RU169012U1 - Electrode for electrical stimulation of the optic nerve and optic pathways and control of physiological parameters of the orbital structures of the eye - Google Patents

Abstract

The utility model relates to medicine, namely to ophthalmology, neurology, neurosurgery, maxillofacial surgery, physiotherapy, and can be used to treat diseases and dystrophic processes in the optic pathways, eyeball and optic nerve. The developed electrode for electrostimulation of the optic nerve and optic pathways and control of the physiological parameters of the orbital structures provides constant safe targeted electrostimulation of the optic nerve and optic pathways. An electrode comprising: a polymer base made with the possibility of its placement along the lower wall of the orbit from the anterior orbital edge to the apex of the orbit, and the contacts located therein for transmitting electrical stimulating signals to the eyeball, optic nerve, visual pathways and taking physiological parameters. Moreover, the contacts are made with the possibility of connecting to the control unit of the electric generator and are combined into two groups, one of which is located closer to the distal end of the polymer base and is made with the possibility of predominant impact on the optic nerve and visual pathways, the other to the proximal end and is made with the possibility of preferential impact on the back pole of the eyeball. The width of the polymer base decreases from the proximal to the distal end.

Description

The utility model relates to medicine, namely to ophthalmology, neurology, neurosurgery, maxillofacial surgery, physiotherapy, and can be used to treat diseases and dystrophic processes in the optic pathways, eyeball and optic nerve.

Due to various reasons, a variety of processes can be observed in patients, the result of which is atrophy of the optic nerve, and this in turn causes irreversible blindness due to the fact that the electrical impulses do not reach or reach the cortical centers in an altered form and not at the right speed. The principle of electrostimulation of the optic nerve by percutaneous stimulation or implantation of special electrodes to the optic nerve is widely known in order to improve the conductivity of pulses, which will expand the patient’s field of view and / or improve visual functions.

Atrophy of the optic nerve (AZN) remains at the moment one of the main causes of progressive decrease in vision. This condition is the result of various consequences of pathological processes that capture the visual path in its various departments.

Currently, electrical stimulation of the optic nerve is carried out either projection or by bringing the source of exposure directly to the optic nerve.

A known electrode implantable in an orbit (RU 2238063, Linnik L.F. et al., 20.10.2004), which is a cannula electrode made of a metal spiral, coated with elastic electrical insulation and equipped with a hollow metal tip. During puncture implantation, a mandrel with a holder is inserted into the electrode, which is rigidly connected to the tip of the electrode. The implantation of the electrode is performed puncture through the skin of the eyelid in the lower outer third of the orbit. After implantation of the electrode, the mandrin is removed, a plug made of elastic sealed material is put on the hollow metal tip of the electrode, and the electrode is hemmed to the skin. By piercing the plug with a syringe needle (insulin syringe), the drugs are infused. Then, an external electric stimulator with a negative potential is connected to the electrode, and a positive potential is connected to an indifferent electrode placed in the patient’s hand, and electrophoresis is carried out with the introduced drugs and direct electrical stimulation of the optic nerve. At the same time, the implantation area is affected by a rotating magnetic field.

A device for continuous electrical stimulation of the optical nerve (JP 2008161230 A, 2008-07-17), which constantly delivers electrical stimulation to the optic nerve fibers for a long period of time, is known. The device includes a plurality of electrode parts for placement in a part of the optic nerve disk of a patient’s eye and means for generating a stimulating pulse signal for generating electric stimulating pulse signals output from the electrode parts. The electrode part has a needle electrode at the distal end and locking means to prevent the electrode part from falling out of a predetermined position that is at a predetermined distance from the distal end of the electrode, the distal end of the electrode being implanted into the part of the optic nerve head.

A device for continuous electrical stimulation of the optical nerve (CN 201127791 (Y) - 2008-10-08), related to implantable electrical stimulating electrodes for electrical stimulation of the optic nerve. The front end of the electrode rod is provided with an electrode contact terminal; the rear end of the electrode rod is connected to the electrode terminal; the diameter of the electrode rod is 1-3 mm, and the diameter of the electrode contact terminal is 2-30 mm; the electrode contact terminal has a circular shape, oval shape, ring shape or spherical shape; The contact stimulating surface is flat, concave or convex. The diameter of the electrode contact terminal is 3-30 mm larger than the diameter of the electrode rod; externally, the electrode contact terminal looks large, and the electrode rod looks externally small; The rod of the electrode of the electrode head is connected to the electrode terminal in the handle as a unit. With the exception of the stimulating surface, both the surface of the electrode rod and the surface of the electrode contact terminal are coated with an insulating paste forming an insulation layer. The electrode rod is designed with a bend of 5-90 degrees. A medical implantable electrode for stimulating an optical nerve can carry out a direct pulsed electrical stimulating effect on the optic nerve.

