Minimally invasive implantable brain-computer interface intracranial multi-mode signal monitoring system

Abstract

The invention relates to the technical field of medical treatment, and particularly discloses a minimally invasive implantable brain-computer interface intracranial multi-mode signal monitoring system, which comprises a flexible probe, a data acquisition module, a data return module and a data analysis module, the flexible probe is embedded into the high-precision microarray electrode and the sensor to collect neural signals in real time; the data acquisition module is used for synchronously acquiring electroencephalogram signals and intracranial pressure of specific parts of the brain; the data return module manages the collected data; and the data analysis module analyzes the electroencephalogram signal and the intracranial pressure data. According to the minimally invasive implantable brain-computer interface intracranial multi-mode signal monitoring system provided by the invention, lumbar puncture enters a cerebrospinal fluid space and is sent to a target spot, so that the infection risk can be effectively reduced, the limitation on the action of a patient is reduced, and the system has the characteristics of real-time performance, directness and accuracy; the method has very important significance and value for evaluating brain injury and brain functional lesion of a patient, prognosis judgment and the like.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, and in particular to a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system. Background Art

[0002] Brain-computer interfaces were originally created due to rehabilitation needs. Currently, there are four main medical application scenarios: First, for patients with limb movement disorders, rehabilitation brain-computer interfaces can repeatedly stimulate the brain to enhance the connection between neurons and achieve partial connection or functional repair; auxiliary brain-computer interfaces can control external devices after obtaining the patient's movement intention. Second, for patients with neurodevelopmental disorders, brain-computer interfaces identify electrophysiological abnormalities and provide non-drug treatment methods such as neurofeedback training. Third, for patients with mental illness, brain-computer interfaces analyze and judge emotional states in real time based on EEG signal characteristics, and monitor and intervene in the onset of the disease in a timely manner. Fourth, for patients with consciousness and cognitive disorders, brain-computer interfaces track patients' EEG signals and consciousness states in real time to assist in disease diagnosis and intervention plan design. With the development of technology, brain-computer interfaces are gradually moving towards diversified application scenarios such as disease diagnosis, treatment, and human enhancement.

[0003] The current implantable signal monitoring system is mainly an implantable brain-computer interface (iBCIs) system. iBCIs can record the electrical signals generated by brain activity and convert them into recognizable digital signals. According to the location where the electrodes are implanted or placed in the skull, iBCIs electrodes are divided into piercing and adhesive types. Among them, piercing electrodes can capture high-frequency neural signals (neural pulse signals and local field potential signals). This type of signal is suitable for neural substitutes, that is, it is necessary to obtain high-frequency brain signals for movement control and sensory feedback, and the required information can be extracted in a small area of ​​motor and sensory cortical areas. However, the intracortical electrode array currently used is inserted into the cerebral cortex through a sharp electrode needle tip, which is easy to cause varying degrees of damage and infection to the brain tissue; unlike piercing electrodes, adhesive electrodes are flexible electrodes that need to be attached to the surface of brain tissue (on the dura mater and below the dura mater). The collected signals come from the electric field fluctuations reflected in the cerebral cortex by the activity of neuronal groups. The core principle of this technology uses the changes in electric fields generated by brain activity. Electrodes can sensitively capture these tiny electric field fluctuations, namely electrocorticography (ECoG) signals. The current micrometer-scale cortical microelectrodes (μECoG) have high-density microelectrode arrays that can accurately capture the precise activities of the brain. At the same time, their excellent mechanical flexibility and electrochemical stability ensure long-term reliable operation, while good biocompatibility reduces the risk of immune response and inflammation.

[0004] The development of wireless implantable sensors provides a promising solution for intracranial monitoring. Current wireless implantable sensors are mainly used to monitor pressure, flow rate, temperature and pH in the human body. However, a multimodal disease monitoring system for EEG monitoring and intracranial pressure monitoring has not yet been invented.

