An implantable electrical stimulation system and control method

Abstract

The present application relates to an implantable electrical stimulation system and a control method. The system comprises an electrode assembly, the electrode assembly comprising a stress release section for buffering stress transmitted from the tail end of the electrode assembly and at least one contact; the stimulation section and the stress release section are connected according to a bending angle. The system further comprises a processing unit configured to, based on the measurement of the activity in the brain region of the patient, control the pulse generator to generate stimulation pulses in a first time sequence; in a second time sequence, update the electrical stimulation scheme to a second stimulation parameter set based on the degree of coincidence between the feedback information of the activity in the brain region of the patient and the expected activity information; in a third time sequence, control the at least one contact remaining to the patient to electrically stimulate the patient to regulate the state of the patient to a normal state in the third stimulation parameter set. The present application combines the electrode structure conforming to the physiological characteristics and the adaptive pulse control.

Description

[0001] The original basis for this divisional application is patent application No. 202310501240.9, filed on May 5, 2023, entitled "A Trigeminal Glandular Stimulation System and its Pulse Control Method". Technical Field

[0002] This invention relates to the field of trigeminal nerve stimulation technology, and more particularly to an implantable electrical stimulation system and control method. Background Technology

[0003] Trigeminal neuropathic pain syndromes, also known as painful trigeminal neuropathy or atypical facial pain, are commonly seen in cases of facial herpes zoster infection, brainstem (or thalamic region) hemorrhage or infarction, multiple sclerosis, damage to the peripheral branches of the trigeminal nerve, and painful numbness after radiofrequency ablation of the trigeminal ganglion. Symptoms include persistent facial pain or paroxysmal exacerbations, accompanied by facial numbness or weakness of the masticatory muscles. Local sensory loss, hyperalgesia, or hyperalgesia may also occur. Microvascular decompression surgery is not effective for trigeminal neuropathic pain; radiofrequency ablation of the trigeminal ganglion leaves long-term numbness with uncertain efficacy; stereotactic ablation of the trigeminal thalamus is not routinely performed due to high surgical risks and numerous complications.

[0004] In terms of neuromodulation, high cervical spinal cord electrical stimulation has been considered for the treatment of trigeminal neuralgia, but there is a lack of clear clinical efficacy evidence. Electrical stimulation of the peripheral branches of the trigeminal nerve has also been used to treat trigeminal neuralgia, and it has a definite effect on pain in the V1 region. However, stimulation of V2 and V3 has disadvantages such as inconsistent electrode stimulation effect, excessive electrode travel distance, affecting appearance, and thin subcutaneous tissue that is prone to local ulceration.

[0005] A new treatment for neuropathic pain, involving electrical stimulation of the dorsal root ganglion of the spinal nerve, is about to be implemented. The trigeminal ganglion is functionally similar to the dorsal root ganglion of the spinal nerve. In recent years, trigeminal ganglion stimulation (TGGS) has gradually become an effective treatment for trigeminal neuralgia. Theoretically, TGGS targets the cell bodies of first-order sensory neurons, resulting in a more precise effect than stimulation of the peripheral branches of the trigeminal nerve, and a single electrode can cover all branches of the trigeminal nerve. Practical application has also confirmed the effectiveness of TGGS. Currently, there is no dedicated electrode assembly for TGGS, and a dedicated stimulation electrode is lacking. Traditional spinal cord stimulation puncture electrodes have several problems, such as numerous contacts, large contact spacing, and a mismatch between the number of contacts at the electrode tip and the morphology of the ganglion, making them unsuitable for TGGS. Especially for conventional trigeminal ganglion electrical stimulation methods, the stimulation electrode is inserted through the foramen ovale via a puncture approach near the corner of the patient's mouth. The puncture direction is not completely parallel to the long axis of the ganglion, exhibiting an angle that leads to inaccurate electrical stimulation. Furthermore, the electrode insertion point is at the corner of the mouth, where the mandible's mobility is high during chewing, easily causing electrode displacement. Therefore, it is necessary to choose a site to anchor the electrode tail. If the electrode is anchored to the maxillary bone using current techniques, it requires incising the gums and dissecting the maxillary soft tissue, posing a significant risk of infection. It should also be noted that the ganglion is located in Meckel's capsule, surrounded by cerebrospinal fluid. Preventing cerebrospinal fluid leakage through the electrode channel, causing refractory hypotension, is also a problem that current techniques need to address.

[0006] Chinese patent CN114099945A relates to a dual-contact needle electrode for stimulating the trigeminal ganglion. This electrode includes a catheter with a guidewire inside. One end of the catheter is connected to a first and a second connecting ring, and the other end is connected to a first and a second platinum-iridium ring. The guidewire is formed by two synchronously wound strands. This dual-contact needle electrode offers precise stimulation of the trigeminal ganglion, allowing for small-area, precise stimulation. It allows selection of the lowest stimulation parameters with maximum benefit and minimal side effects, solving problems that many commonly used structures cannot address. This enhances patient comfort and treatment success rate, and improves the accuracy of treatment effects. However, the patent has a drawback: the electrode site and the subsequent extension line are designed with a bending angle, making it difficult for the electrode to enter the patient's foramen ovale. Even if it does enter, the electrode is prone to penetrating too deeply into the skull base of the trigeminal ganglion, potentially causing damage to the brainstem at the electrode tip. The electrode lacks an anchoring method and does not explain how to address the anchoring issue between the electrode and the patient's body. During activities such as chewing, the electrode is highly susceptible to displacement, failing to properly stimulate the trigeminal ganglion. Furthermore, the electrode does not consider the fact that the trigeminal ganglion is located in Meckel's capsule, surrounded by cerebrospinal fluid, which can easily leak through the electrode channel, causing refractory low intracranial pressure in the patient.

