Stimulation and imaging device

Abstract

The stimulation and imaging device provided by the embodiment of the invention comprises at least one detection unit, a magnetic field generation device, a signal processing module, an image reconstruction module and a stimulation device. The detection unit comprises a transducer and an electrode plate, and a sample to be detected is arranged between the transducer and the electrode plate. The electrode plate emits an excitation electric signal to a to-be-detected sample, and the excitation electric signal forms a first induction eddy current signal in the to-be-detected sample. The magnetic field generating device generates a steady-state magnetic field, and the first induction eddy current signal generates a coupling sound signal in the steady-state magnetic field. The stimulation device stimulates the to-be-tested sample. The transducer obtains a coupling sound signal generated by a to-be-tested sample in a stimulation state. The signal processing module obtains a pulse compression signal. The image reconstruction module is used for reconstructing the to-be-tested sample image in the stimulation state. According to the stimulation and imaging device provided by the embodiment of the invention, the electromagnetic field distribution imaging of the sample in the stimulation state is obtained, and the monitoring visualization of the electromagnetic field under stimulation is realized.

Description

Technical Field

[0001] This invention relates to the field of stimulation imaging technology, and more particularly to a stimulation and imaging device. Background Technology

[0002] Neuromodulation is one of the core methods in brain science research, and various neuromodulation techniques based on physical factors have been developed.

[0003] Currently, the assessment of stimulation effects largely relies on placing detection electrodes on the sample to indirectly obtain relevant signals.

[0004] However, this indirect monitoring method also affects the accuracy and resolution of the research results to some extent. Furthermore, the stimuli produced within biological tissues are difficult to monitor directly, which greatly hinders the further advancement of research and application of stimulus mechanisms. Summary of the Invention

[0005] This invention provides a stimulation and imaging device to achieve electromagnetic-acoustic coupling detection and visualization under stimulation.

[0006] This invention provides a stimulation and imaging device, including at least one detection unit, a magnetic field generating device, a signal processing module, an image reconstruction module, and a stimulation device. The detection unit includes a transducer and an electrode plate, with a test sample positioned between the transducer and the electrode plate. The electrode plate emits an excitation electrical signal to the test sample, which generates a first induced eddy current signal in the test sample. The magnetic field generating device generates a steady magnetic field in the region where the test sample is located, and the first induced eddy current signal generates a coupled acoustic signal in the steady magnetic field. The stimulation device generates a stimulation magnetic field according to preset stimulation parameters, which stimulates the nerves or muscles of the test sample. The transducer acquires the coupled acoustic signal generated by the test sample under stimulation. The signal processing module is communicatively connected to both the transducer and the electrode plate, and performs pulse compression on the coupled acoustic signal according to the excitation electrical signal to obtain a pulse-compressed signal. The image reconstruction module is communicatively connected to the signal processing module and converts the pulse-compressed signal into an imaging signal to reconstruct an image of the test sample under stimulation.

[0007] Optionally, the signal processing module includes: a correlation operation unit for calculating the cross-correlation function between the coupled acoustic signal and the excitation electrical signal; and a compression unit, which is communicatively connected to the correlation operation unit for generating a pulse compression signal based on the cross-correlation function.

[0008] Optionally, the image reconstruction module includes: a peak extraction unit, which is communicatively connected to the compression unit, for obtaining the peak time offset and amplitude value from the pulse compression signal; a depth information mapping unit, which is communicatively connected to the peak extraction unit, for generating depth information based on the peak time offset; a reflection intensity mapping unit, which is communicatively connected to the peak extraction unit, for generating acoustic reflection intensity information based on the amplitude value; and a spatial reconstruction unit, which is communicatively connected to both the depth information mapping unit and the reflection intensity mapping unit, for reconstructing the spatial distribution image of the sample under test based on the depth information and the acoustic reflection intensity information.

