations and features of embodiments of the methods and devices described here are described with a slightly modified wording as follows:

• To overcome the disadvantages of the prior art, embodiments of the invention use acoustic pressure amplitude distributions to manipulate an object within the body in a direct, non-invasive manner.

A pressure amplitude distribution (PAD) is generated within the body using at least one, preferably several, electroacoustic transducers located outside the body. The array of transducers may also include at least one acoustic lens to focus or manipulate the acoustic PAD in a desired manner. This arrangement is also known as a transducer array.

The transducer arrangement is preferably coupled to the body via a coupling medium, preferably a liquid or a gel. The coupling medium preferably has similar acoustic properties to the body to enable good transmission of the acoustic energy/PAD into the body with low losses and heating. The coupling medium can also be used to control the temperature (particularly cooling) of the body during the procedure.

The PAD includes areas of high and low sound pressure. In particular, the PAD comprises at least one, preferably at least two, areas with high sound pressure. The PAD is generated depending on certain characteristics of the object to be moved, in particular depending on its size, its position in the body (and the resulting distance from the transducer arrangement), its orientation, the acoustic properties of its material, etc.

The PAD is created directly on/in the environment of the object to be manipulated in order to achieve direct manipulation. Direct manipulation means that the (acoustic) forces resulting from the PAD (more precisely its local gradients) act in the immediate vicinity or directly on the body to be manipulated. In other words, the manipulation is not based (at least not primarily) on “secondary effects” such as tissue damage/scarring, muscle relaxation and/or tension, acoustic flow, cavitation, etc. The acoustic energy is maintained at a level sufficiently low to to limit losses/heating below critical levels (i.e. levels at which significant cell or tissue damage would occur) and to prevent cavitation.

Manipulation means the displacement and/or rotation of the object in any plane and/or around any axis. The manipulation is achieved by sequentially generating at least two PADs, of which an initial PAD corresponds to the initial state of the object and a final PAD corresponds to the target state of the object. The object is “trapped” in the low pressure areas of the respective PAD. If the PAD is manipulated, the object follows this manipulation.

An exemplary embodiment for rotating an IOL inside the eye is considered. shows schematic top and side views of an IOL and the coordinate system introduced. shows a side view of the embodiment in which the IOL is already implanted in the capsular bag of the eye. The transducer array, consisting of several individual electroacoustic transducers, is placed above the eye and aligned so that the acoustic energy (sound waves) is radiated towards the eye. The transducer array is coupled to the eye via a coupling medium. A schematic representation of the generated PAD in a vertical plane is shown. It consists of two adjacent high pressure areas in the immediate vicinity of the IOL.

The rotation of the IOL in the eye is considered here as an example. shows a top view of the IOL to be rotated and the surrounding PAD in a horizontal plane. The forces resulting from the PAD are symbolized by the small arrows. The magnitude of these forces depends on the local gradients of the PAD and can be adjusted by adjusting the acoustic power supplied to the transducer array. In is located IOL in its original angular position about its optical axis (an axis passing through the center of rotation of the IOL parallel to the z-axis) and is surrounded by the first PAD. To rotate the IOL, the PAD is rotated clockwise to transmit torque to the IOL. shows the IOL in its final angular position, rotated 90° clockwise and surrounded by the final PAD. The PAD is carried out in several intermediate steps, e.g. B. rotated in 10° increments before reaching the final PAD.

Similarly, the PAD can be moved horizontally to achieve horizontal movement of the lens.

To move the lens vertically (anterior-posterior movement), a PAD is created with regions of high acoustic pressure above and below the IOL. Manipulation of the lens in the vertical direction is then achieved by vertically shifting the position of these high pressure areas.

The acoustic wavelength λ and consequently the frequency f of the acoustic field should be chosen according to the geometry of the object to be manipulated. For example, the main body of the IOL (the central circular lens part) has a diameter in the range of 6 mm. For horizontal movement or rotation, the distance between the high pressure areas of the PAD should be large enough to accommodate this body between them. The high pressure areas of the considered PAD occur at a distance of λ/2, as in shown. If you choose e.g. E.g. λ/2 as 1.5 times the characteristic dimension of the manipulated object (6 mm), this results in an acoustic wavelength of 18 mm, which in turn results in a desired acoustic frequency of $$f=\frac{c}{\mathrm{\lambda }}=\frac{1500\frac{\text{m}}{\text{s}}}{18\times {10}^{-3}\text{m}}=83.3\text{kHz}.$$

Finally, note that the term “comprising” does not exclude other elements or steps, and the “a” or “an” does not exclude a plural. Also, elements described in connection with various embodiments may be combined. It should also be noted that reference numerals in the claims should not be construed as limiting the scope of the claims.

