Coil holding unit and transcranial magnetic stimulation device

Abstract

In order to provide a therapeutic coil unit capable of accurately and reliably attaching a therapeutic coil of repetitive transcranial magnetic stimulation (rTMS) to a treatment site, and a transcranial magnetic stimulation device having the same, a coil holding unit (20) is provided with: a frame member having a window part (14) enabling observation of a magnetic stimulation site for attaching a coil device for transcranial magnetic stimulation; and an indicator (6) indicating the center position of the magnetic field when the coil device is attached.

Description

Coil holding unit and transcranial magnetic stimulation device

[0001] The present invention relates to magnetic stimulation, and more particularly to a treatment coil holding unit for a magnetic stimulation device that allows a therapist to easily align and fix a treatment coil used in a magnetic stimulation treatment device to a treatment site on the head.

[0002] In recent years, interest has been growing in transcranial magnetic stimulation therapy as a treatment for neurological disorders such as intractable neuropathic pain for which drug treatment is not always effective, Parkinson's disease, Parkinson's syndrome, psychiatric disorders such as depression and PTSD, and rehabilitation after stroke. Repetitive transcranial magnetic stimulation therapy (rTMS) has been shown to be effective for patients who do not respond to treatment with various antidepressants such as tricyclics, MAOIs, and SARIs, and was approved for insurance coverage in Japan in 2019, making it a promising new treatment method.

[0003] rTMS is a non-invasive treatment that induces eddy currents using a pulsed magnetic field to stimulate cortical neurons, thereby altering cortical and subcortical activity. The eddy currents generated in the cortex stimulate neurons, releasing neurotransmitters, and repeated, regular stimulation can improve symptoms of depression.

[0004] High-frequency rTMS is administered to the left dorsolateral prefrontal cortex of the brain to treat depression. While rTMS treatment rarely causes serious side effects such as seizures, it can cause scalp pain, headaches, and discomfort during treatment. The occurrence of discomfort depends on accurate and repeatable coil placement in the appropriate position on the patient's head. During rTMS treatment, a physician and / or technician determines the required magnetic field strength and the precise location of the stimulation coil on the patient's head. However, subsequent treatments require accurate coil placement in the determined location.

[0005] WO2004 / 080526 (Special Publication No. 2006-520671) WO2007 / 123147

[0006] Transcranial magnetic stimulation (TMS) is used for the non-invasive treatment of psychiatric and neurological disorders. During treatment, aligning the center of the coil (the center of the generated magnetic field) with the treatment location is effective for both effectiveness and minimizing the impact on non-treatment areas. Furthermore, to maximize the therapeutic effect of magnetic stimulation, it is necessary to place the treatment coil as close to the treatment area as possible. This is because the electric field weakens as the treatment coil moves further away from the treatment area.

[0007] Patent Literature 1 discloses a device for positioning a treatment coil in a predetermined position, which includes a mounting frame member with a window for attaching the coil and an adjustment mechanism for positioning the coil in a desired position for each patient. To position the coil for each patient, this device includes a resin fixing means molded to fit the contours of the patient's head. However, the mounting frame must be adjusted and constructed for each patient, which requires time before treatment can begin. Furthermore, the bridge of the nose is used as the starting point for positioning, which creates the problem of prone to errors in the treatment position.

[0008] Patent Document 2 discloses a head fixation device for transcranial magnetic stimulation therapy, which includes a resin shell molded to fit the shape of the subject's head. This fixation device requires a custom-made shell to fit the shape of the subject's nose and ears, which requires time before treatment can begin. Furthermore, this fixation device employs a relative positioning method, using the bridge of the nose as the starting point for positioning, which tends to result in errors in the treatment position.

[0009] In conventional transcranial magnetic therapy using a treatment coil and treatment coil holder, a holder that fits the subject's head shape, such as the bridge of the nose or the shape of the ears, is used to easily align the treatment position with the center of the coil. Because the treatment position is estimated from an indirect positional relationship based on the subject's head shape, it is difficult to ensure the exact position of the treatment point due to the individual head shape and size of each patient, and it is difficult to minimize the misalignment between the treatment position and the treatment coil. While providing a dedicated holder for each patient would solve the above issues, this would require custom-made holders for each patient, which would increase costs.