[0005] Therefore, it is very necessary to propose a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system. The brain and spinal cord share the cerebrospinal fluid system, and the two are connected. Using lumbar puncture, a probe equipped with flexible electrodes and sensors can be sent into the cerebrospinal fluid, and the sensor can be navigated from the subarachnoid space of the spine into the ventricle to the designated area to be monitored. The entire process only requires a small skin puncture operation to complete the system delivery, and the surgical risk is extremely low. Summary of the invention

[0006] In view of the above-mentioned problems in the prior art, the present invention provides a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, which can effectively monitor and collect the patient's intracranial electroencephalogram and intracranial pressure. The system has the characteristics of real-time, directness and accuracy, and can further evaluate the patient's brain damage, brain functional lesions and prognosis, effectively ensuring patient safety.

[0007] To achieve the above-mentioned objectives, the present invention proposes a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, which includes a flexible probe, a data acquisition module, a data feedback module and a data analysis module; the flexible probe is embedded with high-precision microarray electrodes and sensors to perform real-time acquisition of neural signals; the data acquisition module synchronously acquires EEG signals and intracranial pressure in specific parts of the brain; the data feedback module manages the acquired data; and the data analysis module analyzes EEG signals and intracranial pressure data.

[0008] Preferably, the flexible probe is equipped with an RFID electronic tag, a flexible microelectrode array and a flexible sensor; and the flexible probe is powered by radio technology.

[0009] Preferably, the data acquisition module includes an EEG acquisition module and a flexible sensor; the EEG acquisition module uses a 32-channel ECoG electrode and a CINESIC32 ASIC amplifier; and the flexible sensor uses a bioabsorbable piezoresistive sensor.

[0010] Preferably, the CINESIC32 ASIC amplifier is manufactured using AMS 0.35µm CMOS technology and has a surface length of 89mm²; the CINESIC32 is capable of recording selectable gain and selectable frequency on any electrode combination in its 32 channels and transmitting 12-bit digital data to a microcontroller via an SPI link; the CINESIC32 consists of a programmable analog low-pass filter and a digital low-pass FIR filter for each channel and provides access to 32 recording electrodes.

[0011] Preferably, the frequency band of maximum gain is [0.5 Hz-300 Hz], and when the sampling frequency is 976 Hz, the collected data is less than 0.7 µVRMS of the input reference noise.

[0012] Preferably, the bioabsorbable piezoresistive sensor uses the bending strain of the piezoresistive response of the single-crystal silicon nanofilm system as a sensing element, and uses polylactic acid-glycolic acid copolymer as an adhesive layer on the upper and lower layers of the sensing element to bond the components together to form a sealed structure.

[0013] Preferably, the data return module is completed by an RFID reader / writer, and wirelessly communicates with the RFID electronic tag through an antenna; the RFID reader / writer is composed of three parts: a radio frequency module, a control processing module and an antenna.

[0014] Preferably, the data analysis module decodes and analyzes the EEG data recorded by ECoG electrodes and amplified by CINESIC32 ASIC amplifier and then transmitted to the computer through the reader / writer, and divides the ECoG signal into frequency bands; the data analysis module analyzes the intracranial pressure according to the corresponding indicators.

[0015] Preferably, the frequency bands of the ECoG signal are composed of delta wave, theta wave, alpha wave, beta wave, gamma wave and high gamma wave; the indicators include the pressure reactivity index PRx, ICP pulse amplitude AMP / average ICP wave amplitude and the correlation coefficient between AMP and the average pressure index.

[0016] Preferably, the application process of the system is as follows: S1, the patient lies sideways or sits with the back bent to expose the lumbar intervertebral space; S2. Medical staff disinfect the skin and perform local anesthesia on the puncture site under strict aseptic conditions; S3. When puncturing, select the L3-L4 or L4-L5 lumbar intervertebral space, insert a highly flexible microcatheter into the lumbar puncture needle and slowly pass through the skin, ligaments and dura mater until it enters the subarachnoid space. S4. Slowly remove the lumbar puncture needle and leave the catheter in place as a navigation path for the subsequent flexible probe.