[0009] Optionally, the stimulation and imaging device includes a ring frame on which 4n transducers (H1, H2, ..., H4n) and 4n electrode plates (D1, D2, ..., D4n) are arranged, with the transducers and electrode plates evenly and alternately arranged adjacent to each other along the ring frame; where n is an integer greater than or equal to 1; the stimulation and imaging device also includes a time-sharing drive module, which is communicatively connected to each of the 4n electrode plates, and is used to execute an excitation cycle; the excitation cycle includes starting from i = 1 and incrementing sequentially to i = 4n, controlling the i-th electrode plate Di to emit an excitation electrical signal, and simultaneously controlling the (i+2n)mod(4n)-th electrode plate D(i+2) to emit an excitation electrical signal. The (i+n-1)mod(4n) transducer is grounded to form an excitation current loop; the (i+n-1)mod(4n) transducer H(i+n-1)mod(4n) and the (i+3n-1)mod(4n) transducer H(i+3n-1)mod(4n) receive the coupled acoustic signal and collect the coupled acoustic signal from different directions; the signal processing module includes a multi-channel compression unit, which is communicatively connected to each transducer and is used to generate pulse compression signals from different directions based on the coupled acoustic signal from different directions; the image reconstruction module includes a spatial fusion unit, which is used to reconstruct the spatial distribution image of the sample under test based on the pulse compression signals from different directions.

[0010] Optionally, the time-sharing drive module is also used to repeatedly execute the excitation cycle m times; where m is an integer greater than or equal to 2;

[0011] The multi-channel compression unit is also used to perform pulse compression on the coupled acoustic signals collected in m excitation cycles for each direction, and obtain m sets of pulse compressed signals.

[0012] The spatial fusion unit is also used to perform mean calculation on m sets of pulse compression signals in each direction to obtain the average pulse compression signal in each direction, and reconstruct the spatial distribution image of the sample under test based on the average pulse compression signal.

[0013] Optionally, the direction of the stimulating magnetic field is parallel to the direction of the steady magnetic field;

[0014] The stimulation magnetic field is also used to generate a second induced eddy current signal within the sample to be tested;

[0015] The first and second induced eddy current signals generate a coupled acoustic signal under the action of a steady magnetic field.

[0016] Optionally, the stimulation device is a stimulation coil;

[0017] The stimulation coil is positioned on the side of the sample to be tested that is close to or away from the magnetic field generating device; the current path of the stimulation coil is perpendicular to the magnetic field direction of the steady magnetic field.

[0018] Optionally, the stimulation and imaging device may also include detection electrodes;

[0019] The detection electrode is placed on the organism where the sample is located. The detection electrode is used to acquire the electrophysiological signal generated by the sample in response to the stimulation magnetic field. The electrophysiological signal includes electrophysiological characteristic parameters.

[0020] Optionally, the signal processing module also includes an adjustment submodule, which is communicatively connected to the detection electrode. The adjustment submodule is used to compare the electrophysiological characteristic parameters with preset thresholds of the electrophysiological characteristic parameters and adjust the preset stimulation parameters according to the comparison results.

[0021] Optionally, the stimulation and imaging device further includes an excitation electrical signal source; the excitation electrical signal source includes a sequence generator and a signal generator; the sequence generator is used to generate an excitation sequence; the signal generator is communicatively connected to both the sequence generator and the electrode plate, and the signal generator generates and sends an excitation electrical signal to the electrode plate based on the excitation sequence and a preset periodic signal.

[0022] This invention provides a stimulation and imaging device, comprising at least one detection unit, a magnetic field generating device, a signal processing module, an image reconstruction module, and a stimulation device. The detection unit includes a transducer and an electrode plate, with a sample to be tested disposed between them. The electrode plate emits an excitation electrical signal to the sample, which generates a first induced eddy current signal in the sample. The magnetic field generating device generates a steady magnetic field, and the first induced eddy current signal generates a coupled acoustic signal within the steady magnetic field. The stimulation device stimulates the sample. The transducer acquires the coupled acoustic signal generated by the sample under stimulation. The signal processing module acquires a pulse compression signal. The image reconstruction module reconstructs an image of the sample under stimulation. This invention provides a stimulation and imaging device that acquires an image of the electromagnetic field distribution of a sample under stimulation, realizing the monitoring and visualization of the electromagnetic field under stimulation. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of a stimulation and imaging device provided in an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of another stimulation and imaging device provided in an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the structure of a detection unit provided in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of an excitation electrical signal provided in an embodiment of the present invention. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0028] This invention provides a stimulation and imaging device. Figure 1 This is a schematic diagram of the structure of a stimulation and imaging device provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of another stimulation and imaging device provided in an embodiment of the present invention. Figure 1 and Figure 2 As shown, the device includes at least one detection unit 10, a magnetic field generator 20, a signal processing module 30, an image reconstruction module 40, and a stimulation device 50.

[0029] The detection unit 10 includes a transducer 11 and an electrode plate 12, with the sample to be tested positioned between the transducer 11 and the electrode plate 12.

