Interventional brain-computer interface system based on stent electrode

Abstract

The invention belongs to the technical field of brain-computer interfaces, and particularly relates to an interventional brain-computer interface system based on a stent electrode. The brain-computer interface system comprises a support electrode, a wire bundle and an in-vivo controller which are arranged in the body, and a wireless charger and a mobile terminal which are arranged in the body. The stent electrode comprises a stent skeleton, an electrode and a wire, and the stent electrode is implanted into a blood vessel near a brain target area through an internal jugular vein through an interventional operation. The electrodes are used for collecting electroencephalogram signals and conducting electrical stimulation on nearby brain areas. The controller collects electroencephalogram signals through the electrodes and sends the electroencephalogram signals to the in-vitro mobile terminal through wireless transmission, meanwhile, the brain area is electrically stimulated through the electrodes so as to treat diseases, and closed-loop regulation and control are achieved. The mobile terminal receives and decodes signals sent by the in-vivo controller, analyzes the signals to optimize and adjust stimulation parameters, and sends the stimulation parameters to the in-vivo controller to adjust a built-in stimulation strategy. The invention can realize minimal invasion, improve the signal quality and improve the treatment effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of brain-computer interfaces, and particularly relates to an invasive brain-computer interface system. Background Art

[0002] A brain-computer interface is a technology that establishes a communication and control channel between the brain and an external device, directly manipulates the external device with the brain's bioelectric signals, or regulates the brain's activities with external stimuli, thereby enhancing, improving, and extending the brain's functions. The implementation methods of brain-computer interfaces are mainly divided into three types - invasive, non-invasive, and invasive. Among them, invasive brain-computer interfaces are the mainstream of current research and have been widely applied. By collecting brain signals related to the limbs and obtaining motor intentions, the purpose of controlling prosthetics or machine-assisted devices can be achieved, such as brain-controlled wheelchairs [1] , a paralyzed patient controlling a robotic arm to complete an object grasping task [2] , driving a cursor to simulate keyboard input [3] and so on. Some researchers have also achieved the purpose of neuromodulation based on nerve stimulation. For example, the team of Professor Li Luming at Tsinghua University developed an implantable nerve stimulator for the treatment of Parkinson's patients based on deep brain stimulation (DBS), and achieved neuromodulation of patients through the local electric field located in the subthalamic nucleus [4] . However, invasive brain-computer interfaces usually require craniotomy to implant electrodes into the cerebral cortex or deep brain regions, which is likely to cause human rejection reactions; and the electrodes need to be in direct contact with brain tissue, and the electrode development technology is difficult and has a high technical barrier. Non-invasive brain-computer interfaces usually only need to wear an electroencephalogram (EEG) signal acquisition device on the scalp, which causes less harm to the human body and has a lower technical difficulty. At present, it has also been widely used in non-medical fields, especially in the entertainment and gaming industries [5] . However, the most obvious disadvantage of non-invasive brain-computer interfaces is that they are too far from the cerebral cortex, making it difficult to continuously, stably, and accurately capture EEG signals.

[0003] The invasive brain-computer interface, through a minimally invasive approach, punctures a small opening in the blood vessel and realizes brain-computer connection through a minimally invasive surgery similar to a cerebrovascular stent. It causes less harm to the human body than invasive ones, has higher signal acquisition quality than non-invasive ones, and can reach deep brain regions through the blood vessel network, bringing more possibilities for the subsequent development of brain-computer interface technology. Summary of the Invention

[0004] The purpose of the present invention is to provide an invasive brain-computer interface system based on stent electrodes, avoiding the disadvantages of large trauma caused by craniotomy for implanting electrodes in invasive brain-computer interfaces and the problem of low signal quality in non-invasive brain-computer interfaces.

