Needle-punched stent electrode for interventional brain-computer interface and implantation method of needle-punched stent electrode

Abstract

The invention belongs to the technical field of brain-computer interfaces, and particularly relates to a needling type stent electrode for an interventional brain-computer interface and an implantation method of the needling type stent electrode. The needling type stent electrode comprises a stent framework, a wire net and a needling type electrode, the stent skeleton is of a cylindrical hollow net-shaped structure and is used for expanding and supporting blood vessels, and meanwhile it is guaranteed that the electrode is tightly attached to the blood vessel wall and keeps a close enough distance from a target brain area so as to guarantee signal quality. The wire net is of a network structure matched with the stent framework and is tightly attached to and circulates the inner side face of the stent framework, and signal transmission between the electrodes and a far-end controller is achieved. A plurality of needle-punched electrodes are respectively arranged in the wire net; the acupuncture type electrode gets close to a target brain area by puncturing a blood vessel wall and is used for collecting electroencephalogram signals, or the electrode releases electric pulses to stimulate the brain area so as to treat related diseases. Implantation is carried out through mutual cooperation of a sheathing canal and a balloon. According to the invention, the quality of acquired signals is improved, and minimally invasive acquisition and high resolution of electroencephalogram signals are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of brain-computer interface, and in particular relates to a bracket electrode and an implantation method thereof. Background Art

[0002] Brain-computer interface is a technology that establishes communication and control channels between the brain and external devices, uses the brain's bioelectric signals to directly control external devices, or uses external stimulation to regulate brain activity, thereby enhancing, improving and extending brain functions. There are three main ways to implement brain-computer interfaces: invasive, non-invasive, and interventional. Among them, invasive brain-computer interfaces are the mainstream of current research and have been widely used. By collecting brain signals related to limbs and obtaining movement intentions, the purpose of controlling prosthetic limbs or machine-assisted devices can be achieved, such as brain-computer controlled wheelchairs. [1] , Paralyzed patients control robotic arms to complete object lifting tasks [2] , drive the cursor to simulate keyboard input [3] There are also researchers who use neural stimulation to achieve the purpose of neural regulation. For example, Professor Li Luming's team at Tsinghua University has developed an implantable neural stimulator that can be used to treat Parkinson's disease patients based on deep brain stimulation (DBS). It achieves neural regulation of patients through the local electric field 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 can easily cause rejection reactions in the human body; and the electrodes need to be in direct contact with brain tissue, and the electrode development technology is difficult and has high technical barriers. Non-invasive brain-computer interfaces usually only require wearing electroencephalogram (EEG) signal acquisition equipment on the scalp, which is less harmful to the human body and has lower technical difficulty. 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 methods is that they are too far away from the cerebral cortex, making it difficult to achieve continuous, stable and accurate capture of EEG signals.

[0003] Interventional brain-computer interface uses minimally invasive methods to make a small puncture in the blood vessels and achieve brain-computer connection through minimally invasive surgery similar to cerebral vascular stents. It causes less harm to the human body than invasive methods, has higher signal acquisition quality than non-invasive methods, and can reach deep brain areas through the vascular 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 acupuncture-type stent electrode for an invasive brain-computer interface with high signal quality and good integration with blood vessels, and a method for implanting the same, so as to avoid the disadvantages of invasive brain-computer interfaces requiring craniotomy to implant electrodes, which causes greater trauma, and the problem of low signal quality in non-invasive brain-computer interfaces.

[0005] The acupuncture type bracket electrode for interventional brain-computer interface provided by the present invention specifically comprises a bracket frame 11, a wire mesh 22, and an acupuncture type electrode 21; wherein the bracket frame 11 structure is shown in Figure 1 As shown, it is a cylindrical hollow mesh structure; the stent skeleton 11 is used to expand and support the blood vessels, while ensuring that the electrodes are closely attached to the blood vessel wall and keep a sufficiently close distance to the target brain area to ensure signal quality; the structure of the wire mesh 22 is shown in Figure 2 As shown, it is a network structure matching with the stent frame 11, which is closely attached to and runs along the inner side of the stent frame 11 to realize signal transmission between the electrode and the remote controller; the wire network 22 is gathered into a bundle at the end to minimize the impact on the blood flow; there are multiple acupuncture electrodes 21, which are respectively arranged on a certain wire in the wire network 22; the acupuncture electrodes 21 approach the target brain area by puncturing the blood vessel wall, and are used to collect brain electrical signals, or release electrical pulses through the electrodes to stimulate the brain area to treat related diseases;

[0006] The acupuncture electrode 21 includes a conical electrode 31 and an electrode holder 32 fixed at the bottom of the conical electrode 31;

[0007] The acupuncture electrode 21 is located at the connecting ribs of the stent frame; a circular hole is provided at the connecting ribs of the stent frame, the diameter of which matches the acupuncture electrode 21, for the acupuncture electrode 21 to pass through, penetrate the blood vessel wall to approach the brain neurons, and the electrode base is embedded in the stent frame.