[0030] The electrode plate 12 is used to transmit an excitation electrical signal to the sample under test, and the excitation electrical signal forms a first induced eddy current signal in the sample under test.

[0031] The magnetic field generating device 20 is used to generate a steady magnetic field in the area where the sample to be tested is located, and the first induced eddy current signal generates a coupled acoustic signal in the steady magnetic field.

[0032] The stimulation device 50 is used to generate a stimulation magnetic field according to preset stimulation parameters. The stimulation magnetic field is used to stimulate the nerves or muscles of the sample to be tested.

[0033] The transducer 11 is used to acquire the coupled acoustic signal generated by the test sample under stimulation.

[0034] The signal processing module 30 is communicatively connected to the transducer 11 and the electrode plate 12 respectively. The signal processing module 30 is used to pulse compress the coupled acoustic signal according to the excitation electrical signal to obtain a pulse compressed signal.

[0035] The image reconstruction module 40 is communicatively connected to the signal processing module 30. The image reconstruction module 40 is used to convert the pulse compression signal into an imaging signal and reconstruct the image of the test sample under the stimulation state.

[0036] Among them, the excitation electrical signal can be understood as the initial excitation source electrical signal with a specific waveform or frequency; the first induced eddy current signal can be understood as the eddy current signal generated inside the sample under test due to electromagnetic induction under the action of the excitation electrical signal; the coupled acoustic signal can be understood as the acoustic wave signal generated when the first induced eddy current signal vibrates the medium of the sample under test in a steady magnetic field due to the action of the Lorentz force, and this signal carries relevant information about the sample under test in the stimulation state.

[0037] Specifically, the electrode plate 12 of the detection unit 10 emits an excitation electrical signal, forming a first induced eddy current signal in the sample 1 under test. The magnetic field generating device 20 generates a steady magnetic field toward the sample 1 under test. In the steady magnetic field, the first induced eddy current signal vibrates due to the Lorentz force, causing the medium in the sample 1 to vibrate, thereby generating a coupled acoustic signal. Based on this, the stimulation device 50 generates a stimulation magnetic field according to preset parameters. The stimulation magnetic field can be understood as an alternating magnetic field. The alternating magnetic field forms an alternating electric field in the sample, thereby stimulating the nerves or muscles of the sample, putting the sample in a stimulated state. The transducer 11 acquires the coupled acoustic signal and transmits it to the signal processing module 30. The signal processing module 30 combines the frequency, phase, and other characteristics of the excitation electrical signal to perform pulse compression processing on the stimulation signal, ultimately obtaining a pulse compressed signal with improved signal-to-noise ratio and clearer information. The image reconstruction module 40 uses pulse compression signals and image reconstruction algorithms, such as back projection or Fourier transform, to convert them into imaging signals that reflect the distribution of internal physical characteristics of the sample 1 under test, thereby reconstructing the structural and functional images of the sample 1 under the stimulus state.

[0038] Continue to refer to Figure 1 and Figure 2 In an optional embodiment, the signal processing module 30 includes:

[0039] The correlation operation unit 31 is used to calculate the cross-correlation function between the coupled acoustic signal and the excitation electrical signal;

[0040] The compression unit 32 is communicatively connected to the correlation operation unit 31 and is used to generate a pulse compression signal based on the cross-correlation function.

[0041] Specifically, after the electrode plate 12 acquires the coupled acoustic signal of the sample 1 under stimulation, the correlation operation unit 31 acquires the coupled acoustic signal and the excitation electrical signal respectively through the communication connection with the transducer 11 and the electrode plate 12. Based on the principle of cross-correlation operation, the cross-correlation function between the coupled acoustic signal and the excitation electrical signal is calculated. This function can reflect the distribution of effective components of the same origin in the coupled acoustic signal and the excitation electrical signal, such as frequency and phase characteristics. Based on the cross-correlation function calculated by the correlation operation unit 31, the compression unit 32 processes the coupled acoustic signal using the cross-correlation function as a filter function through a pulse compression algorithm, such as a matched filtering algorithm. This completes the time-dimensional compression processing of the coupled acoustic signal characterized by the cross-correlation function, generating a pulse compressed signal with narrower pulse width, more prominent peak amplitude, and improved signal-to-noise ratio and resolution. Subsequently, the compression unit 32 transmits the generated pulse compressed signal to the image reconstruction module 40.

