WO2022052180A1 - Ultrasonic neuromodulation apparatus - Google Patents

Abstract

An ultrasonic neuromodulation apparatus, comprising a planar ultrasonic transducer (100), a Fresnel acoustic lens (200), and an acoustic wave collimator (300), the planar ultrasonic transducer (100), the Fresnel acoustic lens (200), and the acoustic wave collimator (300) being arranged in sequence, a transmitting end of the planar ultrasonic transducer (100) being used for transmitting a planar ultrasonic wave signal, the excitation frequency of the planar ultrasonic transducer (100) being adjustable, and the focal length of the Fresnel acoustic lens (200) increasing or decreasing as the frequency of the planar acoustic wave rises or falls. The ultrasonic focus depth can be adjusted by means of adjusting the frequency of the planar acoustic wave transmitted by the planar ultrasonic transducer (100), providing a simple and convenient method for stimulating brain nuclei of different depths for ultrasonic neuromodulation.

Description

Ultrasound neuromodulation device technical field

The invention relates to the field of ultrasonic nerve regulation, in particular to an ultrasonic nerve regulation device.

Background technique

In recent years, the clinical application of ultrasound is no longer limited to image diagnosis. The therapeutic effect of ultrasound in tumors and brain diseases has gradually become a hot spot in modern medical research. For example, HIFU treatment uses high-intensity focused ultrasound to induce instantaneous hyperthermia, which causes tumor tissue to undergo coagulation and necrosis very quickly, thus being used for tumor thermal treatment; in neuromodulation research, focused sound field can accurately stimulate nerve nuclei and effectively regulate neural circuits. It provides an important means for studying the pathogenesis and treatment of brain functions such as Alzheimer's disease, Parkinson's disease, epilepsy and depression. Ultrasound neuromodulation is the use of ultrasonic waves to propagate in the tissue in the form of pulses or continuous waves, and then affects the acoustic activity of the tissue through the mechanical or thermal effects of ultrasonic waves. By changing the ultrasonic frequency, pulse width, duration and ultrasonic intensity, the nerves at the stimulation site can be stimulated or inhibited, thereby reversibly regulating nerve function in both directions.

The current ultrasonic neuromodulation mainly uses a single-element focused ultrasonic transducer to stimulate the nerve. When using a single-element focused ultrasonic transducer for ultrasonic nerve regulation, it is impossible to stimulate nerves in different positions without changing the structural arrangement of the ultrasonic nerve regulation device. The main reason is that the single-element ultrasonic transducer has a single focusing form. , the focal depth is not adjustable, which limits the flexibility of ultrasound neuromodulation to stimulate nuclei at different depths.

technical problem

The focal depth of the ultrasound neuromodulation device is not adjustable, which limits the flexibility of ultrasound neuromodulation to stimulate nuclei at different depths.

technical solutions

In order to solve the above-mentioned technical problems, the technical solutions adopted in the embodiments of the present application are:

An ultrasonic nerve regulation device, comprising a planar ultrasonic transducer, a Nefer acoustic lens and an acoustic collimator, wherein the planar ultrasonic transducer, the Nefer acoustic lens and the acoustic collimator are arranged in sequence, The transmitting end of the planar ultrasonic transducer is used to transmit planar ultrasonic signals, and the excitation frequency of the planar ultrasonic transducer is adjustable, wherein the focal length of the Nefer acoustic lens increases with the frequency of the planar ultrasonic wave or decrease and increase or decrease.

Optionally, the Nefer acoustic lens includes a plurality of concentric rings, a slit is formed between each adjacent two rings, and the width of each slit extends from the inside to the radial direction. outside gradually decreased.

Optionally, each of the annular rings has the same thickness.

Optionally, the radius of the ring satisfies the following relationship:

Among them, rn represents the radius of the _nth Fresnel region; λ=c/f represents the wavelength of the sound wave emitted by the planar ultrasonic transducer, c represents the speed of sound, and f represents the frequency of the sound wave emitted by the ultrasonic transducer; F represents the normal phenanthrene The preset focal length of the Nell lens.

Optionally, the acoustic wave phase difference between the Fresnel acoustic lens ring and the protrusions and grooves of adjacent slits is π.

Optionally, the plane ultrasonic transducer has a sound exit plane, the plane ultrasonic transducer emits the plane ultrasonic waves on the sound exit plane, and the Nefer acoustic lens is arranged on the sound exit plane. .

Optionally, the ultrasonic transducer can adjust the frequency of the sound waves in the range of 0.5-5 MHz.

Optionally, the ultrasonic transducer is a planar piezoelectric ceramic.

Optionally, the Nefer acoustic lens is made of photosensitive resin, acrylic material or medical silicone rubber.