There is a method of treating partial atrophy of the optic nerve, including its electrical stimulation with biopolar impulses by means of a microwire electrode enclosed in a sheath, whereby the juxtabulbar segment of the nerve is stimulated, two electrodes are used in the sheath of the hemostatic collagen sponge, which are located diametrically opposite at the exit of the optic nerve from the eyeball ( RF patent No. 2032393, 04/10/1995).

A known method of electrical stimulation in patients with partial atrophy of the optic nerve after surgery for tumors of the chiasmosellar region, including preliminary diagnosis of the threshold of electrical sensitivity and electrolability of the patient, which set the amplitude of the treatment current and the pulse rate; conducting a series of packs of rectangular pulses carried out through an electrode placed on the eyelids (RF patent No. 2545411, 03/23/15).

A known method (RF patent No. 2189800, 09/27/02), according to which conduct electrical stimulation of the exit points of the branches of the trigeminal nerve on both sides with an exponential current with a pulse duration of 500 ms with a frequency of 1 Hz, a current amplitude of 0.5-5 mA before the occurrence of phosphenes and for 1 min at each point after their occurrence, for a course of treatment of 5-10 procedures daily.

There is a method of treating optic atrophy (RF patent No. 2025114, 02.11.89), according to which one electrode is implanted on the posterior pole of the eye, with the conductor through the conjunctiva, and the other fixed in the occipital region of the head. The impact is carried out by a bipolar pulsed current with a force of 10-100 μA, a frequency of 0.1-1.0 Hz, duration up to 150 ms for 10-15 minutes, course up to 10 sessions.

However, implantation of the electrode on the eyeball is quite traumatic with the threat of perforation of the eyeball, incisions in the bulbar conjunctiva can cause profuse bleeding and subsequent scarring, and there remains a high risk of developing infectious complications. With transdermal methods of electrical stimulation, it is necessary to use increased power parameters due to the dielectric characteristics of the intact skin and the sufficient distance of the optic nerve from the source of exposure.

In addition, when implanting the electrodes directly to the eyeball and optic nerve, there is a constant danger of damage, since the patient’s eyeball is in motion day and night, and the distal end of the electrode (according to known solutions) is not fixed, it may spontaneously shift in the tissues of the orbit and prolapse, the threat of developing infectious complications due to lack of tightness remains.

The task to be solved in this utility model was the development of an electrode that allows constant safe targeted electrostimulation of the optic nerve and optic pathways.

Achievable technical result is the implementation of continuous safe targeted electrical stimulation of the optic nerve and optic pathways.

The specified result is achieved due to:

- The developed configuration of the shape of the electrode is congruent to the bottom wall of the orbit. This shape of the electrode and the location of the contact groups most closely matches the projection of the optic nerve and the position of the eyeball. This, in turn, provides a position of the electrode (polymer base) and groups of contacts that will not change depending on the movements of the eyeballs, the position of the head and body in space.

- The used group of elements (one of which is closer to the distal end of the polymer base and made with the possibility of affecting the optic nerve, the other to the proximal end and is made with the possibility of affecting the posterior pole of the eyeball) is due to the tasks of addressing safe stimulation of the posterior segment of the eyeball and the course of the optic nerve and optic pathways - so that it is possible to sequentially or in a different order stimulate and amplify electrical impulses passing along the optic woo. The location of the sensor elements is associated with the ability to perceive electrical impulses from the optic nerve outside the visual load and process the received signals.

- Measurement of physiological parameters allows you to constantly monitor the declared position and, if necessary (in case of a threat to the safety of exposure), quickly change the treatment regimen,

- The presence of at least 4 contacts in each group is due to the fact that safe targeted, but sufficient in strength, area and depth stimulation of the posterior pole of the eyeball, optic nerve and optic pathways is carried out.

An electrode has been developed for electrostimulation of the optic nerve and optic pathways and for monitoring the physiological parameters of orbital structures, including

a polymer base made with the possibility of its placement along the lower wall of the orbit from the front orbital edge to the top of the orbit,

the contacts located in it for transmitting electrical stimulating signals to the eyeball, optic nerve, optic pathways and taking physiological parameters,

the contacts are made with the possibility of connecting to the control unit of the electric generator and are combined into two groups, one of which is located closer to the distal end of the polymer base and is made with the possibility of predominant impact on the optic nerve and visual paths, the other to the proximal end and is made with the possibility of predominant impact on back pole of the eyeball,

the width of the polymer base decreases from the proximal to the distal end.

