U.S. patent application number 16/525018 was filed with the patent office on 2020-01-23 for electrosurgical device.
The applicant listed for this patent is Tiumed LLC. Invention is credited to Scott T. Latterell.
Application Number | 20200022746 16/525018 |
Document ID | / |
Family ID | 39269253 |
Filed Date | 2020-01-23 |
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United States Patent
Application |
20200022746 |
Kind Code |
A1 |
Latterell; Scott T. |
January 23, 2020 |
ELECTROSURGICAL DEVICE
Abstract
An electrosurgical assembly is disclosed, the assembly having
two, three or more electrodes configured to provide advantageous
tissue removal and precision for conducting electrosurgical
procedures, including improved ablation and coagulation of tissue.
The electrodes are configured and arranged so that energy can be
applied in a highly uniform and precise fashion, depending upon the
application. In addition, the electrosurgical assembly allows
flexibility in use by, in some embodiments, allowing selective
switching of the active and return electrodes, and also selective
switching between ablation and coagulation modes. In certain
embodiments the invention includes one or more electrodes having
the ability to undergo changes in shape.
Inventors: |
Latterell; Scott T.;
(Minneapolis, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Tiumed LLC |
Minneapolis |
MN |
US |
|
|
Family ID: |
39269253 |
Appl. No.: |
16/525018 |
Filed: |
July 29, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12444190 |
Apr 13, 2010 |
10363082 |
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PCT/US07/80593 |
Oct 5, 2007 |
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16525018 |
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60849369 |
Oct 5, 2006 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 18/1492 20130101;
A61B 2018/00214 20130101; A61B 18/042 20130101; A61B 2018/1465
20130101; A61B 2018/00267 20130101; A61B 2018/00916 20130101; A61B
2018/1467 20130101; A61B 18/16 20130101 |
International
Class: |
A61B 18/04 20060101
A61B018/04; A61B 18/14 20060101 A61B018/14 |
Claims
An electrosurgical apparatus comprising: a first electrode having a
proximal end and a distal end; a second electrode at least
partially disposed proximate to the distal end of the first
electrode; and a third electrode at least partially disposed
proximate to the proximal end of the first electrode.
2. The electrosurgical apparatus of claim 1, wherein the first
electrode is positioned substantially intermediate the second and
third electrodes.
3. The electrosurgical apparatus of claim 1, wherein the first
electrode is separated from the second and third electrodes by at
least one insulator.
4. The electrosurgical apparatus of claim 1, wherein the first
electrode is generally axially symmetric in shape.
5. The electrosurgical apparatus of claim 1, wherein at least one
of the second electrode and third electrode is generally axially
symmetric in shape.
6. The electrosurgical apparatus of claim 1 wherein the first
electrode comprises a conductive lattice.
7. The electrosurgical apparatus of claim 1, further comprising a
manipulation means in mechanical communication with the at least
one first electrode, the manipulation means configured to apply a
mechanical force to change the shape of the first electrode.
8. The electrosurgical apparatus of claim 7 wherein the
manipulation means is anchored proximate to the second
electrode.
9. The electrosurgical apparatus of claim 1, wherein the first
electrode comprises an active electrode.
10. The electrosurgical apparatus of claim 1, wherein the second
electrode comprises a return electrode.
11. The electrosurgical apparatus of claim 1, wherein the third
electrode comprises a return electrode.
12. The electrosurgical apparatus of claim 1, wherein at least a
portion of the second electrode is surrounded by the first
electrode.
13. The electrosurgical apparatus of claim 1, wherein at least a
portion of the third electrode is surrounded by the first
electrode.
14. The electrosurgical apparatus of claim 1, wherein the first
electrode is in one of the forms in the group consisting of: at
least one coiled wire, braided electrically conductive material,
and woven electrically conductive material.
15. The electrosurgical apparatus of claim 7, wherein the
manipulation means is configured to manipulate the diameter of the
first electrode.
16. The electrosurgical apparatus of claim 1, wherein the ratio of
percent of current flow from the second and third electrodes to the
first electrode is approximately 10-90 percent:90-10 percent.
17. The electrosurgical apparatus of claim 1, wherein the ratio of
percent of current flow from the second and third electrodes to the
first electrode is approximately 20-80 percent:80-20 percent.
18. The electrosurgical apparatus of claim 1, wherein the ratio of
percent of current flow from the second and third electrodes to the
first electrode is approximately 40-60 percent:60-40 percent.
19. The electrosurgical apparatus of claim 1, wherein the ratio of
percent of current flow from the second and third electrodes to the
first electrode is approximately 50:50 percent.
20. The electrosurgical apparatus of claim 1, wherein the first
electrode has an active surface extending less than 270 degrees
around the axis of the electrode assembly.
21.-63. (canceled)
Description
[0001] This application is being filed as a Continuation
Application of U.S. application Ser. No. 12/444,190, filed on Apr.
13, 2010, which is a U.S. National Stage Application under 35
U.S.C. 371 of International Application No. PCT/US2007/080593,
filed on Oct. 5, 2007 and claims priority to U.S. Provisional
Application Ser. No. 60/849,369, filed Oct. 5, 2006; the contents
of which are herein incorporated by reference.
TECHNICAL FIELD
[0002] The present technology relates to medical devices.
Particularly, the present technology relates to electrosurgical
devices.
BACKGROUND
[0003] Electrosurgery is the application of electrical current to
tissue for the purpose of surgically altering the tissue. It is a
method commonly used for a variety of medical procedures including,
but not limited to, resecting or vaporizing tissue (typically by
ablation) associated with warts, benign tumors, and tissue growth
such as that associated with Benign Prostatic Hyperplasia (BPH).
