U.S. patent application number 17/524344 was filed with the patent office on 2022-04-28 for magnetic device for treating living tissues.
This patent application is currently assigned to EPITECH MAG LTD.. The applicant listed for this patent is EPITECH MAG LTD.. Invention is credited to Tomer CARMELI, Ehud KATZNELSON, Itzik RONEN.
Application Number | 20220126109 17/524344 |
Document ID | / |
Family ID | |
Filed Date | 2022-04-28 |
View All Diagrams
United States Patent
Application |
20220126109 |
Kind Code |
A1 |
KATZNELSON; Ehud ; et
al. |
April 28, 2022 |
MAGNETIC DEVICE FOR TREATING LIVING TISSUES
Abstract
A device for treating living tissue with a magnetic field. The
device includes one or more coil applicators; and a generator
configured to drive a stimulation coil that is housed within the
coil applicator that faces a tissue being treated. The device
provides a magnetic field in a range of 0.1 T to 3 T at a distance
of 1 cm or less from the face of the coil applicator.
Inventors: |
KATZNELSON; Ehud; (Ramat
Yishay, IL) ; CARMELI; Tomer; (Alonei Abba, IL)
; RONEN; Itzik; (Nirit, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
EPITECH MAG LTD. |
Yokneam Illit |
|
IL |
|
|
Assignee: |
EPITECH MAG LTD.
Yokneam Illit
IL
|
Appl. No.: |
17/524344 |
Filed: |
November 11, 2021 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
16634009 |
Jan 24, 2020 |
11247065 |
|
|
PCT/IL2018/050831 |
Jul 26, 2018 |
|
|
|
17524344 |
|
|
|
|
International
Class: |
A61N 2/02 20060101
A61N002/02; H01F 5/04 20060101 H01F005/04; H01F 5/06 20060101
H01F005/06; A61N 2/00 20060101 A61N002/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 26, 2017 |
IL |
253677 |
Claims
1. A device for treating a living tissue with magnetic fields, the
device comprising: one or more coil applicators, each having a
face; and a generator configured to drive a stimulating coil that
is housed within the coil applicator, said stimulating coil being
configured to face a tissue to be treated, wherein the device is
configured to provide a magnetic field in a range of at least 0.1 T
to 3 T at a distance of 1 cm or less from the face of the one or
more coil applicators.
2. The device of claim 1, wherein each coil applicator comprises:
said stimulating coil, said stimulating coil including a core and
windings; a ferromagnetic reflector plate adjacent to the
stimulating coil, the ferromagnetic plate having a plane defining a
rear side and a front side of the stimulating coil, the front side
being configured to be oriented toward the tissue and the rear side
being configured to be oriented facing away from the tissue to be
treated; and a cooling mechanism configured to cool the stimulating
coil.
3. The device of claim 2, wherein the core is a ferromagnetic core
disposed within the stimulating coil and the ferromagnetic
reflector plate is adjacent to the stimulating coil and to the
core.
4. The device of claim 2, wherein the ferromagnetic reflector plate
comprises a groove for a lead/wire that electrically connects the
stimulating coil with circuitry.
5. The device of claim 1, further comprising an air flow shell with
openings, the shell enclosing the stimulating coil and configured
to enable air to flow around the stimulating coil, and to prevent
contact between the tissue and the stimulating coil.
6. The device of claim 2, wherein the cooling mechanism comprises a
heat sink and at least one cooling fan.
7. The device of claim 1, wherein the generator is configured to
generate magnetic pulses having an amplitude of up to about 3 T,
length of 50 to 2000 .mu.s, frequency up to 200 pulses/s, and a
rate of change of at least 1000 T/s.
8. The device of claim 2, wherein the core and the plate are
configured to form a ferromagnetic body that reflects the magnetic
field created in the stimulating coil towards the treated tissue,
thereby minimizing the energy losses and the cooling
requirements.
9. The device of claim 2, wherein the core and the ferromagnetic
reflector plate are made of reactive sintered iron.
10. The device of claim 6, wherein the heat sink comprises a flat,
heat-conductive portion adjacent to the ferromagnetic reflector
plate, the heat-conductive portion comprising a groove configured
to reduce eddy currents.
11. The device of claim 10, wherein the ferromagnetic reflector
plate comprises a flat ferromagnetic reflector plate, the flat
ferromagnetic plate being connected to the flat heat-conductive
portion of the heat sink in a heat-conductive interface.
12. The device of claim 1, further comprising an apparatus
configured to fix a position of the tissue at a distance from the
stimulating coil and a direction with respect to the stimulating
coil.
13. The device of claim 12, wherein the distance is 10 mm or
less.
14. The device of claim 1, having a shape in the form of
eyeglasses.
15. The device of claim 12, wherein the apparatus comprises a set
of joints, axes and levers thereby providing the device with
multiple degrees of freedom of movement.
16. The device of claim 1, further comprising one or more spacers
defining a distance between the stimulating coil and the tissue to
be treated.
17. The device of claim 16, wherein the one or more spacers
comprise an insulating layer having a thickness of 10 mm or
less.
18. The device of claim 16, wherein the one or more spacers
comprise an insulating layer having a thickness of 2 mm or
less.
19. The device of claim 12, wherein the apparatus comprising a
resting place configured to receive a human chin and/or
forehead.
20. The device of claim 1, wherein the device is configured to
provide a magnetic field in a range of 0.1 T to 5 T at a distance
of 1 cm or less from the coil applicator face.
21-24. (canceled)
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation application of
U.S. patent application Ser. No. 16/634,009, filed 24 Jan. 2020,
entitled "MAGNETIC DEVICE FOR TREATING LIVING TISSUES", which is a
National Phase application of PCT/IL2018/050831, filed 26 Jul.
2018, entitled "MAGNETIC DEVICE FOR TREATING LIVING TISSUES," which
claims priority from Israeli Patent Application No. 253677, filed
26 Jul. 2017, entitled "MAGNETIC DEVICE FOR TREATING LIVING
TISSUES", the disclosures of which are incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to treating biological
tissues, more particularly to a magnetic device for directing
energy to living tissues with high output and with improved
focusing mechanism.
