Cerebral blood flow synchronous array coil system and cerebral blood flow detection method

Abstract

The embodiment of the invention provides a cerebral blood flow synchronous array coil system and a cerebral blood flow detection method, and belongs to the technical field of magnetic resonance imaging. The device comprises a controller, a radio frequency power amplifier, a neck coil, a signal source and a coil connector, the controller is used for receiving a first enable signal generated by the MRI equipment cabinet, generating a second enable signal and triggering the neck coil and the matched radio frequency power amplifier to synchronously enter a working state; the signal source is used for providing a second radio frequency pulse; after receiving the second enable signal, the radio frequency power amplifier enters a working state, amplifies a second radio frequency pulse and sends the amplified second radio frequency pulse to the neck coil; the neck coil receives the second radio frequency pulse and is used for applying a pulse signal to a neck area and receiving a second enable signal to enter a working state; the coil connector is used for signal transmission between execution components. According to the embodiment, the accuracy and efficiency of cerebral blood flow detection of the experimental subject can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetic resonance imaging, and in particular to a cerebral blood flow synchronous array coil system and a cerebral blood flow detection method. BACKGROUND

[0002] The brain of human and animal has a complex nervous system, when the nervous system of the brain ages or is damaged, it will cause disorders such as blood transport, nutrient uptake and metabolism (such as the cerebral blood flow of the elderly or people with carotid artery stenosis is significantly different from that of normal people). In the related art, when a traditional coil is used to obtain cerebral blood flow imaging, the effect is not ideal, mainly due to the following two points: 1. The radio frequency field generated by the traditional coil is relatively dispersed, and the labeling efficiency is low; 2. Due to reason 1, the traditional coil needs to use higher radio frequency power in the labeling stage, which has the risk of excessive accumulation of thermal effect (SAR value).

[0003] Therefore, the technical problems existing in the related art need to be improved. SUMMARY

[0004] The main purpose of the embodiments of the present application is to provide a cerebral blood flow synchronous array coil system and a cerebral blood flow detection method, which can improve the detection accuracy and efficiency of the cerebral blood flow of the experimental object while reducing the risk of local thermal effect accumulation.

[0005] To achieve the above-mentioned purpose, one aspect of the embodiments of the present application provides a cerebral blood flow synchronous array coil system, which comprises a controller, a radio frequency power amplifier, a neck coil, a signal source and a coil connector. The controller is used to receive a first enabling signal generated by an MRI device cabinet, generate a second enabling signal, and trigger the neck coil and the matched radio frequency power amplifier to enter a working state synchronously; The signal source is used to provide a second radio frequency pulse; The radio frequency power amplifier enters a working state after receiving the second enabling signal, amplifies the second radio frequency pulse and sends it into the neck coil; The neck coil receives the second radio frequency pulse and is used to apply a pulse signal to the neck region and enter a working state after receiving the second enabling signal; The coil connector is used to perform signal transmission between components.

[0006] In some embodiments, when the controller receives the first enabling signal generated by the MRI device cabinet, the second enabling signal is generated, and the second enabling signal triggers the neck coil and the radio frequency power amplifier to enter a working state synchronously; The signal source provides a second radio frequency pulse, which triggers the neck coil to emit a marking pulse to mark the carotid artery blood. The MRI equipment cabinet generates a first radio frequency pulse and a control signal; the control signal causes the brain array transmitting coil to enter the working state synchronously with the neck coil and the radio frequency power amplifier. After the second enable signal ends, the control signal causes the brain array transmitting coil to enter the detuned state and the brain array receiving coil to enter the working state; when the brain array transmitting coil is working, it receives the first radio frequency pulse and transmits a radio frequency pulse.

[0007] In some embodiments, the controller is further configured to trigger the neck coil, the radio frequency power amplifier, and the brain array transmit coil to enter a detuned state when a first enable signal generated by the MRI equipment cabinet is disconnected; The controller is also configured to output a second enable signal to the radio frequency power amplifier when it receives a first enable signal generated by the MRI equipment cabinet during the carotid artery blood labeling stage; the second enable signal is used to put the radio frequency power amplifier and the neck coil into a ready state.

[0008] In some embodiments, the neck coil includes a first decoupling circuit for electromagnetic isolation during non-operating phases.

[0009] To achieve the above objectives, another aspect of this application proposes a method for detecting cerebral blood flow, implemented using a cerebral blood flow synchronization array coil system as described above. The method includes the following steps: During the labeled sequence, the MRI equipment cabinet outputs a first enable signal to the controller to start the radio frequency power amplifier, signal source, and neck coil; The signal source is used to generate a second radio frequency pulse; the second radio frequency pulse is amplified and transmitted by the radio frequency power amplifier. The neck coil is activated using the second radio frequency pulse to apply a radio frequency signal to mark the arterial blood, thus completing the marking phase. After a preset time has elapsed since the marking phase is completed, the MRI equipment cabinet generates a first radio frequency pulse and a control signal. The first radio frequency pulse activates the brain array transmitting coil and applies a radio frequency signal to excite protons in the brain imaging region. When the first enable signal is turned off, the control signal causes the brain array transmitting coil to enter a detuned state and the brain array receiving coil to enter a working state, thereby obtaining a labeled image; During the control sequence operation, the MRI equipment cabinet no longer outputs the first enable signal to the controller and skips the marking phase; the MRI equipment cabinet generates a first radio frequency pulse and a control signal, the first radio frequency pulse triggers the brain array transmitting coil to emit radio frequency signals and puts it into working state; the control signal puts the brain array receiving coil into working state to acquire control images; Subtract the control image from the labeled image to eliminate static tissue signals and generate a perfusion-weighted image; Based on the perfusion-weighted images, calculations and analyses are performed to obtain cerebral blood flow detection information.