During such procedures, electrosurgery can also be used for
controlling bleeding through coagulation. Electrosurgical devices
generally operate by providing electrical current traveling from an
active electrode through target tissue to a return electrode.
Depending on the characteristics of the energy (voltage, frequency,
wattage, for example) being passed through the tissue, and the
device electrodes (size, shape, distance, for example), the tissue
can be transected, vaporized or coagulated.
[0004] Traditionally there have been two primary types of
electrosurgical equipment: bipolar and monopolar. Bipolar
electrosurgery provides the active and return electrode on the
surgical device itself in close proximity to the targeted site,
while monopolar electrosurgery provides only the active electrode
at the targeted site, and the return electrode is generally a
conductive plate that is secured to the patient's outer skin
surface. In monopolar electrosurgery higher voltages are required
to overcome the associated resistance of the patient's body, which
serves as a necessary part of the circuit. In bipolar
electrosurgery, less input power is needed, but the effect on the
targeted tissue is limited by a number of factors, including the
proximity of the active to the return electrode, the size and shape
of the electrodes, the shape and regularity of the electric field
that is created, and the ratio of the surface area of the return
electrode to the surface area of the active electrode.
[0005] Although present electrosurgery equipment and techniques are
suitable for many applications, a need remains for equipment and
techniques that offer improved ablation and coagulation and greater
control over the ablation and coagulation processes.
SUMMARY
[0006] The technology disclosed herein provides for an
electrosurgical apparatus that offers improved control and
precision in removal of tissue.
[0007] In some embodiments the invention includes an
electrosurgical apparatus having one active electrode and two
return electrodes, the return electrodes are typically positioned
on opposite ends of the active electrode so as to provide balanced
current flow (as appropriate, or controlled imbalanced current flow
as desired) and improved performance with regard to tissue removal,
as well as coagulation of tissue as desired.
[0008] The present invention, by providing (in certain embodiments)
a central active electrode intermediate two return electrodes,
offers significant improvements over preexisting electrosurgical
devices. One problem with prior electrosurgical devices is that
they often have relatively small active electrodes, a problem that
can be countered using the designs of the present invention. Size
and shape of prior electrodes has been restricted due to issues
with near field and far field distances, as well as issues
associated with current density. For example, when the active and
return electrodes are too close to one another, then near field
issues become prominent and the electrodes can arc and be
destroyed. When the electrodes are too far apart, or have a surface
area that is too large, then far field issues arise causing
problems with initiation and creation of a uniform plasma zone
around the active electrode. Far field issues also often require
higher power levels.
[0009] Existing devices, such as many bipolar electrosurgical
devices, often suffer from slow tissue removal rates (less than
lg/min). This is due, in part, to the return surface area to active
surface area ratio requiring that the active electrode be
substantially smaller than the return electrode to provide the
current density required if reliable initiation and maintaining of
the plasma zone is to occur. Unfortunately, a small active surface
area results in increased procedure time (costly and harder on
patient); and reduced tissue removal. Simply increasing the active
surface area does not solve this problem, because it inhibits
initiation, reducing precision, and increasing the chance of
patient injury due to unintended tissue damage. Also, increased
active surface area requires more power to maintain high current
density and counter increased far field distance.
[0010] Furthermore, coagulation/hemostasis is inconsistent and
unreliable with existing devices because of inefficient flow of
current. This problem is due to electrode design, and can arise
during both vaporization (also known as ablation) and spot
coagulation. This can result in additional blood loss; poor
visibility and associated decreases in safety; potential for
"re-bleeds" after the operation requiring additional intervention;
and increased procedure time
[0011] Electrode configurations of the present invention provide
reduce far field distances and allow larger plasma zones resulting
in a method of energy delivery that improves tissue removal rates,
up to for example 50 percent, over existing devices, and provides
consistent initiation and vaporization without more power required.
The active zones can, in some embodiments, also be changed in shape
and size, further improving performance in many implementations.
These improvements also lead, in certain embodiments, to better
hemostasis during vaporization due to the current flow which is
deeper and broader; improved spot coagulation of bleeders because
the hemostasis energy is delivered faster and broader, resulting in
more consistent and reliable effect; and an opportunity for blended
vaporization and coagulation energy delivery to further enhance
performance.
[0012] The result, using the various embodiments of the present
invention, allows for potentially reduced procedure time; greater
tissue removal; improved visibility and safety; reduced blood loss;
faster patient recovery and reduced patient complications.
[0013] The technology of the present invention offers medical
practitioners improved views of the area in which tissue is being
removed, and customizable active areas that allow a single
electrosurgical apparatus to have multiple operational modes,
including two or more tissue removal configurations and two or more
coagulation configurations. The technology allows for changes in
the shape of the electrosurgical apparatus, specifically changes in
shape and orientation of the electrode surfaces, as well as changes
in current delivered to the electrode assembly, so as to allow
adjustments in performance and function.
[0014] In addition, in certain embodiments, the electrosurgical
apparatus allows high tissue removal rates while still maintaining
control and precision of the tissue removal. As noted earlier, in
some embodiments the electrosurgical apparatus can be adjusted,
during a surgical procedure, to modify the size and shape of the
electrodes, as well as to adjust whether specific electrodes
function as active or return electrodes. This allows, for example,
a single electrosurgical apparatus to be switched between tissue
removal at a tip surface of the apparatus or a side surface of the
apparatus. For example, in some implementations the present
invention uses three (or more) electrodes in a row. The active
electrode is switched repeatedly between the distal (tip) electrode
and a middle electrode. The other two (or more) electrodes are left
as return electrodes, maintaining a high ratio of return surface
area to active surface area. In the alternative, the active
electrode can cycle through the three (or more) electrodes to
generate an active surface at a larger area than would otherwise be
possible from having a single fixed active electrode.