[0007] Chinese patent CN114555177A relates to a system and method for applying electrical stimulation to achieve sustained relief of chronic pain. It includes a coiled percutaneous lead configured to be inserted into a body portion near a pain area and electrodes integrally formed on the coiled percutaneous lead. The electrodes are configured to be positioned internally within the body and at a therapeutically effective distance from a portion of at least one peripheral nerve innervating the pain area. The system and method may further include an electrical stimulation device operatively coupled to the lead to apply electrical stimulation to at least one peripheral nerve innervating the pain area via at least one electrode. This activates target peripheral nerve fibers while preventing activation of non-target peripheral nerve fibers and avoiding alteration or blockage of neural activity in non-target peripheral nerve fibers of at least one peripheral nerve, thereby creating comfort in the pain area and producing pain relief by modulating pain-associated central nervous system plasticity. However, this patent does not specifically address the physiological structure of the trigeminal nerve with corresponding electrode placement, leading to various problems when used for trigeminal nerve electrical stimulation, including cerebrospinal fluid extravasation and electrode anchoring.

[0008] Furthermore, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the applicant studied a large number of documents and patents when making this invention, but due to space limitations, not all details and contents were listed in detail. However, this does not mean that the present invention does not possess the features of these prior art. On the contrary, the present invention already possesses all the features of the prior art, and the applicant reserves the right to add relevant prior art to the background art. Summary of the Invention

[0009] Currently, there are no electrode components specifically designed for electrical stimulation of the trigeminal ganglion, and a lack of dedicated stimulation electrodes for this purpose. Traditional spinal cord stimulation puncture electrodes suffer from several problems, including numerous contacts, large contact spacing, and a mismatch between the number of contacts at the electrode tip and the morphology of the ganglion, making them unsuitable for trigeminal ganglion electrical stimulation. In particular, conventional methods for trigeminal ganglion electrical stimulation, which involve inserting the stimulation electrode through the foramen ovale via a puncture approach near the corner of the patient's mouth, result in the puncture direction not being perfectly parallel to the long axis of the ganglion, exhibiting an angle that leads to inaccurate electrical stimulation.

[0010] To address the shortcomings of existing technologies, this invention provides a trigeminal ganglion stimulation system, comprising an electrode assembly. The electrode assembly includes a stress-relieving segment for buffering stress transmitted from its distal end and at least one contact point, the at least one of which is configured to be placed in a first region of the patient's trigeminal nerve. Preferably, the electrode assembly is configured to, when inserted into the patient's trigeminal ganglion via a foramen ovale, be close to, adjacent to, or in contact with at least one branch of the patient's trigeminal nerve, and to perform neuromodulation by electrically stimulating the patient's trigeminal nerve. The electrode assembly of this invention is implanted at the patient's foramen ovale, and due to the stimulation array arrangement of its contacts and the special design of each structure, it can be fixed at the foramen ovale. Stimulation of the patient's trigeminal ganglion using the electrode assembly can treat various medical conditions such as facial pain. The electrode assembly is placed within the patient's trigeminal ganglion to perform electrical stimulation within a predetermined set of stimulation parameters, and the stimulation parameters can be further refined and updated based on factors such as the patient's medical history, the disease to be treated, or the individual's sensitivity to stimulation.

[0011] According to a preferred embodiment, the electrode assembly further includes a stimulation segment for performing electrical stimulation. Preferably, a plurality of the contacts are electrically connected together to form a stimulation array located on the stimulation segment that collectively provides electrical stimulation. The electrode assembly of the present invention does not require additional anchoring of the electrode tail end, avoiding electrode position movement and thus reducing the risk of secondary injury or infection to the patient.

[0012] According to a preferred embodiment, the stimulation segment and the stress relief segment are connected by a bending angle. Preferably, the extension lines of the stimulation segment and the stress relief segment intersect to form the bending angle, such that the stress relief segment, which serves as the main long axis of the electrode assembly, and the stimulation segment used for electrical stimulation are parallel to the long axes of the patient's semilunar ganglion and foramen ovale, respectively. This bending angle design conforms to the patient's physiological characteristics, maximizes effective coverage of electrical stimulation, and prevents breakage caused by long-term stress at the angled portion of the electrode.

[0013] According to a preferred embodiment, the stress-relieving section remains vertical when the guidewire is inserted, and transforms into a ring-shaped curved structure after the guidewire is removed. Preferably, the ring-shaped curved structure consists of at least two rings to buffer the stress transmitted from the patient's oral movements and increase the travel distance of the electrode assembly within the patient's foramen ovale. The ring-shaped curved structure buffers the stress transmitted from the tail end of the electrode assembly during the patient's chewing, mouth-opening, and other movements, preventing the electrode assembly from shifting or dislodging. The stress-relieving section increases the travel distance of the electrode assembly within the patient's foramen ovale, reducing the incidence of postoperative extravasation of cerebrospinal fluid from the foramen ovale puncture tract of the electrode assembly.

[0014] According to a preferred embodiment, a plurality of the contacts are annular and embedded in the outer substrate of the electrode assembly. Preferably, the plurality of contacts are connected to the tail end of the electrode assembly by a helix, and are connected to an extension line by corresponding contacts provided on the tail end of the electrode assembly. The helix is, for example, a double-stranded helical metal wire.

[0015] According to a preferred embodiment, the system further includes a pulse generator electrically connected to the electrode assembly. The pulse generator includes a power supply, a pulse generation circuit powered by the power supply, and a controller for generating operating instructions. Preferably, the pulse generation circuit generates stimulation pulses at least in a manner that the controller receives a specified electrical stimulation scheme and generates operating instructions to control the pulse generation circuit.