BACKGROUND OF THE INVENTION
[0003] The effects of magnetic fields on animals have been employed
in various medical treatments (US 2010/0130945). An important
treatment target is epithelial tissue. Epithelial tissue surfaces
constitute a mechanical barrier against external harmful factors,
and although they belong to key components of the body's defense,
many details of their function remain unknown. For example, corneal
epithelium blocks the penetration of harmful substances, but also
polarized substances such as water and ions, into the anterior
chamber, and an impairment in the corneal barrier leads to pain,
chronic symptoms, injury, or even vision loss. US 2002/0035358
describes a method for treating corneal ulcers with electromagnetic
pulses. WO 2014/181327 describes a magnetic device for treating an
eye. U.S. Pat. No. 8,246,529 describes a method and a magnetic
device for treating neurological disorders. The device includes a
magnetic core made of a ferromagnetic powder.
[0004] The existing systems have several drawbacks. Some of the
published systems aim at employing relatively weak magnetic fields;
for example, US 2010/0130945 employs fields of nT to .mu.T
strength, and do not relate to the problems associated with
employing stronger fields or overcoming such problems.
[0005] Also, the known systems do not sufficiently address the
efficiency of the magnetic energy transfer to the treated tissue,
the losses that may result, for example, from low conversion of the
electrical energy; or from inefficiently directing the magnetic
energy flow. Furthermore, heat losses constitute a double problem:
low energy efficiency and overheating of the device parts. Such
overheating may lower the device lifetime or require expensive
and/or large heat dissipation means. Of course, all the mentioned
problems are interconnected and will be more prominent for stronger
magnetic fields.
[0006] It would be highly advantageous to have a system or method
that could enable treating living tissues with magnetic fields in a
broad range of the field intensities.
SUMMARY OF THE INVENTION
[0007] According to some embodiments, device for treating a living
tissue with magnetic fields is provided, the device including one
or more coil applicators; and a generator configured to drive a
stimulation coil that is housed within the coil applicator that
faces a tissue being treated, wherein the device is configured to
provide a magnetic field in a range of at least 0.1 T to 3 T at a
distance of 1 cm or less from the coil applicator(s) face.
[0008] In further embodiments, the coil applicator includes a
stimulating coil with a core and windings, a ferromagnetic
reflector plate adjacent to the stimulating coil, the ferromagnetic
plate having a plane defining a rear side and a front side of the
stimulating coil, the front side being oriented toward the tissue
and the rear side being oriented facing away from the tissue; and a
cooling mechanism configured to cool the stimulating coil.
[0009] In further embodiments, the core is a ferromagnetic core
disposed within the stimulating coil and the ferromagnetic plate is
adjacent to the stimulating coil and to the core. In further
embodiments, the ferromagnetic reflector plate includes a groove
for a lead/wire that electrically connects the coil with
circuitry.
[0010] In further embodiments, an air flow shell with openings is
provided, the shell enclosing the stimulating coil and configured
to enable air to flow around the coil and the plate, and to prevent
contact between the tissue and the coil.
[0011] In further embodiments, the cooling mechanism includes a
heat sink and cooling fan.
[0012] In further embodiments, the generator is configured to
generate magnetic pulses having an amplitude of up to about 3 T,
length of 50 to 2000 .mu.s, frequency up to 200 pulses/s, and a
rate of change of at least 1000 T/s.
[0013] In further embodiments, the core and the plate are
configured to form a ferromagnetic body that reflects the magnetic
field created in the coil towards the treated tissue, thereby
minimizing the energy losses and the cooling requirements. In
further embodiments, the core and the plate are made of reactive
sintered iron.
[0014] In further embodiments, the heat sink includes a flat,
heat-conductive portion adjacent to the ferromagnetic plate, the
heat-conductive portion including a groove configured to reduce
eddy currents.
[0015] In further embodiments, the ferromagnetic plate and the flat
heat-conductive portion are formed in a shape of two flat members
connected in a heat-conductive interface.
[0016] In further embodiments, an apparatus is provided that is
configured to fix the position of the tissue at a distance from the
coil and a direction with respect to the coil. In further
embodiments, the distance is 10 mm or less.
[0017] In further embodiments, the device has a shape in the form
of eyeglasses.
[0018] In further embodiments, the apparatus includes a set of
joints, axes and levers thereby providing the device with multiple
degrees of freedom of movement.
[0019] In further embodiments, the device includes one or more
spacers defining a distance between the coil and the treated
tissue. In further embodiments, the spacer includes an insulating
layer having a thickness of 10 mm or less. In further embodiments,
the spacer includes an insulating layer having a thickness of 2 mm
or less.
[0020] In further embodiments, the apparatus includes a resting
place for a human chin and/or forehead.
[0021] In further embodiments, the device is configured to provide
a magnetic field in a range of 0.1 T to 5 T at a distance of 1 cm
or less from the coil applicator face.
[0022] According to some embodiments, a method is provided for
treating a living tissue with magnetic fields in a wide range of
strength, including providing a tissue stimulating magnetic field
having an intensity of up to 5 T at a distance of 10 mm or less
from the tissue.
[0023] In further embodiments, the stimulating magnetic field is
applied to a tissue of a human organ, and the organ is afflicted
with a condition selected from the group consisting of: an eye
condition, including dry eye and mechanical ablation; a
neurological disorder; a condition associated with pathological
proliferation; and a pathology associated with epithelial
tissues.
[0024] In further embodiments, the magnetic field intensity
includes pulses having an amplitude of up to 5 T, a length of 50 to
2000 .mu.s, a frequency up to 200 pulses/s, and a rate of change of
at least 200 T/s. In further embodiments, the frequency is up to
1,000 T/s.