[0010] Furthermore, although it is possible to ensure accurate positioning by using cameras and 3D positioning systems, which are well-known technologies, this requires devices and systems for positioning, resulting in a high-cost device configuration and creating a barrier to introducing the equipment.

[0011] The present invention provides the following therapeutic coil unit and transcranial magnetic stimulation device equipped with the same, which are devices that enable accurate and reliable attachment of rTMS therapeutic coils to treatment sites.

[0012] 1) A coil holding unit that holds a coil device that generates a magnetic field for magnetically stimulating a user in a predetermined position, the coil holding unit comprising: a coil mounting portion for mounting and fixing the coil device; a frame member having a window through which the magnetic stimulation site can be observed; and an indicator that shows the center position of the magnetic field when the coil device is mounted in the window of the frame member, and magnetic stimulation is performed at the predetermined position by aligning the indicator with the treatment site marked on the user's skin. 2) The coil holding unit described in 1), characterized in that the indicator is a fibrous or tape-like member stretched between the frame members that form the window, and comes into contact with at least the treatment site on the head when the coil device is mounted on the coil holding unit. 3) The coil holding unit described in 1), characterized in that the frame member and the indicator are non-magnetic members. 4) The coil holding unit described in 1), characterized in that the frame member covers the user's head and has a window through which at least the area including the dorsolateral prefrontal cortex of the user's head can be observed. 5) The coil holding unit described in 1) above, characterized in that it is provided with a fixing means for fixing the coil holding unit at the chin and back of the head of the user with the indicator and the treatment area aligned in a predetermined position. 6) The coil holding unit described in 1) above, characterized in that the coil holding unit is provided with at least two protrusions for attaching the coil device in a predetermined position. 7) The coil holding unit described in 1) above, characterized in that the frame member covers the user's head, is attached to the front side of the frame member along the user's midline, and is provided with a guide bar that determines the position of the frame member and the tip of the patient's nose. 8) The coil holding unit described in 7) above, characterized in that the tip of the guide bar is provided with an indicator that indicates the position of the tip of the user's nose.9) A transcranial magnetic stimulation device comprising a coil device that generates a magnetic field that magnetically stimulates the user's head, and a coil holding unit that holds the coil device in a predetermined position on the head, the coil holding unit comprising a coil mounting portion for mounting the coil device on the head, a frame member having a window through which the magnetic stimulation portion can be observed, a display device that shows the center position of the magnetic field when the coil device is mounted in the window, and a fixture that fixes the coil holding unit by aligning the display device with the marked treatment site. 10) The transcranial magnetic stimulation device described in 9) above, characterized in that the frame member covers the user's head, is attached to the front side of the frame member along the user's midline, and is provided with a guide bar that defines the position of the frame member and the tip of the patient's nose.

[0013] When applying a treatment coil of a transcranial magnetic stimulation device to a treatment site on a patient, it is difficult to confirm whether the center of the treatment coil's magnetic field is accurately aligned with the treatment site. The transcranial magnetic stimulation device of the present invention is equipped with a treatment coil holding unit that fixes the treatment coil so that the treatment position on the patient's head and the center of the treatment coil's magnetic field are aligned. By visually aligning an indicator provided on the treatment coil holding unit with the treatment site on the patient's head, the center of the treatment coil's magnetic field can be accurately positioned at the treatment site. Furthermore, the treatment coil can be easily and flexibly aligned and fixed to different treatment sites for various diseases, preventing magnetic stimulation of the wrong site during treatment.

[0014] In addition, by providing a guide bar on the front side of the frame member of the coil holding unit that determines the position relative to the patient's nasal tip along the patient's midline, the patient can align the coil holding unit themselves while looking in a mirror, after it has been aligned at a medical institution, etc., opening the way for transcranial magnetic therapy to be performed at home.