[0008] The acupuncture stent electrode of the interventional brain-computer interface designed by the present invention is implanted by using a sheath and a balloon, which cooperate with each other: the initial state of the acupuncture stent electrode is a contracted state; the acupuncture stent electrode is implanted into the blood vessel from the inside of the sheath along with the sheath, and the sheath is used to ensure the smooth implantation process of the stent electrode without friction with the blood vessel wall; the stent electrode is attached to the outside of the balloon, and the balloon pushes and expands the stent electrode in the sheath. During the implantation process, the sheath, stent electrode, and balloon are simultaneously advanced to the target area, and then the balloon is fixed and the sheath is withdrawn backward to expose the stent electrode to the blood vessel; the catheter part is inflated to the balloon part to open the stent, and at the same time, the electrode needle part is pushed to pierce the blood vessel wall. After the stent is fully opened, the balloon is reduced and withdrawn to complete the implantation of the stent electrode.

[0009] Compared with the sheet electrodes attached to the outer side of the stent frame, the acupuncture-type stent electrodes designed by the present invention for interventional brain-computer interface can penetrate the blood vessel wall to further reduce the distance from the brain tissue, improve the quality of blood flow signals, and also strengthen the combination of the stent electrodes and blood vessels to prevent them from shifting. The present invention can achieve minimally invasive and high-resolution EEG signal acquisition; the stent electrodes have the functions of traditional vascular stents and can be used for comprehensive treatment of various diseases. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the overall structure of the acupuncture-type stent electrode of the present invention.

[0011] Figure 2 Schematic diagram of the electrode and wire network after removing the stent skeleton.

[0012] Figure 3 This is a partial enlarged schematic diagram of the acupuncture electrode.

[0013] Figure 4 Schematic diagram of the outer side of the electrode and bracket frame assembly.

[0014] Figure 5 Schematic diagram of the inner side of the electrode and stent frame assembly.

[0015] Figure 6 Schematic diagram of the overall structure of the implant device.

[0016] Figure 7 Schematic diagram of the assembly relationship between the stent electrode and the balloon.

[0017] Numbers in the figure: 11 is the stent skeleton, 12 is the wire, 21 is the acupuncture electrode, 22 is the wire mesh, 31 is the conical electrode, 32 is the electrode base; 33 is the wire; 41 is the connecting rib, 42 is the conical electrode; 51 is the electrode base, 52 is the wire, 61 is the sheath, 62 is the stent electrode, 63 is the balloon, 64 is the circular hole; 71 is the stent electrode, 72 is the capsule part, and 73 is the catheter part. DETAILED DESCRIPTION

[0018] Figure 1 The stent electrode is schematically shown as a whole. The stent skeleton 11 can be made of nickel-titanium alloy, medical stainless steel 316L and other materials, the support structure can be V-shaped, sinusoidal, etc., the connecting ribs can be I-shaped, etc., the skeleton width and thickness are not more than 0.2mm, and it is 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 1-4mm, and the length can be 5-20mm, which is selected according to the inner diameter and shape of the blood vessel at the implantation location.

[0019] Figure 2 As shown, the electrode 21 has 6 channels and is symmetrically distributed. The actual number of electrode channels can be 2-12, and the distribution method can be determined according to specific needs. The wire mesh 22 runs along the inner side of the stent frame and converges into a bundle at the end. The wire can be a platinum wire or a platinum-iridium alloy wire with a diameter of 0.01-0.025mm, and the surface is also coated with an insulation coating. In addition, the wire can also be a flexible FPC manufactured by micro-nano technology.

[0020] Figure 3The figure shows a partial enlarged schematic diagram of the electrode, including an electrode needle 31, an electrode base 32, and a wire 33. The electrode material can be pure platinum. The base is cylindrical, with a diameter of 0.05-0.15mm and a thickness of 0.05-0.1mm; the needle is conical, with a bottom diameter of 0.05-0.15mm and a height of 0.25-0.5mm.

[0021] Figure 4 , Figure 5 Schematic diagram of the assembly of electrodes and the support frame. Figure 4 The schematic diagram of the outer side of the stent frame shows that the electrode is located at the stent frame connecting ribs. The electrode needle 42 passes through the small hole on the frame and can penetrate the blood vessel wall to approach the brain neurons. The small hole is cylindrical and has a diameter equal to the bottom diameter of the electrode needle. Figure 5 The schematic diagram of the inner side of the stent frame is shown in FIG. The electrode base 51 is embedded in the stent frame with an embedding depth of 0.05-0.1 mm. The wire 52 runs along the inner side of the stent frame to form a wire network and is gathered into a bundle at the rear end of the stent frame.