[0025] Embodiments of one aspect of the present invention provide a
device for treating a living tissue with magnetic fields in a wide
energy range, for example between 0.1 T and 3 T, including (i) a
stimulating coil for creating a magnetic field of from 0.1 T to 3 T
at a distance of about 1 cm from the coil; (ii) a low conductivity
ferromagnetic core, situated within the coil; (iii) a low
conductivity ferromagnetic plate, adjacent to the coil and in
contact with the core, the plane of the plate defining the front
side and the rear side of the stimulating coil, which radiates the
energy of the magnetic field and the electric field to the treated
tissue, in use the front side being oriented toward the treated
tissue and the rear side facing away from the eye. The plate
preferably includes a hole or groove for leads connecting the coil
on the front side with the energy source and/or the circuitry on
the rear side, (iv) cooling mechanism including a fan and a heat
sink; and (v) an air flow shell with openings, enclosing the
stimulating coil and the cooling means, enabling the air to flow
around or through the coil, the plate, and the heat sink, and
configured to prevent contact between the tissue and the coil. The
plate may be circular. The plate may form one solid block with the
core.
[0026] In some embodiments, the device includes one or more coils,
and a generator connected with the coil(s) configured to generate
magnetic pulses having an amplitude of up to 5 T, a length of 50 to
2000 .mu.s, a frequency of up to 200 pulses/s, and a rate of change
of at least 200 T/s. These magnetic pulses induce electric field
pulses in the tissue having an amplitude of up to 300 Volts per
meter.
[0027] In some embodiments, the core and the plate form a
ferromagnetic body focusing and reflecting the magnetic field
created in the coil towards the treated tissue, thereby minimizing
the energy losses and the cooling requirements. The core and the
plate are made of a maternal exhibiting low power losses at kHz
frequencies. In some embodiments, the materials include reactive
sintered iron.
[0028] In some embodiments, the device includes an efficient
cooling means including at least one fan and a heat sink. In some
embodiments, the heat sink includes a flat portion adjacent to the
ferromagnetic plate and is configured to prevent circular
electrical currents (eddy currents) in the plane of the plate, such
as at least one groove shaped to prevent the circular electrical
currents. The core and the reflector plate constitute a focusing
mechanism of the device, enabling a high output delivery of the
magnetic field energy in a desired direction into a biological
tissue.
[0029] In some embodiments, the device's heat sink includes a flat
heat-conductive portion adjacent to the ferromagnetic plate. In
some embodiments, the ferromagnetic plate and the flat portion have
a shape of two flat cylinders being connected in a heat-conductive
interface, for example a circular-shaped interface.
[0030] In some embodiments, the magnetic device includes an
apparatus for fixing the mutual position, including distance and
orientation, of the treated tissue and the coil. Predetermined
distance and direction of the tissue toward the coil, as well as
the magnetic signal strength and shape, is determined by the user,
in accordance with the desired treatment. The predetermined
distance is preferably 20 mm or less, for example 10 mm or less. In
some embodiments, the apparatus includes a set of joints, axes, and
levers that provide to the device several degrees of freedom of
movement and enable one to direct the magnetic field in a broad
range of intensities from desired distances and angles relative to
the treated tissue.
[0031] In some embodiments, the device is configured as a hand-held
instrument for easy handling by the user. In some embodiments, the
device includes spacers defining the distance from the treated
tissue to the coil radiating the energy of the magnetic field. The
spacers may have a thickness of 10 mm or less, such as 2 mm or
less. The spacers may also define the distance between the device
and the treated human subject; the distance may, in some
applications, be 5 mm or less, in some applications 4 mm or less,
in some applications 3 mm or less, in some applications 2 mm or
less, and in some applications 1 mm or less.
[0032] In some embodiments, the treated tissue is a part of a human
organ. In one embodiment, the tissue is a part of human eye. In one
embodiment of the invention, the device includes an apparatus for
fixing the position of the eye to be treated at predetermined
distance from the coil, the apparatus including a resting place for
a human chin and/or forehead. The device may have a shape of
goggles or eyeglasses, or other suitable wearable devices.
[0033] In some embodiments, the apparatus has a fixed position or
with a coarse adjustment mechanism, configured to allow the subject
to lean there-against and achieve as accurate eye orbit position
relative to the coil via an ergonomic interface.
[0034] Embodiments of another aspect of the present invention are
directed to a method of treating a living tissue with magnetic
fields in a wide range of strength, for example between 0.01 T and
5 T, such as 0.1 T to 3 T. The method includes creating a magnetic
field of a desired intensity, in pulses having an amplitude of up
to 5 T, a length of 50 to 2000 .mu.s, a frequency up to 200
pulses/s, and a rate of change of at least 200 T/s, preferably at
least 1000 T/s. Further, in some embodiments, the method may be
executed by one or more of the following steps and related
components i) positioning a nonconductive ferromagnetic core
situated within the coil ii) operating a ferromagnetic plate
(acting as a reflector), adjacent to the rear side of the
stimulating coil, which coil is oriented toward the treated tissue
with its front side; iii) operating cooling means including a fan
and a heat sink; and iv) operating an air flow shell with openings,
enclosing the stimulating coil, enabling the air to flow around or
through the coil and the sink and cool them, and preventing the
contact between the tissue and the coil. The sink preferably
includes a heat-conductive flat part adjacent to the ferromagnetic
plate, the part provided with at least one groove shaped to prevent
circular electrical currents (eddy currents) within the flat part,
for example one or more radial grooves, wherein both the plate and
the flat part are preferably shaped as flat cylinders.
[0035] In some embodiments, the device preferably treats tissues
which belongs to human organs, particularly organs afflicted with a
condition selected from the group consisting of eye diseases
including dry eye, neurological disorders, conditions associated
with pathological proliferation, and pathologies associated with
epithelial tissues.
[0036] In still further embodiments, the invention provides the use
of the described device in treating a disease in a human subject in
need of such treatment selected from the group consisting of eye
diseases, neurological disorders, conditions associated with
pathological proliferation, and pathologies associated with
epithelial tissues.