[0010] In some embodiments, the method further includes: acquiring pulse marking stage preparation data before activating the neck coil via a first enable signal; the acquisition of pulse marking stage preparation data includes: The MRI equipment cabinet outputs a first enable signal, a first radio frequency pulse, and a control signal. The controller receives the first enable signal and generates the second enable signal. The second radio frequency pulse is generated using a signal source; The second enable signal and the second RF pulse are received using an RF power amplifier to obtain RF power amplifier preparation data. The MRI equipment cabinet outputs control signals to the brain array transmitting coil and the brain array receiving coil, so that the brain array transmitting coil and the neck coil enter the working state synchronously. The neck coil is used to receive the second enable signal to obtain neck coil preparation data. Based on the analysis and prompts of the RF power amplifier preparation data and the neck coil preparation data, the pulse marking stage preparation data is obtained.

[0011] In some embodiments, the method further includes: activating the controller via a first enable signal, applying a second enable signal, and activating the neck coil and the radio frequency power amplifier respectively, so that the neck coil and the radio frequency power amplifier synchronously enter the working state; The signal source outputs a second radio frequency pulse, which is amplified and transmitted by the radio frequency power amplifier, causing the neck coil to emit a radio frequency signal to mark the blood. The MRI equipment cabinet emits a first radio frequency pulse and a control signal, which are transmitted to the brain array transmitting coil and the brain array receiving coil. The control signal causes the brain array transmitting coil and the neck coil to enter a synchronous working state. The brain array transmitting coil receives the first radio frequency pulse, transmits a radio frequency signal, and activates protons in the imaging region. When the first enable signal is disconnected, the neck coil and the brain array transmitting coil become detuned, and the control signal causes the brain array receiving coil to enter a working state, thereby obtaining a labeled image.

[0012] In some embodiments, the method further includes: causing the brain array transmitting coil to enter a detuned state and the brain array receiving coil to enter an operating state via the control signal, thereby acquiring magnetic resonance echoes, including: When the first enable signal is disconnected, the transmitting coil of the brain array transmitting and receiving coils is connected to the power supply, and the receiving coil of the brain array transmitting and receiving coils is connected to the preamplifier through a directional coupler. The duplexer switches the transmitting or receiving state according to the preset requirement data to obtain the magnetic resonance echo.

[0013] To achieve the above objectives, another aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method described above.

[0014] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer program product, including a computer program that, when executed by a processor, implements the aforementioned method.

[0015] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the methods described above.

[0016] The embodiments of this application include at least the following beneficial effects: This application provides a cerebral blood flow synchronous array coil system, a cerebral blood flow detection method, an electronic device, a storage medium, and a program product. The solution includes: a controller, a radio frequency power amplifier, a neck coil, a signal source, and a coil connector. The controller receives a first enable signal generated by the MRI equipment cabinet, generates a second enable signal, and triggers the neck coil and its associated radio frequency power amplifier to synchronously enter a working state. The signal source provides a second radio frequency pulse. After receiving the second enable signal, the radio frequency power amplifier enters a working state, amplifies the second radio frequency pulse, and sends it to the neck coil. The neck coil receives the second radio frequency pulse and applies a pulse signal to the neck region, and enters a working state upon receiving the second enable signal. The coil connector is used for signal transmission between components. The embodiments of this application can improve the accuracy and efficiency of cerebral blood flow detection in experimental subjects. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the cerebral blood flow synchronization array coil system provided in the embodiments of this application; Figure 2 This is an ASL sequence timing diagram of the cerebral blood flow synchronization array coil system provided in the embodiments of this application; Figure 3 This is a logic control diagram of the cerebral blood flow synchronization array coil system provided in the embodiments of this application; Figure 4 This is a schematic diagram of the cerebral blood flow synchronization array coil system provided in the embodiments of this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0019] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”

[0020] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit the scope of this application.

[0022] Before providing a detailed description of the embodiments of this application, some of the nouns and terms involved in the embodiments of this application will be explained first. The nouns and terms involved in the embodiments of this application are subject to the following interpretations.

[0023] 1) MRI (Magnetic Resonance Imaging); 2) PMOS (P-channel Metal-Oxide-Semiconductor), a type of field-effect transistor used to control the power supply to the emitter coils of a brain array; 3) SAR (Specific Absorption Rate) measures the rate at which radio frequency energy is absorbed by biological tissues; 4) ASL (Arterial Spin Labeling); 5) RF (Radio Frequency); 6) ADC (Analog-to-Digital Converter); 7) G (Gradient), gradient magnetic field; 8) Gss (Slice Selection Gradient); 9) Gpe (Phase Encoding Gradient); 10) Gro (Readout Gradient): Reads out the gradient; 11) EPI (Echo Planar Imaging); 12) GRASE (Gradient and Spin Echo) imaging; 13) PLD (Post Labeling Delay).