[0016] According to a preferred embodiment, the electrical stimulation protocol includes at least the frequency, amplitude, and duration of the stimulation pulses applied to the patient. The electrical stimulation protocol may also include pulse width and interval duration. According to a preferred embodiment, the system further includes a processing unit configured to: based on measurements of activity in the patient's brain regions, in a first time sequence, control the pulse generator to generate at least one stimulation pulse with a first set of stimulation parameters to at least one branch nerve within the patient's trigeminal ganglion; in a second time sequence, based on the degree of consistency between feedback activity detection information and expected activity information in the patient's brain regions, update the electrical stimulation protocol to a second set of stimulation parameters and control the stimulation array in the electrode assembly; in a third time sequence, control at least one remaining contact point for electrical stimulation of the patient to modulate the patient's state to a normal state using a third set of stimulation parameters. The advantage is that it can quickly respond to changes in the patient's brain state, appropriately updating and adjusting the stimulation parameter set in the first instance to alleviate the patient's emotional changes, anxiety, pain, etc. At this time, because the patient is at the beginning of a change in brain state, their discomfort is relatively small, thus allowing for rapid treatment with the electrical stimulation protocol. The system can directly determine the degree of consistency between the detected and predicted activity information of the patient's brain regions using a pre-stored database, and quickly generate better or even optimal electrical stimulation protocols and parameter sets. This allows for rapid treatment of the patient's emotional changes, anxiety, pain, etc., while reducing the amount of data processed by the processing unit and minimizing patient discomfort.

[0017] The present invention also relates to pulse control of an electrode assembly for stimulation of the trigeminal ganglion, the method comprising: placing at least one contact point in a first region of the patient's trigeminal nerve; and, in the case of puncture into the patient's trigeminal ganglion via the foramen ovale, placing the electrode assembly close to, adjacent to, or in contact with at least one branch of the patient's trigeminal nerve to perform neuromodulation by electrically stimulating the patient's trigeminal nerve.

[0018] According to a preferred embodiment, the method further includes: generating stimulation pulses in a manner that the specified electrical stimulation scheme is received by the instruction receiver and generated as an operation instruction for controlling the pulse generation circuit. Attached Figure Description

[0019] Figure 1 This is a simplified schematic diagram of the module connection relationship of a trigeminal ganglion stimulation system according to a preferred embodiment of the present invention; Figure 2 This is a simplified structural diagram of an electrode assembly according to a preferred embodiment of the present invention; Figure 3 This is a simplified structural diagram of the bending angle of an electrode assembly according to a preferred embodiment of the present invention.

[0020] List of reference numerals 1: Electrode assembly; 2: Stimulation section; 3: First contact; 4: Second contact; 5: Third contact; 6: Fourth contact; 7: Stress relief section; 8: Processing unit; 9: Bending angle. Detailed Implementation

[0021] The following is a detailed explanation with reference to the accompanying drawings.

[0022] Example 1 For patients with trigeminal neuralgia, trigeminal gasserian ganglion stimulation (TGGS) is gradually becoming an effective treatment method. Its effectiveness has been proven in practice, but currently, there is a lack of dedicated TGGS electrodes, and traditional spinal cord stimulation electrodes are generally used as a substitute. However, spinal cord stimulation electrodes have more contacts, larger contact spacing, and the number of contacts at the electrode tip does not match the morphology of the trigeminal ganglion. Furthermore, although TGGS represents a significant advancement over previous treatments for trigeminal neuralgia, such as microvascular decompression surgery and stereotactic trigeminal thalamic tract ablation, further improvements are still needed.

[0023] For example, when using implantable electrode contacts for stimulation, an efficient and safe mechanism is still required to connect the electrode contacts to a suitable pulse generator via electrical stimulation (or optical or magnetic). If the pulse generator is located outside the patient's body (non-implantable), the connecting wires to the electrode contacts must pass through the patient's skin (which can cause unpredictable harm to the patient over time due to infection and other issues), or some signal coupling mechanism, such as inductive or radio frequency coupling, must be used to allow the pulses generated by the pulse generator to be effectively transmitted to the electrode array and the specific electrode contacts contained within the electrode array. If the pulse generator is implanted, cables or leads must be run from the pulse generator's implantation site through the patient's body tissue to the electrode contact's implantation site. Connecting wires through the patient's body tissue, especially long-distance connections, exposes the patient to the same post-operative risks as major surgery, and can cause even more serious harm in the event of wire failure or breakage. Therefore, it can be seen that despite advancements in the treatment techniques for trigeminal neuralgia, further improvements are still needed.

[0024] This invention relates to an implantable electrical stimulation system, and more particularly to a trigeminal ganglion stimulation system. The invention treats trigeminal neuralgia by applying stimulation pulses from an electrode assembly 1 at a specific location on the patient. Key components of the invention are a pulse generator and an electrode assembly 1. Preferably, the system includes: a pulse generator; and an electrode assembly 1 electrically connected to the pulse generator. The electrode assembly 1 includes a stress-relieving section 7 for buffering stress transmitted from the distal end of the electrode assembly 1 and at least one contact. The at least one contact is configured to be placed in a first region of the patient's trigeminal nerve. The contact is, for example, a metallic marker. Preferably, the electrode assembly 1 is configured to, when inserted into the patient's trigeminal ganglion via a foramen ovale, be close to, adjacent to, or in contact with at least one branch of the patient's trigeminal nerve, for neuromodulation by electrical stimulation of the patient's trigeminal nerve. The pulse generator includes a power source, a pulse generation circuit powered by the power source, and a controller for generating operating instructions. The pulse generation circuit generates stimulation pulses at least in part according to a manner in which the controller receives a specified electrical stimulation scheme and generates operating instructions to control the pulse generation circuit. Electrode assembly 1 includes a stimulation segment 2 for electrical stimulation and a stress relief segment 7 for buffering stress transmitted from the tail end of electrode assembly 1. At least one contact is disposed on stimulation segment 2 and placed in a first region of the patient's trigeminal nerve. A plurality of contacts are electrically connected together to form a stimulation array located on stimulation segment 2 that works together. Stimulation pulses generated by a pulse generator are directed to the stimulation array. Thus, based on a specified electrical stimulation protocol, stimulation pulses are applied to the patient's tissue region through the stimulation array composed of a plurality of contacts. The aforementioned electrical stimulation protocol defines the frequency, pulse width, intensity, and duration of each stimulation pulse applied to the patient. Furthermore, the electrical stimulation protocol requires a low duty cycle for the electrical stimulation treatment of the patient. More specifically, if the duration of the stimulation pulse is T1 minutes and stimulation is performed at a frequency of once every T2 minutes, the duty cycle or T1 / T2 ratio is less than 0.05. It should be noted that the patient tissue location (or first region) where the stimulation pulses are applied in this invention includes at least one of the three branches of the trigeminal nerve. The aforementioned first region is, for example, the body region of the patient's trigeminal ganglion. The patient tissue locations where stimulation pulses are applied in this invention also include: ophthalmic nerve, supraorbital nerve, infraorbital nerve, nasociliary nerve, supratrochlear nerve, mental nerve, and auriculotemporal nerve.

