Electroencephalogram-ultrasonic composite ECoG electrode

Abstract

The invention provides an electroencephalogram-ultrasonic composite ECoG electrode, the electroencephalogram-ultrasonic composite ECoG electrode sequentially comprises a patch type ultrasonic transducer layer and an ECoG electrode layer from top to bottom, the ECoG electrode layer is provided with a hole, and the hole is filled with an ultrasonic coupling agent. According to the electroencephalogram-ultrasonic composite ECoG electrode, the effects of ECoG signal collection and ultrasonic focusing stimulation can be achieved at the same time, it is guaranteed that the ECoG electrode with the spatial position closer to the brain cannot shield the patch type ultrasonic transducer by arranging the holes, and function expansion of an integrated device is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of medical devices, and in particular relates to an electroencephalogram-ultrasound composite ECoG electrode. Background Art

[0002] EEG is the basic characteristic of brain neural activity, reflecting the physiological state and information encoding of neurons. Brain electrodes are electronic devices that record the electrophysiological activity of neurons and are important tools for studying EEG. Brain electrodes are divided into three types according to the degree of invasiveness: non-invasive scalp EEG electrodes (EEG), semi-invasive cortical EEG electrodes (ECoG) and invasive deep EEG electrodes (DPS). Among them, ECoG electrodes are placed directly on the surface of the cerebral cortex, and the recorded signals are less shielded by the skull, so the resolution is higher than that of EEG; at the same time, the electrodes are not directly inserted into the brain tissue, so the damage caused is less than that of invasive electrodes, and they can often maintain a relatively longer stable recording time, and have been widely used in medical diagnosis and brain-computer interface research. For example, a flexible patch-type EcoG electrode array that supports synchronous acquisition of EIT and EEG signals is disclosed in a Chinese patent with publication number CN219109442U, including a circuit board, a skull pin, an interface, and a wire. The skull pin and the interface are both located on the circuit board, and the skull pin is connected and connected to the interface through the circuit board.

[0003] Although ECoG electrodes have advantages in recording and studying brain electrical activity, they are usually located on the surface of the brain, making it difficult to stimulate deep structures during treatment. In addition, the functions that a single ECoG electrode can achieve are relatively limited. There is still room for research on how to add modules with other diagnostic and treatment functions to the limited patch structure and expand the functions of the integrated device.

[0004] Focused ultrasound therapy can be precisely focused on a specific area in the brain, and produce a local thermal effect by controlling the intensity and focal point of ultrasound waves. It has shown obvious advantages in the treatment of diseases such as tumors, epilepsy, and movement disorders, and this therapy can be achieved through a patch-type ultrasonic transducer with a relatively small thickness. For example, the Chinese patent with publication number CN117503405A discloses an implantable ultrasonic device for accelerating fracture healing, including an external ultrasonic transducer and an implantable ultrasonic patch, the implantable ultrasonic patch including a piezoelectric transducer, a polyimide substrate, a flexible control circuit, a serpentine wire, an interdigitated electrode, and a flexible packaging layer; wherein the external ultrasonic transducer is a lead zirconate titanate piezoelectric ceramic, which is responsible for providing ultrasonic waves to the implantable ultrasonic patch.

[0005] Common focused ultrasound devices are often installed outside the skull. Most of the energy will be reflected and absorbed when passing through the skull, resulting in only about 10% of the ultrasound energy passing through the skull. This results in high power consumption, severe heat generation, and inaccurate focusing. Therefore, how to reduce the loss of patch-type ultrasound transducers is also a technical problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of the present invention is to provide an electroencephalogram-ultrasound composite ECoG electrode, which can simultaneously achieve the effects of ECoG signal acquisition and ultrasonic focused stimulation, and solve the problem that ECoG electrode devices are difficult to achieve stimulation with a certain depth.

[0007] The present invention provides the following technical solutions:

[0008] A EEG-ultrasound composite ECoG electrode comprises, from top to bottom, a patch-type ultrasonic transducer layer and an ECoG electrode layer, wherein the ECoG electrode layer is provided with holes filled with an ultrasonic coupling agent.