[0037] In some embodiments, the invention provides the use of the
magnetic device in treating epithelium-associated diseases. In a
preferred embodiment, the device is used in treating an eye, for
example in conditions including dry eye.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] The principles and operation of the system, apparatus, and
method according to the present invention may be better understood
with reference to the drawings, and the following description, it
being understood that these drawings are given for illustrative
purposes only and are not meant to be limiting, wherein.
[0039] FIGS. 1A and 1B are schematic depictions of the structure of
a magnetic device, in accordance with embodiments of the present
invention, wherein a generator is driving a stimulation coil that
is housed within a coil applicator that faces a tissue being
treated;
[0040] FIG. 2 shows the degrees of control over the position of the
coils relative to the eyes for case of treating eyes tissues,
according to some embodiments;
[0041] FIGS. 3A and 3B show a circular ferromagnetic plate in one
block with a core for a device of the invention, according to some
embodiments (FIG. 3A), and a circular ferromagnetic plate with a
hole/pass for the coil lead in the device of the invention,
according to some embodiments, and/or for attaching the heat sink
(FIG. 3B);
[0042] FIGS. 4A, 4B and 4C show stimulating coils, demonstrating a
reflector plate (FIG. 4A or 4C) that precludes protruding of the
lead/wire to a space between the stimulating coil and the treated
organ (FIG. 4B), according to some embodiments;
[0043] FIG. 5A shows a cross-section of the stimulating coil and
heat sink, which includes coil windings, ferromagnetic core and
reflector plate, and heat sink, wherein an example is shown of a
heat sink, core and reflector, attachable by a screw, according to
some embodiments;
[0044] FIG. 5B shows a cross-section of the stimulating coil and
heat sink, which includes coil windings, the ferromagnetic core and
reflector plate, and the heat sink, wherein the interface between
the coil and the heat sink reaches closer to the windings,
according to some embodiments;
[0045] FIG. 5C shows a reflector, core and heat sink, according to
some embodiments, attached together and separated;
[0046] FIG. 6A shows an example of a flat circular part of the heat
sink, which is attached to the ferromagnetic plate in contact with
the coil, and the direction of eddy current, according to some
embodiments;
[0047] FIG. 6B shows a flat circular part of the heat sink, where
grooving is used to diminish the eddy currents, according to some
embodiments;
[0048] FIG. 7 shows an air cooling mechanism of an embodiment of
the invention, where air openings are at the coil face and a fan is
located behind it, with a funnel that forces the air to go through
fins of the heat sink;
[0049] FIG. 8 shows an exemplary air cooling mechanism where the
air openings and fan are located at the coil's perimeter, according
to some embodiments;
[0050] FIG. 9 shows an exemplary air cooling mechanism, according
to some embodiments, including a heat pipe to transfer the heat
away from the coil to a heat sink, which is located away from the
tissue;
[0051] FIG. 10 shows an electric field ring around the eye ball or
orbit affecting a plurality of nerves around and in the orbit,
according to some embodiments;
[0052] FIG. 11 shows a cross section of exemplary coil windings and
treated tissue by induced electric field around the eye, also
showing the intensity of the electric field decays with distance
from the coil;
[0053] FIG. 12 shows an exemplary biphasic, sinusoidal, magnetic
field pulse as a function of time, according to some embodiments,
as well as an exemplary induced electric field of a cosine
shape;
[0054] FIG. 13 shows a cross section of a coil with windings of
copper conductor, according to some embodiments;
[0055] FIG. 14 shows clinical results of a corneal staining score
change from baseline for a treated and untreated eye, according to
some embodiments;
[0056] FIG. 15 shows the improvement in corneal condition
demonstrated by Fluorescein staining in a pre-treated cornea and 4
weeks after treatment for an example patient, according to some
embodiments;
[0057] FIG. 16 shows a conceptual example of a table-top apparatus
having a coil in proximity to a human patient's eye, when the
patient is leaning toward the apparatus, against an ergonomic
interface 163, according to some embodiments;
[0058] FIGS. 17A-17C show several configurations of a table top
apparatus, according to some embodiments, FIG. 17A showing a side
projection of the apparatus, FIG. 17B showing two coil applicators
for two eyes, and FIG. 17C showing a single coil applicator and
human subject turning his/her head to place the eye/orbit in front
of it;
[0059] FIG. 18 shows a human patient's face, with an ergonomic
patient specific interface; and
[0060] FIG. 19 shows a schematic electrical block diagram of the
device, according to some embodiments, including a generator
storage capacitor and stimulating coil.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0061] The following description is presented to enable one of
ordinary skill in the art to make and use the invention as provided
in the context of a particular application and its requirements.
Various modifications to the described embodiments will be apparent
to those with skill in the art, and the general principles defined
herein may be applied to other embodiments. Therefore, the present
invention is not intended to be limited to the particular
embodiments shown and described, but is to be accorded the widest
scope consistent with the principles and novel features herein
disclosed. In other instances, well-known methods, procedures, and
components have not been described in detail so as not to obscure
the present invention.
[0062] In some applications using the present invention, an
afflicted epithelial tissue is treated with relatively strong and
rapidly changing magnetic pulses, inducing electrical field in the
tissue.
[0063] In some embodiments, a device is configured to magnetically
treat animal or human tissues, and which creates a strong magnetic
field and efficiently transfers its magnetic field and electric
field energy, to the treated tissue.
[0064] In some embodiments, the device is configured to
magnetically treat animal or human tissues, and which efficiently
directs the active magnetic and electric field pulses into the
treated tissue.
[0065] In some embodiments, the device is configured so as to
exhibit relatively low overheating.
[0066] In some embodiments, the device is configured to treat
living tissues with magnetic and electric fields in a broad range
of the field intensities and treating regimens, and in some
embodiments the device is configured for safe and easy handling by
experienced practitioners.