[0024] Obtaining cerebral blood flow data using coils primarily involves two aspects: labeling carotid artery blood and detecting signals in brain imaging regions. However, the results of using traditional coils for cerebral blood flow imaging are not ideal, mainly due to the following two reasons: 1. The radio frequency field generated by traditional coils is relatively dispersed, resulting in low labeling efficiency; 2. Due to the wide labeling range, traditional coils generate high radio frequency power during the labeling stage, posing a risk of excessively high thermal effects (SAR values). Therefore, to solve these problems, it is necessary to design a cerebral blood flow synchronous array coil with adaptability, electromagnetic compatibility, and high sensitivity. Through a split design and intelligent collaborative control technology, the accuracy and efficiency of cerebral blood flow detection in experimental subjects can be significantly improved.

[0025] This invention belongs to the fields of biomedical engineering and magnetic resonance imaging technology, specifically relating to an arterial spin labeling (ASL) magnetic resonance coil system (cerebral blood flow synchronous array coil system) dedicated to monitoring cerebral blood flow perfusion. This technical solution achieves high-precision quantitative detection of cerebral blood flow through a split-type radio frequency coil design and intelligent collaborative control, meeting the needs of assessing blood perfusion in animal or human brains in various scenarios such as scientific research and clinical practice.

[0026] This study utilizes a brain blood flow synchronous array coil system to detect cerebral blood flow in experimental subjects via MRI, quantifying hemodynamic parameters. Combined with functional imaging techniques, this provides multi-dimensional scientific evidence for understanding the physiological mechanisms, pathological changes, and therapeutic effects of brain function. The proposed scheme employs a split-type radiofrequency coil design and intelligent collaborative control. First, a cervical marking coil precisely applies radiofrequency pulses to mark the carotid artery blood flow, and the brain's transmitting coil emits radiofrequency signals to activate protons in the imaging area. Then, the brain array receiving coil receives the signals to obtain a marked image. Next, the brain array transmitting coil emits radiofrequency pulses to activate protons in the imaging area, and the brain array receiving coil receives the signals to obtain a control image. Post-processing is then performed to generate perfusion-weighted images.

[0027] This application embodiment designs the integrated coil as a split-type radio frequency coil design device. This setup mainly consists of two parts: a neck coil and a brain array transmitting and receiving coil. First, the neck coil incorporates a decoupling circuit, and the driving unit is driven by an external radio frequency amplifier. The radio frequency power is controlled by a custom hardware unit to ensure accurate application of the labeling pulses. The brain array transmitting and receiving coils employ a phased array multi-channel radio frequency coil, optimized for the anatomical structure of most experimental subjects, ensuring uniformity and high sensitivity of the received signal. Built-in preamplifiers and active decoupling circuits ensure high sensitivity and improve the image signal-to-noise ratio. Furthermore, dynamic impedance matching is achieved through variable capacitors to ensure stable signal reception.

[0028] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0029] On one hand, embodiments of the present invention provide a cerebral blood flow synchronization array coil system, with reference to Figure 1 The system includes a controller, an RF power amplifier, a neck coil, a signal source, and a coil connector; The controller is used to receive the first enable signal generated by the MRI equipment cabinet, generate the second enable signal, and trigger the neck coil and the matching radio frequency power amplifier to enter the working state synchronously. The signal source is used to provide the second radio frequency pulse; After receiving the second enable signal, the RF power amplifier enters the working state and amplifies the second RF pulse before sending it to the neck coil. The neck coil receives a second radio frequency pulse and is used to apply a pulse signal to the neck region, and receives a second enable signal to enter the working state; Coil connectors are used to perform signal transmission between components.

[0030] Furthermore, the system also includes an MRI equipment cabinet and a separate radio frequency coil assembly; The split-type radio frequency coil assembly includes a neck coil, a brain array transmitting and receiving coil; The MRI equipment cabinet is used to generate a first enable signal, a first radio frequency pulse, and a control signal. The first enable signal triggers the controller to operate, the first radio frequency pulse triggers the brain array transmitting coil to transmit radio frequency pulses, and the control signal controls the brain array transmitting coil and the neck coil to enter the working state synchronously. The controller is used to receive a first enable signal and generate a second enable signal. The second enable signal triggers the neck coil and the radio frequency power amplifier to enter the working state synchronously. The radio frequency power amplifier is used to amplify and transmit radio frequency pulses. The neck coil is used to apply radio frequency pulses to the neck region. The signal source is used to provide the second radio frequency pulse. The brain array transmitting and receiving coils are used to transmit radio frequency pulses, receive signals, and generate brain perfusion images.

[0031] Furthermore, in the brain blood flow synchronization array coil system of this embodiment, the MRI equipment cabinet can be used to generate timing signals, such as enable signals, which can coordinate the marking and imaging stages of the split coils and avoid signal conflicts. The enable signal is used to trigger or disable the working state of specific components in the system (such as neck coils, brain array transmitting and receiving coils, and radio frequency amplifiers). Its core function is to coordinate time-division operation, allowing each component to work according to a strict timing sequence and avoiding conflicts.

[0032] The controller can interpret the instructions from the MRI equipment cabinet, control the switching of the radio frequency amplifier and coil states, and achieve physical isolation between the neck marker and brain imaging by controlling the enable signal, thereby reducing electromagnetic interference.

[0033] The power of the radio frequency power amplifier is adjustable to suit different experimental subjects, such as mice or monkeys; the radio frequency power amplifier can achieve localized and efficient labeling and avoid the risk of tissue overheating.

[0034] The neck coil is aligned with the carotid artery, reducing the marking area to 1 / 3 of that of a traditional coil, thus improving marking efficiency.

[0035] The brain array transmit and receive coils use a multi-channel phased array to cover the entire brain region, improving the signal-to-noise ratio.