[0015] In some implementations one or more of the electrodes is
expandable and/or flexible for good maneuverability and
effectiveness when performing electrosurgery. For example, the
apparatus may be inserted into small cavities and expanded when it
reaches a localized operation site. This expandability may manifest
itself in regard to having one or more electrodes that have a
normal state that is modified before or after a surgical procedure
begins. For example, in one implementation an electrode assembly
having a first diameter is inserted into a patient and subsequently
the diameter of the assembly is expanded. However, in other
implementations the electrode assembly is contracted before
insertion into a patient, and thereafter the assembly is allowed to
expand within the patient.
[0016] The apparatus, through some embodiments, may be expanded in
asymmetrical shapes to accommodate asymmetrical surgery locales, as
well as to provide asymmetric tissue removal and coagulation.
[0017] According to example embodiments, the apparatus produces an
electric field that is substantially symmetric and consistent from
a substantially balanced and symmetric electrode placement.
Additionally, in various embodiments, the ratio of the return
electrode surface area to the active electrode surface area may be
maximized by disposing a return electrode at least partially within
an active electrode, using more than one return electrode in
proximity of the active electrode, or both. Such configurations
allow for fast, safe, and efficient electrosurgical procedures. It
is also possible to apply coagulation and ablation frequencies
simultaneously in those embodiments having multiple electrodes.
[0018] More specifically, the technology disclosed herein has, in
certain embodiments, a first electrode that may contain a second
electrode. The first electrode can partially surround the second
electrode. The assembly may have an additional electrode on the
proximal end of the first electrode and an additional electrode on
the distal end of the first electrode, meaning that the electrode
assembly includes (in some embodiments) a first electrode with
additional electrodes on either ends of the first electrode.
[0019] Furthermore, the first electrode may have a shape and/or
size that can be altered via a manipulation means that is in
mechanical communication with the electrode, such that the diameter
or other aspect of the first electrode can be altered. The
disclosed configurations allow for an increase in the ratio of the
return electrode surface area to the active electrode surface area
relative to the prior art, a consistent and predictable electric
field, an alterability of the proximity between the return and
active electrodes, and/or an alterability of the shape of at least
one electrode.
[0020] In one embodiment, the first electrode is a conductive woven
material that has a circular cross-section that defines a central
cavity. In another embodiment, the first electrode (typically the
active electrode) is constructed of a woven conductive material and
is substantially spherical in shape. In yet another embodiment, the
first electrode comprises a conductive material in the shape of a
helix.
[0021] As noted above, the apparatus itself may be attached to an
electrosurgical generator unit through leads or wires, as is known
in the art. The first electrode is optionally constructed so as to
be flexible, and to define at least a partial cavity within the
electrode, and has a proximal end and a distal end. The first
electrode is not limited to a circular cross section, and may have
a cross section of virtually any shape. The first electrode may be
constructed of coiled wire, braided electrically conductive
material, welded lattice, laser cut or machined lattice, woven
electrically conductive material, any combination thereof, or other
suitable electrically conductive material, especially when such
material is able to be configured to be repeatedly expanded and
contracted. However, it will be appreciated that the first
electrode may be constructed out of coiled wire, braided material,
woven material, etc. even when the first electrode is not
configured to be expanded and contracted. The first electrode could
also be constructed of any other material where structural
flexibility is allowed for shape manipulation. The first electrode
may have a lattice configuration, for example. Additionally, a
cavity defined by the first electrode is not limited to a circular
cross section, and also may have a cross section of virtually any
shape.
[0022] Generally, the apparatus has at least a second electrode in
addition to the first electrode, the second electrode at least
partially disposed proximate to the first electrode, meaning that
the second electrode may be disposed near the proximal end of the
first electrode or near the distal end of the first electrode. The
second electrode and the first electrode should not make direct
conductive contact when the device is in operation, i.e. when a
current is passing between them to remove or coagulate tissue,
otherwise the apparatus will develop an electrical short. Generally
a resistive material will be positioned between the electrodes to
insulate them from each other.
[0023] Additionally, at least a portion of the second electrode may
be contained within the first electrode. There also can be a third
electrode that is disposed proximate to the first electrode,
meaning that the third electrode may be at least disposed on the
proximal end of the first electrode or on the distal end of the
first electrode. The third electrode and the first electrode may
not generally make electrical contact. Additionally, at least a
portion of the third electrode may be contained within the first
electrode.
[0024] In some implementations of the invention, a manipulation
means is in mechanical communication with the first electrode. The
manipulation means may be a means of changing the diameter of the
first electrode, or other electrodes. The manipulation means also
may be a means of changing the shape of the first electrode, or
other electrodes. The manipulation means may be a rod, screw,
solenoid, or similar device that, when engaged, changes the shape
(such as the diameter) of the first electrode by applying a force
either directly or indirectly to the first electrode. The
manipulation means may be engaged through a foot pedal, lever,
button, valve, dial, nut, or any other applicable user-apparatus
interface.
[0025] The above summary of the present invention is not intended
to describe each discussed embodiment of the present invention.