[0067] As described below, and with reference to respective figures
below, a magnetic device 11 is provided with a coil having a core
32 producing a strong magnetic field, provided with an adjacent
ferromagnetic base or reflector plate 33 and with a configuration
to inhibit eddy currents and a suitable cooling mechanism as shown
in FIGS. 7-9, directs the magnetic pulses to a treated tissue with
surprising precision and energy efficiency. A device having the
coil 14 can be advantageously employed for treating an ocular
surface. A non-invasive magnetic stimulation device for the
treatment of epithelium by repetitive magnetic stimulation
according to the invention, for example for treating the corneal
epithelium in the case of dry eye syndrome, includes a magnetic
stimulator 16 driving one or more stimulating coils 14. The
magnetic stimulator 16 may employ two or more coils intermittently,
such as via two output connectors and appropriate control
logic.
[0068] FIGS. 1A and 1B schematically show the structure of a
magnetic device 11 according to some embodiments of the invention,
wherein the front side of a stimulation coil 21 faces a tissue to
be treated 12, with the coil 14 being disposed inside the shell 19,
the entire coil applicator 13 is positioned relative to the tissue
by apparatus 15, for example, object or mechanism for placing the
applicators in front of the tissue to be treated. As can been with
further reference to FIGS. 1A and 1B, the device 11 may include one
or more coil applicators 13, each of which may include: a
stimulating coil 14 and its driving wires 23, a cooling mechanism
including a fan 18, a heat sink 17, and an air flow shell 19 with
ventilation openings enclosing and insulating the above components
from the user's contact. The insulation allows the user to bring
the front side of the stimulating coil 21 to close proximity, such
as less than 1 cm, to the treated tissue 12, such as a tissue that
is a part of an organ requiring the treatment.
[0069] In the case of treating an ocular surface, for example for
the treatment of dry eye disease, it is beneficial to stimulate
afferent and efferent nerves passing through the foramina around
the eye (supraorbital, infraorbital, lacrimal, efferent branches of
the facial nerve, innervation of the Orbicularis and Riolan's
muscle, etc.). In order to stimulate these nerves, a direct
electrical stimulation by electrodes is sub-optimal since it will
require a large number of electrodes at various locations around
the eye. Instead, a magnetically induced electric field can
stimulate these nerves simultaneously without the need for any
contact. Such electric field should have a peak intensity of for
example 100 Volts/meter, at the target nerves, in order to be
effective. The intensity is highly dependent on factors such as
nerve morphology and alignment between electric field and nerve
directions.
[0070] In some embodiments, an electric field or activation ring
104 with a diameter of approximately 40 mm is optimal for targeting
these nerves in an efficient manner in typical adults, as can be
seen in FIG. 10, which shows the electric field ring 101 around the
eye ball or orbit 102 affecting a plurality of nerves around and in
the orbit. The diameter and width of the ring 101 can be changed to
fit different patient sizes, to target different nerve groups or
sub-groups and to reduce possible side effects such as tingling
sensations.
[0071] In some embodiments, different sizes of "activating
field(s)" may be provided, by using various coil sizes and
reflector sizes. For example, coil size may or may not be optimized
to include activation of the nerves inside the nose. In other
example, size may allow activating fewer or more nerves right
around the orbit of the eye to minimize side effects.
[0072] In some embodiments, the activation ring 104 is efficiently
attainable by an adequately designed magnetic coil that induces a
circular electric field in the tissue, which is maximal at
approximately 40 mm diameter and has an electric field intensity of
sufficient amplitude in a diameter of, for example, 20-60 mm or
15-55 mm or 30-50 mm.
[0073] In order to obtain such activation pattern, according to
some embodiments, a preferred choice is a circular coil that has an
average winding diameter of about 40 mm, and a minimal and maximal
winding diameter that are close to 40 mm, for example, a minimum
winding diameter of 30 mm and a maximum winding diameter of 50 mm.
Such a design also prevents exposure of ocular tissues such as
cornea or retina to high intensity electrical field, as seen in
FIG. 11, which shows a cross section of an example coil windings
111 and treated tissue 112 by an induced electric field 113-115
around the eye (cornea 116, retina 117). The intensity of the
electric field decays with distance from the coil. e.g. the field
has a high intensity. As can been in FIG. 11, the device may direct
the electric field to various positions proximal to the coil, such
that the closer to the coil, the stronger the field. The decay is
continuous as the distance from the coil grows, but as can be seen
in the shown example, position 113 has a strong field, position 114
has a weaker field, and position 115 has the weakest field, of
these three example positions.
[0074] It is beneficial for the magnetic stimulation device to have
a pulse duration of a few hundreds of microseconds, for example 300
microseconds. A typical magnetic stimulation device output magnetic
field pulse is a biphasic sine shape, as seen in FIG. 12, which
shows an exemplary biphasic, sinusoidal, magnetic field pulse 121
as a function of time. Also shown is an exemplary induced electric
field of a cosine shape 122. The duration of the pulses in FIG. 12
is 0.0003 seconds or 300 microseconds 123.
[0075] As can be further seen, also with reference to FIG. 19, the
device can be considered from an electrical circuit perspective, as
an RLC circuit 191, which includes an energy storage capacitor 192
with capacitance C, a coil 190 with inductance L, and a total
resistance R. Before the generation of the magnetic pulse, the
energy storage capacitor 192 is charged with a voltage Vc0. The
duration (or period) of the sine pulse is approximately T=2.pi.*
(L*C) when L is the inductance of the coil and C is the capacitance
of the energy storage capacitor. The induced electric field is
proportional to the time derivative of the magnetic field and
therefore has a pulse with the cosine shape 122, with the same
frequency or pulse duration. For example, if C=175 .mu.F (micro
Farad) and L=13 .mu.H (micro Henri) the resulting pulse duration,
or period, is approximately 300 microseconds 123. A similar pulse
duration can be obtained using a different selection of C and L,
providing that C*L is kept at approximately 2.3*10{circumflex over
( )}-9. Therefore, for example, if C=200 .mu.F, L should be 11.5
.mu.H. The frequency of the pulse in this case is approximately 3.3
Kilohertz. FIG. 12 is provided for conceptual illustration without
specific intensity values.