[0036] The signal source provides a reference radio frequency signal, which synchronizes the coil with the main magnetic field and reduces image artifacts.

[0037] In some embodiments, when the controller receives a first enable signal generated by the MRI equipment cabinet, it generates a second enable signal and triggers the neck coil and radio frequency power amplifier to synchronously enter the working state. The signal source provides a second radio frequency pulse, which triggers the neck coil to emit a marking pulse to mark the carotid artery blood. The MRI equipment cabinet generates a first radio frequency pulse and a control signal. The control signal causes the brain array transmitting coil, neck coil, and radio frequency power amplifier to enter the working state synchronously. After the second enable signal ends, the control signal causes the brain array transmitting coil to enter the detuned state, and the brain array receiving coil enters the working state. When the brain array transmitting coil is working, it receives the first radio frequency pulse and transmits a radio frequency pulse.

[0038] Specifically, the controller is also used to generate a second enable signal when the first enable signal is received, which triggers the neck coil and the RF power amplifier to enter the working state synchronously through amplification and conduction by electrical components.

[0039] In some embodiments, the controller is also configured to trigger the neck coil, radio frequency power amplifier, and brain array transmit coil to enter a detuned state when the first enable signal generated by the MRI equipment cabinet is disconnected; The controller is also used to output a second enable signal to the radio frequency power amplifier when it receives a first enable signal generated by the MRI equipment cabinet during the carotid artery blood labeling stage; the second enable signal is used to put the radio frequency power amplifier and the neck coil into a ready state.

[0040] In some embodiments, the neck coil includes a first decoupling circuit for electromagnetic isolation during non-operating phases.

[0041] Furthermore, the brain array transmitting and receiving coils in this invention employ a phased array multi-channel radio frequency coil design; The brain array transmit and receive coils incorporate a preamplifier, a second decoupling circuit, and a variable capacitor; the preamplifier is used to improve the image signal-to-noise ratio; the second decoupling circuit is used to force the coils to detune during non-operational periods to prevent crosstalk; and the variable capacitor is used to dynamically adjust the coil impedance.

[0042] Furthermore, the brain array's transmitting and receiving coils are adapted to different experimental subjects using variable capacitors to reduce signal attenuation.

[0043] The brain array's transmit and receive coils also use duplexers and directional couplers: automatically switching between transmit and receive states, protecting the preamplifier, and improving signal fidelity.

[0044] On the other hand, embodiments of the present invention also provide a method for detecting cerebral blood flow, which is implemented using the cerebral blood flow synchronous array coil system as described above. The method includes the following steps: In step S100, during the operation of the labeled sequence, the MRI equipment cabinet outputs a first enable signal to the controller to start the radio frequency power amplifier, signal source and neck coil; Step S200: A second radio frequency pulse is generated using a signal source; the second radio frequency pulse is amplified and transmitted by a radio frequency power amplifier; Step S300: Activate the neck coil with a second radio frequency pulse to apply a radio frequency signal to mark the arterial blood, thus completing the marking stage; After a preset time has elapsed since the completion of step S400 and the marking phase, the MRI equipment cabinet generates a first radio frequency pulse and a control signal. The first radio frequency pulse activates the brain array transmitting coil and applies a radio frequency signal to excite protons in the brain imaging region. Step S500: When the first enable signal is turned off, the control signal causes the brain array transmitting coil to enter a detuned state and the brain array receiving coil to enter a working state, thereby obtaining a labeled image. In step S600, during the operation of the control sequence, the MRI equipment cabinet no longer outputs the first enable signal to the controller and skips the marking stage; the MRI equipment cabinet generates a first radio frequency pulse and a control signal. The first radio frequency pulse triggers the brain array transmitting coil to emit radio frequency signals and puts it into working state; the control signal puts the brain array receiving coil into working state and acquires control images. Step S700: Subtract the control image from the labeled image to eliminate static tissue signals and generate a perfusion-weighted image; Step S800: Perform calculation and analysis based on the perfusion-weighted image to obtain cerebral blood flow detection information.

[0045] Specifically, in steps S100-S800, the MRI equipment cabinet, controller, radio frequency power amplifier, neck coil, signal source, and brain array transmitting and receiving coils are connected via coil connectors; The MRI equipment cabinet generates a first enable signal, which is transmitted to the controller to generate a second enable signal, causing the radio frequency power amplifier and the neck coil to enter the working state synchronously. The MRI equipment cabinet disconnects the first enable signal, and the neck coil enters the detuned state. The signal source provides a second radio frequency pulse, which is amplified and transmitted by the radio frequency power amplifier, causing the neck coil to emit radio frequency pulses to mark arterial blood. The MRI equipment cabinet generates a first radio frequency pulse and a control signal. The first radio frequency pulse causes the brain array transmitting coil to enter the transmitting pulse signal. The control signal controls the brain array transmitting coil and the neck coil to enter the working and detuning synchronously, and controls the switching of the brain array transmitting coil and the brain array receiving coil to obtain labeled images.

[0046] The MRI equipment cabinet generates a first radio frequency pulse and a control signal. The control signal causes the brain array transmitting coil to enter the working state. The brain array transmitting coil emits the first radio frequency pulse, which excites protons in the imaging area. The control signal switches the working state of the brain array coil, so that the brain array receiving coil can acquire the signal and obtain a control image. Based on the magnetic resonance echo, the labeled image is subtracted from the control image to eliminate static tissue signals and generate a perfusion-weighted image; Cerebral blood flow detection information is obtained by performing calculations and analysis based on perfusion-weighted images.