[0022] Figure 6 It is a schematic diagram of an implantation device, including a sheath 61 , a stent electrode 62 , and a balloon 63 . Figure 7 The figure shows the assembly relationship between the stent electrode and the balloon, including the stent electrode 71, the balloon body 72, and the catheter body 73. The sheath is used to ensure the smooth implantation of the stent electrode without friction with the blood vessel wall. The balloon is used to push and expand the stent electrode. The stent electrode is initially in a contracted state and attached to the surface of the balloon body. During the implantation process, the sheath, stent electrode, and balloon are simultaneously pushed to the target area, and then the balloon is fixed and the sheath is withdrawn backwards to expose the stent electrode to the blood vessel. The balloon body is inflated through the catheter part to expand the stent skeleton, and at the same time, the electrode needle is pushed to pierce the blood vessel wall. After the stent is fully expanded, the balloon is shrunk and withdrawn to complete the implantation of the stent electrode.

[0023] References

[0024] [1]Sahat N.Wheelchair controlled by human brainwave using brain-computer interface system for paralyzed patient[D].Malaysia:Universiti TunHussein Onn,2020.

[0025] [2]Flesher S N,Downey J E,Weiss J M,et al.Abrain-computer interfacethat evokes tactile sensations improves robotic arm control[J].Science,2021,372(6544):831-836.

[0026] [3]Vansteensel M J,Pels E G M,Bleichner M G,et al.Fully implantedbrain-computer interface in a locked-in patient with ALS[J].New EnglandJournal of Medicine,2016,375(21):2060-2066.

[0027] [4]Chavarriaga R,Carey C,Contreras-vidal J L,et al.Standardization ofneurotechnology forbrain-machine interfacing:state of the art andrecommendations[J].IEEE Open Journal ofEngineering in Medicine and Biology,2021,2:71-73.

[0028] [5]Marshall D,Coyle D,Wilson S,et al.Games,gameplay,and BCI:The stateof the art[J].IEEETransactions on Computational Intelligence and AI in Games,2013,5(2):82-99。

Claims

1. An acupuncture-type stent electrode for an interventional brain-computer interface, characterized in that: The specific structure includes a support frame (11), a wire mesh (22), and an acupuncture electrode (21); wherein the support frame (11) is a cylindrical hollow mesh structure; the support frame (11) is used to expand and support the blood vessel, while ensuring that the electrode is closely attached to the blood vessel wall and maintains a sufficiently close distance to the target brain area to ensure signal quality; the wire mesh (22) is a network structure matching the support frame (11), which is closely attached to and runs along the inner side of the support frame (11) to achieve signal transmission between the electrode and the remote controller; the wire mesh (22) converges into a bundle at the end; there are multiple acupuncture electrodes (21), which are respectively arranged on a certain wire in the wire mesh (22); the acupuncture electrode (21) approaches the target brain area by puncturing the blood vessel wall, and is used to collect brain electrical signals, or release electrical pulses through the electrode to stimulate the brain area to treat related diseases; The acupuncture electrode (21) comprises a conical electrode (31) and an electrode holder (32) fixed to the bottom of the conical electrode; The acupuncture electrode (21) is located at the connecting rib portion of the stent frame (11); a circular small hole is provided at the connecting rib portion of the stent frame (11), the diameter of the small hole matches the acupuncture electrode (21), and is used for the acupuncture electrode to pass through and penetrate the blood vessel wall to approach brain neurons, and the electrode base (32) is embedded in the stent frame.

2. The acupuncture-type bracket electrode for interventional brain-computer interface according to claim 1, characterized in that: The stent skeleton (11) has a width and thickness of no more than 0.2 mm, is processed by weaving or etching, and has an insulating coating on the surface; in the expanded state, the stent skeleton has an outer diameter of 1-4 mm and a length of 5-20 mm.

3. The acupuncture-type stent electrode for interventional brain-computer interface according to claim 1, characterized in that: In the wire mesh (22), the number of electrode channels is 2-12; the electrode wires in the wire mesh are platinum wires or platinum-iridium alloy wires with a diameter of 0.01-0.025 mm and an insulating coating on the surface.

4. The acupuncture-type bracket electrode for interventional brain-computer interface according to claim 1, characterized in that: In the needle-piercing electrode (21), the electrode material is pure platinum, the base is cylindrical, with a diameter of 0.05-0.15 mm and a thickness of 0.05-0.1 mm; the conical electrode part has a bottom diameter of 0.05-0.15 mm and a height of 0.25-0.5 mm.

5. The method for implanting an acupuncture-type stent electrode for an interventional brain-computer interface as claimed in any one of claims 1 to 4, characterized in that: A sheath and a balloon are used to cooperate with each other: the initial state of the acupuncture stent electrode is a contracted state; the acupuncture stent electrode is implanted into the blood vessel from the inside of the sheath tube, and the sheath tube is used to ensure the smooth implantation process of the stent electrode without friction with the blood vessel wall; The stent electrode is attached to the outside of the balloon, which pushes and expands the stent electrode in the sheath. During the implantation process, the sheath, stent electrode and balloon are simultaneously advanced to the target area, and then the balloon is fixed and the sheath is withdrawn backward to expose the stent electrode to the blood vessel. The balloon body is inflated through the catheter to expand the stent, and at the same time, the electrode needle is pushed to pierce the blood vessel wall. After the stent is fully expanded, the balloon is deflated and withdrawn to complete the stent electrode implantation.

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