[0042] This invention provides a stimulation and imaging device, comprising at least one detection unit, a magnetic field generating device, a signal processing module, an image reconstruction module, and a stimulation device. The detection unit includes a transducer and an electrode plate, with a sample to be tested disposed between them. The electrode plate emits an excitation electrical signal to the sample, which generates a first induced eddy current signal in the sample. The magnetic field generating device generates a steady magnetic field, and the first induced eddy current signal generates a coupled acoustic signal within the steady magnetic field. The stimulation device stimulates the sample. The transducer acquires the coupled acoustic signal generated by the sample under stimulation. The signal processing module acquires a pulse compression signal. The image reconstruction module reconstructs an image of the sample under stimulation. This invention provides a stimulation and imaging device that acquires an image of the electromagnetic field distribution of a sample under stimulation, realizing the monitoring and visualization of the electromagnetic field under stimulation.

[0043] Continue to refer to Figure 1 and Figure 2 In an optional embodiment, the image reconstruction module 40 includes:

[0044] The peak extraction unit 41 is communicatively connected to the compression unit 32 and is used to obtain the peak time offset and amplitude value from the pulse compression signal.

[0045] The depth information mapping unit 42 is communicatively connected to the peak extraction unit 41 and is used to generate depth information based on the peak time offset.

[0046] The reflection intensity mapping unit 43 is communicatively connected to the peak extraction unit 41 and is used to generate acoustic reflection intensity information based on the amplitude value.

[0047] The spatial reconstruction unit 44 is communicatively connected to the depth information mapping unit 42 and the reflection intensity mapping unit 43, respectively, and is used to reconstruct the spatial distribution image of the sample under test based on the depth information and acoustic reflection intensity information.

[0048] Specifically, after the compression unit 32 generates a pulse compression signal and transmits it to the image reconstruction module 40, the peak extraction unit 41, based on the pulse compression signal sent by the compression unit 32, uses signal peak detection algorithms, such as thresholding or extreme value search, to identify the difference between the occurrence time of each effective peak and the reference time (i.e., peak time offset), and the signal intensity (i.e., amplitude value) corresponding to each peak from the waveform of the pulse compression signal. These two sets of parameters are then transmitted to the depth information mapping unit 42 and the reflection intensity mapping unit 43, respectively. After receiving the peak time offset, the depth information mapping unit 42, combined with the known propagation speed of the magnetoacoustic excitation signal in the sample under test, maps each peak time offset to the corresponding depth value within the sample according to the formula "depth = propagation speed × peak time offset / 2", forming depth information for different response regions of the sample under test. The reflection intensity mapping unit 43 receives the amplitude value and uses an intensity mapping algorithm to convert the amplitude value into an acoustic reflection intensity parameter conforming to image grayscale or color mapping standards, generating acoustic reflection intensity information that characterizes the reflection characteristics of different regions of the sample under test. Finally, the spatial reconstruction unit 44 receives depth information and acoustic reflection intensity information, and then uses a spatial image reconstruction algorithm to take the sample position corresponding to each depth value as the spatial coordinates of the image, and the acoustic reflection intensity information of that position as the image pixel value of the corresponding coordinate point. Point by point or region by region, a spatial distribution image combining the depth distribution and reflection intensity distribution of different regions inside the sample 1 under test is constructed, and the reconstruction of the sample image under test is finally completed.

[0049] Figure 3 This is a schematic diagram of the structure of a detection unit provided in an embodiment of the present invention. (Continuing to refer to...) Figures 1-3In an optional embodiment, the stimulation and imaging device includes a ring frame on which 4n transducers 11 (H1, H2, ..., H4n) and 4n electrode plates 12 (D1, D2, ..., D4n) are disposed, with the transducers 11 and electrode plates 12 evenly and alternately arranged adjacent to each other along the ring frame. The stimulation and imaging device also includes a time-sharing drive module 60, which is communicatively connected to each of the 4n electrode plates 12 and is used to execute excitation cycles. The excitation cycle starts from i=1 and increments sequentially to i=4n, controlling the i-th electrode plate Di to emit an excitation electrical signal, while simultaneously grounding the (i+2n)mod(4n)-th electrode plate D(i+2n)mod(4n) to form an excitation current loop; the coupled acoustic signal is received through the (i+n-1)mod(4n)-th transducer H(i+n-1)mod(4n) and the (i+3n-1)mod(4n)-th transducer H(i+3n-1)mod(4n), acquiring coupled acoustic signals from different directions. The signal processing module 30 includes a multi-channel compression unit 33, which is communicatively connected to each transducer 11, and is used to generate pulse compressed signals from different directions based on the coupled acoustic signals from different directions. The image reconstruction module 40 includes a spatial fusion unit 45, which is used to reconstruct the spatial distribution image of the sample under test based on the pulse compressed signals from different directions.