[0009] The ECoG electrode layer is used to detect ECoG electroencephalogram signals, the patch-type ultrasonic transducer layer is used to realize the focused ultrasonic stimulation function, and the coupling agent is used to enhance the propagation efficiency of ultrasonic waves between human tissue and the ultrasonic transducer. The coupling agent and the patch-type ultrasonic transducer layer can also reduce the loss.

[0010] The hole position of the ECoG electrode layer is below the effective part of the patch-type ultrasonic transducer.

[0011] The thickness of the ECoG electrode is 1 to 1000 μm.

[0012] The patch-type ultrasonic transducer comprises a substrate on which a top electrode and a bottom electrode are arranged, and a piezoelectric sheet connected to the top electrode and the bottom electrode is mounted on the substrate, and the position of the piezoelectric sheet corresponds to the hole on the ECoG electrode layer.

[0013] The thickness of the patch type ultrasonic transducer is 1 to 2000 μm.

[0014] The method for assembling the electroencephalogram-ultrasound composite ECoG electrode comprises: assembling an ECoG electrode layer provided with holes and a patch-type ultrasonic transducer layer, and then adding an ultrasonic coupling agent.

[0015] The ECoG electrode layer and the patch-type ultrasonic transducer are bonded with double-sided adhesive tape, and the thickness of the double-sided adhesive tape is 1 to 1000 μm.

[0016] When in use, the electroencephalogram-ultrasound composite ECoG electrode is located between the skull and the cerebral cortex, wherein the ECoG electrode layer is closely attached to the cerebral cortex.

[0017] The composite ECoG electrode provided by the present invention can be placed under the skull and has lower loss than a patch-type ultrasonic transducer layer placed outside the skull.

[0018] The beneficial effects of the present invention are as follows:

[0019] Under the premise of retaining the advantages of cortical brain electrodes not directly damaging brain tissue and being able to collect ECoG signals in a low-invasive manner, the present invention can simultaneously achieve the effects of ECoG signal collection and ultrasonic focused stimulation through the composite design of the patch-type ultrasonic transducer layer and the ECoG electrode layer, and the patch-type ultrasonic transducer layer has good compatibility with the ECoG electrode structure attached to the surface of the cerebral cortex, thereby realizing the functional expansion of the integrated device; and by arranging holes in the ECoG electrode layer, it is ensured that the ECoG electrode that is spatially closer to the brain will not block the patch-type ultrasonic transducer layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention, the following briefly introduces the drawings required for the embodiments or the prior art description. Obviously, the drawings described below are only examples. For ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0021] The structures, proportions, sizes, etc. shown in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportion or adjustment of size should still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0022] Figure 1 This is a schematic diagram of the structure of an electroencephalogram-ultrasound composite ECoG electrode provided in an embodiment.

[0023] Figure 2 A cross-sectional side view of an electroencephalogram-ultrasound combined ECoG electrode provided in an embodiment.

[0024] Figure 3 This is a flow chart for preparing the patch-type ultrasonic transducer layer included in the electroencephalogram-ultrasound composite ECoG electrode provided in the embodiment.

[0025] Figure 4 This is a photo of the electroencephalogram-ultrasound composite ECoG electrode provided in the embodiment.

[0026] In the figure: 1-ECoG electrode layer, 2-patch type ultrasonic transducer layer, 3-ultrasonic coupling agent, 4-effective part. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments. Here, the embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to be limiting of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0028] Example

[0029] The ECoG electrode provided in this embodiment includes a patch-type ultrasonic transducer layer 2 and an ECoG electrode layer 1 from top to bottom. The ECoG electrode layer 1 is provided with holes filled with an ultrasonic coupling agent 3. Figure 1 The cross-sectional side view when in use is as shown in Figure 2 As shown, the ECoG electrode layer 1 and the ultrasonic coupling agent 3 are in direct contact with the cerebral cortex; the patch-type ultrasonic transducer layer 2 is arranged outside the ECoG electrode layer 1 and the ultrasonic coupling agent 3, the holes of the ECoG electrode layer 1 are directly opposite to the effective part 4 of the patch-type ultrasonic transducer layer 2, and the contacts 5 of the ECoG electrode layer 1 are tightly fitted with the cortex.