Measured physiological parameters are at least one of: intraorbital pressure, pulse wave, orbital tissue pH, extracellular fluid osmolarity, glucose level, magnesium level, potassium level, chlorine level, sodium level, calcium level, phosphorus level, urea level, creatinine level , temperature of orbital tissues, speed of nerve impulses, nerve action potential, bioelectric potentials.

At least one of: pressure sensor, temperature sensor, pH sensor, nanosensor is used as contacts for taking physiological parameters.

In special cases, the implementation of the developed electrode may include the following features of its implementation:

- in the group of contacts located closer to the distal end of the polymer base, the elements are arranged in parallel;

- in the group of contacts located closer to the proximal end of the polymer base, the elements are arranged in parallel;

- the polymer base is made in the form of a plate having a shape close to triangular;

- the polymer base is made in the form of a plate having a shape close to trapezoidal;

- the polymer base is made in the form of a plate having a shape close to oval with a smaller radius of curvature from the side of the distal end and large from the side of the proximal end;

- the polymer base is made of material: silicone, porous polyethylene, polytetrafluoroethylene, teflon, polyvinylpyrrolidone, polyoxymethyl methacrylate, polymethyl methacrylate;

- the polymer base has overall dimensions: length from 10 mm to 41 mm, width from 10 mm to 42 mm, thickness - from 0.3 mm to 2.0 mm;

- the texture of the polymer base is heterogeneous;

- the texture of the polymer base is homogeneous;

- the polymer base is made transparent;

- the polymer base is made opaque;

- the surface of the polymer base is smooth;

- the surface of the polymer base is rough;

- the surface of the polymer base is porous;

- the surface of the polymer base with burrs;

- surface of the polymer base with notches;

- the surface of the polymer base is ribbed;

- the polymer base is made of hydrophilic material;

- part of the proximal end of the polymer base, on which the contacts are not located, has a texture different from the rest of the polymer base;

- the polymer base is made rigid;

- the polymer base is elastic;

- the polymer base is made congruent to the relief of the lower wall of the orbit;

- marking cut-off lines of the polymer base are applied to the surface of the polymer base.

The above particular cases of execution of the developed electrode also provide targeted safe stimulation, as follows:

- The heterogeneity of the structure can be used in difficult implantation conditions - the presence of rough scars and adhesions. This will allow more reliable fixation of the electrode to tissues, and therefore, to carry out safe stimulation.

- In uncomplicated cases - the physiological state of the orbit wall and the absence of deficiency of the soft tissues of the orbit - an electrode with a soft polymer base can be used to provide safe targeted stimulation. In case of post-traumatic deformities, defects of the lower orbit wall and soft tissue prolapse in the maxillary sinus - it is necessary to use a rigid polymer base of the electrode - to maintain the eyeball and soft tissues of the orbit after their reposition in the physiological position, which in itself will help to prevent the development of descending optic atrophy .

One possible electrode configuration is illustrated in FIG. 1, where:

1 - distal part of the polymer base

2 - proximal part of the polymer base

3 - electric cable

4 - contact group

5 - marking lines

The method of using the developed electrode for continuous electrical stimulation of the optic nerve and optic pathways and monitoring the physiological parameters of the orbital structures involves performing transconjunctival or subciliary access to the lower edge of the orbit. Then, in a blunt and sharp way, the tissues are extended to the front edge of the orbit, the periosteum is dissected, the periosteum is peeled deep into the orbit along the entire width of the lower wall of the orbit in the area of the projection of the optic nerve, and the developed electrode is placed along the lower wall of the orbit from the front orbital edge to the top of the orbit. Under visual control, the electrode is fixed to the periosteum and / or bone and the edges of the wound are sutured. The edges of the wound are fixed with interrupted sutures in layers. A fixing bandage is installed on the orbit.

It should be noted that two groups of contacts are connected to the control unit of the generator with an electric cable. The electrode cable can be brought out, for example, through the lateral orbital edge under the soft tissues or through a preformed bone perforation hole under the soft tissues of the temporal region or in front of the auricle. Next, the cable is connected to the control unit of the generator.

After installing the devices produce electrical stimulation.

Studies were conducted that clearly confirmed the stability of the position of the implantable electrodes in orbit. So, 12 subjects took part in the study, for whom a developed electrode was implanted for a long period. All subjects during this period led a usual way of life. The data of multispiral computed tomography (MSCT) performed immediately after implantation (on day 3) after 1 month and 3 months are presented in table 1.