[0017] Therefore, the present invention proposes a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, which has the following beneficial effects: (1) The present invention provides a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, which can enter the cerebrospinal fluid space and be delivered to the target point through lumbar puncture, which can effectively reduce the risk of infection and reduce restrictions on the patient's movements. It can collect intracranial electroencephalogram and intracranial pressure in real time and perform electrical signal and brain circulation dynamics analysis.

[0018] (2) The present invention provides a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, which has the characteristics of real-time, directness and accuracy, and is of great significance and value in evaluating patients' brain damage, functional brain lesions and prognosis.

[0019] (3) The present invention provides a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, which provides more information for analyzing the brain neural circuit mechanism of diseases through high-throughput neural recording.

[0020] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is an overall framework diagram of a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system of the present invention; Figure 2 It is a schematic diagram of the application process of a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system of the present invention; Figure 3 It is a schematic diagram of an electroencephalogram acquisition module of a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system of the present invention; Figure 4 It is a schematic diagram of a reader / writer module of an electroencephalogram acquisition module of a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system of the present invention; DETAILED DESCRIPTION

[0022] In order to make the technical solutions, advantages and purposes of the present invention clearer, the technical solutions of the embodiments of the present invention are clearly and completely described below. The described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of this application.

[0023] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0024] like Figure 1As shown, the present invention provides a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, which includes a flexible probe, a data acquisition module, a data feedback module and a data analysis module.

[0025] The flexible probe is equipped with RFID electronic tags, flexible microelectrode arrays and flexible sensors, and is powered by radio technology. It is embedded with high-precision microarray electrodes and sensors for real-time collection of neural signals. The data acquisition module completes the synchronous collection of EEG signals and intracranial pressure in specific parts of the brain and receives data from external devices, skin, and tissues. The data feedback module is completed through the RFID reader / writer, and wireless communication with the RFID electronic tag is carried out through the antenna to realize the writing operation of the tag memory data. The data analysis module receives the collected and processed data, performs data analysis on the EEG signals and intracranial pressure data, and completes the diagnosis and prognosis evaluation of the patient.

[0026] Among them, RFID electronic tags are a contactless automatic identification and data storage method with advantages such as data on the tag can be encrypted and larger data storage capacity; flexible microelectrode arrays and sensors can complete signal monitoring of specific parts of the brain and store real-time data in RFID electronic tags; flexible probes have good biocompatibility and stability, effectively reducing the risk of infection and potential complications.

[0027] like Figure 2 As shown, the present invention provides an application process of a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, and the steps are as follows: S1, the patient lies sideways or sits with the back bent to expose the lumbar intervertebral space; S2. Medical staff disinfect the skin and perform local anesthesia on the puncture site under strict aseptic conditions; S3. When puncturing, select the L3-L4 or L4-L5 lumbar intervertebral space, insert a highly flexible microcatheter into the lumbar puncture needle and slowly pass through the skin, ligaments and dura mater until it enters the subarachnoid space. S4. Slowly remove the lumbar puncture needle and leave the catheter in place as a navigation path for the subsequent flexible probe.

[0028] The data acquisition module includes an EEG acquisition module and a flexible sensor, and synchronously acquires EEG signals and intracranial pressure in specific parts of the brain.

[0029] like Figure 3As shown, the present invention provides an EEG acquisition module for a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system. The EEG acquisition module uses 32-channel ECoG electrodes and a CINESIC32 ASIC amplifier. Among them, the CINESIC32 ASIC is a low-power, low-noise amplifier specially designed for ECoG recording and taking into account the limitations of implantable applications. The CINESIC32 ASIC amplifier is manufactured using the AMS 0.35µm CMOS process and has a surface length of 89mm².

[0030] The main feature of CINESIC32 is the ability to record selectable gain as well as selectable frequency on any electrode combination among its 32 channels and transmit the 12-bit digital data to a microcontroller via an SPI link.