[0025] The trigeminal ganglion stimulation system of the present invention is used to treat patients with at least one of the following mental disorders or neurological diseases: trigeminal neuralgia, post-traumatic stress disorder, obsessive-compulsive disorder, major depressive disorder, and generalized anxiety disorder.

[0026] According to a preferred embodiment, the connection between the stimulation segment 2 and the stress relief segment 7 is pre-bent. The stimulation segment 2 and the stress relief segment 7 are connected at a bending angle 9. Preferably, the stimulation segment 2 is smoothly bent at 20°~40°. The bending angle 9 formed by the intersection of the extension lines of the stimulation segment 2 and the stress relief segment 7 is 20°~40°, preferably 30°. The stress relief segment 7, as the main long axis of the electrode assembly 1, forms an obtuse angle of 140°~160°, preferably 150°, with the stimulation segment 2 at the front end of the electrode assembly 1, so that the stimulation segment 2 is completely parallel to the long axis of the patient's foramen ovale. Generally, the long axis of the patient's foramen ovale and the long axis of the semilunar junction form approximately 150°. This bending angle 9 is designed to conform to the patient's physiological characteristics, maximizing the effective coverage of electrical stimulation.

[0027] According to a preferred embodiment, the 15mm tip of the electrode assembly 1 is designated as the stimulation segment 2. Preferably, the diameter of the stimulation segment 2 is 1mm. Figure 2 As shown, at least four contacts are provided on the stimulation segment 2. From the end of the electrode assembly 1 to the tail of the stimulation segment 2, they are respectively labeled as first contact 3, second contact 4, third contact 5, and fourth contact 6. The first contact 3 has a 1mm margin at its front end. Preferably, each contact is 2mm long, and the spacing between stimulation points is 2mm.

[0028] According to a preferred embodiment, the 20mm-30mm portion of the tail end of the electrode assembly 1 is designed as a stress-relieving section 7. Preferably, the stress-relieving section 7 remains vertical when a guidewire is present within the electrode assembly 1, and transforms into a ring-shaped curved structure, i.e., a spring structure, after the guidewire is removed from the electrode assembly 1. The ring-shaped curved structure of the stress-relieving section 7 consists of at least two rings to buffer the stress transmitted from the tail end of the electrode assembly 1 during patient chewing, mouth opening, and other actions, preventing the electrode assembly 1 from shifting or dislodging. Preferably, after transforming into a ring-shaped curved structure, the stress-relieving section 7 is located at the patient's foramen ovale. The stress-relieving section 7 increases the travel distance of the electrode assembly 1 within the patient's foramen ovale, reducing the incidence of postoperative extravasation of cerebrospinal fluid from the foramen ovale puncture tract of the electrode assembly 1. Preferably, metal positioning marks are also provided at the 20mm and 30mm portions of the tail end of the electrode assembly 1 to facilitate intraoperative X-ray fluoroscopy positioning and determination of the position of the stress-relieving section 7 after guidewire removal. This location is generally at the base of the skull, from the internal opening of the foramen ovale to the semilunar ganglion. If it is too deep, there is a risk of damage to the brainstem at the tip of electrode assembly 1.

[0029] According to a preferred embodiment, the electrode assembly 1 is made primarily of silicone or other non-corrosive soft matrix material, and is hollow with a guide wire. Preferably, the contacts are annular and embedded in the matrix of the electrode assembly 1. Preferably, the contacts are connected to the tail of the electrode assembly 1 by a helical wire. This helical wire is, for example, a double-stranded spiral metal wire. Figure 2As shown, the electrode assembly 1 also has four contacts at its tail end, and is seamlessly connected to the extension line. The aforementioned spiral is, for example, a spiral metal wire, a double-strand spiral metal wire, or a spiral or metal wire of other materials.

[0030] The electrode assembly 1 of this invention is implanted at the foramen ovale of the patient. Due to the stimulation array arrangement of its contacts and the special design of each structure, it can be fixed at the foramen ovale. Currently, there is no electrode assembly 1 specifically designed for electrical stimulation of the trigeminal ganglion, and there is a lack of dedicated stimulation electrodes for this purpose. Traditional spinal cord stimulation puncture electrodes have several problems, such as a large number of contacts, large contact spacing, and a mismatch between the number of contacts at the electrode tip and the morphology of the ganglion, making them unsuitable for trigeminal ganglion electrical stimulation. In particular, for conventional trigeminal ganglion electrical stimulation methods, the stimulation electrode is inserted through the foramen ovale via a puncture approach near the corner of the patient's mouth. The puncture direction is not completely parallel to the long axis of the ganglion, resulting in an angle that leads to inaccurate electrical stimulation. Furthermore, the electrode puncture point is located at the corner of the mouth, and the large range of motion of the mandible during chewing can easily cause electrode displacement, necessitating the selection of a site to anchor the electrode tail. Some studies have anchored electrodes to the maxillary bone of patients, which requires cutting the gums and dissecting the soft tissue of the maxilla, posing a high risk of infection. It should also be noted that the semilunar ganglion is located in Meckel's sac and is surrounded by cerebrospinal fluid. How to prevent cerebrospinal fluid from leaking out through the electrode channel and causing refractory low intracranial pressure is also a problem that current technology needs to solve.

