A system for introducing a flexible deep brain neural electrode

Abstract

The present application relates to a system for introducing a flexible deep brain electrode, which is divided into three parts of an outer sheath, a pusher and an electrode. The distal end of the flexible array electrode is provided with a degradable curved anchor. After the introduction system is implanted in a specific position, the inner pusher is pushed to move the flexible array electrode in the outer sheath, and after the curved anchor of the flexible array electrode is fixed, the inner pusher and the outer sheath are withdrawn in turn. The introduction system can quickly send the flexible polymer probe into the brain. By delivering the degradable curved anchor, the influence of the micro-movement of the flexible electrode after implantation due to human respiration and movement can be effectively reduced, and the working time of the electrode can be effectively prolonged. At the same time, with the extension of the implantation time, the curved anchor will slowly degrade, minimizing the damage to the brain tissue when the electrode is removed.

Description

Technical Field

[0001] This invention belongs to the field of implantable medical devices, and in particular a system for introducing flexible deep brain neural electrodes. Background Technology

[0002] Brain-computer interfaces (BCIs) establish a novel communication and control channel between the brain and the external environment, independent of peripheral nerves and muscles, enabling direct interaction between the brain and external devices. This technology allows communication between the human (or other animal) brain and the external environment to control devices, thus playing a role in monitoring, replacement, improvement / recovery, enhancement, and supplementation. Currently, there are two main types: non-invasive and invasive. Non-invasive methods can record millions of neurons passing through the skull, but this signal is distorted and non-specific. Invasive methods are further divided into surface-level and deep-brain electrodes, depending on the implantation site. Surface-level invasive electrodes can record clearer signals than non-invasive electrodes, but they can only record the activity of surface neurons and cannot record signals from deep within the brain, greatly limiting their use. Deep-brain electrodes are mostly made of hard metals or semiconductors.

[0003] While rigid metal array electrodes facilitate brain penetration, size, Young's modulus, and bending stiffness mismatches between rigid probes and brain tissue can lead to immune responses, limiting the functionality and lifespan of these devices. Another approach is to use thin, flexible, multi-electrode polymer probes. The small size and increased flexibility of these probes should provide greater biocompatibility. However, a drawback of this approach is that thin polymer probes are not rigid enough to be directly inserted into the brain; their insertion must be facilitated by reinforcing ribs, injection, or other methods, all of which are slow. To meet the functional requirements of high-bandwidth brain-computer interfaces while leveraging the properties of thin-film devices, it is crucial to develop a method for efficiently and independently inserting a large number of fine, flexible polymer probes into multiple brain regions. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a system for introducing flexible deep brain neural electrodes, which can quickly deliver flexible polymer probes into the brain.

[0005] The technical solution for achieving the objective of this invention is as follows:

[0006] A system for introducing flexible deep brain neural electrodes, comprising:

[0007] An electrode has a first end and a second end, the first end being connected to an electrical stimulation generator unit;

[0008] An outer sheath having a cavity having a first opening and a second opening, wherein the electrode enters the cavity through the first opening and exits the cavity through the second opening;

[0009] An anchoring element is an elastic body having a fixed end and a movable end. The fixed end is fixedly connected to the second end of the electrode. The movable end moves with the electrode and has two states: the first state is moving within the cavity, and the second state is anchored to the brain tissue outside the cavity.

[0010] A pusher, which is movable, pushes the electrode through the anchor to pass through the cavity from the second opening.

[0011] Furthermore, the cavity has a first wall surface, and the first wall surface has a guide groove. The guide groove has a distal end and a proximal end. The distal end is formed in the second opening of the cavity, and the proximal end is formed in the first opening of the cavity. The movable end of the anchoring member moves within the guide groove, and the guide groove restricts the trajectory of the pushing member pushing the electrode.

[0012] Furthermore, the pusher is positioned between the first wall of the cavity and the electrode.

[0013] Furthermore, the pusher terminal has an interface that interfaces with the anchor.

[0014] Furthermore, the second opening of the outer sheath has a first slit and a second slit, and the angle between the first slit and the second slit is 45 to 60 degrees.

[0015] The implantation location is calculated based on the length of the pusher and a brain CT scan to allow the pusher flexible array electrodes to move freely between the protected and test locations.

[0016] In the protective position, the electrode is housed between the pusher and the first wall of the outer sheath. In the test position, the anchor extends fully and anchors to the brain tissue. Then, the pusher and the outer sheath are disengaged in sequence to release the electrode.

[0017] Furthermore, the outer sheath has a cavity width of 0.8-1.2 mm, a height of 0.2-0.5 mm, and a length of 100-150 mm.