[0050] Where n is an integer greater than or equal to 1.

[0051] Specifically, the detection unit 10 adopts a ring frame design, on which 4n transducers 11 and 4n electrode plates 12 are evenly and alternately arranged. The time-division driving module 60 controls the i-th electrode plate 12 to emit excitation electrical signals sequentially from i=1 to i=4n, while simultaneously grounding the (i+2n)mod(4n)-th electrode plate 12 to form a stable excitation current loop. During this process, the (i+n-1)mod(4n)-th and (i+3n-1)mod(4n)-th transducers 11 synchronously receive coupled acoustic signals, realizing the acquisition of signals from different orientations of the sample. The multi-channel compression unit 33 performs pulse compression processing on the coupled acoustic signals from different orientations in combination with the excitation electrical signals, generating pulse compressed signals corresponding to each orientation, effectively improving the signal-to-noise ratio and time resolution of the signal. The spatial fusion unit 45 integrates the pulse compressed signals from different orientations to reconstruct the spatial distribution image of the sample under test.

[0052] For example, when n=1, four transducers 11 (H1-H4) and four electrode plates 12 (D1-D4) are evenly distributed on the annular frame, arranged alternately in the following order: D1→H1→D2→H2→D3→H3→D4→H4→D1. The excitation cycle is executed sequentially from i=1 to i=4, with each round corresponding to one electrode plate 12 transmitting a signal, one electrode plate 12 being grounded, and two transducers 11 receiving signals. In the first round (i=1), the time-division drive module 60 controls the first electrode plate D1 to transmit an excitation signal, while simultaneously grounding the (i+2n)mod(4n)=(1+2×1)mod4=3rd electrode plate D3, forming an excitation current loop of D1→sample under test→D3. The excitation current loop generates the first induced eddy current in the sample under test 1. The (i+n-1)mod4 = (1+1-1)mod4 = 1 transducer H1 and the (i+3n-1)mod4 = (1+3×1-1)mod4 = 3 transducers H3 receive the coupling acoustic signal generated by the sample under test 1. In the second round (i=2): D2 is controlled to emit an excitation electrical signal, grounding the (2+2)mod4 = 4 electrode plates D4, forming a "D2→sample→D4" loop. The (2+1-1)mod4 = 2 transducers H2 and the (2+3-1)mod4 = 4 transducers H4 receive the coupling acoustic signal. Round 3 (i=3): Control D3 to emit an excitation signal, grounding the (3+2)mod4=1st electrode plate D1 to form a "D3→sample→D1" loop; receive the coupling acoustic signal through the (3+1-1)mod4=3rd transducer H3 and the (3+3-1)mod4=1st transducer H1. Round 4 (i=4): Control D4 to emit an excitation signal, grounding the (4+2)mod4=2nd electrode plate D2 to form a "D4→sample→D2" loop; receive the coupling acoustic signal through the (4+1-1)mod4=4th transducer H4 and the (4+3-1)mod4=2nd transducer H2. After the 4-round cycle, the multi-channel compression unit 33 performs pulse compression on the 4 sets of coupling acoustic signals collected by H1-H4 respectively, obtaining 4 sets of pulse compressed signals from different directions; the spatial fusion unit 45 integrates the above signals to reconstruct the spatial distribution image of the sample 1 under test.

[0053] Continue to refer to Figure 1 and Figure 2 In an optional embodiment, the time-sharing drive module 60 is further configured to repeatedly execute the excitation cycle m times; where m is an integer greater than or equal to 2.

[0054] The multi-channel compression unit 33 is also used to perform pulse compression on the coupled acoustic signals collected in m excitation cycles for each direction, and obtain m sets of pulse compressed signals.

[0055] The spatial fusion unit 45 is also used to perform mean calculation on m sets of pulse compression signals in each direction to obtain the average pulse compression signal in each direction, and reconstruct the spatial distribution image of the sample to be tested based on the average pulse compression signal.