[0005] The implantable brain-computer interface system based on a stent electrode provided by the present invention has a structure as shown in Figure 1, and includes a stent electrode 11, a wire bundle 12, and an in-vivo controller 13 in the in-vivo part, as well as a wireless charger 14 and a mobile terminal 15 in the ex-vivo part; the stent electrode 11 includes a stent framework 21, electrodes 22, and wires 23. The electrodes 22 are fixed on the stent framework 21 and insulated from the stent framework. The wires 23 run along the framework veins and converge into a bundle at the tail end, which is the wire bundle 12; the stent electrode 11 is implanted into the blood vessel near the target area of the brain (the specific area is determined according to the disease to be treated) through the internal jugular vein by an intervention technique; the stent framework 21 expands the blood vessel to ensure that the electrodes 22 are closely attached to the inner wall of the blood vessel and keep a relatively short distance from the brain area outside the blood vessel, thereby improving the signal quality; the electrodes 22 can be used to collect electroencephalogram signals and can also be used as stimulating electrodes to perform electrical stimulation on the nearby brain area; the wire bundle 12 passes through the blood vessel from the neck opening and is connected to the in-vivo controller 13 buried under the subcutaneous tissue of the chest; the in-vivo controller 13 can collect electroencephalogram signals through the electrodes 22 and perform analysis. On the one hand, the encoded signals are sent to the ex-vivo mobile terminal 15 through wireless transmission. On the other hand, a stimulation strategy can also be generated to perform electrical stimulation on the brain area through the electrodes 22 to treat diseases and achieve closed-loop regulation; the wireless charger 14 is used to wirelessly charge the in-vivo controller 13 to ensure that the in-vivo controller 13 can work independently and normally; the mobile terminal 15 can be a mobile phone, a computer, or other controllable devices, etc. If it is a mobile phone or a computer, it can receive the signals sent by the in-vivo controller 13 and decode them to achieve real-time monitoring of electroencephalogram signals. At the same time, through analysis, the stimulation parameters are optimized and adjusted and sent to the in-vivo controller 13 to adjust the built-in stimulation strategy. If it is a controllable device, it can receive the signals sent by the in-vivo controller 13 and decode them to generate control instructions, thereby controlling the operation of the device.

[0006] Compared with traditional stents, the stent electrode of the present invention has an additional long wire, so traditional implant devices are not very applicable. The present invention specially designs two specific implant devices for the implantation of the stent electrode of the present invention.

[0007] Implant device 1: As Figure 3 shown, it includes a sheath 31 and a guide wire 33; the stent electrode 32 to be implanted is placed inside the sheath 31. The sheath 31 ensures that the self-expanding stent framework is always in a compressed state inside the sheath. The internal structure of the sheath is as Figure 4As shown in the figure, it includes the head end stop 41 of the guide wire 33, the notch 42, and the tail end 43 of the guide wire 33. The head end stop 41 is used to limit the position of the stent framework. Adjusting the tail end 43 of the guide wire can control the forward or backward movement of the stent framework; the notch 42 ensures that the adjustment process will not be affected by the interaction between the stop and the wire, thus ensuring the smoothness of the adjustment. During the implantation process of the stent electrode, the sheath 31, the stent electrode 32, and the guide wire 33 are advanced simultaneously to reach the target area. Then, the guide wire is fixed and the sheath is withdrawn backward to expose the stent electrode in the blood vessel. After it is fully self-expanded, the guide wire is withdrawn to complete the implantation of the stent electrode.

[0008] Implantation device 2: As Figure 5 shown in the figure, it includes a sheath 51 and a guide wire 53; the stent electrode 52 to be implanted is placed inside the sheath 51. The internal structure of the sheath is as Figure 6 shown in the figure, which includes the head end 61 of the guide wire and the tail end 62 of the guide wire. The guide wire 53 is a hollow tubular structure. The head end 61 of the guide wire is enlarged to match the structure at the end of the stent, so as to provide a thrust to the stent framework. The wire is accommodated inside the tail end 62 of the guide wire. During the implantation process, the sheath 51, the stent electrode 52, and the guide wire 53 are also advanced synchronously to the target area. Then, the guide wire is fixed and the sheath is withdrawn backward. After the stent is fully self-expanded, the guide wire is withdrawn backward so that the head end 61 of the guide wire is separated from the end of the stent until it is completely withdrawn, completing the implantation of the stent electrode.

[0009] The implantation of the stent electrode is realized through a specifically designed implantation device.

[0010] The interventional brain-computer interface system based on the stent electrode designed in the present invention implants the stent electrode into the blood vessel near the target brain area through vascular intervention as an interaction interface between the brain and the in-vivo controller; the in-vivo controller is implanted subcutaneously in the chest, which can analyze the electroencephalogram signals collected through the stent electrode, or issue a discharge command to stimulate the brain area through the stent electrode; it can perform energy exchange with an external charger; it can also perform information exchange with an external mobile terminal. In addition, the present invention also designs an implantation system for the stent electrode to send it to the target area.