[0031] Therefore, in view of the above situation, the present invention proposes an electrode assembly 1 specifically for electrical stimulation of the trigeminal ganglion, and a method for performing electrical stimulation using the electrode assembly 1.

[0032] The method of performing trigeminal ganglion electrical stimulation surgery using the electrode assembly 1 of the present invention involves dividing the trigeminal ganglion electrical stimulation surgery into at least two steps. Specifically: S1: Puncture through the patient's oral cavity, puncture through the foramen ovale into the semilunar junction, and then insert electrode assembly 1.

[0033] Preferably, intraoral puncture is used to implant the electrode assembly 1, abandoning the traditional puncture technique next to the corner of the patient's mouth. This avoids the problem that the puncture direction is not parallel to the long axis of the patient's semilunar segment, and also avoids the problem that the large range of motion of the mandible during chewing can easily cause the electrode assembly 1 to shift.

[0034] Step S1 includes at least the following steps S101 to S103.

[0035] Step S101: Puncture through the patient's oral cavity, through the foramen ovale into the semilunar ganglion, leaving a puncture point for inserting electrode assembly 1.

[0036] Preferably, step S102: the tail end of the electrode assembly 1 is inserted into the incision behind the patient's ear using a subcutaneous tunneling device.

[0037] More specifically regarding step S102, step S102 includes at least: making a 1cm incision at the puncture point, inserting the tail end of the electrode assembly 1 into the incision behind the patient's ear through a subcutaneous tunneling device, and connecting it to an extension line.

[0038] More preferably, an additional perforation is made to allow the extension line to pass through the patient's skin.

[0039] Step S103: Connect the extension line to the external stimulator for testing. If the electrical stimulation method can correctly stimulate the trigeminal ganglion of the patient, proceed to step S2.

[0040] S2: Remove the extension cable and insert the tail end of electrode assembly 1 into the patient's subclavian bone via a subcutaneous tunneling device. Place a pulse generator under the patient's clavicle and connect it to electrode assembly 1.

[0041] This invention treats various medical conditions in patients by stimulating the trigeminal ganglion with an electrode assembly 1. These conditions may include, but are not limited to, neuropsychiatric disorders, nervous system disorders, heart-related diseases, fatigue, tinnitus, obstructive sleep apnea, trigeminal neuralgia, post-traumatic stress disorder, obsessive-compulsive disorder, major depressive disorder, and generalized anxiety disorder. More specifically, this invention discloses an implantable electrode assembly 1 and a system for trigeminal nerve stimulation. As described in more detail, the electrode assembly 1 is not placed near critical structures such as the carotid artery or jugular vein. The electrode assembly 1 is directly or physically attached or fixed to the patient's foramen ovale and trigeminal ganglion, and a stress-relieving section 7 increases the travel distance of the electrode assembly 1 within the foramen ovale to prevent potential problems such as cerebrospinal fluid leakage and infection. The electrode assembly 1 is placed within the trigeminal ganglion to provide electrical stimulation within a predetermined set of stimulation parameters, which can be further refined and updated based on factors such as patient history, the disease to be treated, or individual sensitivity to stimulation. As is the case with the electrode assembly 1 of the present invention, there is no need to additionally anchor the electrode tail end, thus avoiding electrode position movement and reducing the risk of secondary injury or infection to the patient.

[0042] According to a preferred embodiment, the system further includes a processing unit 8. The processing unit 8 stimulates the patient's trigeminal nerve with a minimum current. Preferably, the processing unit 8 determines the electrical stimulation of at least one branch nerve within the patient's trigeminal ganglion based on measurements of activity in the patient's brain region to detect acute physiological changes in the patient. Based on the above, the present invention provides a preferred embodiment in which the processing unit 8, based on measurements of activity in the patient's brain region, controls a pulse generator to generate at least one stimulation pulse with a first set of stimulation parameters to at least one branch nerve within the patient's trigeminal ganglion in a first time sequence. In a second time sequence, based on the degree of conformity between the feedback activity detection information in the patient's brain region and the expected activity information, the electrical stimulation scheme is updated to a second set of stimulation parameters, and the stimulation array in the electrode assembly 1 is controlled. In a third time sequence, at least one remaining contact still electrically stimulating the patient is controlled to modulate the patient's state to a normal state using the third set of stimulation parameters. The first, second, and third time sequences have a sequential order.

[0043] The key to this approach is that it doesn't rely on prolonged electrical stimulation with a predetermined set of stimulation parameters. Instead, it updates the stimulation parameters based on feedback from activity detection information in the patient's brain regions. The advantage lies in its ability to quickly respond to changes in the patient's brain state, adjusting the stimulation parameters appropriately in the immediate aftermath to alleviate emotional changes, anxiety, and pain. At this point, because the patient is at the beginning of a change in brain state, their discomfort is relatively minimal, allowing for rapid implementation of the electrical stimulation treatment. This approach obtains activity detection information in the patient's brain regions directly from detectors in contact with the patient's body. For the patient's variable brain region activity, a pre-stored database can directly determine the degree of consistency between the detected activity information and the predicted activity information, quickly generating a better or even optimal electrical stimulation protocol and parameter set. This allows for rapid treatment of the patient's emotional changes, anxiety, and pain while reducing the data processing load of the processing unit and minimizing patient discomfort.

