JP2017000414A - Device and method for applying electric stimulus to retina - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric stimulation device and method which are low in invasiveness to a patient, and are free from a risk of a corneal problem in applying an electric stimulus to retina.SOLUTION: A device for applying an electric stimulus to retina includes skin electrodes consisting of an electrode for a right eye, an electrode for a left eye, and a common electrode, and is configured so as to pass an electric current between the electrode for a right eye and the common electrode, and apply an electric stimulus to the retina of the right eye, and pass an electric current between the electrode for a left eye and the common electrode, and apply an electric stimulus to the retina of the left eye. A method for applying an electric stimulus to the retina performed by the device equipped with the skin electrodes consisting of the electrode for a right eye, the electrode for a left eye, and the common electrode includes a step for passing an electric current between the electrode for a right eye and the common electrode, and applying an electric stimulus to the retina of the right eye, and a step for passing an electric current between the electrode for a left eye and the common electrode, and applying an electric stimulus to the retina of the left eye.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an apparatus and method for applying electrical stimulation to the retina. More specifically, the present invention relates to an apparatus and method for improving electrical function by applying electrical stimulation to the retina of a patient with retinitis pigmentosa or optic neuropathy.

Retinitis pigmentosa (RP) has been designated as a research project for specific diseases in 1995. It begins with night blindness and peripheral visual field impairment due to degeneration of retinal photoreceptors, especially rod cells, and gradually causes progressive visual loss. It is a slowly progressive genetic disease. As it progresses, the pyramidal cells of the photoreceptor cells are denatured and the visual acuity is reduced, and eventually it is blind. It is very important to maintain visual function in this disease that is progressive and leads to blindness. Currently, various clinical studies on the development of therapies are being conducted in various countries around the world. There is no. It is generally binocular, and there is no difference in the progression of the disease except for atypical cases.
Non-arteritic ischemic optic neuropathy (NAION) is a optic nerve circulatory disorder that develops rapidly in older people with diabetes and hypertension, and is one of the main causes of blindness in the elderly. Many of them develop severe visual impairment after onset. There is a report that the percentage of those whose visual acuity is less than 0.1 in the second half of the onset of NAION patients over 50 years old is 36%, and the recovery of visual function after the second half of the onset has been reported is very low . Currently, treatments include oral administration of corticosteroids, oral administration of platelet aggregation inhibitors such as aspirin, and intravenous administration of prostaglandin E preparations, all of which have low evidence levels and are effective against NAION Treatment has not been established yet. Simultaneous onset of both eyes is also observed, and the incidence of both eyes in the case of onset of one eye is very high at 15 to 25% within 5 years.

  In recent years, a group of Osaka University has found that a certain electrical stimulation has a neuroprotective effect on retinal ganglion cells by basic research, and it is a stimulation device that can be clinically applied to humans afterwards. Transcorneal electrode stimulation (TES) has been developed. TES is a method in which a contact lens type electrode for electroretinogram (ERG) measurement is placed on the cornea, and electrical stimulation is applied through this electrode from an electrical stimulator, and has been studied mainly for neuroprotective effects against optic nerve diseases. . The mechanism is that IGF-1 (Insulin-like-growth factor-1), which is one of neurotrophic factors, is produced from Muller cells by electrical stimulation, the concentration of IGF-1 increases in the retina, and the retinal ganglion Although it is said to act neuroprotectively on cells, it has not yet been fully elucidated. Later, in rat and rabbit RP animal models, it was reported that they also act neuroprotectively on retinal photoreceptors, and clinical studies targeting RP patients have been conducted overseas. Yes, it has not been fully verified.

JP 2003-210513 A JP 2011-45672 A

Fujimon, “Development of a new visual function evaluation system for ophthalmic examination diagnosis”, Japan Ophthalmological Society, December 10, 2004, Vol. 108, No. 12, p.809-830

  Since conventional TES performs electrical stimulation by placing electrodes on the cornea, the danger of corneal damage due to electrical stimulation has been pointed out. In addition, since the contact lens type electrode is installed on the cornea, it is a burden on the patient, and in particular for a long period of electrical stimulation. Furthermore, the production, storage and hygiene management of contact lens type electrodes is time consuming and expensive.