[0031] CINESIC32 consists of a programmable analog low-pass filter and a digital low-pass FIR filter for each channel, and provides access to 32 recording electrodes. The maximum gain of the amplifier is in the frequency band [0.5Hz-300Hz], and when the sampling frequency is 976Hz, the collected data is less than 0.7µVRMS of the input-referred noise.

[0032] Its working process is: the cerebral cortical electrical signals are input into the ECoG electrodes, recorded by the ECoG electrodes and transmitted to the preamplifier, filtered by the bandpass filter, and further transmitted to the amplifier. Then, the 12-bit digital data is transmitted to the MCUCC2541 microcontroller through the 16-bit ADC analog multiplexer connected to the SPI link and saved in the radio frequency electronic tag.

[0033] The flexible sensor uses a bioabsorbable piezoresistive sensor. The bioabsorbable piezoresistive sensor uses the bending strain of the piezoresistive response of the single-crystal silicon nanofilm system as the sensing element, and uses polylactic acid-glycolic acid copolymer (PLGA) as the bonding layer on the upper and lower layers of the sensing element to bond the components together to form a sealed structure.

[0034] The data transmission module is completed through the RFID reader and writer, and wireless communication is carried out with the RFID electronic tag through the antenna.

[0035] like Figure 4 As shown, the present invention provides a reader / writer module of a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system. The RFID reader / writer consists of three parts: a radio frequency module, a control processing module and an antenna.

[0036] The data analysis module decodes and analyzes the EEG data recorded by ECoG electrodes and amplified by CINESIC32 ASIC amplifier and then transmitted to the computer through the reader / writer, and divides the ECoG signal into frequency bands; the data analysis module analyzes the intracranial pressure according to the corresponding indicators.

[0037] Since ECoG signals are not affected by the skull, they have a higher signal-to-noise ratio than common scalp electroencephalogram (EEG). Therefore, ECoG signals are divided into multiple frequency bands for different neuroscience research and clinical applications.

[0038] The frequency bands of ECoG signals are divided into delta waves (0.1~4Hz), theta waves (4~8Hz), alpha waves (8~13Hz), beta waves (13~25Hz), gamma waves (25~80Hz) and high gamma waves (80~200Hz).

[0039] Among them, delta waves (0.1-4 Hz) may be related to deep sleep or certain pathological states; theta waves (4-8 Hz) are related to relaxation, meditation or certain cognitive processes; alpha waves (8-13 Hz) are related to the state of relaxation with eyes closed; beta waves (13-25 Hz) are related to wakefulness, concentration or certain motor activities; the gamma wave (25-80 Hz) frequency band may contain a variety of different neural activity patterns and is related to cognitive processes; high gamma waves (80-200 Hz) may be related to fine motor control or sensory processing. Each frequency band of EEG signals carries specific functional information, which provides the decoder with the ability to capture multi-dimensional features of behavioral tasks.

[0040] The indices included pressure reactivity index (PRx), ICP pulse amplitude (AMP) / mean ICP wave amplitude (MWA), and the correlation coefficient (R) between AMP (A) and mean pressure (P) (RAP) index.

[0041] Among them, the pressure reactivity index (PRx) is a physiological parameter used to evaluate cerebrovascular reactivity. It quantifies the brain's ability to regulate cerebral blood flow in response to ICP changes by analyzing the correlation between ICP and arterial blood pressure (ABP) waveforms. A positive PRx indicates impaired cerebrovascular reactivity, while a negative value indicates intact autoregulation. PRx monitoring provides real-time information about brain autoregulation, which helps guide treatment decisions.

[0042] ICP pulse amplitude (AMP) / mean ICP wave amplitude (MWA): used to assess brain autoregulation.

[0043] Correlation coefficient (R) between AMP (A) and average pressure (P) (RAP) index: The RAP index is a coefficient that reflects the correlation between the average ICP and the amplitude of the ICP waveform over a short period of time. An index close to 0 indicates that ICP can increase while maintaining an effective state of pressure-volume compensation. RAP values ​​close to +1 indicate that minimal volume changes will produce significant pressure differences or no pressure changes will occur. As ICP continues to increase, the amplitude (AMP) decreases. In this case, the RAP index approaches a negative value close to -1.