[0076] In some cases, a generator with an energy storage capacitor
of 175 .mu.F may be operated with one or more of the following
aforementioned design requirements. Average coil windings diameter
of approximately 40 mm; Coil winding diameter range of 30-50 mm;
Pulse duration of 300 microseconds; and Electric field peak value
of 100 V/m e.g. 15 mm from the coil face.
[0077] There are a number of design options for achieving these
requirements. For example, the option shown in FIG. 13, which shows
a cross section of a coil with 22 windings of copper conductor 130
with a minimum winding diameter 131 of approximately 13 mm and
maximum winding diameter 132 of approximately 23 mm. 133 shows the
coil's front side placed close to the tissue 134, according to some
embodiments. In order to obtain the above electric field
requirement, 15 mm from the coil face, an initial capacitor voltage
Vc0 is required to be approximately 1000 Volts, and the time
averaged ohmic loss for a single pulse is approximately 110
KiloWatt.
[0078] Alternative ways to increase the pulse duration without
increasing the number of coil windings could be to increase the
capacitor inductance or add another coil in series to the
stimulating coil. However, both of these alternatives are
sub-optimal in the energetic efficiency.
[0079] In a preferred embodiment of the invention, the stimulating
coil includes a ferromagnetic plate as a reflector that reflects
the magnetic field towards the treated organ in order to minimize
energy losses, minimize the cooling requirements, and make the coil
more efficient. Such a reflector is schematically shown in FIG. 3A,
which shows a circular ferromagnetic plate 30 in one block with a
core for a device of the invention, according to one embodiment
(FIG. 3A), and a circular ferromagnetic plate 30 with a hole/pass
34 for the coil lead in a device of the invention, according to an
embodiment, and/or for attaching the heat sink (FIG. 3B). As can be
seen, circular ferromagnetic plate 30 includes a core 32 on the
front side, focusing the magnetic field so that the magnetic field
passes more in the center of the coil (through the core). The core
32 also makes the stimulating coil production less sensitive to the
exact position of the coil windings. The core 32 and reflector
plate 33 increase the inductance of the coil and thereby increase
the duration of the pulse for the same number of windings and
windings geometry. For the same requirements as mentioned above,
the coil with circular ferromagnetic plate 30 and a core 32 on the
front side can be driven with an initial capacitor voltage Vc0 of
approximately 70 volts, and resulting with a time averaged ohmic
loss for a single pulse of approximately 50 Kilowatt. The reduction
in ohmic loss per pulse is very important when stimulating the
tissue at higher pulse rates than are typically used in brain
stimulation, for example higher than 20 pulses/sec.
[0080] When employing conventional ferromagnetic materials in
non-DC applications, the magnetic effects may be dramatically
reduced by the formation of eddy currents, which for example reduce
the time derivative of the magnetic field. The device according to
the invention employs electromagnetic coils provided with
ferromagnetic cores and ferromagnetic reflectors, which increases
energy efficiency and reduces also the cooling requirements. The
ferromagnetic material used for the ferromagnetic cores used in the
invention is preferably reactive sintered iron, for example,
mutually electrically insulated magnetic granules, for example such
as Permedyn.TM., in the state of a solid body (non-powdered).
Reactive sintered iron has low conductivity and a narrow hysteresis
loop, therefore providing low eddy current and low hysteresis loss
in frequencies up to 50 kHz.
[0081] An important property of the material for the coil and core
according to the invention is its power loss at magnetic field
changes in the kHz range. For example, if a pulse has a perfect
single sine period shape and duration of 300 microseconds, its
frequency will be 3.33 KHz. The pulse may differ from a perfect
sine, and the rate of changes of the magnetic field may include a
different range of frequencies. The materials suitable for the
cores in a device according to the invention may exhibit power
losses, for example, 150-750 W/kg at 0.5-1.0 T and 2-6 kHz, such as
200-400 V/kg. In some applications, the inventors observed that the
total heat generated in the core and reflector was about 1% of the
heat generated by the electrical current in the windings.
[0082] In some embodiments, the windings of the coil are typically
electrically insulated by a thin coating layer (not shown). The
windings are typically made of a wire of a fairly large
cross-section (a few square mm) to maintain low electrical
resistance and reduce the ohmic energy loss. A square cross section
is often preferred to obtain optimal wires and current density.
Alternatively, they can be in the form of a sheet (e.g. 0.5 mm
thick), or of a round cross-section. The coil windings may include
a combination of several types of windings in series, such as sheet
and square cross-section wire. The windings may be molded in a
thermally conductive epoxy encapsulation 57 or similar material in
order to absorb the mechanical strain/shock to the coil windings by
the electromagnetic pulses, and in order to improve the thermal
conduction. An epoxy encapsulation can withstand an operating
temperature of up to 130.degree. C. In some examples, as can be
seen with reference to FIG. 5, the core 51 and reflector plate 52
may have a thread 53 (FIG. 5A) for mounting of a heat sink 54 and a
hole/pass/groove 45 in the reflector plate 52 to allow passing of
the coil lead (wire) so that it does not protrude to the front side
of the coil 43 (see FIG. 3 and FIGS. 4A and 4C). This is important
because any protrusion of wires to that area would lead to a larger
distance between the stimulating coil face (front side 43) and the
treated organ 44.
[0083] FIGS. 4A-4C show a stimulating coil 40 demonstrating how the
pass in the plate 45 (FIG. 4A or 4C) precludes protruding of the
lead (wire) to the space between the stimulating coil 40 and the
treated organ or tissue (44), according to some embodiments FIG. 4B
shows such protrusion of a copper wire 42 out of the front side of
the coil 140 between the area between the treated tissue 44 and the
coil 40; this is avoided in embodiments shown in FIGS. 4A and 4C
having a wire pass/hole 45 in the reflector plate.