  Accordingly, it is desirable to provide an electrical stimulation apparatus and method that is minimally invasive to the patient and free from the risk of corneal injury when applying electrical stimulation to the retina.

It would also be desirable to provide a low cost electrical stimulation device and method that does not require effort in the manufacture, storage and hygiene management of the electrodes.
In addition, the conventional TES (see Patent Documents 1 and 2) is a device that is not suitable for treating both eyes because it treats by placing electrodes on only one eye. As described above, retinal pigment degeneration is generally binocular, and optic neuropathy often occurs simultaneously in both eyes. For this reason, the apparatus which can perform the treatment of both eyes easily is calculated | required. However, in the conventional TES, there is only one electrode for installing the cornea, and after treatment of one eye, it must be reattached to the other eye for treatment. The patient burden will increase.
Therefore, it would be desirable to provide an electrode stimulation apparatus and method suitable for treating both eyes simultaneously.

  According to one aspect of the present invention, an apparatus for applying electrical stimulation to a retina includes a skin electrode including a right-eye electrode, a left-eye electrode, and a common electrode, and the right-eye electrode. Current flows between the electrode and the common electrode to give electrical stimulation to the right eye retina, and current flows between the left eye electrode and the common electrode to give electrical stimulation to the left eye retina. It is structured.

  Further, according to one aspect of the present invention, the apparatus is configured to pass current at different timings between the right-eye electrode and the common electrode and between the left-eye electrode and the common electrode. It is characterized by that.

  Further, according to one aspect of the present invention, the apparatus is configured to pass different set currents between the right-eye electrode and the common electrode and between the left-eye electrode and the common electrode. It is characterized by that.

  Further, according to one aspect of the present invention, the apparatus causes pulsed currents of different widths to flow between the right-eye electrode and the common electrode and between the left-eye electrode and the common electrode. It is characterized by being configured.

  Further, according to one aspect of the present invention, the apparatus is configured such that each of the right-eye electrode, the left-eye electrode, and the common electrode includes a scissors, and a current flows through the scissors. Features.

  In addition, according to one aspect of the present invention, a method for applying electrical stimulation to the retina performed by a device including a skin electrode including a right eye electrode, a left eye electrode, and a common electrode. Applying a current between the right eye electrode and the common electrode to apply electrical stimulation to the right eye retina; and passing a current between the left eye electrode and the common electrode to the left eye Applying electrical stimulation to the retina.

  According to another aspect of the present invention, the method is characterized in that the step of applying electrical stimulation to the right eye retina and the step of applying electrical stimulation to the left eye retina are performed at different timings.

  According to another aspect of the present invention, the method is characterized in that the step of applying electrical stimulation to the retina of the right eye and the step of applying electrical stimulation to the retina of the left eye are performed with different set currents. To do.

  According to another aspect of the present invention, the method includes applying the electrical stimulus to the retina of the right eye and applying the electrical stimulus to the retina of the left eye with pulsed currents having different widths. Features.

  According to another aspect of the present invention, there is provided a method in which the electrode for the right eye, the electrode for the left eye, and the common electrode are each provided with an eyelid, and an electrical stimulus is applied to the retina of the right eye. The step of applying electrical stimulation to the retina is performed through the eyelids.