[0015] FIG. 1 is a schematic diagram of a conventional transcranial magnetic stimulation device. FIG. 2 is an external view of a first embodiment of the coil holding unit of the present invention. FIG. 3 is an external view of a coil device. FIG. 4 is a schematic diagram showing a method of wearing a transcranial magnetic stimulation device including the coil holding unit and coil device of the present invention. FIG. 5 is an external view of a second embodiment of the coil holding unit of the present invention. FIG. 6 is an external view of a third embodiment of the coil holding unit of the present invention. FIG. 7 is an external view showing a wearing state of the third embodiment of the coil holding unit of the present invention. FIG. 8 is an external view showing an incorrect wearing state of the third embodiment of the coil holding unit of the present invention.

[0016] The transcranial magnetic stimulation device and treatment coil holding unit of the present invention will be described using a treatment device for patients exhibiting depressive symptoms as an example. As shown in Figure 1, the transcranial magnetic stimulation device generates a pulsed magnetic field in the coil device 2 by supplying a pulsed current from a coil drive power supply 1 via a cable 3. By varying this magnetic field, weak eddy currents are locally induced according to Faraday's law, stimulating neurons in the brain. The stimulation site on the head must be accurately determined, and the coil device 2 is fixed with a treatment coil fixing base 10 to prevent it from shifting position during treatment, allowing magnetic therapy to be continued while the patient is seated in a chair.

[0017] Various parts of the brain control emotions such as joy, anger, sadness, and happiness, as well as sleep and appetite. In patients with depression, activity in the dorsolateral prefrontal cortex (DLPFC) on the left side of the brain is reduced, and the amygdala shows excessive activity. rTMS activates the DLPFC with magnetic stimulation, allowing motivation and thinking to function normally and secondarily suppressing the excessive response of the amygdala.

[0018] To perform rTMS treatment, it is necessary to find the appropriate stimulation site and intensity. The location of the DLPFC is the F3 point in EEG measurements, and the stimulation site and appropriate stimulation intensity are determined based on the BeamF3 method. The BeamF3 method measures three head values ​​and identifies the F3 location based on a predetermined algorithm. By identifying and marking the F3 point at the start of treatment, magnetic field irradiation is performed at the marked location without the need for prior positioning during subsequent treatments.

[0019] It is preferable to mark the head directly with permanent paint such as oil-based marker or ink. However, marking directly on the head has the disadvantages that the marking position is difficult to see due to hair, and the marking gradually disappears when washing the scalp in the shower, etc.

[0020] Therefore, during treatment, a cap that fits the head, such as a swimming cap, is worn and markings can be made on the cap. If a mesh or stretchy material like a swimming cap is used, the marking position may shift each time the cap is worn, so it is preferable to use a cap made of a less stretchy material such as cotton.

[0021] The cap is worn during treatment and removed after treatment, so patients must wear it in the same way every time. The cap worn during rTMS treatment has a line in the center of the cap that corresponds to the midline. By aligning this line with the nose line on the user's face, which corresponds to the midline, and by aligning the bottom line of the cap horizontally with the user's eyebrow line, the cap can be worn in the same position every time.

[0022] [Coil Holding Unit] Figure 2 shows an external view of a first embodiment of the coil holding unit of the present invention. The coil holding unit 20 holds a coil device, which generates a magnetic field to magnetically stimulate the patient's head, in a predetermined position on the head. The coil device is attached and magnetic stimulation is directly applied to the head. A coil fixing cap 4, equipped with a frame member having a window 14 through which the magnetic stimulation site can be observed, is placed on the head and secured to the head by a fastening band 5. The fastening band 5 may employ a dial-type ratchet band 11 or the like, allowing the size of the coil holding unit to be adjusted according to the user's head size and the degree of tightness to be adjusted. To reduce coil displacement during treatment, a securing means such as a chin strap may be further provided to secure the coil to the patient's chin, if necessary.