[0044] Therefore, the present invention provides a minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system. The entire process only requires a small skin puncture operation to complete the system delivery. The surgical risk is extremely low. The patient's intracranial EEG and intracranial pressure can be effectively monitored and collected. The system is real-time, direct and accurate, and can further evaluate the patient's brain damage, brain functional lesions and prognosis, effectively ensuring patient safety.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system, characterized in that: The system includes a flexible probe, a data acquisition module, a data feedback module and a data analysis module; the flexible probe is embedded with high-precision microarray electrodes and sensors to collect neural signals in real time; the data acquisition module synchronously collects EEG signals and intracranial pressure in specific parts of the brain; the data feedback module manages the collected data; and the data analysis module analyzes EEG signals and intracranial pressure data.

2. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 1, characterized in that: The flexible probe is equipped with an RFID electronic tag, a flexible microelectrode array and a flexible sensor; the flexible probe is powered by radio technology.

3. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 1, characterized in that: The data acquisition module includes an EEG acquisition module and a flexible sensor; the EEG acquisition module adopts a 32-channel ECoG electrode and a CINESIC32 ASIC amplifier; and the flexible sensor uses a bioabsorbable piezoresistive sensor.

4. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 3 is characterized in that: The CINESIC32 ASIC amplifier is fabricated in AMS 0.35µm CMOS technology and has a surface length of 89mm²; the CINESIC32 is able to record selectable gain and selectable frequency on any electrode combination in its 32 channels and transmit 12-bit digital data to a microcontroller via an SPI link; the CINESIC32 consists of a programmable analog low-pass filter and a digital low-pass FIR filter for each channel and provides access to 32 recording electrodes.

5. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 4, characterized in that: The frequency band of maximum gain is [0.5Hz-300Hz], and when the sampling frequency is 976Hz, the collected data is less than 0.7µVRMS of the input referred noise.

6. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 3, characterized in that: The bioabsorbable piezoresistive sensor uses the bending strain of the piezoresistive response of the single-crystal silicon nanofilm system as a sensing element, and uses polylactic acid-glycolic acid copolymer as an adhesive layer on the upper and lower layers of the sensing element to bond the components together to form a sealed structure.

7. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 1, characterized in that: The data return module is completed by the RFID reader / writer, and wireless communication with the RFID electronic tag is carried out through the antenna; the RFID reader / writer is composed of three parts: a radio frequency module, a control processing module and an antenna.

8. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 1, characterized in that: The data analysis module decodes and analyzes the EEG data recorded by ECoG electrodes and amplified by CINESIC32 ASIC amplifier and then transmitted to the computer through the reader / writer, and divides the ECoG signal into frequency bands; the data analysis module analyzes the intracranial pressure according to the corresponding indicators.

9. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 8, characterized in that: The frequency bands of the ECoG signal are composed of delta wave, theta wave, alpha wave, beta wave, gamma wave and high gamma wave; the indicators include pressure reactivity index PRx, ICP pulse amplitude AMP / average ICP wave amplitude and the correlation coefficient between AMP and average pressure index.

10. The minimally invasive implantable brain-computer interface intracranial multimodal signal monitoring system according to claim 1, characterized in that: The application process of the system is as follows: S1, the patient lies sideways or sits with the back bent to expose the lumbar intervertebral space; S2. Medical staff disinfect the skin and perform local anesthesia on the puncture site under strict aseptic conditions; S3. When puncturing, select the L3-L4 or L4-L5 lumbar intervertebral space, insert a highly flexible microcatheter into the lumbar puncture needle and slowly pass through the skin, ligaments and dura mater until it enters the subarachnoid space. S4. Slowly remove the lumbar puncture needle and leave the catheter in place as a navigation path for the subsequent flexible probe.

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