[0056] Specifically, the time-division drive module repeatedly executes the excitation cycle m times, that is, it completes the signal transmission, corresponding grounding, and transducer reception processes of all electrode plates multiple times in the same order and according to the same rules. The multi-channel compression unit performs pulse compression on the coupled acoustic signals acquired in the m cycles for each azimuth. By combining this with excitation electrical signal processing, it improves the signal-to-noise ratio and temporal resolution of each signal group, resulting in m sets of pulse-compressed signals. The spatial fusion unit then performs averaging on the m sets of pulse-compressed signals for each azimuth. This averaging process cancels out random noise and interference, thereby improving the clarity and accuracy of the reconstructed image.

[0057] Continue to refer to Figure 1 and Figure 2 In an optional embodiment, the direction of the stimulating magnetic field is parallel to the direction of the steady magnetic field;

[0058] The stimulation magnetic field is also used to generate a second induced eddy current signal within the sample to be tested;

[0059] The first and second induced eddy current signals generate a coupled acoustic signal under the action of a steady magnetic field.

[0060] Specifically, the direction of the stimulating magnetic field is parallel to the direction of the steady magnetic field, ensuring that the two magnetic fields form a stable superimposed magnetic field environment in the sample area and avoiding signal interference caused by chaotic magnetic field directions. When the stimulating magnetic field acts on the sample, it induces a second induced eddy current signal inside the sample. At this time, the sample simultaneously contains a first induced eddy current signal formed by the excitation electrical signal of the electrode plate and a second induced eddy current signal formed by the stimulating magnetic field. The two induced eddy current signals drive the sample medium to vibrate under the action of the Lorentz force. On the one hand, the parallel magnetic field directions ensure the stability of the magnetic field environment and reduce signal noise. On the other hand, the superposition of the two induced eddy current signals enhances the intensity of the coupled acoustic signal.

[0061] Continue to refer to Figure 1 and Figure 2 In an optional embodiment, the stimulation device 50 is a stimulation coil;

[0062] The stimulation coil is positioned on the side of the sample to be tested that is close to or away from the magnetic field generating device 20; the current path of the stimulation coil is perpendicular to the magnetic field direction of the steady magnetic field.

[0063] Specifically, the stimulation coil is positioned on the side of the sample to be tested that is close to or away from the magnetic field generator, reducing interference from the steady magnetic field generated by the magnetic field generator on the alternating magnetic field generated by the stimulation coil. The current path of the stimulation coil is perpendicular to the magnetic field direction of the steady magnetic field, and the stimulation magnetic field generated by the stimulation coil is in the same direction as the steady magnetic field, making the coupled acoustic signal generated by the first and second induced eddy current signals in the steady magnetic field stronger and richer in information.

[0064] Continue to refer to Figure 2 In an optional embodiment, the stimulation and imaging device further includes a detection electrode 70;

[0065] The detection electrode 70 is disposed on the organism where the sample to be tested is located. The detection electrode 70 is used to acquire the electrophysiological signal generated by the sample to be tested in response to the stimulation magnetic field. The electrophysiological signal includes electrophysiological characteristic parameters.

[0066] Electrophysiological characteristic parameters can be understood as quantitative indicators obtained from organisms that reflect the electrophysiological activity state of the sample under test and surrounding tissues. Examples include the peak value of action potentials, the frequency of neural electrical signals, and the interval of electrocardiogram signals, which can directly characterize the functional state of biological tissues.

[0067] Specifically, the detection electrode 70 is placed on the organism where the sample 1 is located, such as the surface of human skin. The detection electrode 70 senses and collects the electrophysiological changes of the sample 1 caused by the stimulation signal through electrical connection with the surface of the organism, and obtains electrophysiological signals containing electrophysiological characteristic parameters such as action potential, membrane potential, and electrocardiogram signal characteristic values.

[0068] Continue to refer to Figure 2 In an optional embodiment, the signal processing module 30 further includes an adjustment submodule 34, which is communicatively connected to the detection electrode 70. The adjustment submodule 34 is used to compare the electrophysiological characteristic parameters with a preset threshold of the electrophysiological characteristic parameters and adjust the preset stimulation parameters according to the comparison result.

[0069] Among them, the preset threshold of electrophysiological characteristic parameters can be understood as a pre-set reference value or reference range used to determine whether the electrophysiological activity of the sample under test is within the normal or target range.