[0023] The window 14 is provided with a treatment position indicator 6, which is an indicator that shows the center position of the magnetic field when the coil device is attached. Magnetic stimulation can be applied to a predetermined position by visually aligning the treatment position indicator 6 with the marked treatment area. The treatment position indicator 6 is a fibrous or tape-like member that is stretched between the frame members that make up the window 14 and has a ring in the center to indicate the center position of the coil. However, the treatment position indicator 6 does not need to have a specific shape as long as the center position of the coil can be indicated by a change in shape or color other than a ring. To prevent magnetic field attenuation or shifting of the center position of the magnetic field due to a space being created between the coil device and the head when the coil device is attached, it is preferable to use a material such as elastic rubber so that the surface of the coil device, together with the treatment position indicator 6, is pressed against and makes contact with the head.

[0024] 5 shows a second embodiment of the treatment position indicator, in which two tape-shaped members 6' are arranged to cross each other. The intersection of the two tapes is set at the center of the coil, allowing for alignment with the treatment position.

[0025] The coil holding unit is used to attach the coil device and generate a magnetic field for treatment, so the frame members and treatment position indicators, in particular, are made of non-magnetic materials such as resin and fiber to avoid affecting the magnetic field. Because they are strong enough to hold the coil device and come into contact with the living body, biocompatible materials are preferred, and resin materials such as polylactic acid, polypropylene, and polyacetal are often used. If metal parts are required for joints, titanium is preferred.

[0026] Figure 3 shows an external view of the coil device 2. This view is from the scalp contact surface side, and an excitation coil is built into the housing. The excitation coil can be selected appropriately depending on the application, such as a normal circular coil, a figure-of-eight coil, or a butterfly-type coil with a modified coil angle. Figure 3 shows an example with a built-in figure-of-eight coil, and the coil center 7 indicates the center position of the magnetic field generated by the excitation coil of the coil device 2. When attached to the coil holding unit, the position of the coil center 7 coincides with the position of the ring part of the treatment position indicator 6.

[0027] When the coil device 2 is attached to the coil holding unit, the treatment position indicator 6 is pressed by the coil device 2 and comes into contact with the treatment area on the head. It is preferable that the treatment coil holding unit has a structure that does not cause interference with the magnetic field in the area where the coil device 2 is attached, and has a structure that allows the coil device to be in close contact with the treatment area.

[0028] The coil holding unit has at least two protrusions 9 for mounting the coil device in a predetermined position. These protrusions 9 can be fitted into recesses 12, 13 of the coil device to fix and hold both in a predetermined position. In this embodiment, the coil holding unit has protrusions and the coil device has recesses as fitting portions, but the combination of protrusions and recesses and the shape of the fitting portions can be selected as appropriate.

[0029] Figure 4 shows a method for attaching a transcranial magnetic stimulation device equipped with a coil holding unit and coil device of the present invention. When performing magnetic therapy, as shown in (4a), the doctor identifies the magnetic treatment location during the initial consultation and marks the treatment position on the patient's head. In the case of depression treatment, irradiation is performed on the DLPFC, which is located at the F3 point of EEG measurement, and the stimulation site is determined based on the BeamF3 method. A low-stretch cotton cap is placed on the patient, and markings are made on it.

[0030] Next, as shown in (4b), the coil holding unit of the present invention is placed over the head, and as shown in (4c), the treatment position indicator 6 is aligned with the marking position and the coil holding unit is fixed to the head. Then, as shown in (4d), the coil device is attached to the coil holding unit and treatment begins. As a depression treatment device, the coil holding unit must have a window that allows the patient's dorsolateral prefrontal cortex to be seen.

[0031] FIG. 6 shows an external view of a third embodiment of the coil holding unit of the present invention. This embodiment is a coil holding unit 20 of the first embodiment shown in FIG. 2 , in which the coil fixing cap 4 of the coil holding unit 20 is fitted to the frame portion 4' facing the user, covering the outer periphery of the head. The frame portion 4' is fitted with a guide bar 21, the tip of which corresponds to the nasal tip and is aligned along the patient's midline. After the coil holding unit 20 is positioned at a medical institution or other facility so that the treatment position 8 and the treatment position indicator 6 are aligned, the guide bar 21 is fixed to the frame portion 4'. The frame portion 4' and the guide bar 21 can be completely fixed together using adhesive or fusion bonding, or other methods can be used to indicate the fixed position. The tip of the guide bar 21 is provided with a ring-shaped indicator 22 that indicates the tip of the user's nose. The shape of the indicator 22 is not particularly limited; any shape can be used as long as it serves as a marker for the position of the nasal tip.