[0047] Specifically, after a preset time (post-labeling delay PLD) following the completion of the labeling phase, the MRI equipment cabinet generates a first radio frequency pulse and a control signal. The first radio frequency pulse activates the brain array transmitting coil, applying a radio frequency signal to excite protons in the brain imaging region. When the first enable signal is disconnected, the neck coil and radio frequency power amplifier enter a detuned state. The control signal causes the brain array transmitting coil to enter a detuned state, enabling the brain array receiving coil to enter the working state, thus obtaining the labeled image.

[0048] Furthermore, embodiments of the present invention can also combine M0-weighted images and perfusion signals to generate absolute cerebral blood flow parameters. Here, M0 represents the macroscopic magnetization intensity of hydrogen protons (water molecules) in a fully magnetized equilibrium state, which is related to the proton density of the tissue itself and MRI scan parameters. The M0-weighted image is an image acquired through long TR (repetition time) scanning, and its signal intensity directly reflects the equilibrium magnetization intensity (M0) of the tissue. The perfusion signal reflects the local hemodynamic information after the labeled arterial blood reaches the brain tissue. The absolute cerebral blood flow parameter is the blood flow rate through a unit volume of brain tissue per unit time. Embodiments of the present invention also provide human-computer interaction technology, which automatically completes the labeling, imaging, and signal processing processes through preset interactive logic, reducing human intervention errors. It can convert complex magnetic resonance echoes and parameters into intuitive charts or pseudo-color images, and can run self-test programs through the interactive interface to verify hardware status such as coil sensitivity and gradient linearity.

[0049] In some embodiments, the method of the present invention further includes: acquiring pulse marking stage preparation data before activating the neck coil via a first enable signal; acquiring the pulse marking stage preparation data includes: Step S010: Use the MRI equipment cabinet to output the first enable signal, the first radio frequency pulse, and the control signal; Step S020: Use the controller to receive the first enable signal and generate the second enable signal; Step S030: Use a signal source to generate a second radio frequency pulse; Step S040: Use the RF power amplifier to receive the second enable signal and the second RF pulse to obtain the RF power amplifier preparation data; Step S050: Use the MRI equipment cabinet to output control signals to the brain array transmitting coil and the brain array receiving coil, so that the brain array transmitting coil and the neck coil enter the working state synchronously. Step S060: Use the neck coil to receive the second enable signal and obtain neck coil preparation data; Step S070: Analyze and prompt based on the RF power amplifier preparation data and neck coil preparation data to obtain the pulse marking stage preparation data.

[0050] Furthermore, the radio frequency power amplifier preparation data in this embodiment includes a set of parameters required to drive the neck coil to transmit marking pulses, such as power value, frequency, pulse width, and timing instructions (marking start or end time). The non-resonant state information of the brain array transmitting and receiving coils in this embodiment is a forced detuning state feedback, displaying impedance changes during detuning to prevent the brain array coil from interfering with the neck marking process and ensure signal purity. The pulse marking stage preparation data in this embodiment is a ready instruction generated by integrating the radio frequency power amplifier and coil states, including amplifier ready flags, coil state confirmation, and safety verification results. This embodiment also includes a human-computer interaction prompt module that monitors the radio frequency power amplifier parameters and coil states, providing operation prompts, including audio prompts (voice reminders of preparation completion) and log recording (generating a preparation report containing timestamps and parameter information). Through integrated prompts, operators can quickly locate problems (e.g., if the coil is not detuned, the decoupling circuit needs to be checked).

[0051] In some embodiments, the method of the present invention further includes: Step S900: Activate the controller through the first enable signal, apply the second enable signal, and activate the neck coil and the RF power amplifier respectively, so that the neck coil and the RF power amplifier enter the working state synchronously. Step SA00: A second radio frequency pulse is output through the signal source. The second radio frequency pulse is amplified and transmitted by the radio frequency power amplifier, causing the neck coil to emit a radio frequency signal to mark the blood. Step SB00: The first radio frequency pulse and control signal are emitted through the MRI equipment cabinet and transmitted to the brain array transmitting coil and the brain array receiving coil, so that the control signal enables the brain array transmitting coil and the neck coil to enter the working state synchronously. The brain array transmitting coil receives the first radio frequency pulse, emits radio frequency signals, and activates protons in the imaging area. When the first enable signal is disconnected, the neck coil and the brain array transmitting coil are detuned, and the control signal enables the brain array receiving coil to enter the working state, thereby obtaining a labeled image.

[0052] Specifically, the method for obtaining a marked image disclosed in the embodiments of the present invention includes: The first enable signal is output from the MRI equipment cabinet and transmitted to the controller to obtain the second enable signal; Upon receiving the second enable signal, the RF power amplifier and neck coil synchronously enter the working state. The signal source generates a second radio frequency pulse. The second radio frequency signal is amplified and transmitted by radio frequency power, so that the neck coil applies a radio frequency signal to mark the arterial blood for a preset time. The MRI equipment cabinet generates control signals, which cause the brain array's transmit coil and neck coil to synchronously enter the working state; The MRI equipment cabinet generates a first radio frequency pulse, the brain array transmitting coil receives the first radio frequency pulse, and transmits a radio frequency pulse to mark protons in the imaging area; After the first enable signal ends, the control signal switches the working state of the brain array's transmitting and receiving coils, causing the transmitting coil of the brain array to detune and the receiving coil of the brain array to receive the signal, thus obtaining the labeled image.