FIG. 1 is a view showing a patient wearing a conventional contact lens type electrode. FIG. 2 is a view showing a patient wearing a skin electrode according to an embodiment of the present invention. FIG. 3 is a view showing a patient wearing a skin electrode according to an embodiment of the present invention. FIG. 4 is a diagram illustrating a patient wearing a skin electrode according to an embodiment of the present invention. FIG. 5 is a diagram illustrating the timing of pulses for applying bipolar electrical stimulation to the retina of one eye according to an embodiment of the present invention. FIG. 6 is a diagram showing an operation diagram of retinal electrical stimulation treatment according to an embodiment of the present invention. FIG. 7 is a diagram illustrating the timing of pulses for applying bipolar electrical stimulation to the retina of both eyes according to an embodiment of the present invention. FIG. 8 is a diagram illustrating the timing of pulses for applying bipolar electrical stimulation to the retina of both eyes according to an embodiment of the present invention. FIG. 9 is a diagram illustrating the timing of pulses for applying bipolar electrical stimulation to the retina of both eyes according to an embodiment of the present invention.

  FIG. 1 is a diagram showing a patient wearing a contact lens type electrode 10 in the right eye. The contact lens type electrode 10 includes a pair of two electrodes arranged in a ring shape on a contact lens type base, that is, an inner electrode 11 and an outer electrode 12. And it is comprised so that an electrical stimulus can be given to a retina by applying a voltage between these two electrodes. In conventional transcorneal electrode stimulation (TES), after applying eye drop anesthesia to a patient, a corneal protective agent is applied and the contact lens electrode 10 is attached. Then, electrical stimulation was applied to the retina by applying electrical stimulation on the cornea via the cord 13 to the attached contact lens type electrode.

  The risk of corneal damage has been pointed out in such electrical stimulation of the cornea by conventional TES. In addition, in order to install a contact lens type electrode on the cornea, it is necessary to perform eye drop anesthesia or to apply a corneal protective agent, which is a burden on the patient, especially for a long-time electrical stimulation. . In addition, even if a contact lens type electrode is attached, since the electrode is attached with a cord, if the patient moves, the contact lens type electrode is detached and the electrical stimulation treatment is interrupted. Furthermore, the production, storage and hygiene management of contact lens type electrodes is time consuming and expensive.

  FIG. 2 shows a patient wearing the skin electrode 20 according to the present invention. As shown in the figure, the skin electrode 20 is attached to the skin around the eye, and includes a right-eye electrode 21, a left-eye electrode 22, and a common electrode 23. In FIG. 2, the electrodes 21 and 22 for the right eye and the left eye are respectively arranged under the eyes and the common electrode 23 is arranged on the forehead. It doesn't matter. For example, as shown in FIG. 3, the electrodes 21 and 22 for the right eye and the left eye may be disposed on the eye, and the common electrode 23 may be disposed on the nose. In FIG. 3, the electrodes are pasted on the eyebrows, but since the adhesion is not so good on the eyebrows, the electrodes may be pasted while avoiding the eyebrows.

  Alternatively, as shown in FIG. 4, the electrodes 21 and 22 for the right eye and the left eye may be disposed on the side of the eye, and the common electrode 23 may be disposed between the left and right eyes. In this case, in order to effectively apply electrical stimulation to the retina, the line connecting the electrode 21 for the right eye and the common electrode 23 is arranged so as to cross the cornea of the right eye. The line connecting the electrode 22 and the common electrode 23 is preferably arranged so as to cross the cornea of the left eye.

  As in the case of the contact lens type electrode 10, a pair of two skin electrodes (a total of four skin electrodes) may be used for the right eye and the left eye, respectively. That is, instead of the common electrode 23, a pair of two right-eye electrodes are respectively arranged above and below or right and left of the right eye, or a pair of two left-eye electrodes are respectively above and below or left and right of the left eye. It is also possible to arrange them. However, the number of electrodes can be reduced by using the common electrode 23.

  Each skin electrode has a size of about 25 × 45 mm, uses a nonwoven fabric as a base material, and secures adhesion to the skin and conductivity with a conductive adhesive gel. However, the skin electrode may have any configuration as long as it can effectively apply electrical stimulation to the retina. For example, you may use the skin electrode which embedded the wrinkles about 1-2 mm in length in a base material. In that case, since electrical stimulation can be given through the heel stuck in the skin, the electrical stimulation can be given with the heel instead of the surface having high contact resistance. Thereby, it is possible to energize with less contact resistance when applying electrical stimulation to the retina. In addition, by pricking acupuncture points around the eyes, not only the effect of electrical stimulation on the retina, but also the effect of acupuncture treatment can be expected.