This is the purpose of the figures and the detailed description
that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The technology will now be described in greater detail, by
way of example, with references to the drawings, in which:
[0027] FIG. 1 is a perspective view of an overall system
incorporating one embodiment of the apparatus disclosed herein.
[0028] FIG. 2A is a side view of one embodiment of an electrode
assembly constructed and arranged consistent with the technology
claimed herein.
[0029] FIG. 2B is a side sectional view of the electrode assembly
of FIG. 2A in an alternative position.
[0030] FIG. 2C is a cross sectional view of the electrode assembly
of FIG. 2A.
[0031] FIG. 3A is a side sectional view of an alternative electrode
assembly embodiment consistent with the technology claimed
herein.
[0032] FIG. 3B is a side sectional view of the electrode assembly
of FIG. 3A in an alternative position.
[0033] FIG. 3C is a cross sectional view of the electrode assembly
of FIG. 3A.
[0034] FIG. 4A is a side sectional view of an alternative
embodiment electrode assembly consistent with the technology
claimed herein.
[0035] FIG. 4B is a side sectional view of the apparatus of FIG. 4A
in an alternative position.
[0036] FIG. 4C is a cross sectional view of the apparatus of FIG.
4A.
[0037] FIG. 5A is a side sectional view of an alternative
embodiment consistent with the technology claimed herein.
[0038] FIG. 5B is a side sectional view of the apparatus of FIG. 5A
in an alternative position.
[0039] FIG. 5C is a cross sectional view of the apparatus of FIG.
5A.
[0040] FIG. 6A is a side sectional view of an alternative
embodiment consistent with the technology claimed herein.
[0041] FIG. 6B is a side sectional view of the apparatus of FIG. 6A
in an alternative position.
[0042] FIG. 6C is a cross sectional view of the apparatus of FIG.
6A.
[0043] FIG. 7A is a side view of an alternative embodiment
consistent with the technology claimed herein.
[0044] FIG. 7B is a side sectional view of the apparatus of FIG. 7A
in an alternative position.
[0045] FIG. 7C is a cross sectional view of the apparatus of FIG.
7A.
[0046] FIG. 8A is a side view of use of an example implementation
of the apparatus of the invention, showing the apparatus inserted
into a representation of an expanded prostate, prior to removal of
any prostate tissue.
[0047] FIG. 8B is a side view of use of an example implementation
of the apparatus of the invention, showing the apparatus inserted
into a representation of an expanded prostate after removal of some
prostate tissue.
[0048] FIG. 8C is a side view of use of an example implementation
of the apparatus of the invention, showing the apparatus inserted
into a representation of an expanded prostate and showing the
apparatus with an expanded active electrode to further remove
prostate tissue.
[0049] FIG. 8D is a side view of use of an example implementation
of the apparatus of the invention, showing the apparatus inserted
into a representation of an expanded prostate and showing the
apparatus with an expanded active electrode to further remove
prostate tissue.
[0050] FIG. 9 is a side sectional view of an alternative embodiment
consistent with the technology claimed herein.
[0051] FIG. 10A is a cross sectional view of an example
implementation of the apparatus of the invention.
[0052] FIG. 10B is a cross sectional view of an example
implementation of the apparatus of the invention.
[0053] FIG. 10C is a cross sectional view of an example
implementation of the apparatus of the invention.
DETAILED DESCRIPTION OF THE DRAWINGS
[0054] The technology disclosed herein provides for an
electrosurgical apparatus that offers improved control and
precision in removal of tissue. In some embodiments the
electrosurgical apparatus can be adjusted, during a surgical
procedure, to modify the size and shape of one or more of the
electrodes. In addition, in certain embodiments, specific
electrodes functioning as active or return electrodes can be
changed during a surgical procedure, such as to change an active
electrode into a passive electrode, or to change the frequency of
electrical energy. In addition, in certain embodiments, the
electrosurgical apparatus allows higher tissue removal rates while
still maintaining control and precision.
[0055] In some implementations one or more of the electrodes is
expandable for good maneuverability and effectiveness when
performing electrosurgery. For example, the apparatus may be
inserted into small cavities and expanded when it reaches a
localized operation site. The apparatus, through some embodiments,
may be expanded in asymmetrical shapes to accommodate asymmetrical
surgery locales, as well as to provide asymmetric tissue removal.
In the alternative, such expansion can be symmetric or
substantially symmetric around a central axis.
[0056] Referring now to the figures, various embodiments of the
invention will be described in greater detail. FIG. 1 is a
perspective view of an example system incorporating one embodiment
of an electrosurgical apparatus made in accordance with the
invention. In this example embodiment, an electrosurgical apparatus
100 is connected to an electrosurgical generator 130. The
connection can be made, for example, via a lead, cord, wire, or
cable 110. A user-apparatus interface 120 may be disposed between
the electrosurgical apparatus 100 and the electrosurgical generator
130. In the depicted embodiment, a foot pedal 150 is also connected
to the electrosurgical generator 130 via a lead, cord, wire, or
cable, for example, which may control output of the electrosurgical
generator.
[0057] FIG. 2A shows a side view of one embodiment electrode
assembly 200 constructed in accordance with the invention and
consistent with the technology claimed herein. The assembly
includes a first electrode 210. Near the first electrode 210 is a
second electrode 220 disposed on the distal end 212 of the first
electrode 210, at the tip of the electrode assembly 200. A first
insulator 240 separates the first electrode 210 and the second
electrode 220. Near the first electrode 210 is also a third
electrode 230 positioned on the other end (the proximal end 214,
which is opposite the tip of the assembly 200) of the first
electrode 210. A second insulator 250 separates the first electrode
210 from the third electrode 230.