[0053] The embodiments of the present invention also include: The first enable signal is output from the MRI equipment cabinet and transmitted to the controller to obtain the second enable signal; The neck coil receives the second enable and the second radio frequency pulse to enter the working state and mark arterial blood. When the first enable signal is turned off, the neck coil enters the detuned state.

[0054] The brain array receiving coil receives the first radio frequency second pulse, generating a radio frequency pulse that excites the hydrogen nuclei in the brain.

[0055] In some embodiments, the method of the present invention further includes: Step SC00: By controlling the signal, the brain array transmitting coil is detuned, and the brain array receiving coil is activated to acquire magnetic resonance echoes, including: Step SD00: Disconnect the first enable signal, connect the transmitting coil of the brain array transmitting and receiving coils to the power supply, and connect the receiving coil of the brain array transmitting and receiving coils to the preamplifier through a directional coupler. The duplexer switches the transmitting or receiving state according to the preset requirement data to obtain the magnetic resonance echo.

[0056] Specifically, in this embodiment of the invention, the first enable signal is disconnected, and the operation state of the brain array transmitting and receiving coils is switched to acquire magnetic resonance echoes, including: Disconnecting the first enable signal drives the PMOS to conduct, connecting the transmitting coil of the brain array's transmitting and receiving coils to the power supply, and connecting the receiving coil of the brain array's transmitting and receiving coils to the preamplifier through a directional coupler. The duplexer switches between transmitting and receiving states according to preset required data to obtain magnetic resonance echoes.

[0057] As an optional implementation, the ASL sequence timing diagram of the cerebral blood flow synchronization array coil in this embodiment of the invention is referenced. Figure 2 In this MRI model, RF stands for Radio Frequency, a high-frequency electromagnetic wave used to excite or detect hydrogen protons; RF1 is a labeling pulse emitted by a neck coil, used to selectively reverse the spin state of water molecules in carotid artery blood; RF2 is an excitation pulse emitted by the brain array's transmitting and receiving coils, used to flip the brain's hydrogen proton magnetization vector during imaging; ADC is an analog-to-digital converter, converting the analog perfusion signals received by the brain array's transmitting and receiving coils into digital signals for subsequent image reconstruction and quantitative analysis; G is a linear magnetic field used for spatial encoding in MRI, generated by a gradient coil; Gss1, in conjunction with the RF1 labeling pulse, defines the labeling range of carotid artery blood; Gss2, in conjunction with the RF2 excitation pulse, selects the brain imaging slice; Gpe1 is a gradient magnetic field used for phase encoding of the signal during the imaging phase; and Gro is a gradient magnetic field applied during signal acquisition (ADC phase) for frequency encoding. (Reference) Figure 3 In the g and h stages, Table 1 is the logic control table for the signals, which reflects the input of control signals: Table 1. Logic Control Table for Signals

[0058] As an optional implementation, the collaborative process of the cerebral blood flow synchronization array coil system in this embodiment of the invention includes: 1. Overall Logic Control a. such as Figure 3 As shown in the middle g stage, the MRI equipment cabinet sends a first enable signal to the controller. The first enable signal is amplified and conducted through electrical components, which enables the neck coil and the brain array transmitter coil to enter the working state respectively.

[0059] b. Figure 3 As shown in the middle h stage, the MRI equipment cabinet disconnects the first enable signal to the controller, causing the neck coil to enter a detuned state, and at the same time, the MRI equipment cabinet causes the brain array receiving coil to enter the working state.

[0060] 2. Carotid artery blood labeling stage The MRI equipment cabinet outputs a marker enable signal (first enable signal) to the controller. The controller then outputs a second enable signal to the RF power amplifier, putting the RF power amplifier into a ready state. Simultaneously, the MRI equipment cabinet outputs control signals to the brain array transmit and receive coils, putting the brain array transmit coil into an active state and the brain array receive coil into a detuned state. At this point, the system completes the pulse marking phase preparation.

[0061] The neck marking coil (neck coil) applies a marking pulse RF1 (power and time optimized in pre-experimentation) to the neck region to mark water molecules in the blood.

[0062] The first enable signal is disconnected, and the RF power amplifier is simultaneously deactivated from its ready state. At the same time, the controller outputs a detuning signal to the neck coil, putting the neck coil into a non-resonant state. The carotid artery blood labeling stage is now complete.

[0063] 3. Image Acquisition with Markers After applying the labeling pulse RF1, wait a few seconds (adjusted according to blood flow velocity, not exceeding 3 times the longitudinal relaxation time of the blood) to ensure that the labeled blood reaches the imaging area.

[0064] Signal readout: Acquire image information using an MRI sequence suitable for the experiment (e.g., 2D scan using an EPI sequence or 3D scan using a GRASE sequence).

[0065] 4. Image acquisition for comparison When acquiring control images, there is no need for a carotid artery labeling phase; the acquisition can be completed using the same sequence with the same parameters as the labeled images.

[0066] 5. M0 Weighted Image Acquisition When acquiring M0-weighted images, there is no need for a carotid artery labeling phase. Use the same sequence as the labeled images, and except for setting TR>4000 ms, other parameters can be the same as the labeled images to complete the acquisition.

[0067] 6. Post-processing The labeled image is subtracted from the control image to eliminate static tissue signals and generate a perfusion-weighted image.