  After the skin electrode 20 is mounted, settings for electrical stimulation treatment are performed. First, when applying electrical stimulation to the retina through the skin electrode, it is necessary to set an appropriate current intensity. Specifically, the skin electrode 20 is attached to the patient and is shown in FIG. 5 between the electrode 21 for the right eye and the common electrode 23 or between the electrode 22 for the left eye and the common electrode 23. The current intensity is gradually increased while applying such pulse-like electrical stimulation. This is shown in FIG. That is, the setting is started at time point 1 in FIG. 6, and the current intensity of the pulse is gradually increased. When a certain intensity is reached (time point 2 in FIG. 6), the patient has a pseudo phantom around the visual field. This is reported to the therapist (time point 3 in FIG. 6). Thereafter, the current intensity is further increased, and when a certain intensity is reached (time point 4 in FIG. 6), the patient feels a pseudo-light sensation in the entire visual field. Records the intensity at that time (time point 5 in FIG. 6). The current intensity of the electrical stimulation that makes the pseudo-light sense feel varies from patient to patient. Since the pseudo light sensation occurs in response to electrical stimulation of ganglion cells and optic nerves in the retina, a value higher than the current intensity at which the pseudo light sensation is felt in the entire visual field may be set as the setting value A of the current stimulation treatment. Preferred (time 6 in FIG. 6). However, it is not always necessary to set the current intensity at which a pseudo light sensation is felt, and the current intensity at which the pseudo light sensation is not felt may be set depending on the type or degree of retinal disease of the patient.

  In the case of single-eye treatment, the bipolar electrical stimulation shown in FIG. 5 is applied between the electrode for the right eye or the left eye attached to the patient and the common electrode. More specifically, a positive electrical stimulus is applied to the right-eye or left-eye electrode at a current intensity of the set value A for 10 msec, followed by a negative electrical stimulus of 10 msec at the same current intensity of the set value A, and thereafter Pause electrical stimulation for 30 msec. One cycle of this electrical stimulation is 50 msec, and the frequency is 20 Hz. This electrical stimulation is continued for about 30 minutes per treatment. In FIG. 6, treatment is performed from time point 6 to time point 7, and thereafter, treatment is performed from time point 10 to time point 11 with a pause period from time point 8 to time point 9 for the convenience of the patient or therapist. The total treatment time from time point 6 to time point 7 and from time point 10 to time point 11 is about 30 minutes. In the case of using a skin electrode, the electrode can be easily attached and detached as compared with the contact lens type electrode, so that it is possible to easily put a rest period for convenience.

  FIG. 7 shows a stimulation pattern in the case of simultaneous treatment of both eyes. This stimulation pattern is the same as in the case of FIG. 5, but a pause of 5 msec is provided between the stimulation of the right eye and the stimulation of the left eye. Thereby, both eyes can be effectively treated simultaneously using the common electrode 23, and the treatment time can be halved compared with the case of treating one eye at a time. That is, when electrical stimulation is applied to the right eye and the left eye at the same time, current flows easily between the right and left eye electrodes 21 and 22 and the common electrode 23 (that is, the one with lower resistance). Current flows, and simultaneous treatment of both eyes cannot be performed properly.

  In the case of a contact lens type electrode, two contact lens type electrodes 10 must be prepared for the right eye and the left eye in order to simultaneously treat both eyes. This means that it costs twice as much for a costly contact lens type electrode. In addition, it is an additional burden on the patient to wear the contact lens electrode 10 on both eyes.