[0011] The present invention adopts an interventional means, which can achieve minimally invasive, improve the signal quality, provide a therapeutic effect, and at the same time realize closed-loop regulation of the target brain area through signal acquisition and analysis and nerve stimulation, so as to effectively treat related brain diseases.

[0012] The positive technical effects of the present invention are mainly reflected in:

[0013] (1) Achieving minimally invasive and high-resolution electroencephalogram signal acquisition;

[0014] (2) Closed-loop regulation for treating brain diseases;

[0015] (3) It can directly control external devices through electroencephalogram signals without limb operation;

[0016] (4) The stent electrode combines the functions of a traditional vascular stent and can comprehensively treat various diseases. Description of the Drawings

[0017] Figure 1 This is a schematic structural diagram of the implantable brain-computer interface system based on the stent electrode of the present invention.

[0018] Figure 2 This is a partially enlarged schematic diagram of the stent electrode in the present invention.

[0019] Figure 3 This is a structural diagram of the stent electrode implantation device 1 in the present invention.

[0020] Figure 4 This is a schematic internal structure diagram of the stent electrode implantation device 1 in the present invention.

[0021] Figure 5 This is a structural diagram of the stent electrode implantation device 2 in the present invention.

[0022] Figure 6 This is a schematic internal structure diagram of the stent electrode implantation device 2 in the present invention.

[0023] Reference numerals in the figures: 11 is the stent electrode, 12 is the wire bundle, 13 is the in-vivo controller, 14 is the external wireless charger, 15 is the mobile terminal; 21 is the stent skeleton, 22 is the electrode 22, 23 is the wire. 31 is the sheath, 32 is the stent electrode, 33 is the guide wire; 41 is the guide wire head end stopper, 42 is the notch, 43 is the guide wire tail end. 51 is the sheath, 52 is the stent electrode, 53 is the guide wire; 61 is the guide wire head end, 62 is the guide wire tail end. Detailed Embodiments

[0024] In the present invention, the stent skeleton 21 can be made of materials such as nitinol, medical stainless steel 316L, etc. The support structure can be V-shaped, sinusoidal, etc., the connecting rib can be I-shaped, etc. The width and thickness of the skeleton do not exceed 0.2 mm and are processed by weaving or etching, and the surface has an insulating coating such as parylene. In the expanded state, the outer diameter of the stent can be 1-4 mm, and the length can be 5-20 mm, which is specifically selected according to the inner diameter and shape of the blood vessel at the implantation position. The electrode 22 can be a platinum sheet, with a diameter of 0.05-0.2 mm and a thickness of 0.01-0.05 mm, and is bonded to the outer side surface of the stent skeleton 21 by a bioadhesive. The number of electrodes can be 2-12. The wire 23 can be a platinum wire or a platinum-iridium alloy wire, with a diameter of 0.01-0.025 mm, and is also bonded to the outer side surface of the stent skeleton 21, and the outer surface of the wire also has an insulating coating. In addition, the wire 23 can also be a flexible FPC manufactured by micro-nano technology.

[0025] In the implant device, the materials of the sheath tube and the guide wire are similar to those of traditional vascular intervention devices. The sheath tube material can be polytetrafluoroethylene (PTFE), polyurethane (PU), polyamide (Nylon), etc., and the guide wire material can be nitinol, platinum, etc. The diameters of the sheath tube and the guide wire depend on the size of the stent electrode used specifically.

[0026] References

[0027] [1] Sahat N. Wheelchair controlled by human brainwave using brain-computer interface system for paralyzed patient[D]. Malaysia: Universiti Tun Hussein Onn, 2020.

[0028] [2] Flesher S N, Downey J E, Weiss J M, et al. A brain-computer interface that evokes tactile sensations improves robotic arm control[J]. Science, 2021, 372(6544): 831-836.

[0029] [3] Vansteensel M J, Pels E G M, Bleichner M G, et al. Fully implanted brain-computer interface in a locked-in patient with ALS[J]. New England Journal of Medicine, 2016, 375(21): 2060-2066.

[0030] [4] Chavarriaga R, Carey C, Contreras-vidal J L, et al. Standardization of neurotechnology for brain-machine interfacing: state of the art and recommendations[J]. IEEE Open Journal of Engineering in Medicine and Biology, 2021, 2: 71-73.