[0058] The first electrode 210 is constructed so as to be flexible,
to define at least a partial cavity within the electrode, and has a
distal end 212 and a proximal end 214. The first electrode 210 is
not limited to a circular cross section, and may have a cross
section of virtually any shape, including a shape that does not
completely surround the assembly 200. The first electrode 210 may
be at least partially constructed of coiled wire, braided
electrically conductive material, woven electrically conductive
material, or any combination thereof
[0059] The first electrode 210 can also be at least partially
constructed of any other conductive material where structural
flexibility is allowed for shape manipulation. In one embodiment,
the first electrode 210 is a woven conductive material that has a
circular cross-section that defines a central cavity. In one other
embodiment, the first electrode 210 is constructed of a woven
conductive material and is substantially spherical in shape, and
defines a substantially spherical cavity within the electrode. In
yet another embodiment, the first electrode 210 comprises a
conductive material in the shape of a helix that defines an opening
within the helix. The first electrode 210 may have a lattice
configuration, and may be an active electrode.
[0060] As discussed above, proximate (meaning near) to the first
electrode 210 is the second electrode 220 located on the distal end
212 of the first electrode 210. The second electrode 220 may be
constructed of any electrically conductive material, typically a
metal. Proximate to the first electrode 210 is the second electrode
220 disposed on the distal end 212 of the first electrode 210, and
partially contained within the first electrode 210. A first
insulator 240 separates the first electrode 210 from the second
electrode 220. A manipulation means 270 is anchored to the second
electrode 220. The first electrode 210 is typically an active
electrode and the second electrode 220 may be a return
electrode.
[0061] Also proximate to the first electrode 210 is a third
electrode 230. As shown in FIG. 2A, the second electrode 220 and
the third electrode 230 are typically positioned on opposite ends
of the first electrode 210. The third electrode 230 may be
constructed of any electrically conductive material and, like the
second electrode 220, can function as an active or return
electrode, but is typically used as a return electrode. The third
electrode 230 and the first electrode 210 are separated by the
second insulator 250. The second insulator 250 may be constructed
of a high-temperature, electrically insulating material such as
ceramic or silicone.
[0062] Typically, in use the second electrode 220 functions as a
return electrode, although in certain embodiments the second
electrode 220 functions as either a return electrode or an active
electrode by switching the polarity of the electrodes. For example,
it is possible to switch between having the first electrode 210 and
second electrode 220 be the active electrode. In such embodiments
the third electrode 230 is typically kept as a return electrode, so
as to maintain a ratio where the surface area of return electrodes
is significantly greater than the surface area of the active
electrodes. The second electrode 220 and the first electrode 210
are separated by the first insulator 240. The first insulator 240
may be constructed of any high-temperature, electrically insulating
material such as ceramic or silicone. However, it may be desirable
to temporarily remove tissue at the tip of the apparatus 200, in
which case switching functionality to allow the second electrode
220 to be the active electrode is desirable, since tissue will be
removed most at the tip of the assembly 200.
[0063] FIG. 2B is a side sectional view of the apparatus of FIG. 2A
in an alternative position. This view reveals that the second
electrode 220, which is partially disposed on the distal end of the
first electrode 210, is partially contained within the first
electrode 210. In this depicted embodiment, second electrode 220
includes a central shaft 222 that runs down the interior of the
first electrode 210 and connects to a wider head 224. This central
shaft 222 can be integrally formed with the head 224 of the second
electrode 220, such that the second electrode 220 is a single
piece. However, in other embodiments this central shaft 222 can be
an independent piece, although typically in electrical
communication with the head 224.
[0064] In the depicted embodiment, a third insulator 260 surrounds
the partially contained portion of the second electrode 220 to
prevent contact between the first electrode 210 and the second
electrode 220. The third insulator 260 may be constructed of a
high-temperature, electrically insulating material such as ceramic
or silicone, and may be disposed on the second electrode 220. It
will be appreciated that third insulator 260 can cover more or less
of the second electrode than is shown in FIG. 2B. Also revealed
through this side sectional view of the apparatus of FIG. 2A, is
that the first insulator 240, the second insulator 250, and the
third electrode 230 define respective openings through which the
second electrode 220 may pass.
[0065] It will be appreciated that the configuration of electrodes
shown in FIG. 2A and 2B is only representative, and that
alterations in the configuration of the electrodes can be made
without deviating from the spirit and scope of the design. For
example, specifically in reference to FIG. 2B, it will be
appreciated that the portion of the central shaft 222 of the second
electrode 220 surrounded by the first electrode 210 can be
shortened significantly, or even eliminated so that none of the
second electrode 220 is surrounded by the first electrode 210.
Similarly, it is possible to increase the size and/or surface area
of any of the electrodes shown in FIGS. 2A and 2B.
[0066] Referring again to FIG. 2B, attached to the second electrode
220 is a manipulation means 270. The manipulation means is, in this
example, a rod 270 that is in mechanical communication with the
first electrode 210 and is anchored to the second electrode 220.
Thus, although the rod 270 does not actually touch the first
electrode 210, it is in mechanical communication with the first
electrode 210 because movement of the rod mechanically changes the
shape of the first electrode 210.