[0044] Preferably, in this invention, the selection of stimulation parameter sets is crucial for the electrical stimulation program for patients, especially for patients with different medical histories, diseases to be treated, and / or individual sensitivities to stimulation. Therefore, the following steps are provided: Processing unit 8 selects an electrical stimulation program with a first stimulation parameter set that matches the patient's medical record based on the medical record database; within a first time sequence, it controls a pulse generator to generate at least one stimulation pulse with the first stimulation parameter set to at least one branch nerve within the patient's trigeminal ganglion; if the activity detection information in the patient's brain deviates from the expected activity information, it determines the electrical stimulation program with a second stimulation parameter set required by the patient based on the activity detection information; according to the determined electrical stimulation program with the second stimulation parameter set, within a second time sequence, it controls the pulse generator to change the electrical stimulation of at least one contact in the stimulation array by updating the stimulation parameters; within a third time sequence, it controls the remaining at least one contact still stimulating the patient to adjust the patient's state to a normal state using the third stimulation parameter set. The aforementioned third stimulation parameter set is derived based on the changes in the patient's activity detection information within the third time sequence.

[0045] According to a preferred embodiment, when multiple detection units for detecting brain activity are installed on the patient's body, the detection target is configured as at least one near-infrared spectral image corresponding to the patient's cerebral cortex and / or the patient's state parameters. This allows the processing unit 8 to determine the patient's activity detection information based on the near-infrared spectral image and / or state parameters. If the activity detection information deviates from the predicted activity information in the medical record database, at least one electrical stimulation protocol is selected based on a traversed medical record database. The patient's state parameters can be selected as, for example, physiological characteristics of the patient's body. In one embodiment, these physiological characteristics may include changes in the patient's heart rate, pulse oxygen saturation, cerebral blood flow, systolic blood pressure, diastolic blood pressure, facial micro-expression changes, and limb tremors. In this case, selecting an electrical stimulation protocol that can alleviate the patient's current symptoms is beneficial for the patient's rapid recovery to a normal state. In another embodiment, these physiological characteristics may also include the presence of factors that may indicate a potentially dangerous condition or a desired clinical effect, such as antihypertensive drugs like tropin and levels of pro-inflammatory cytokines. Processing unit 8 learns from previous responses to the electrical stimulation protocol in a specific patient or similar patients to alleviate the type of disease being treated. This method, which involves qualitative and / or quantitative feedback, can be used by processing unit 8 to automatically or otherwise adjust the stimulation parameter set of the electrical stimulation protocol to optimize the clinical efficacy of the electrical stimulation.

[0046] In existing technologies, electrical stimulation protocols for patients typically employ a fixed protocol tailored to the specific patient's condition. This approach forcibly applies a uniform protocol to all patient symptoms, but it often lacks flexibility, particularly for patients with varying medical histories, underlying diseases, and / or individual sensitivities to stimulation. If the processing unit 8 fails to differentiate its electrical stimulation protocol based on the patient's medical history and real-time changes in their condition, the effectiveness of the protocol may not be proportionally reflected, potentially leading to negative feedback and worsening the patient's condition. Furthermore, deviations from predicted activity levels, especially for patients with specific diseases, often indicate a rapid decline in the patient's condition, requiring immediate and swift treatment to prevent sudden deterioration. However, due to the diversity of the state of the patient's disease mutation, it is difficult to have a method to detect the mutation time point and form a corresponding electrical stimulation program with stimulation parameter set. This ultimately leads to a decrease in the treatment rate of the patient's disease, poor treatment effect, or the patient's disease has been mutated for a considerable period of time before the corresponding treatment plan is adjusted. At this time, the patient's disease may have entered the next stage, which will cause damage to the patient.

[0047] According to a preferred embodiment, when the detection object is a patient's state parameters, the detection unit can be various contact sensors that detect state parameters by being applied to the patient's skin, or various image acquisition sensors that acquire patient image information and convert it into analysis of the patient's actions and / or expressions by the processing unit 8. When the detection object is a near-infrared spectral image, the detection unit can be a near-infrared imaging sensor to acquire a near-infrared spectral image of the patient's cerebral cortex. Activity detection information containing the patient's cerebral cortex activity areas and changes in light absorption parameters can be extracted from the near-infrared spectral image. Because the emotional changes or pain changes that occur after a sudden change in the patient's condition will cause changes in the oxygen consumption value of the corresponding area of ​​the cerebral cortex, resulting in changes in near-infrared spectral absorption. Therefore, changes in the oxygen consumption of the patient's cerebral cortex correspond to changes in the patient's condition. The oxygen consumption value can be directly calculated based on changes in light absorption parameters. For example, the Lambert-Beer law can be used to calculate the oxygenated and deoxygenated hemoglobin values. The processing unit 8 then calculates the oxygen consumption based on the oxygenated and deoxygenated hemoglobin values. Processing unit 8 determines the active areas of the patient's brain based on oxygen consumption, and judges changes in the patient's mood or pain by monitoring these brain activity areas. The predicted activity information consists of sample data of the patient's brain activity areas. The degree of agreement (overlap) is calculated by comparing the brain activity areas in the measured activity information with the sample brain activity areas in the predicted activity information. If the obtained degree of agreement deviates from a threshold range, a sudden change in the patient's condition is confirmed. If the obtained degree of agreement is within the threshold range, the patient's condition is confirmed to be normal.

[0048] A trigeminal ganglion stimulation system based on the above-described technical solution of the present invention is used to treat neurological or psychiatric diseases. More specifically, the system and method disclosed in this invention are designed to treat various medical diseases in patients. It should be understood that the present invention is not limited to treating the above-described medical diseases. As detailed above, the essence of the present invention recognizes the defects of existing electrical stimulation programs and their lack of continuity. Therefore, a specially designed electrode assembly 1 for the trigeminal ganglion is implanted through specific technical means, and continuous low-duty-cycle trigeminal nerve electrical stimulation therapy is provided. The electrical stimulation program of the present invention is adjusted according to the specific disease, condition, or disorder of the patient being treated. The basic implementation method of the present invention includes: determining a basic electrical stimulation method that can be used to treat or regulate a specific disease, condition, or defect exhibited by a patient; implanting the electrode assembly 1 as described above and fixing it in the patient's trigeminal ganglion; applying an electrical stimulation program with low intensity, low frequency, pulse width, and low duty cycle through the electrode assembly 1, so that the electrical stimulation pulses flow through the patient's trigeminal nerve tissue for weeks, months, or years after the electrical stimulation program is set in the processing unit 8. At any point during this electrical stimulation protocol, the patient’s disease, condition, or defect can be assessed, and the set of stimulation parameters applied during the protocol can be adjusted to improve the efficacy and effectiveness of the treatment.