[0068] Visualized reports are generated using techniques such as quantitative models and artifact calibration.

[0069] This invention presents a modular RF coil design, where the integrated coil is replaced with a separate design. This separate design allows for more precise marking of the marking area and improves marking efficiency.

[0070] The cerebral blood flow synchronous array coil system greatly improves marking efficiency through independent neck coil marking.

[0071] The low power of the neck coil marker prevents the SAR value from being too high and reduces the risk of thermal effects.

[0072] As an optional implementation method, refer to Figure 4 This embodiment includes: Phase A: Figure 4The MRI equipment cabinet a sends an enable signal a1 to the controller b. Controller b and signal source e send signals b2 and e1 to the radio frequency power amplifier c, respectively. The radio frequency power amplifier c and controller b send the amplified signal c1 and decoupling signal b1 to the neck coil d, which then completes carotid artery marking. Figure 2 The RF1 process in [the context of the original text].

[0073] Phase B: Figure 4 In the MRI equipment cabinet, enable signal a1 is disconnected, neck coil d enters detuned state, and brain array transmit and receive coils f enter radio frequency operating state. Correspondingly... Figure 2 The RF2 process in [the context of the original text].

[0074] Phase C: The brain array transmitting and receiving coil f receives the signal, and the brain array transmitting and receiving coil f enters the receiving state, corresponding to... Figure 2 The ADC process.

[0075] As an optional implementation, embodiments of the present invention include: like Figure 3 As shown, a brain blood flow synchronization array coil system for improving signal-to-noise ratio and reducing thermal effects includes a controller, a radio frequency power amplifier, a neck coil, a signal source, and a coil connector for transmitting signals.

[0076] The acquisition of cerebral blood flow data in monkeys using a cerebral blood flow synchronization array coil system mainly consists of the following two stages: The first stage is to output the first enable signal, corresponding to... Figure 2 Middle G stage: Signal trigger: The MRI equipment cabinet outputs the first enable signal and transmits it to the controller.

[0077] Labeling carotid artery blood: The controller transmits labeling and decoupling signals to the neck coil, which then emits radio frequency signals to label the arterial blood. Compared to traditional coils, the neck coil has a more concentrated radio frequency, achieving high labeling efficiency and lower SAR values ​​with lower power.

[0078] The second stage is to disconnect the first enable signal, corresponding to... Figure 2 Middle h stage; Brain activation: The PMOS is directly driven to turn on, the brain transmitting coil is connected to the power supply, and the receiving coil is connected to the preamplifier through a directional coupler. The duplexer automatically switches between transmitting and receiving states as needed for the experiment.

[0079] A good signal can be obtained by using a brain receiving coil.

[0080] As an optional implementation, embodiments of the present invention include: like Figure 3As shown, the primary operating mode of the neck coil is to label hydrogen molecules flowing in arterial blood. Before the experiment begins, the neck coil is properly positioned and placed on the subject. Typically, the center of the coil is aligned with the horizontal line connecting the two mandibles to ensure optimal scanning range.

[0081] The marking area of ​​the neck coil is significantly smaller than that of a conventional coil, but the marking efficiency is high, which improves the signal-to-noise ratio.

[0082] On the other hand, embodiments of the present invention also provide an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the aforementioned method.

[0083] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0084] Another embodiment of the hardware structure of the electronic device, the electronic device including: The processor can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to achieve the technical solutions provided in the embodiments of this application. The memory can be implemented in the form of read-only memory (ROM), static storage device, dynamic storage device, or random access memory (RAM). The memory can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory and called by the processor to execute the methods described in the embodiments of this application. Input / output interfaces are used to implement information input and output; The communication interface is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). A bus is used to transfer information between various components of a device, such as processors, memory, input / output interfaces, and communication interfaces. The processor, memory, input / output interfaces, and communication interfaces communicate with each other within the device via a bus.

[0085] On the other hand, embodiments of the present invention also provide a computer program product, including a computer program that, when executed by a processor, implements the aforementioned method.

[0086] It is understood that the content of the above method embodiments is applicable to the embodiments of this program product. The specific functions implemented by the embodiments of this program product are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0087] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0088] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.

[0089] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0090] The cerebral blood flow synchronous array coil system, cerebral blood flow detection method, electronic device, storage medium, and program product provided in this application achieve high-precision, low-risk cerebral blood flow perfusion detection through a split-type radio frequency coil design and intelligent collaborative control. By using radio frequency marking with a neck marking coil, the spin state of carotid artery blood is accurately reversed, solving the problems of large marking range and low efficiency in traditional coils. Dynamic impedance matching and phased array design of the multi-channel transmitting and receiving coils in the brain improve the signal-to-noise ratio and spatial resolution of the perfusion signal. Time-division control of the enable signal by the controller coordinates the working timing of the neck and brain array coils, avoiding electromagnetic interference.

[0091] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0092] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0093] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0094] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0095] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0096] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0097] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0098] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0099] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0100] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0101] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A cerebral blood flow synchronization array coil system, characterized in that, The system includes a controller, an RF power amplifier, a neck coil, a signal source, and a coil connector; The controller is used to receive a first enable signal generated by the MRI equipment cabinet, generate a second enable signal, and trigger the neck coil and its matching radio frequency power amplifier to enter the working state synchronously. The signal source is used to provide a second radio frequency pulse; After receiving the second enable signal, the radio frequency power amplifier enters the working state and amplifies the second radio frequency pulse before sending it to the neck coil. The neck coil receives the second radio frequency pulse and is used to apply a pulse signal to the neck region, and receives the second enable signal to enter the working state; The coil connector is used to perform signal transmission between components.