[0067] In the alternative, the manipulation means 270 may be a rod,
screw, solenoid, or similar device that, when engaged, changes the
shape, diameter, or surface area of the first electrode 210 by
applying a force either directly or indirectly to the first
electrode 210. The manipulation means may be engaged through a foot
pedal, button, lever, valve, dial, nut, or any other applicable
user-apparatus interface. The manipulation means may be a means of
changing the diameter of the first electrode 210. The manipulation
means also may be a means of changing the shape of the first
electrode 210. For example, the manipulation means may be used to
create a protrusion in the first electrode along just one side of
the electrosurgical apparatus, such as that shown and described
later in FIG. 6.
[0068] FIG. 2C is a cross sectional view of the electrode assembly
200 of FIG. 2A in the alternative position demonstrated in FIG. 2B.
The first electrode 210, being expanded, has a larger diameter than
the outside diameter of the second insulator 250. The second
electrode 220, a portion of which is partially contained within the
first electrode 210, has a smaller diameter than the first
electrode, and a smaller diameter than the second insulator 250.
The cavity defined by the first electrode 210 is not limited to a
circular cross section, and also may have a cross section of
virtually any shape. Likewise, the cavity defined by the second
insulator 250 need not be circular.
[0069] FIG. 3A is a side sectional view of an alternative
embodiment of an electrode assembly 300 made in accordance with an
implementation of the invention. This implementation shows the
electrode assembly 300 having just first and second electrodes, in
which a first electrode 310 partially surrounds a second electrode
320. Proximate to a first electrode 310 is a second electrode 320
disposed on the distal end 312 of the first electrode 310, and
partially contained within the first electrode 310. A first
insulator 340 separates the first electrode 310 from the second
electrode 320. A manipulation means 370 is anchored to the second
electrode 320. The first electrode 310 is typically an active
electrode and the second electrode 320 may be a return
electrode.
[0070] While the various apparatuses of the invention will
frequently be used to remove tissue, it should be appreciated that
the active electrodes can also be readily used to deliver energy at
coagulation frequency. The large surface area of the first
electrodes 210, 310, etc. allow a broad delivery of coagulation
energy, thereby allowing aggressive efforts to stop even relatively
large areas of bleeding resulting from tissue removal. Thus, the
present invention offers the opportunity to provide quick,
wide-area coagulation energy by using the large surface area of the
first electrodes 210, 310, etc.
[0071] In further review of FIG. 3, a manipulation means 370 is in
mechanical communication with the first electrode 310, and is
anchored to the second electrode 320 at the end 326 of central
shaft 322. The first electrode 310, first insulator 340, second
electrode 320, manipulation means 370, and leads or wires 380 are
of a similar nature, construct, and materials to those discussed in
FIG. 2A, FIG. 2B, and FIG. 2C, above.
[0072] FIG. 3B is a side sectional view of the apparatus of FIG. 3A
in an alternative position. In FIG. 3B the distal end 312 and
proximal end 314 of the first electrode 310 are drawn closer
together, thus changing the diameter and shape of the first
electrode 310. The manipulation means 370 may be engaged so as to
pull the second electrode 320 toward the proximal end 314 of the
first electrode 310, thereby compressing the first electrode 310
and causing the change in shape and/or diameter.
[0073] FIG. 3C is a cross sectional view of the apparatus of FIG.
3A in the alternative position demonstrated in FIG. 3B. The first
electrode 310 is in a shortened state whereby it becomes wider, and
defines a cavity that at least partially contains the second
electrode 320.
[0074] FIG. 4A is a side sectional view of an alternative
embodiment consistent with the technology of the present invention.
Proximate to a first electrode 410 is a second electrode 430
disposed near (or proximate to) the proximal end of the first
electrode 410. Separating the first electrode 410 from the second
electrode 430 is a first insulator 450. In mechanical communication
with the first electrode 410 is a manipulation means 470, which
extends from a lead or wire to the distal end of the first
electrode 410. The manipulation means 470 may be slidably disposed
within the first electrode 410 and anchored to the tip 490 on the
distal end of the first electrode 410. The first electrode 410,
first insulator 450, second electrode 430, manipulation means 470,
and leads or wires are of a similar nature, construction, and
materials to those discussed in FIG. 2A, FIG. 2B, and FIG. 2C,
above.
[0075] The tip 490 may be an extension of the manipulation means
470, or may be a separate entity constructed out of any material
that allows the manipulation means 470 to be anchored to the distal
end of the first electrode 410. The tip 490 may also be a portion
of the first electrode 410, and be constructed out of substantially
similar material, or the tip 490 can be an extension of either the
first electrode 410 or the manipulation means 470. Thus, electrode
assembly 400 contains two electrodes: An outer electrode (the first
electrode 410) plus a substantially surrounded inner electrode (the
second electrode 430).
[0076] FIG. 4B is a side sectional view of the apparatus of FIG. 4A
in an alternative position. In FIG. 4B the distal end 412 of the
first electrode has been drawn closer to the proximal end 414 than
in FIG. 4A, thus changing the diameter and shape of the first
electrode 410. The manipulation means 470 may be engaged so as to
pull the tip 490 closer to the proximal end of the first electrode
410, thereby compressing the first electrode 410 and causing a
change in diameter.
[0077] FIG. 4C is a cross sectional view of the apparatus of FIG.
4A in the alternative position demonstrated in FIG. 4B. The first
electrode 410 is in an expanded state and defines a cavity that at
least partially contains the second electrode 430. The first
insulator 450 separates the first electrode from the second
electrode 430. Thus, the second electrode 430 may define a passage
through which the manipulation means 470 is disposed. The passage
need not have a circular cross section as shown in FIGS. 4B and 4C,
but could be a variety of shapes that allow sliding or shifting in
position of the manipulation means 470. The passage also need not
be in the center of the second electrode 430, but could be
positioned anywhere through the second electrode 430 so long as the
passage allows sliding or shifting of the manipulation means
470.