[0031] [5]Marshall D, Coyle D, Wilson S, et al. Games, gameplay, and BCI: The state of the art[J]. IEEE Transactions on Computational Intelligence and AI in Games, 2013, 5(2):82-99。

Claims

1. An interventional brain-computer interface system based on a bracket electrode, characterized in that: The invention comprises a support electrode (11), a wire harness (12), an in-vivo controller (13), and an out-vivo wireless charger (14) and a mobile terminal (15); wherein: The support electrode (11) comprises a support frame (21), an electrode (22) and a wire (23). The electrode (22) is fixed on the support frame (21) and insulated from the support frame. The wire (23) runs along the veins of the frame and converges into a bundle at the tail end, namely the wire bundle (12). The support electrode (11) is implanted into a blood vessel near a target area of ​​the brain through the internal jugular vein through an interventional procedure. The support frame (21) is used to open the blood vessel to ensure that the electrode (22) is in close contact with the inner wall of the blood vessel and maintains a relatively close distance with the brain area outside the blood vessel, thereby improving the signal quality. The electrode (22) is used to collect brain electrical signals and is also used as a stimulation electrode to electrically stimulate the nearby brain area. The wire bundle (12) passes through the blood vessel from the neck opening and is connected to an in-vivo controller (13) buried under the skin of the chest. The in-vivo controller (13) collects brain electrical signals through the electrode (22). The device generates an electrical signal and analyzes it. On the one hand, the encoded signal is sent to an external mobile terminal (15) through wireless transmission. On the other hand, a stimulation strategy is generated to electrically stimulate the brain area through the electrode (22) to treat the disease, thereby realizing closed-loop control. The wireless charger (14) is used to wirelessly charge the internal controller (13) to ensure that the internal controller (13) can work normally and independently. The mobile terminal (15) is a mobile phone, a computer or other controllable device. If it is a mobile phone or a computer, the signal sent by the internal controller (13) is received and decoded to realize real-time monitoring of the brain electrical signal. At the same time, after analysis, the stimulation parameters are optimized and adjusted, and sent to the internal controller (13) to adjust the built-in stimulation strategy. If it is a controllable device, the signal sent by the internal controller (13) is received and decoded to generate a control instruction, thereby controlling the operation of the device.

2. A device for implanting a stent electrode in an interventional brain-computer interface system as claimed in claim 1, characterized in that: There are two types: An implantation device 1 comprises a sheath tube (31) and a guide wire (33), wherein a stent electrode (32) to be implanted is placed in the sheath tube (31); the sheath tube (31) is used to ensure that the self-expanding stent skeleton is always in a compressed state in the sheath tube; the internal structure of the sheath tube comprises a guide wire head end block (41), a notch (42), and a guide wire tail end (43); the head end block (41) is used to limit the position of the stent skeleton, and the stent skeleton can be controlled to move forward or backward by adjusting the guide wire tail end (43); the notch (42) ensures that the smooth adjustment is not affected by the interaction between the block and the guide wire during the adjustment process; during the implantation of the stent electrode, the sheath tube (31), the stent electrode (32), and the guide wire (33) are simultaneously advanced to reach the target area, and then the guide wire is fixed and the sheath tube is withdrawn backward to expose the stent electrode in the blood vessel, and the guide wire is withdrawn after the stent electrode is completely self-expanded, thereby completing the implantation of the stent electrode; The implantation device 2 comprises a sheath tube (51) and a guide wire (53), wherein the stent electrode (52) to be implanted is placed in the sheath tube (51); the internal structure of the sheath tube comprises a guide wire head end (61) and a guide wire tail end (62); the guide wire (53) is a hollow tubular structure, the guide wire head end (61) is enlarged to match the end structure of the stent frame, thereby providing a thrust to the stent frame, and the guide wire tail end (62) accommodates the wire inside; During the implantation process, the sheath (51), the stent electrode (52), and the guide wire (53) are simultaneously advanced to the target area, and then the guide wire is fixed and the sheath is withdrawn backwards. After the stent is fully self-expanded, the guide wire is withdrawn backwards so that the guide wire head (61) is separated from the stent end and completely withdrawn, completing the implantation of the stent electrode.

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