[0070] Specifically, the regulation submodule 34 acquires electrophysiological signals containing electrophysiological characteristic parameters through the detection electrode 60. The regulation submodule 34 compares the extracted electrophysiological characteristic parameters with preset electrophysiological characteristic parameter thresholds. If the electrophysiological characteristic parameters are below the threshold, the electrical signal intensity reflecting tissue activity is insufficient, therefore, the magnetoacoustic excitation signal needs to be enhanced based on the comparison result, such as by increasing the power of the excitation signal through a power amplifier. Conversely, if the parameters are above the threshold, an excessively strong signal may cause stimulation and damage to the tissue, thus the magnetoacoustic excitation signal is weakened.

[0071] Continue to refer to Figure 2 In an optional embodiment, the stimulation and imaging device further includes an excitation electrical signal source 80; the excitation electrical signal source 80 includes a sequence generator 81 and a signal generator 82; the sequence generator 81 is used to generate an excitation sequence; the signal generator 82 is communicatively connected to the sequence generator 81 and the electrode plate 12 respectively, and the signal generator 82 generates and sends an excitation electrical signal to the electrode plate 12 based on the excitation sequence and a preset periodic signal.

[0072] The excitation sequence can be understood as a discrete numerical sequence with specific coding rules. Different sequence combinations can change the spectral characteristics and time distribution of the excitation signal, thereby optimizing the signal's anti-interference ability and resolution. The preset periodic signal can be understood as a pre-set continuous waveform signal with fixed period and frequency characteristics, such as a sine signal or a cosine signal.

[0073] Specifically, during the operation of the device, the sequence generator 81 generates an excitation sequence according to a preset encoding rule. The signal generator 82 calls a preset periodic signal and modulates the excitation sequence with the preset periodic signal to generate a pulse train signal with specific encoding characteristics, i.e., an excitation electrical signal. Finally, the signal generator 82 sends the excitation electrical signal to the sample under test 1 through the electrode plate 12. The excitation electrical signal forms a first induced eddy current signal in the sample under test 1. In a steady magnetic field, the first induced eddy current signal, due to the Lorentz force, causes the medium in the sample under test 1 to vibrate, thereby generating a coupled acoustic signal.

[0074] For example, such as Figure 4 As shown, the excitation sequence is a 7-bit excitation sequence: -1, -1, -1, +1, -1, +1, +1. The preset periodic signal is a sine wave, and the excitation electrical signal is a pulse train formed by amplitude modulation of the sine wave by the 7-bit excitation sequence. That is, the sine wave in the first period is modulated by -1 to be inverted, the sine wave in the second period is modulated by -1 to be inverted, the sine wave in the third period is modulated by -1 to be inverted, the sine wave in the fourth period is modulated by +1 to be inverted (i.e., remains unchanged), the sine wave in the fifth period is modulated by -1 to be inverted, the sine wave in the sixth period is modulated by +1 to be inverted, and the sine wave in the seventh period is modulated by +1 to be inverted, ultimately forming a pulse train signal composed of 7 modulated sine wave periods.

[0075] Continue to refer to Figure 4 In an optional embodiment, the excitation electrical signal is a periodic pulse signal, wherein the duration of a single pulse in the periodic pulse signal is 350 μs and the pulse repetition period is 1 ms.

[0076] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A stimulation and imaging device, characterized in that, It includes at least one detection unit, a magnetic field generator, a signal processing module, an image reconstruction module, and a stimulation device; The detection unit includes a transducer and an electrode plate, and the sample to be tested is placed between the transducer and the electrode plate; The electrode plate is used to transmit an excitation electrical signal to the sample under test, and the excitation electrical signal forms a first induced eddy current signal in the sample under test. The magnetic field generating device is used to generate a steady magnetic field in the region where the sample to be tested is located, and the first induced eddy current signal generates a coupled acoustic signal in the steady magnetic field. The stimulation device is used to generate a stimulation magnetic field according to preset stimulation parameters, and the stimulation magnetic field is used to stimulate the nerves or muscles of the sample to be tested. The transducer is used to acquire the coupled acoustic signal generated by the test sample under a stimulated state; The signal processing module is communicatively connected to the transducer and the electrode plate, and is used to perform pulse compression on the coupled acoustic signal according to the excitation electrical signal to obtain a pulse compressed signal. The image reconstruction module is communicatively connected to the signal processing module. The image reconstruction module is used to convert the pulse compression signal into an imaging signal and reconstruct the image of the test sample under stimulation.

2. The stimulation and imaging device according to claim 1, characterized in that, The signal processing module includes: The correlation calculation unit is used to calculate the cross-correlation function between the coupled acoustic signal and the excitation electrical signal; The compression unit is communicatively connected to the related computation unit and is used to generate the pulse compression signal according to the cross-correlation function.