[0084] In some embodiments, the thread 53 can facilitate the
attachment of the heat sink 54 to the reflector plate 52, in some
embodiments, as shown in FIG. 5A, which shows a cross-section of an
assembly, which includes coil windings 55, ferromagnetic core 51,
reflector plate 52, and heat sink 54, wherein the heat sink is
attached to the plate or core by screw. In this case, the interface
between the reflector plate 52 and the heat sink 54 may include a
thermal paste 56 to provide for good heat transfer. The heat sink
54 may also be provided with a heat sink projection 59 and a male
protrusion(s) 58 inserted into slots in the reflector plate 52
and/or around the reflector plate, as shown in FIG. 5B, which shows
a cross-section of an assembly which includes coil windings, a
ferromagnetic core and the reflector plate and a heat sink, wherein
the interface between the coil and the heat sink reaches closer to
the windings. A further example of the reflector plate and heat
sink can be seen in FIG. 5C.
[0085] According to some embodiments, the heat sink has a
hole/pass/groove to facilitate the passage of the conductive wires
of the stimulating coil, in a similar fashion as the reflector
plate. Since the heat-conductive heat sink is usually made of
metals of high electrical conductivity such as aluminum or copper,
the magnetic field will induce circular eddy currents in its base,
as shown by the arrows 62 in FIG. 6A, which shows a flat circular
part of the heat sink 61 which is to be attached to the
ferromagnetic plate in contact with the coil, and the direction of
eddy current 62, according to some embodiments. This would lead to
generating heat within the heat sink. To prevent this, thin grooves
63 may be cut in the heat sink base according to some embodiments,
reducing the undesired eddy current effect. Grooves of various
shapes and directions may be employed, examples of which are shown
in FIG. 6B, which shows a flat circular part of the heat sink 61,
where grooves 63 diminish the eddy currents 62, according to some
embodiments.
[0086] In some embodiments, it is preferred to remove the heat both
through the heat sink and directly from the face of the epoxy or
from the coil windings, particularly when non-uniform generation of
heat in the windings occurs or when the reflector plate and the
core materials do not exhibit optimal thermal conductivity. In some
embodiments, an air cooling system is employed including air
clearances 75 in the coil applicator face (as schematically shown
in FIG. 7) to facilitate the flow of air on the coil epoxy
encapsulation 70, wherein a tunnel in the shape of a funnel 73
forces the air flow within the inner fins of the heat sink 72, the
air flow being mainly perpendicular to the face of the stimulating
coil.
[0087] In some embodiments, the air cooling system (FIG. 8)
includes an air flow mainly parallel to the face of the stimulating
coil 80 and through the heat sink 81. The heat sink fins 82 may
have a spike shape or preferably a plate shape to maximize their
surface area and to reduce air flow turbulence. The fan 83 either
pushes the air or preferably pulls the air, using cooling air
clearances 85.
[0088] In some embodiments, the air cooling may also include the
use of a heat pipe 90, for example, in order to transfer the heat
away from the coil 91 to the heat sink 92, for example as
schematically shown in FIG. 9. This arrangement may be used to
minimize the size of the part of the coil applicator that is put in
proximity to the target organ, or to incorporate a commercial
cooling module (heat sink with fan), including cooling fans 95.
[0089] The coil applicator 13 may include one or more sensors (not
shown) that measure the temperature within the coils flow shell 19
and convey the measurement to the magnetic stimulator 16 as a part
of a safety mechanism to prevent overheating in the case of a
failure in the cooling mechanism.
[0090] The device according to the invention enables management of
intensive heat formation in treatments with strong fields of IT or
more, when the coil currents may reach the values 1000 amperes or
more, and when employing large frequencies (even thousands of Hz).
Such conditions would otherwise overheat the device without
efficient cooling; moreover, the energy input would be too high
without the device's focusing mechanism (constituted by the core
and reflector plate), which increases the energy efficiency by
reducing the magnetic field outside the region of treatment.
[0091] In the case of treating ocular surface diseases, such as dry
eye, in some embodiments, two devices can be so as to treat both
eyes simultaneously. The device may include an apparatus (15) for
fixing the position of the patient's target organ, such as a chin
and forehead rest for fixing the position of the eye in the case of
an ocular application. The device may include an apparatus that is
used to control the position and the orientation of the coil
applicator(s) relative to the treated organ of the patient. The
apparatus allows for precise positioning of the stimulating coils
within close proximity to the organ so the net distance between the
face of the coil and the target organ is less than 1 cm, and in
some cases a minimal insulating layer of as low as 1 mm will serve
as a spacer. This apparatus can include a set of joints, axes and
levers, which provide several degrees of freedom of position
control.
[0092] FIG. 2 shows the degrees of control over the position of the
coil applicators relative to the eyes for case of treating eyes
tissues, according to some embodiments, for the case of ocular
treatment. The coil applicator can be handheld by a
user/operator/patient in proximity or adjacently to the target
organ, or spacers may be employed, such as a rubber ring. In case
of an ophthalmic device, an eyecup may be included, for example
such as used in binoculars. The coil applicator preferably has a
size and shape enabling placement adjacent to the treated organ,
for example within the eye orbit. The coil applicator may include a
visual mark on its frontal face, corresponding to the center of
stimulating coil, to facilitate accurate positioning in the center
of the eye visual field and orbit. In one embodiment, the device
includes a motorized table, such as often used for ophthalmic
procedures (for example for slit lamp bio-microscopy). The
motorized table can allow height adjustment of the position of the
device to allow seating the patient comfortably, both for the
patient and the examiner. After adjusting the height of the
ophthalmic table and chin rest, the coil applicators are placed
near the patient eyes to be treated. The placement of the coil
applicators adjacently to the eyes is achieved by setting the
height of the ophthalmic table according to the patient body size,
setting the chin rest height for a comfortable sitting position,
and adjusting the position and orientation of the coil applicators
relative to the eyes.