[0032] As shown in Figure 7, the user can attach the coil holding unit while looking in a mirror so that the guide bar 21 is straight along the user's midline and the indicator 22 at the end of the guide bar is positioned at the tip of the nose, thereby maintaining the position of the treatment position indicator 6 on the coil holding unit in alignment with the marked treatment area, and by fixing it in this state, the user can attach the coil of the transcranial magnetic stimulation device in the correct position.

[0033] As shown in Figure 8, the user can check for vertical misalignment (8a, 8b), horizontal misalignment (8c, 8d), and diagonal misalignment (8e, 8f) of the coil holding unit by looking in a mirror and adjust it to the correct wearing position as shown in Figure 7, making it possible to perform treatment at home in addition to treatment at a medical institution.

[0034] With this device, there is no need to reconfirm the treatment position, and in addition to the method of attaching the coil of the transcranial magnetic stimulation device after attaching the coil holding unit, it is possible to align the transcranial magnetic stimulation device with the coil already attached to the coil holding unit.

[0035] The present invention is a coil holding unit that holds a coil device used in transcranial magnetic stimulation therapy in a predetermined position, and can be used as a transcranial magnetic stimulation device.

[0036] REFERENCE SIGNS LIST 1 Coil drive power supply 2 Coil device 3 Cable 4, 4' Coil fixing cap 5 Tightening band 6, 6' Treatment position indicator 7 Coil center 8 Treatment position 9 Protrusion 10 Treatment coil fixing base 11 Dial type ratchet band 12 Recess 13 Recess 14 Window 20 Coil holding unit 21 Guide bar 22 Indicator

Claims

1. A coil holding unit that holds in a predetermined position a coil device that generates a magnetic field to provide magnetic stimulation to a user, the coil holding unit comprising a coil mounting portion for mounting and fixing the coil device, a frame member having a window through which the magnetic stimulation area can be observed, and an indicator that shows the center position of the magnetic field when the coil device is mounted in the window of the frame member, and magnetic stimulation is provided to the predetermined position by aligning the position of the indicator with the marked treatment area.

2. The coil holding unit as described in claim 1, characterized in that the indicator is a fibrous or tape-like member stretched between the frame members constituting the window portion, and comes into contact with at least the treatment area when the coil device is attached to the coil holding unit.

3. The coil holding unit according to claim 1, wherein the frame member and the display device are non-magnetic members.

4. A coil holding unit as described in claim 1, characterized in that the frame member covers the user's head and has a window portion through which at least the area including the dorsolateral prefrontal cortex of the user's head can be observed.

5. A coil holding unit as described in claim 1, further comprising fixing means for fixing the coil holding unit to the chin and back of the head of the user with the indicator and the treatment area aligned in a predetermined position.

6. The coil holding unit according to claim 1, wherein said coil mounting portion has at least two fitting portions for mounting and fixing the coil device to the coil holding unit.

7. A coil holding unit as described in claim 1, characterized in that the frame member covers the user's head, is attached to the front side of the frame member along the user's midline, and is provided with a guide bar that determines the position of the frame member and the tip of the user's nose.

8. A coil holding unit as claimed in claim 7, characterized in that the tip of said guide bar is provided with an indicator for indicating the position of the tip of the user's nose.

9. A transcranial magnetic stimulation device comprising a coil device that generates a magnetic field that provides magnetic stimulation to the user's head, and a coil holding unit that holds the coil device in a predetermined position on the head, the coil holding unit comprising a coil mounting portion for attaching the coil device to the head, a frame member having a window portion through which the magnetic stimulation portion can be observed, an indicator that shows the center position of the magnetic field when the coil device is attached to the window portion, and a fixing device that fixes the coil holding unit by aligning the indicator with the marked treatment area.

10. A transcranial magnetic stimulation device as described in claim 9, characterized in that the frame member covers the user's head, is attached to the front side of the user along the user's midline, and is provided with a guide bar that determines the position of the frame member relative to the tip of the user's nose.

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