[0030] like Figure 3 As shown, the patch type ultrasonic transducer layer 2 provided in this embodiment is formed by welding a 1-3 type piezoelectric transducer and an electrode processed by PZT-5H ceramic and epoxy resin, and the manufacturing method includes steps S1 to S5:

[0031] S1. Use a dicing machine to make horizontal grooves in two perpendicular directions on the polarized PZT-5H ceramic to obtain a ceramic column array with a certain area.

[0032] S2. Pour uncured epoxy resin between the ceramic column arrays and allow it to cure.

[0033] S3. Grind the ungrooved parts and other redundant parts to obtain a 1-3 type piezoelectric sheet.

[0034] S4. Design and weld the ultrasonic top and bottom electrodes according to the required vibrator size and shape. The top electrode contains multiple channels and is welded with low-temperature solder paste, which is mainly used to apply different electrical excitations to different vibrators; the bottom electrode plays a common ground role, is connected to the pad with silver epoxy resin, and can also act as a backing layer.

[0035] S5. After glue filling and packaging, the patch type ultrasonic transducer layer 2 can be obtained.

[0036] In this embodiment, the thickness of the ECoG electrode 1 is 1 to 1000 μm, the thickness of the patch type ultrasonic transducer 2 is 1 to 2000 μm, and the ECoG electrode layer 1 and the patch type ultrasonic transducer layer 2 can be bonded with double-sided tape, and the thickness of the double-sided tape can be 1 to 1000 μm.

[0037] Figure 4 This is a real photo of this embodiment.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the structure, proportion, size, etc. of the present invention may be subject to various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An electroencephalogram-ultrasound composite ECoG electrode, characterized in that: The electroencephalogram-ultrasound composite ECoG electrode comprises, from top to bottom, a patch-type ultrasonic transducer layer and an ECoG electrode layer, wherein the ECoG electrode layer is provided with holes filled with an ultrasonic coupling agent.

2. The electroencephalogram-ultrasound combined ECoG electrode according to claim 1, characterized in that: The hole position of the ECoG electrode layer is below the effective part of the patch type ultrasonic transducer layer.

3. The electroencephalogram-ultrasound combined ECoG electrode according to claim 1, characterized in that: The thickness of the ECoG electrode is 1 to 1000 μm.

4. The electroencephalogram-ultrasound combined ECoG electrode according to claim 1, characterized in that: The thickness of the patch type ultrasonic transducer is 1 to 2000 μm.

5. The electroencephalogram-ultrasound combined ECoG electrode according to claim 4, characterized in that: The patch-type ultrasonic transducer comprises a substrate on which a top electrode and a bottom electrode are arranged, and a piezoelectric sheet connected to the top electrode and the bottom electrode is mounted on the substrate, and the position of the piezoelectric sheet corresponds to the hole on the ECoG electrode layer.

6. The electroencephalogram-ultrasound combined ECoG electrode according to claim 1, characterized in that: The method for assembling the electroencephalogram-ultrasound composite ECoG electrode comprises: assembling an ECoG electrode layer provided with holes and a patch-type ultrasonic transducer layer, and then adding an ultrasonic coupling agent.

7. The electroencephalogram-ultrasound combined ECoG electrode according to claim 1, characterized in that: The ECoG electrode layer and the patch-type ultrasonic transducer are bonded with double-sided adhesive, and the thickness of the double-sided adhesive is 1 to 1000 μm.

8. The electroencephalogram-ultrasound combined ECoG electrode according to any one of claims 1 to 7, characterized in that: When in use, the electroencephalogram-ultrasound composite ECoG electrode is located between the skull and the cerebral cortex, wherein the ECoG electrode layer is closely attached to the cerebral cortex.

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