[0018] Furthermore, the pusher is a solid needle with a diameter of 0.1-0.5 mm.

[0019] Furthermore, the material of the pusher is one or more of polymers, precious metals, stainless steel, and titanium alloys.

[0020] Furthermore, the distal end of the guide groove has a protrusion to prevent accidental dislodgement of the pusher and electrode.

[0021] Furthermore, the electrode is a flexible multi-channel array electrode, having a thickness, when combined with the pusher, between the inner diameter of the outer sheath and the thickness, with an optimal thickness of less than 100 μm; the electrode contact area is 100-1000 μm². 2 Each electrode channel in the array has a width of 1-50 μm and the number of electrode channels ranges from 2 to 100.

[0022] Furthermore, the electrode has an elastic modulus close to that of brain tissue.

[0023] Furthermore, the electrode substrate material includes flexible insulating materials such as poly(p-toluene), polyimide, and polydimethylsiloxane.

[0024] Furthermore, the anchoring element is made of polyglycolic acid, polylactic acid, polylactic acid-glycolic acid copolymer, polycaprolactone, polyurethane, or polyethylene glycol.

[0025] Advantages and beneficial effects of the present invention:

[0026] This invention relates to a system for introducing flexible deep brain electrical electrodes, which can rapidly deliver flexible polymer probes into the brain. By delivering a biodegradable, flexible anchor, the system effectively reduces the impact of micro-movements of the electrodes caused by human respiration and movement after implantation, thus effectively extending the electrode's working time. Furthermore, the flexible anchor slowly degrades over time, minimizing damage to brain tissue during electrode removal. Attached Figure Description

[0027] Figure 1 It is a schematic diagram of the system introduced based on the description;

[0028] Figure 2 It is a partial cross-sectional view based on the introduction system during the described electrode pushing process;

[0029] Figure 3 It is based on the schematic diagram of the movement of the pushing component and the anchoring component during the electrode pushing process described;

[0030] Figure 4 It is based on the cross-sectional schematic diagram of the described outer sheath.

[0031] Numbering on the map:

[0032] 100 is the electrode introduction system, 110) is the outer sheath, 120) is the pusher, 130) is the electrode, 1101) is the second opening, 1102) is the first cut surface, 1103) is the second cut surface, 1104) is the included angle, 1105) is the first wall surface, 1106) is the guide groove, 131) is the anchor, 1311) is the movable end, 1312) is the fixed end, 1301) is the second end, and 1201) is the interface. Detailed Implementation

[0033] Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. It should be understood that other embodiments may also be employed, and structural and functional changes may be made without departing from the corresponding scope of the invention. Furthermore, features of the various embodiments may be combined or modified without departing from the scope of the invention. Thus, the following description is given by way of illustration only and should not in any way limit the various alternatives and modifications that may be made with respect to the illustrated embodiments and that remain within the spirit and scope of the invention. For ease of understanding, the term "proximal" in this patent generally refers to the end of the electrode that is not inserted into the body, and "distal" generally refers to the end of the electrode inserted into the body near a nerve. As a non-limiting example, the device may allow the placement of electrodes to deliver stimulation to nerves innervating a region, such as the subthalamic nucleus, globus pallidus nucleus, etc.

[0034] The device allows target neurons to be identified before electrode placement and deployment, as part of a non-surgical procedure. There is a clinical need for a device that can directly measure pathological brain activity and provide adjustable stimulation to treat neurological and psychiatric disorders associated with abnormal brain circuitry. Electrodes are implanted at specific locations within the brain and supplied with a constant or intermittent current from an implanted battery power source. This dual nature as both a probe and modulator in the brain's circuitry enables the device to treat disorders affecting motor, limbic, memory, and cognitive functions.

[0035] Examples of this system include an introduction and testing system that, after implantation, is secured with anchors to reduce the impact of brain micromovements caused by respiration or movement on the electrodes. Specifically, when brain electrodes are implanted in the brain, micromovements caused by respiration or movement lead to an immune response that slowly creates a tissue capsule primarily composed of glial cells. As the implantation time increases and the capsule thickens, neurons around the electrodes gradually disappear or die, resulting in decreased or even lost electrode function. The invention described herein eliminates these problems while still allowing the deployment of anti-migration flexible array electrodes with distal anchors.