  Even if each eye has a different degree of disability, or even if the current intensity at which the pseudo-light sensation is felt is different, if the setting value of the current intensity for each eye can be set individually, both Simultaneous eye treatment is possible. FIG. 8 shows a case where the setting value B of the current intensity of the right eye is larger than the setting value A of the current intensity of the left eye.

  Furthermore, as shown in FIG. 9, the electrical stimulation pulse period can be shortened to 5 msec instead of 10 msec. It is preferable that the period of this pulse can be changed in consideration of the patient's symptoms and burden. For example, as shown in FIG. 9, the setting value of the current intensity may not be changed by the left and right eyes, but the pulse period may be changed by the left and right eyes.

  Moreover, although the treatment time by electrical stimulation is about 30 minutes, as shown in FIG. 6, taking a patient's symptom and burden into consideration, you may put a break on the way. Regarding the frequency of receiving treatment, it is preferable to perform treatment several times a month or periodically, confirm recovery of visual function, and observe the progress.

  The electrical stimulation apparatus and method of the present invention are not limited to NAION, and can be applied to optic nerve diseases in a broad sense. For example, there is no effective treatment for traumatic optic neuropathy and natural recovery must be awaited, but it is expected that recovery will be promoted by the electrical stimulation device and method of the present invention. Glaucoma is also included in the broad sense of optic neuropathy, and the effect of the electrical stimulation device and method of the present invention is expected. Furthermore, in retinal diseases, not only RP, but also the effect is expected for diseases that cause severe visual dysfunction due to progression of age-related macular degeneration, diabetic macular disease and the like.

DESCRIPTION OF SYMBOLS 10 Contact lens type electrode 11 Inner electrode 12 Outer electrode 13 Code 20 Skin electrode 21 Electrode for right eye 22 Electrode for left eye 23 Common electrode

Claims (10)

A device for applying electrical stimulation to the retina,
It has a skin electrode consisting of an electrode for the right eye, an electrode for the left eye, and a common electrode,
An electric current is applied between the right-eye electrode and the common electrode to apply electrical stimulation to the right-eye retina, and an electric current is applied to the left-eye retina from the left-eye electrode and the common electrode. An apparatus configured to provide a stimulus. The apparatus of claim 1, comprising:
An apparatus configured to allow current to flow between the right-eye electrode and the common electrode and between the left-eye electrode and the common electrode at different timings. The apparatus according to claim 1 or 2, comprising:
An apparatus configured to cause different currents to flow between the right-eye electrode and the common electrode and between the left-eye electrode and the common electrode. The device according to any one of claims 1 to 3,
An apparatus configured to pass pulsed currents having different widths between an electrode for the right eye and the common electrode and between the electrode for the left eye and the common electrode. An apparatus according to any one of claims 1 to 4,
The electrode for the right eye, the electrode for the left eye, and the common electrode each have a heel,
A device characterized in that it is configured to pass current through a gutter. A method for applying electrical stimulation to the retina performed by a device having a skin electrode composed of an electrode for the right eye, an electrode for the left eye, and a common electrode,
Applying an electrical stimulus to the retina of the right eye by passing a current between the electrode for the right eye and the common electrode;
Applying electrical current between the left eye electrode and the common electrode to apply electrical stimulation to the retina of the left eye. The method of claim 6, comprising:
The method of applying electrical stimulation to the retina of the right eye and applying electrical stimulation to the retina of the left eye are performed at different timings. The method according to claim 6 or 7, comprising:
A method in which the step of applying electrical stimulation to the retina of the right eye and the step of applying electrical stimulation to the retina of the left eye are performed with different set currents. A method according to any one of claims 6 to 8, comprising
A method in which the step of applying electrical stimulation to the retina of the right eye and the step of applying electrical stimulation to the retina of the left eye are performed with pulsed currents having different widths. A method according to any one of claims 6 to 9, comprising
The electrode for the right eye, the electrode for the left eye, and the common electrode each have a heel,
The method of applying electrical stimulation to the retina of the right eye and applying electrical stimulation to the retina of the left eye are performed through the eyelid.

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