3. The stimulation and imaging device according to claim 2, characterized in that, The image reconstruction module includes: A peak extraction unit, which is communicatively connected to the compression unit, is used to obtain the peak time offset and amplitude value from the pulse compression signal; A depth information mapping unit, which is communicatively connected to the peak extraction unit, is used to generate depth information based on the peak time offset. A reflection intensity mapping unit, which is communicatively connected to the peak extraction unit, is used to generate acoustic reflection intensity information based on the amplitude value. The spatial reconstruction unit is communicatively connected to the depth information mapping unit and the reflection intensity mapping unit, respectively, and is used to reconstruct the spatial distribution image of the sample under test based on the depth information and the acoustic reflection intensity information.

4. The stimulation and imaging device according to claim 1, characterized in that, The stimulation and imaging device includes a ring frame on which 4n transducers (H1, H2, ..., H4n) and 4n electrode plates (D1, D2, ..., D4n) are disposed. The transducers and electrode plates are uniformly and alternately arranged adjacent to each other along the ring frame; where n is an integer greater than or equal to 1. The stimulation and imaging device further includes a time-sharing drive module, which is communicatively connected to the 4n electrode plates respectively, and is used to execute the excitation cycle; The excitation cycle includes starting from i=1 and incrementing sequentially to i=4n, controlling the i-th electrode plate Di to emit an excitation electrical signal, and simultaneously grounding the (i+2n)mod(4n)-th electrode plate D(i+2n)mod(4n) to form an excitation current loop; receiving the coupled acoustic signal through the (i+n-1)mod(4n)-th transducer H(i+n-1)mod(4n) and the (i+3n-1)mod(4n)-th transducer H(i+3n-1)mod(4n) to collect coupled acoustic signals from different directions; The signal processing module includes a multi-channel compression unit, which is communicatively connected to each of the transducers and is used to generate pulse compression signals in each direction based on the coupled acoustic signals in different directions. The image reconstruction module includes a spatial fusion unit, which is used to reconstruct the spatial distribution image of the sample under test based on the pulse compression signals in each direction.

5. The stimulation and imaging device according to claim 4, characterized in that, The time-sharing drive module is also used to repeatedly execute the excitation cycle m times; where m is an integer greater than or equal to 2; The multi-channel compression unit is also used to perform pulse compression on the coupled acoustic signals collected in the m excitation cycles for each direction, and obtain m sets of pulse compressed signals. The spatial fusion unit is also used to perform mean calculation on the m groups of pulse compression signals in each direction to obtain the average pulse compression signal in each direction, and reconstruct the spatial distribution image of the sample to be tested based on the average pulse compression signal.

6. The stimulation and imaging device according to claim 1, characterized in that, The direction of the stimulating magnetic field is parallel to the direction of the steady magnetic field; The stimulation magnetic field is also used to generate a second induced eddy current signal within the sample to be tested. The first induced eddy current signal and the second induced eddy current signal generate a coupled acoustic signal under the action of the steady magnetic field.

7. The stimulation and imaging device according to claim 6, characterized in that, The stimulation device is a stimulation coil; The stimulation coil is positioned on the side of the sample to be tested that is close to or away from the magnetic field generating device; the current path of the stimulation coil is perpendicular to the magnetic field direction of the steady magnetic field.

8. The stimulation and imaging device according to claim 1, characterized in that, The stimulation and imaging device also includes detection electrodes; The detection electrode is disposed on the organism where the sample to be tested is located. The detection electrode is used to acquire the electrophysiological signal generated by the sample to be tested in response to the stimulation magnetic field. The electrophysiological signal includes electrophysiological characteristic parameters.

9. The stimulation and imaging device according to claim 8, characterized in that, The signal processing module further includes an adjustment submodule, which is communicatively connected to the detection electrode. The adjustment submodule is used to compare the electrophysiological characteristic parameters with a preset threshold of the electrophysiological characteristic parameters and adjust the preset stimulation parameters according to the comparison result.

10. The stimulation and imaging device according to claim 1, characterized in that, The stimulation and imaging device also includes an excitation electrical signal source; The excitation electrical signal source includes a sequence generator and a signal generator; The sequence generator is used to generate the stimulus sequence; The signal generator is communicatively connected to the sequence generator and the electrode plate, respectively. The signal generator generates and sends the excitation electrical signal to the electrode plate based on the excitation sequence and the preset period signal.

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