[0049] Exemplary applications of the present invention are described below.

[0050] Major depressive disorder and mood disorders are usually classified as mood or affective disorders. Patients with major depressive disorder are characterized by persistent low mood or sadness, decreased or absent interest in almost all activities, loss of self-confidence, and feelings of worthlessness. Most patients with mood disorders experience alternating episodes of depression and mania. Mania includes euphoria or elevated mood, increased interest in activities, an inflated self-image, and an inflated sense of self-confidence. Both major depressive disorder and mood disorders are episodic.

[0051] The trigeminal nerve electrical stimulation system of this invention can be used to treat major depressive disorder and mood disorders. As previously mentioned, patients with major depressive disorder exhibit symptoms of depressed mood, and corresponding chemical changes occur in the brain under these symptoms. For example, an imbalance of the three monoamine neurotransmitters (serotonin, norepinephrine, and dopamine) is often considered a symptom of major depressive disorder. Trigeminal nerve electrical stimulation can improve depression by balancing serotonin (and norepinephrine) levels in the brain. That is, trigeminal nerve electrical stimulation has an effect on monoamine neurotransmitters in the brain of chronic stress-induced depression.

[0052] To treat any of the aforementioned medical conditions, the processing unit 8 applies electrical stimulation according to a specified electrical stimulation protocol. Preferred patient electrical stimulation sites include at least one site selected from the following group of sites: the three branches of the trigeminal nerve, including the supraorbital, supraorbital, and infraorbital nerves. For patients with major depressive disorder and affective disorder, the electrical stimulation protocol has different stimulation frequencies, durations, and amplitudes. The stimulation frequency varies between 5 Hz and 15 Hz. The processing unit 8 can apply different stimulation frequencies throughout the stimulation process. The entire stimulation process lasts from 30 to 60 minutes, preferably 45 minutes. For example, a suitable electrical stimulation protocol for patients with major depressive disorder and affective disorder is preferably: stimulation at 12 Hz for 10 minutes, stimulation at 10 Hz for 10 minutes, stimulation at 8 Hz for 10 minutes, and stimulation at 6 Hz for 15 minutes, for a total duration of 45 minutes. The amplitude at all frequencies in this electrical stimulation protocol is between 2 mA and 10 mA. This electrical stimulation protocol is performed twice daily. Preferably, electrode assembly 1 can be used to provide an electrical stimulation protocol with the following exemplary settings: a frequency between 1 Hz and 150 Hz, a current between approximately 1 and 25 mA, and a pulse duration between approximately 50 μs and 250 μs, for at least one hour per day. In some embodiments for treating fatigue, patients can use electrode assembly 1 to provide an electrical stimulation protocol with the following exemplary settings: a frequency of 120 Hz, a current of 25 mA, and a pulse duration (pulse width) of 250 μs, for at least 8 hours per day. Preferably, the current amplitude can also be between 2.5 mA and 5 mA. For patient comfort and low power consumption, stimulation parameter sets within the above ranges can be used; differences in clinical efficacy may vary with variations in the range of stimulation parameter sets.

[0053] Throughout the text, the features indicated by “preferred” are only optional and should not be construed as mandatory. Therefore, the applicant reserves the right to abandon or delete the relevant preferred features at any time.

[0054] It should be noted that the specific embodiments described above are exemplary. Those skilled in the art can devise various solutions inspired by the disclosure of this invention, and these solutions all fall within the scope of this invention and its protection. Those skilled in the art should understand that this specification and its accompanying drawings are illustrative and not intended to limit the scope of the claims. The scope of protection of this invention is defined by the claims and their equivalents. This specification contains multiple inventive concepts; terms such as "preferredly," "according to a preferred embodiment," or "optionally" indicate that the corresponding paragraph discloses an independent concept. The applicant reserves the right to file divisional applications based on each inventive concept.

Claims

1. An implantable electrical stimulation system, characterized in that, The system includes: Electrode assembly (1), the electrode assembly (1) includes a stress relief section (7) for buffering stress transmitted from the tail end of the electrode assembly (1) and at least one contact, the at least one of the contacts being configured to be placed in a first region of the patient's trigeminal nerve; A pulse generator, which is electrically connected to the electrode assembly (1); and processing unit (8), which is configured to: Based on measurements of activity in the patient's brain regions, within a first time sequence, the pulse generator is controlled to generate at least one stimulation pulse with a first set of stimulation parameters to at least one branch nerve in the patient's trigeminal ganglion. Within the second time series, based on the degree of consistency between the activity detection information and the expected activity information in the patient's brain region, the electrical stimulation protocol is updated to the second stimulation parameter set and the stimulation array in the electrode assembly (1) is controlled; Within the third time series, at least one of the remaining contacts that provide electrical stimulation to the patient is controlled to modulate the patient's state to a normal state using a third set of stimulation parameters.

2. The implantable electrical stimulation system according to claim 1, characterized in that, The electrode assembly (1) further includes a stimulation segment (2) for performing electrical stimulation, wherein a plurality of the contacts are connected together to form a stimulation array located on the stimulation segment (2) for jointly performing electrical stimulation. The stimulation segment (2) and the stress relief segment (7) are connected by a bending angle (9), wherein the extension line of the stimulation segment (2) and the extension line of the stress relief segment (7) intersect to form the bending angle (9), such that the stress relief segment (7), which is the main long axis of the electrode assembly (1), and the stimulation segment (2) for performing electrical stimulation are parallel to the long axis of the patient's semilunar ganglion and the long axis of the foramen ovale, respectively.