As follows from table 1, only one subject of research according to MSCT, the installed electrode has shifted 3 days after implantation. This was due to an error in the surgical technique and insufficient fixation of the plate to the surrounding tissues with absorbable sutures.

One patient had a displacement of the installed electrode down 0.9 mm due to insufficient fixation of the distal end of the electrode. An electrode was installed for this patient in the presence of residual post-traumatic deformation of the lower wall of the orbit, not only as a permanent stimulator of the optic nerve, but also for additional support to the eyeball and soft tissues of the orbit in order to correct hypophthalmus. Repeated examination of this patient confirmed the presence of displacement of the installed electrode without additional dislocation in the structures of the orbit.

The remaining 9 subjects performed MSCT on the 3rd day, after 1 month and 3 months confirmed the absence of a fact of a change in the position of the implanted electrode.

Claims (30)

1. An electrode for electrical stimulation of the optic nerve and optic pathways and control of physiological parameters of the orbital structures of the eye, including a polymer base made with the possibility of its placement along the lower wall of the orbit from the front orbital edge to the top of the orbit, the contacts located in it for transmitting electrical stimulating signals to the eyeball, optic nerve, optic pathways and taking physiological parameters, the contacts are made with the possibility of connecting to the control unit of the electric generator and are combined into two groups, one of which is located closer to the distal end of the polymer base and is made with the possibility of predominant impact on the optic nerve and visual paths, the other to the proximal end and is made with the possibility of predominant impact on back pole of the eyeball, the width of the polymer base decreases from the proximal to the distal end. 2. The electrode according to claim 1, characterized in that the measured physiological parameters are at least one of: intraorbital pressure, pulse wave, orbital tissue pH, extracellular fluid osmolarity, glucose level, magnesium level, potassium level, chlorine level, sodium level , calcium level, phosphorus level, urea level, creatinine level, orbital tissue temperature, speed of nerve impulses, nerve action potential, bioelectric potentials. 3. The electrode according to paragraphs. 1-2, characterized in that as contacts for removing physiological parameters, at least one of: a pressure sensor, a temperature sensor, a pH sensor, a nanosensor is used. 4. The electrode according to claim 1, characterized in that in the group of contacts located closer to the distal end of the polymer base, the elements are arranged in parallel. 5. The electrode according to claim 1, characterized in that in the group of contacts located closer to the proximal end of the polymer base, the elements are arranged in parallel. 6. The electrode according to claim 1, characterized in that the polymer base is made in the form of a plate having a shape close to triangular. 7. The electrode according to claim 1, characterized in that the polymer base is made in the form of a plate having a shape close to trapezoidal. 8. The electrode according to claim 1, characterized in that the polymer base is made in the form of a plate having a shape close to oval with a smaller radius of curvature from the side of the distal end and large from the side of the proximal end. 9. The electrode according to claim 1, characterized in that the polymer base is made of material: silicone, porous polyethylene, polytetrafluoroethylene, teflon, polyvinylpyrrolidone, polyoxymethyl methacrylate, polymethyl methacrylate. 10. The electrode according to claim 1, characterized in that the polymer base has overall dimensions: length from 10 mm to 41 mm, width from 10 mm to 42 mm, thickness - from 0.3 mm to 2.0 mm. 11. The electrode according to claim 1, characterized in that the texture of the polymer base is heterogeneous. 12. The electrode according to claim 1, characterized in that the texture of the polymer base is homogeneous. 13. The electrode according to claim 1, characterized in that the polymer base is made transparent. 14. The electrode according to claim 1, characterized in that the polymer base is made opaque. 15. The electrode according to claim 1, characterized in that the surface of the polymer base is smooth. 16. The electrode according to claim 1, characterized in that the surface of the polymer base is rough. 17. The electrode according to claim 1, characterized in that the surface of the polymer base is porous. 18. The electrode according to claim 1, characterized in that the surface of the polymer base with burrs. 19. The electrode according to claim 1, characterized in that the surface of the polymer base with notches. 20. The electrode according to claim 1, characterized in that the surface of the polymer base is ribbed. 21. The electrode according to claim 1, characterized in that the polymer base is made of a hydrophilic material. 22. The electrode according to claim 1, characterized in that the part of the proximal end of the polymer base, on which the contacts are not located, has a texture different from the rest of the polymer base. 23. The electrode according to claim 1, characterized in that the polymer base is rigid. 24. The electrode according to claim 1, characterized in that the polymer base is made elastic. 25. The electrode according to claim 1, characterized in that the polymer base is made congruent to the relief of the lower wall of the orbit. 26. The electrode according to claim 1, characterized in that marking lines for cutting off the polymer base are applied to the surface of the polymer base.

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