2. The system according to claim 1, characterized in that, When the controller receives the first enable signal generated by the MRI equipment cabinet, it generates a second enable signal and triggers the neck coil and the radio frequency power amplifier to synchronously enter the working state. The signal source provides a second radio frequency pulse, which triggers the neck coil to emit a marking pulse to mark the carotid artery blood. The MRI equipment cabinet generates a first radio frequency pulse and a control signal; the control signal causes the brain array transmitting coil, the neck coil, and the radio frequency power amplifier to enter the working state synchronously. After the second enable signal ends, the control signal causes the brain array transmitting coil to enter the detuned state, and the brain array receiving coil enters the working state; when the brain array transmitting coil is working, it receives the first radio frequency pulse and transmits a radio frequency pulse.

3. The system according to claim 2, characterized in that, The controller is also configured to trigger the neck coil, the radio frequency power amplifier, and the brain array transmitter coil to enter a detuned state when the first enable signal generated by the MRI equipment cabinet is disconnected; The controller is also configured to output a second enable signal to the radio frequency power amplifier when it receives a first enable signal generated by the MRI equipment cabinet during the carotid artery blood labeling stage; the second enable signal is used to put the radio frequency power amplifier and the neck coil into a ready state.

4. The system according to claim 1, characterized in that, The neck coil is provided with a first decoupling circuit, which is used for electromagnetic isolation during non-operating phases.

5. A method for detecting cerebral blood flow, implemented using a cerebral blood flow synchronous array coil system as described in any one of claims 1 to 4, characterized in that, The method includes the following steps: During the labeled sequence, the MRI equipment cabinet outputs a first enable signal to the controller to start the radio frequency power amplifier, signal source, and neck coil; The signal source is used to generate a second radio frequency pulse; the second radio frequency pulse is amplified and transmitted by the radio frequency power amplifier. The neck coil is activated using the second radio frequency pulse to apply a radio frequency signal to mark the arterial blood, thus completing the marking phase. After a preset time has elapsed since the marking phase is completed, the MRI equipment cabinet generates a first radio frequency pulse and a control signal. The first radio frequency pulse activates the brain array transmitting coil and applies a radio frequency signal to excite protons in the brain imaging region. When the first enable signal is turned off, the control signal causes the brain array transmitting coil to enter a detuned state and the brain array receiving coil to enter a working state, thereby obtaining a labeled image; During the control sequence operation, the MRI equipment cabinet no longer outputs the first enable signal to the controller and skips the marking phase; the MRI equipment cabinet generates a first radio frequency pulse and a control signal, the first radio frequency pulse triggers the brain array transmitting coil to emit radio frequency signals and puts it into working state; the control signal puts the brain array receiving coil into working state to acquire control images; Subtract the control image from the labeled image to eliminate static tissue signals and generate a perfusion-weighted image; Based on the perfusion-weighted images, calculations and analyses are performed to obtain cerebral blood flow detection information.

6. The method according to claim 5, characterized in that, The method further includes: acquiring pulse marking stage preparation data before activating the neck coil via a first enable signal; the acquisition of pulse marking stage preparation data includes: The MRI equipment cabinet outputs a first enable signal, a first radio frequency pulse, and a control signal. The controller receives the first enable signal and generates the second enable signal. The second radio frequency pulse is generated using a signal source; The second enable signal and the second RF pulse are received using an RF power amplifier to obtain RF power amplifier preparation data. The MRI equipment cabinet outputs control signals to the brain array transmitting coil and the brain array receiving coil, so that the brain array transmitting coil and the neck coil enter the working state synchronously. The neck coil is used to receive the second enable signal to obtain neck coil preparation data. Based on the analysis and prompts of the RF power amplifier preparation data and the neck coil preparation data, the pulse marking stage preparation data is obtained.

7. The method according to claim 5, characterized in that, The method further includes: activating the controller by a first enable signal, applying a second enable signal, activating the neck coil and the radio frequency power amplifier respectively, so that the neck coil and the radio frequency power amplifier enter the working state synchronously; The signal source outputs a second radio frequency pulse, which is amplified and transmitted by the radio frequency power amplifier, causing the neck coil to emit a radio frequency signal to mark the blood. The MRI equipment cabinet emits a first radio frequency pulse and a control signal, which are transmitted to the brain array transmitting coil and the brain array receiving coil. The control signal causes the brain array transmitting coil and the neck coil to enter a synchronous working state. The brain array transmitting coil receives the first radio frequency pulse, transmits a radio frequency signal, and activates protons in the imaging region. When the first enable signal is disconnected, the neck coil and the brain array transmitting coil become detuned, and the control signal causes the brain array receiving coil to enter a working state, thereby obtaining a labeled image.

8. The method according to claim 5, characterized in that, The method further includes: using the control signal to detune the brain array transmitting coil and activate the brain array receiving coil to acquire magnetic resonance echoes, including: When the first enable signal is disconnected, the transmitting coil of the brain array transmitting and receiving coils is connected to the power supply, and the receiving coil of the brain array transmitting and receiving coils is connected to the preamplifier through a directional coupler. The duplexer switches the transmitting or receiving state according to the preset requirement data to obtain the magnetic resonance echo.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the method of any one of claims 5 to 8.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 5 to 8.

Images