Optionally, the ultrasonic neuromodulation device further comprises an acoustic collimator;

Wherein, the planar ultrasonic transducer, the Nefer acoustic lens and the acoustic wave collimator are arranged in sequence.

beneficial effect

Based on the present invention, the plane ultrasonic transducer emits plane ultrasonic waves, and the plane ultrasonic waves are formed into point focusing through the Nefer acoustic lens, wherein, since the focal length of the Nefer acoustic lens increases or decreases with the increase or decrease of the frequency of the plane ultrasonic waves, That is to say, by changing the frequency of the plane ultrasonic wave, the position where the plane ultrasonic wave is focused by the Nefer acoustic lens can be changed. Therefore, by adjusting the frequency of the plane ultrasonic wave emitted by the plane ultrasonic transducer, the depth of focus of the ultrasonic wave can be adjusted. It provides a simple, convenient and flexible method for ultrasound neuromodulation to stimulate brain nuclei at different depths.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the accompanying drawings that are used in the description of the embodiments or exemplary technologies. Obviously, the drawings in the following description are only for the present application. In some embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without any creative effort.

1 is a schematic diagram of the overall structure of an ultrasonic nerve regulation device provided by an embodiment of the present invention;

Fig. 2 is an exploded view of an ultrasonic nerve regulation device provided by an embodiment of the present invention;

FIG. 3 is an acoustic path diagram of an ultrasonic neuromodulation device provided by an embodiment of the present invention.

Description of reference numbers:

label	name	label		name
100	Planar Ultrasound Transducer	110	sound plane
200	Nephel Acoustic Lens
300	Sonic Collimator

Embodiments of the present invention

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

The embodiment of the present invention provides an ultrasonic nerve regulation device, which uses ultrasonic waves to stimulate the central nervous system of a site in the form of pulses or continuous waves to generate stimulation or inhibition effects, thereby reversibly regulating nerve function in both directions.

Please refer to FIGS. 1 to 3 , the ultrasonic neuromodulation device includes a planar ultrasonic transducer 100 , a Nefer acoustic lens 200 and an acoustic collimator 300 , the planar ultrasonic transducer 100 , the Nefer acoustic lens 200 and the acoustic collimator 300 . The straighteners 300 are arranged in sequence.

The transmitting end of the planar ultrasonic transducer 100 is used to transmit planar ultrasonic signals, which are parallel high-frequency ultrasonic beams, and the planar ultrasonic transducer 100 can adjust the frequency of the planar ultrasonic waves, that is, the planar ultrasonic transducer 100 can select It can emit plane ultrasonic waves of different frequencies randomly, instead of only emitting plane ultrasonic waves of one frequency fixedly. The Nefer acoustic lens 200 is used to receive the plane ultrasonic wave, focus the plane ultrasonic wave, and form a point focus; in the embodiment of the present invention, preferably, the ultrasonic transducer can adjust the frequency range of the sound wave to be 0.5-20MHz, for example , 0.6MHz, 0.7MHz, 0.8MHz, 1MHz, 1.2MHz, 1.5MHz, 1.8MHz, 2MHz, 3MHz, 4MHz, 5MHz, 6MHz, 8MHz, 10MHz, 12MHz, 15MHz, 10MHz. The plane ultrasonic wave is diffracted after passing through the Fresnel lens, and finally, a focused sound field is formed on the far plane ultrasonic transducer 100 side along the plane ultrasonic wave propagation direction. The focal length of the Nefer acoustic lens 200 increases or decreases as the frequency of the plane ultrasonic wave increases or decreases.

Based on the ultrasonic nerve regulation device provided in the embodiment of the present invention, the planar ultrasonic transducer 100 transmits planar ultrasonic waves, and the planar ultrasonic waves are formed into point focusing by the Nefer acoustic lens 200, wherein, since the focal length of the Nefer acoustic lens 200 varies with the plane ultrasonic waves The frequency increases or decreases as the frequency increases or decreases, that is, by changing the frequency of the plane ultrasonic wave, the position where the plane ultrasonic wave is focused by the Nefer acoustic lens 200 can be changed. Therefore, by adjusting the plane ultrasonic transducer 100 to transmit The frequency of the plane ultrasonic wave can be adjusted to adjust the ultrasonic focusing depth, which provides a simple, convenient and flexible method for the ultrasonic neural regulation and stimulation of brain nuclei of different depths.

It should be noted here that the structural structure of the Nefer acoustic lens 200 may be configured such that the focal length of the Nefer acoustic lens 200 increases as the frequency of the plane ultrasonic wave increases, or it may be The focal length decreases as the frequency of the planar ultrasound increases.

Referring to FIG. 1, in an embodiment of the present invention, the Nefer acoustic lens 200 includes a plurality of concentric rings, a slit is formed between each adjacent two rings, and the width of each slit is along the The radial direction gradually decreases from inside to outside. Optionally, the ring can be made of photosensitive resin, or can be made of acrylic material, or can be made of medical silicone rubber. In this embodiment, the thickness of each arc is the same.