3. The implantable electrical stimulation system according to claim 2, characterized in that, The stress relief section (7) remains vertical when the guide wire is installed, and when the guide wire is removed from the stress relief section (7), the stress relief section (7) transforms into an annular curved structure. The annular curved structure consists of at least two rings to buffer the stress transmitted from the patient’s mouth movements and to increase the travel distance of the electrode assembly (1) within the patient’s foramen ovale.

4. The implantable electrical stimulation system according to claim 1, characterized in that, Several of the contacts are ring-shaped and embedded in the outer matrix of the electrode assembly (1). The several contacts are connected to the tail end of the electrode assembly (1) by a spiral line and are connected to an extension line by a corresponding several contacts provided on the tail end of the electrode assembly (1).

5. The implantable electrical stimulation system according to claim 1, characterized in that, The processing unit (8) is configured as follows: Based on the medical record database, select an electrical stimulation protocol with the first stimulation parameter group that matches the patient's medical record; If the activity detection information in the patient's brain deviates from the expected activity information, the electrical stimulation protocol with a second set of stimulation parameters is determined based on the activity detection information. According to the determined electrical stimulation scheme with a second set of stimulation parameters, within a second time sequence, the control pulse generator is used to change the electrical stimulation of at least one contact in the stimulation array in a manner that updates the stimulation parameters.

6. The implantable electrical stimulation system according to claim 5, characterized in that, In the case where multiple detection units for detecting activity information in the brain are set on the patient's body, the detection object is configured as at least one near-infrared spectral image corresponding to the patient's cerebral cortex and / or the patient's state parameters, so that the processing unit (8) judges the patient's activity detection information based on the near-infrared spectral image and / or state parameters, and selects at least one electrical stimulation scheme based on the traversed medical record database when the activity detection information deviates from the expected activity information in the medical record database.

7. The implantable electrical stimulation system according to claim 6, characterized in that, When the object to be detected is a near-infrared spectral image, the detection unit can be a near-infrared imaging sensor to acquire near-infrared spectral images of the patient's cerebral cortex; The processing unit (8) is configured as follows: The Lambert-Beer law is used to calculate the oxygenated and deoxygenated hemoglobin values; Oxygen consumption is calculated based on oxygenated and deoxygenated hemoglobin levels. Based on oxygen consumption, the active areas of the patient's brain are determined, and the changes in the patient's mood or pain are judged by monitoring the active areas of the brain.

8. The implantable electrical stimulation system according to claim 1, characterized in that, The first region is the body region of the patient's trigeminal ganglion; the tissue location to which the stimulation pulse is applied is selected from at least one of the following: ophthalmic nerve, supraorbital nerve, infraorbital nerve, nasociliary nerve, supratrochlear nerve, mental nerve, and auriculotemporal nerve.

9. An implantable electrical stimulation system, characterized in that, The system includes: Pulse generator; and An electrode assembly (1) that is electrically connected to a pulse generator includes a stress-relieving section (7) for buffering stress transmitted from the tail end of the electrode assembly (1) and at least one contact, wherein the at least one contact is configured to be placed in a first region of the patient's trigeminal nerve, wherein the stress-relieving section (7) remains vertical when there is a guidewire in the electrode assembly (1) and transforms into a ring-shaped curved structure after the guidewire in the electrode assembly (1) is removed; The annular bending structure of the stress relief section (7) consists of at least two rings to buffer the stress transmitted from the tail end of the electrode assembly (1) when the patient moves, and to prevent the electrode assembly (1) from shifting and falling out. The stress relief section (7) is located at the foramen ovale of the patient after it is transformed into an annular bending structure. The stress relief section (7) increases the travel distance of the electrode assembly (1) in the foramen ovale of the patient.

10. An electrode assembly (1), characterized in that, The electrode assembly (1) is made of silicone or other non-corrosive soft matrix as the main structure material and has a hollow guide wire. The electrode assembly (1) includes a stimulation section (2) and a stress relief section (7). The stress relief section (7) remains vertical when the guide wire is inside, and transforms into a ring-shaped curved structure after the guide wire is removed. The ring-shaped curved structure consists of at least two rings to buffer the stress transmitted from the tail end of the electrode assembly (1) when the patient moves, prevent the electrode assembly (1) from shifting and falling out, and increase the travel distance of the electrode assembly (1) in the patient's foramen ovale.

11. The electrode assembly (1) as claimed in claim 10, characterized in that, The annular curved structure consists of at least two rings to buffer the stress transmitted from the patient’s mouth movements and to increase the travel distance of the electrode assembly (1) within the patient’s foramen ovale.

12. The electrode assembly (1) as claimed in claim 10, characterized in that, The front end of the electrode assembly (1) is designed as a stimulation section (2) with contact points, and the rear end of the electrode assembly (1) is designed as a stress relief section (7). The connection between the stimulation section (2) and the stress relief section (7) is pre-bent.

13. The electrode assembly (1) as claimed in claim 10, characterized in that, The electrode assembly (1) is also provided with a metal positioning mark at its tail end, so as to facilitate the positioning and determination of the stress relief segment (7) after the guidewire is withdrawn by intraoperative X-ray fluoroscopy; the position can be located at the base of the skull from the internal opening of the foramen ovale to the semilunar ganglion.

14. An implantable electrical stimulation system, characterized in that, The device includes an electrode assembly (1) as described in any one of claims 10 to 13, the electrode assembly (1) being electrically connected to a pulse generator, wherein the pulse generator includes a power supply, a pulse generation circuit powered by the power supply, and an instruction generator for generating operating instructions; the pulse generation circuit generates stimulation pulses in a manner that at least partially generates operating instructions for controlling the pulse generation circuit by receiving a specified electrical stimulation scheme from the instruction generator.

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