[0093] In accordance with some embodiments, the coil applicator is
configured or adjusted in a broad or coarse way, thereby leaving
the fine positioning for the human patient to perform. FIG. 16
illustrates a conceptual example of a table-top apparatus 161
having a stimulating coil 162 in proximity to the human patient's
eye, when the human patient is leaning toward the apparatus,
against some ergonomic interface 163, according to some
embodiments. As can be seen, the coil applicator(s) may be
positioned on a table top with an ergonomic interface 163 that
guides the patient to correctly position the eye or orbit in the
correct position relative to the stimulating coil 162. This can be
done using a material that can absorb the patient's head weight and
features such as foam rubber or silicone, shaped to fit typical
facial features around the orbit such as the shape of the bones
around the orbit, and the shape of the nasal bridge.
[0094] As can be seen in FIG. 16, the alignment of the
electromagnetic field around the eye's orbit and the innervation
just outside the orbit is an anatomical optimization that enables
consistent focusing on the same spot for each patient (+/-0.5 cm
tolerance max).
[0095] FIGS. 17A-17C show several configurations of a table top
apparatus, according to some embodiments. FIG. 17A shows a side
projection of the apparatus with height 171 and tilt 172 relative
to the table top 173 either fixed or controllable FIG. 17B shows
two coil applicators for two eyes, where the angles 174 may be
either fixed or controllable. FIG. 17C shows a single coil
applicator and human subject turning his/her head to place the
eye/orbit in front of the device. The apparatus may include control
over height and tilt (FIG. 17A) and/or turn (FIG. 17B). The
apparatus may have some suspension mechanism to which the coil is
harnessed, so that when contacted with the patient's face the coil
is forced to the accurate position and orientation relative to the
patient's orbit.
[0096] In another configuration, the ergonomic interface may be
made of a disposable material and replaced with a new one for every
treatment. In another configuration, the ergonomic disposable
interface may be fitted for each patient in a personalized manner,
such as creating an imprint of the facial structure of the patient
around the eye so it achieves accurate positioning relative to the
patient facial features such as the bones around the orbit, and
nasal bridge. Such ergonomic disposable interface may be made in a
similar manner to a radiotherapy mask, producing a form that may be
attachable to a coil applicator intended to provide and/or enhance
alignment and repeated re-alignment for the intent of
electromagnetic stimulation of peripheral nerve tissue in the
vicinity of the eye.
[0097] After the interface has been shaped according to the
patient's facial features, additional positioning may be required
of additional elements such as male snap connectors, relative to
the facial features, and these connectors will serve as an
interface to female snap connectors on the coil applicator, as
shown in FIG. 18. As can be seen, a human patient's face 181 may be
provided with ergonomic patient specific interface 182, which has
four connectors, such as male snap connectors 183, according to
some embodiments. Also shown is a coil applicator 184 with four
matching connectors such as female snap connectors 185.
[0098] In some embodiments, the facial attachment may form an
imprint from the face; in one example, similar to a plastic "mesh"
used for gamma knife radiation fixation etc. In a further example,
an impression may be made with "smooth on facial silicone" or in
other suitable ways.
[0099] In still further embodiments, the coil applicator may be
part of a table top apparatus or positioned using glasses or other
suitable wearable member, to help place the coil applicators of the
device opposite or proximal to a specific location(s). In some
cases, the wearable device may have customization to keep in proper
place, e.g. flexible material to form an optimized fit.
[0100] In some embodiments, the method includes forming an imprint
of a facial structure such as the area surrounding the eye or a
mammal, both eyes of a mammal, the eyes and the nose of a mammal or
the entire forehead and the eyes of a mammal, or the entire
forehead and face of a mammal to generate a form that may be
attachable to n coil applicator intended to provide and/or enhance
alignment and repeated re-alignment for the intent of
electromagnetic stimulation of peripheral nerve tissue in the
vicinity of the eye.
[0101] Embodiments of the present invention will be further
described and illustrated by the following examples.
[0102] In a first pilot study for testing the safety of repetitive
magnetic stimulation for the treatment of dry eye, the study was
registered with ClinicalTrials.gov Identifier No. NCT03012698 The
study was an Interventional study type and the treatment employed
repeated magnetic stimulation (RMS) treatment to the eye. The study
tested the safety of RMS for treating dry eye. Patients were asked
to undergo a one-time treatment with an EpiTech Corneal Magnetic
Stimulation Device, a device according to some embodiments of the
invention, on one eye. Changes were monitored for over a study
period of 3 months. The study included males and females, 18-80
years old, with moderate to severe dry eye syndrome, the estimated
enrollment was 30 patients. The data were processed in accordance
with the requirements of the International Committee of Medical
Journal Editors and the International Clinical Trials Registry
Platform (ICTRP) of the WHO. Of the first five (5) patients, three
(3) had Sjogren syndrome, one (1) had meibomian gland dysfunction
and one (1) had aqueous deficiency not related to Sjogren
syndrome.
[0103] All patients tested completed a three month follow up. The
reduction in corneal staining in the treated eye was significantly
larger than in the untreated eye within one week after treatment,
and appeared most prominent at eight weeks, as seen in FIG. 14. The
untreated eye also showed some non-significant reduction in
staining, suggesting there might be some treatment effect on the
contralateral eye. Average change and standard error are shown for
five patients at a follow-up at 1, 4, 8 and 12 weeks following
treatment to one eye, and further showing that the corneal staining
was graded according to the NEI/industry scoring on a scale of
0-15.
[0104] An example of the change in corneal staining is shown in
FIG. 15, which shows the improvement in corneal condition
demonstrated by Fluorescein staining score improvement in a
pre-treated cornea and four (4) weeks after treatment for an
exemplary patient from the five patients whose staining data was
shown in FIG. 14, using devices and methods as described
herein.
[0105] While the invention has been described using some specific
examples, many modifications and variations are possible. It is
therefore understood that the invention is not intended to be
limited in any way, other than by the scope of the appended
claims.
[0106] The foregoing description of the embodiments of the
invention has been presented for the purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed. It should be appreciated
by persons skilled in the art that many modifications, variations,
substitutions, changes, and equivalents are possible in light of
the above teaching. It is, therefore, to be understood that the
appended claims are intended to cover all such modifications and
changes as fall within the scope of the invention.
* * * * *