[0078] FIG. 5A is a side sectional view of an alternative
embodiment consistent with the technology claimed herein.
Separating a first electrode 510 and a second electrode 520 is a
first insulator 550. A manipulation means 570 extends through a
passage within the first electrode 510 and the second electrode
520. Proximate to the first electrode 510 is the second electrode
520 disposed proximate to the proximal end of the first electrode
510. The second electrode 520 is also at least partially contained
by the first electrode 510. In this embodiment, the second
electrode 520 is, like the first electrode 510, constructed so as
to be flexible, to define at least a partial cavity within the
electrode, and has a proximal end and a distal end. The second
electrode 520 is not limited to a circular cross section, and may
have a cross section of virtually any shape. The second electrode
520 may be at least partially constructed of coiled wire, braided
electrically conductive material, woven electrically conductive
material, or any combination thereof. The second electrode 520 can
also be at least partially constructed of any other conductive
material where structural flexibility is allowed for shape
manipulation. The second electrode 520 may have a lattice
configuration, and may be return electrode.
[0079] As shown, the second electrode 520 may have a distal end
that shares a tip 590 with the distal end of the first electrode
510. If so, then a second insulator would be used to prevent
contact between the distal end of the first electrode 510 and the
distal end of the second electrode 520. The manipulation means 570
then extends through the passage of the first electrode 510 and the
second electrode 520 to the tip of the apparatus. In an alternative
embodiment, the second electrode does not share a tip 590 with the
first electrode, and has a distal end that is separate from the
distal end of the first electrode 510. In such a situation the
manipulation means 570 may extend into the passage though the first
electrode 510 and the second electrode 520, and then extend through
the distal end of the second electrode 520 to the tip 590 of the
first electrode 510.
[0080] The first electrode 510, first insulator 550, manipulation
means 570, and leads or wires are of a similar nature, construct,
and materials to those discussed in FIG. 2A, FIG. 2B, and FIG. 2C,
above.
[0081] FIG. 5B is a side sectional view of the electrode assembly
500 of FIG. 5A in an alternative position. In FIG. 5B the distal
end is positioned closer to the proximal end of the first electrode
510 and the second electrode 520 than in FIG. 5A, thus changing the
diameter and shape of the first electrode 510. The manipulation
means 570 may be engaged so as to pull the tip 590 closer to the
proximal end of the first electrode 510, thereby compressing the
first electrode 510 and the second electrode 520, causing a change
in shape or diameter. In this embodiment of an electrode assembly
500, the diameter of the second electrode 520 changes in
substantially the same proportion to the first electrode 510.
[0082] FIG. 5C is a cross sectional view of the apparatus of FIG.
5A in the alternative position demonstrated in FIG. 5B. The first
electrode 510 is in an expanded state and defines a passage that at
least partially contains the second electrode 520. The second
electrode 520 is also in an expanded state and defines a cavity
that at least partially contains the manipulation means 570.
[0083] The first insulator 550 separates the first electrode 510
from the second electrode 520, and defines a passage that at least
partially contains the manipulation means 570.
[0084] FIG. 6A is a side sectional view of an alternative
embodiment for an electrode assembly 600, the assembly constructed
consistent with the technology claimed herein. Also proximate to
the first electrode 610 is a second electrode 620 partially
disposed on the distal end of the first electrode 610, and also
partially contained within the first electrode 610. The first
electrode 610 may be an active electrode and the second electrode
620 may be a return electrode. The second electrode 620 and the
first electrode 610 are separated by a first insulator 640.
[0085] The manipulation means 670 is in mechanical communication
with the first electrode 610, and is anchored to the second
electrode 620. The manipulation means 670 may be at least partially
disposed in leads or wires 680 connected to the apparatus 600. The
first electrode 610, first insulator 640, second electrode 620,
manipulation means 670, and leads or wires 680 are of a similar
nature, construct, and materials to those discussed in FIG. 2A,
FIG. 2B, and FIG. 2C, above.
[0086] FIG. 6B is a side sectional view of the apparatus of FIG. 6A
in an alternative position. In FIG. 6B the distal end is positioned
closer to the proximal end of the first electrode 610 than in FIG.
6A, thus changing the diameter and shape of the first electrode
610. The manipulation means 670 may be engaged so as to pull the
second electrode 620 closer to the proximal end of the first
electrode 610, thereby compressing the first electrode 610 and
causing a change in shape. In this embodiment the apparatus 600 is
asymmetrical and may be relevant for asymmetrical tissue requiring
electrosurgery.
[0087] FIG. 6C is a cross sectional view of the apparatus of FIG.
6A in the alternative position demonstrated in FIG. 6B. The first
electrode 610 is in an expanded state and defines an opening that
at least partially contains the second electrode 620.
[0088] FIG. 7A is a side view of an alternative embodiment
consistent with the technology claimed herein. Proximate to a first
electrode 710 is a second electrode 720 at least partially disposed
on the distal end of the first electrode 710. The second electrode
720 and the first electrode 710 are separated by a first insulator
740. Also proximate to the first electrode 710 is a third electrode
730. The third electrode 730 and the first electrode 710 are
separated by a second insulator 750. A manipulation means 770 is in
mechanical communication with the first electrode 710, and is
anchored to the second electrode 720. The manipulation means 770
may be at least partially disposed in leads or wires connected to
the apparatus 700. In this illustrative embodiment, the first
electrode 710, and the manipulation means 770 are curved so as to
form an asymmetrical electrode assembly 700.