Specifically, the radius of the ring is determined according to the Fresnel diffraction formula

Satisfy the relationship:

Among them, rn represents the radius of the _nth Fresnel region; λ=c/f represents the wavelength of the sound wave emitted by the planar ultrasonic transducer, c represents the speed of sound, and f represents the frequency of the sound wave emitted by the planar ultrasonic transducer 100; F represents the The preset focal length of a normal Fresnel lens.

Wherein, for example, the frequency of the sound wave emitted by the ultrasonic transducer is selected to be 8MHz, and the preset focal depth F=18mm. Therefore, the wavelength of the sound wave is λ=0.1875mm, and the radii of the Fresnel regions are respectively r1=1.8321mm and r2= 2.5943mm, r3=3.1815mm, r4=3.6784mm, r5=4.1178mm, r6=4.5166mm, r7=4.8846mm, then the widths of the Fresnel lens protrusions 32 are: d1=2r1=3.6642mm, d2=r3 –r2=1.8321mm, d3=r5–r4=1.8321mm.

Specifically, in this embodiment, according to the principle of Fresnel diffraction, the phase difference between two adjacent regions of the Fresnel lens is π, and the acoustic wave phase difference between the annular portion of the Fresnel acoustic lens 200 and the adjacent slit is π, under this condition, the best ultrasonic focusing effect can be achieved.

The protrusion and groove thickness can be calculated from the following formula:

in

represents the phase difference of the Fresnel lens protrusions and grooves from the surface, for this Fresnel lens

In the embodiment, the material of the Fresnel lens is medical silicone rubber, and its sound speed is c ₁ =980m/s, and the thickness of the Fresnel lens is t=0.27mm.

Specifically, please refer to FIG. 2 and FIG. 3 , the planar ultrasonic transducer 100 has a sound-emitting plane 110 , the planar ultrasonic transducer 100 emits planar ultrasonic waves on the sound-emitting plane 110 , and the Nefer acoustic lens 200 is arranged on the sound-emitting plane 110 , that is, the Nefer acoustic lens 200 is directly attached to the sound-emitting plane 110 .

In the embodiment of the present invention, the ultrasonic transducer is a planar piezoelectric ceramic, and the structure is relatively simple, which is convenient for production and manufacture, and is beneficial to reduce the production and manufacture cost of the ultrasonic nerve regulation device.

In the embodiment of the present invention, the diameter of the inner cylinder of the acoustic collimator 300 is tapered along the direction away from the planar ultrasonic transducer 100 .

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. Inside.

Claims (9)

1. An ultrasonic nerve regulation device, characterized in that it includes a planar ultrasonic transducer, a Nefer acoustic lens and an acoustic wave collimator, the planar ultrasonic transducer, the Nefer acoustic lens and the acoustic wave collimator The transmitters are arranged in sequence, the transmitting end of the plane ultrasonic transducer is used to transmit plane ultrasonic signals, and the excitation frequency of the plane ultrasonic transducer is adjustable, wherein the focal length of the Nefer acoustic lens varies with the plane acoustic wave The frequency increases or decreases as the frequency increases or decreases.
2. The ultrasonic neuromodulation device according to claim 1, wherein the Nefer acoustic lens comprises a plurality of concentric rings, and a slit is formed between each adjacent two rings, and each of the rings is formed with a slit. The width of the slit gradually decreases from the inside to the outside along the radial direction.
3. The ultrasonic neuromodulation device according to claim 2, wherein each of the annular rings has the same thickness.
4. The ultrasonic neuromodulation device of claim 2, wherein the radius of the annular ring satisfies the following relationship:

   

   Among them, rn represents the radius of the _nth Fresnel region; λ=c/f represents the wavelength of the sound wave emitted by the planar ultrasonic transducer, c represents the speed of sound, and f represents the frequency of the sound wave emitted by the ultrasonic transducer; F represents the normal phenanthrene The preset focal length of the Nell lens.
5. The ultrasonic neuromodulation device according to claim 1, wherein the acoustic wave phase difference between the Fresnel acoustic lens and the adjacent slits is π.
6. The ultrasonic nerve regulation device according to claim 1, wherein the planar ultrasonic transducer has a sound exit plane, and the planar ultrasound transducer emits the plane ultrasonic waves on the sound exit plane, and the plane ultrasonic wave is emitted by the planar ultrasound transducer. The Nefer acoustic lens is arranged on the sound exit plane.
7. The ultrasonic nerve regulation device according to claim 1, wherein the ultrasonic transducer can adjust the frequency of the sound wave in a range of 0.5-5 MHz.
8. The ultrasonic nerve regulation device according to claim 1, wherein the ultrasonic transducer is a planar piezoelectric ceramic.
9. The ultrasonic neuromodulation device according to claim 1, wherein the Nefer acoustic lens is made of photosensitive resin, acrylic material or medical silicone rubber.

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