LIST OF REFERENCE SYMBOLS

1

Displacement device

3

object

5

body part

7

Intraocular lens

9

Eye

11

Capsular bag

13

Ultrasonic transducer arrangement

15

Controllers

17

Ultrasonic generator

19

acoustic lens

21

Ultrasonic sound

23

Pressure amplitude distribution

25

liquid

27

Manipulation of body volume

29

first pressure area with low pressure

31

second pressure area with high pressure

33

Displacement mechanism

35

Fluid coupling medium

37

Fixation mechanism

39

Suction unit

41

sealing lip

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• FR 2211207 B1 [0012]
• DE 19623213 A1 [0012]
• EP 617599 B1 [0012]
• US 7178530 B2 [0012]
• EP 2996649 A1 [0012]
• WO 2016/131055 A1 [0012]
• CA 2213648 A1 [0012]
• US 3990452 A [0012]
• EP 2512599 B1 [0012]
• WO 2017/161348 A1 [0012, 0014, 0017]
• WO 2022/002825 A1 [0022]
• WO 2022/058281 A1 [0022]

Claims (15)

Method for the non-contact, non-invasive displacement of an object (3) in relation to a body part (5) of a human or animal body, the method comprising: Generating an acoustic pressure amplitude distribution (23) in a fluid (25), which is contained in the body part in a manipulation body volume (27) enclosing the object, by irradiating the manipulation body volume (27) with ultrasound (21) produced by an ultrasound transducer arrangement (13). is sent out, Manipulating the ultrasonic transducer arrangement (13) in such a way that the sound pressure amplitude distribution (23) is modified with respect to at least one of its spatial arrangement and its spatial amplitude distribution, so that a force sufficient to displace the object (3) is locally applied by the modified sound pressure amplitude distribution the object (3) is exercised. Procedure according to Claim 1 , where the ultrasound is irradiated with an energy density that is sufficiently low to avoid at least one of the following phenomena: tissue damage, scarring, muscle relaxation, muscle tension, acoustic flow and cavitation within the manipulated body volume (27). Method according to one of the preceding claims, wherein the acoustic pressure amplitude distribution is generated with at least a first pressure region (29) of lower acoustic pressure and at least a second pressure region (31) of higher acoustic pressure, at least one of a size, a geometry and an amplitude of the first and second pressure range (29, 31) is set depending on at least one of the position and geometry properties of the object (3). Procedure according to Claim 3 , wherein the sound pressure amplitude distribution is generated such that the object is predominantly located within the first pressure range (29) with lower sound pressure and is inserted between at least two second pressure ranges (31) with higher sound pressure. Method according to one of the preceding claims, in which the ultrasound is emitted in such a way that it has a wavelength in the volume of the manipulation body (27) which is between 100% and 400% of the lateral dimensions of the object in an irradiation direction of the irradiated ultrasound. Method according to one of the preceding claims, wherein the pressure amplitude distribution (23) is generated so that it completely encloses the object (3). Method according to one of the preceding claims, wherein the volume of the manipulation body (27) is adjusted so that its dimensions are at most three times, preferably at most twice, the dimensions of the object (3). Method according to one of the preceding claims, wherein the ultrasound transducer arrangement (13) is manipulated in such a way that the sound pressure amplitude distribution is at least either laterally displaced or rotated within a plane which crosses an emission direction of the ultrasound. Method according to one of the preceding claims, wherein a fluid coupling medium (35) is arranged between the manipulation body volume (27) and the ultrasound transducer arrangement (13), which has acoustic properties that correspond to the acoustic properties of the fluid surrounding the object (3) in the manipulation body volume (27). within a tolerance of ± 50%, preferably ±40%, in particular ±30%. Method according to one of the preceding claims, wherein during the generation of the ultrasound the ultrasound transducer arrangement (13) is mechanically attached to the body part which includes the manipulation body volume (27). Method according to one of the preceding claims, wherein the object (3) is a lens, in particular an intraocular lens (7), and wherein the manipulation body volume (27) is arranged on an eye (9) of a patient. Device (1) for the non-contact, non-invasive displacement of an object (3) in relation to a body part (5) of a human or animal body, the device (1) comprising: an ultrasound transducer arrangement (13) and a control unit (15) for Controlling the ultrasonic transducer arrangement (13), the control unit (15) and the ultrasonic transducer arrangement (13) being configured to carry out the method according to one of Claims 1 until 11 implement and/or control. Device (1) according to Claim 12 , wherein the ultrasonic transducer arrangement (13) comprises at least two ultrasonic generators (17) which are arranged laterally next to one another, wherein the control unit (15) is configured to operate each of the ultrasonic generators (17) independently of the other ultrasonic generator (17) individually controls so that a pattern of the The ultrasound (21) generated by the ultrasound transducer arrangement (13) is displaced in at least one of a lateral direction and a depth direction. Device (1) according to one of the Claims 12 and 13 , wherein the ultrasonic transducer arrangement (13) comprises at least one acoustic lens (19), wherein the control unit (15) is configured to control the at least one acoustic lens (19) so that a pattern of the ultrasonic transducer arrangement (13) generated Ultrasound is shifted in at least one of a lateral direction and a depth direction. Device (1) according to one of the Claims 12 until 14 , wherein the device (1) further comprises a displacement mechanism (33) configured to mechanically displace at least one component contained in the ultrasonic transducer assembly (13) such that a pattern of the ultrasound generated by the ultrasonic transducer assembly (13) in at least one of a lateral direction and a depth direction is displaced.

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