[0036] like Figure 1An embodiment of the electrode introduction system 100 is shown, with particular emphasis on how the electrodes are deployed. The electrode introduction system 100 includes a pusher 120, an electrode 130, and an outer sheath 110. In this embodiment, the outer sheath 110 has a diameter of 0.3 × 1 mm. 2 The area and 0.37×1.17mm 2 The outer diameter of the outer sheath 110. The outer sheath 110 has a cavity with a first opening and a second opening 1101. The electrode 130 enters the cavity through the first opening and exits the cavity through the second opening 1101. The second opening 1101 of the outer sheath 110 has a first cross-section 1102 and a second cross-section 1103. The angle 1104 between the first cross-section 1102 and the second cross-section 1103 is 45 to 60 degrees. The cavity has a first wall surface 1105, and a guide groove 1106 is formed on the first wall surface 1105. The guide groove 1106 has a distal end and a proximal end. The distal end is formed in the second opening 1101 of the cavity, and the proximal end is formed in the first opening of the cavity.

[0037] The pusher 120 is disposed within the outer sheath 110 to allow it to extend out of the cavity. The electrode 130 is movable freely with the pusher 120 relative to the inner surface of the outer sheath 110.

[0038] like Figure 1 and 2 As shown, the anchoring member 131 is an elastic body with a fixed end 1312 and a movable end 1311. The fixed end 1312 is fixedly connected to the second end 1301 of the electrode 130. The movable end 1311 moves with the electrode 130. The anchoring member 131 has two states: the first state is that it moves within the guide groove 1106 of the cavity, and the guide groove 1106 restricts the trajectory of the pusher 120 pushing the electrode 130; the second state is that it is anchored to the brain tissue outside the cavity. The pusher 120 has a diameter of 0.2 mm and is needle-shaped. The end of the pusher 120 has an interface 1201, which can be connected to the anchoring member 131, such as... Figure 3 As shown.

[0039] Figure 2 The relative movement of the pusher 120 and the outer sheath 110 is illustrated. Upon insertion, these elements move in a coordinated manner. To deploy the electrode 130, the pusher 120 is pushed, causing the electrode 130 to extend beyond the outer sheath 110. Once the pusher 120 extends sufficiently beyond the cavity 110, the anchor 131 is released from the outer sheath 110 and embeds itself into the tissue of the adjacent electrode introduction system 100. The pusher 120 and the outer sheath 110 are then withdrawn in sequence, thereby releasing the electrode 130. This allows the anchor 131 to be released and extend through a channel in the sheath.

[0040] The electrode contacts in this patent application are characterized by being designed as surface-treated electrode sites. For example, the mechanical and / or electrical properties of the electrode sites, such as impedance, site material, specific surface area, and hydrophilicity, can be improved by selecting different processing methods.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

[0042] Matters not covered in this invention are not publicly known technologies.

Claims

1. A system for introducing flexible deep brain neural electrodes, characterized in that, include: The electrode (130) has a first end and a second end (1301), the first end being connected to the electrical stimulation generator unit; The outer sheath (110) has a cavity with a first opening and a second opening (1101), and the electrode (130) enters the cavity through the first opening and exits the cavity through the second opening (1101). An anchor (131) is an elastic body having a fixed end (1312) and a movable end (1311). The fixed end (1312) is fixedly connected to the second end (1301) of the electrode (130). The movable end (1311) moves with the electrode (130). The anchor (131) has two states: the first state is moving within the cavity, and the second state is anchored to the brain tissue outside the cavity. A pusher (120) is movable and pushes the electrode (130) through the anchor (131) so that it passes through the cavity from the second opening (1101); The cavity has a first wall surface (1105) and a guide groove (1106) formed therein. The guide groove (1106) has a distal end and a proximal end. The distal end is formed in the second opening (1101) of the cavity, and the proximal end is formed in the first opening of the cavity. The movable end (1311) of the anchor (131) moves within the guide groove (1106).

2. The system according to claim 1, characterized in that, The pusher (120) is placed between the first wall surface (1105) of the cavity and the electrode (130).

3. The system according to claim 2, characterized in that, The pusher (120) has an interface (1201) that is connected to the anchor (131).

4. The system according to claim 3, characterized in that, The second opening (1101) of the outer sheath (110) has a first cut surface (1102) and a second cut surface (1103), and the included angle (1104) between the first cut surface (1102) and the second cut surface (1103) is 45 to 60 degrees.

5. The system according to claim 4, characterized in that, The guide groove (1106) has a protrusion (112) at its distal end.

6. The system according to claim 5, characterized in that, The electrode (130) is a flexible multi-channel array electrode.

7. The system according to claim 6, characterized in that, The material of the pusher (120) is one or more of polymer, precious metal, stainless steel, and titanium alloy.

8. The system according to claim 7, characterized in that, The electrode (130) substrate material is a flexible insulating material.

9. The system according to claim 8, characterized in that, The anchor (131) is made of polyhydroxyacetic acid, polylactic acid, polylactic acid-hydroxyacetic acid copolymer, polycaprolactone, polyurethane or polyethylene glycol.

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