[0089] It will be appreciated that the first electrode 710 may be
flexible, but formed such that the electrode is curved in its
natural or at rest state, or that the electrode is configured to be
moved between curved and straight positions. Thus, the electrode
can be deflectable, such as to be steerable, or the electrode can
be permanently made to encompass a curve. One advantage of such
deflected and deflectable electrode assemblies is that they can be
used to aid navigation of partially obstructed passageways and
non-linear passageways more easily than a straight assembly. In
addition, the deflected shapes (i.e., the non-linear shapes), can
be used advantageously for some tissue removal and coagulation
processes, improving precision and effectiveness by allowing access
to areas that might be off-axis form the apparatus, and would thus
be more difficult to reach with a straight electrode assembly.
[0090] FIG. 7B is a side sectional view of the apparatus of FIG. 7A
in an alternative position. In FIG. 7B the distal end is positioned
closer to the proximal end of the first electrode 710 than in FIG.
7A, thus changing the diameter and shape of the first electrode
710. The manipulation means 770 may be engaged so as to pull the
second electrode 720 closer to the proximal end of the first
electrode 710, thereby compressing the first electrode 710 and
causing the change in diameter. FIG. 7B illustrates that there may
be asymmetrical expansion of the apparatus 700.
[0091] FIG. 7C is a cross sectional view of the apparatus of FIG.
7A in the alternative position demonstrated in FIG. 7B. The first
electrode 710 is in an expanded state and defines a passage that at
least partially contains the manipulation means 770. The second
insulator 750 that separates the first electrode 710 from the third
electrode 730 defines a cavity that at least partially contains the
manipulation means 770.
[0092] FIG. 8 is a diagram of an example implementation consistent
with the technology claimed herein and according to various
embodiments. The example implementation demonstrates use of various
embodiments of the technology disclosed herein to remove prostatic
tissue associated with benign prostatic hyperplasia (BPH), for
example. The example implementation discussed is merely for
explicative purposes rather than limiting purposes. The apparatus
may be inserted into a urethra in a relatively unexpanded state so
as to extend into the urethra to the site where electrosurgery will
take place. The illustrated urethra includes a narrowing or
occlusion, which is desirably widened or removed. Insertion may be
similar to urinary catheterization.
[0093] When apparatus is extended to the site of the
electrosurgery, the apparatus may be engaged for tissue removal.
The apparatus may be engaged through a user-apparatus interface
such as a foot pedal, button, valve, dial, nut, or any other
applicable user-apparatus interface that is in communication with
the electrosurgical generator. The frequency of the electricity may
be selected for ablation or coagulation, or both.
[0094] As the tissue is removed, the apparatus may be expanded to
increase the working diameter of the apparatus. Expansion may occur
through a user-apparatus interface such as a foot pedal, button,
valve, dial, nut, or any other applicable user-apparatus interface
that is in communication with the manipulation means, discussed
through FIGS. 2-7, above. A greater working diameter of the
apparatus improves tissue removal, including precision of removal,
so as to create a greater internal passageway through the prostate.
When the surgery session is ended, the apparatus may be contracted
again to provide relative ease in the removal of the device.
[0095] The method demonstrated in FIG. 8 is merely one example
implementation of the technology disclosed herein. The technology
could also be used for other open, laparoscopic, or endoluminal
surgical procedures. Thus, FIG. 8A is a side view of use of an
example implementation of the apparatus of the invention, showing
the apparatus inserted into a urethra, prior to removal of any
tissue at the narrowing caused by prostate tissue. FIG. 8B is a
side view of use of an example implementation of the apparatus of
the invention, showing the apparatus inserted into a urethra, after
removal of any tissue at the narrowing has started. FIG. 8C is a
side view of use of an example implementation of the apparatus of
the invention, showing after removal of any tissue at the narrowing
has started, with an expanded active electrode to further remove
prostate tissue. FIG. 8D is a side view of use of an example
implementation of the apparatus of the invention, showing the
apparatus showing the apparatus with an expanded active electrode
to further remove tissue (or to apply coagulation energy.
[0096] FIG. 9 is a side sectional view of an alternative embodiment
assembly 900 consistent with the technology claimed herein, wherein
first electrode 910 has second electrode 920 and third electrode
930 positioned on alternative ends. In this embodiment, second
electrode 920 has significantly more surface area than third
electrode 930. It will be appreciated, however, as discussed
earlier in this application, that the size difference may be
reversed, so that the second electrode has significantly less
surface area than the third electrode. Also shown are first and
second insulators, 940 and 950. In the embodiment shown in FIG. 9,
the energy delivered to each electrode can be adjusted to control
the location and nature of delivered energy. In most embodiments
the first electrode 910 is active, while the second electrode 920
and third electrode 930 are returns. However, the function of the
first and second electrodes can be reversed, so that the second
electrode 920 is active and the first electrode 910 is a return
(along with the third electrode 920, which would typically remain
as a return electrode so as to maintain significantly greater
surface area for the return electrodes). The alternation of
function between the first and second electrodes can be automatic
or manual. Also, it can be cycled rapidly to create a boring
electrode that both cuts at the tip (second electrode 920) and at
the sides (first electrode 910). Notably, it is also possible to
switch the third electrode into this rotation, such that the third
electrode 930 becomes active while the first and second electrodes
910, 920 are returns. Also, it will be appreciated that any and all
of these electrodes can be used to deliver coagulation energy, not
just ablation energy. In one desirable mode, coagulation energy is
delivered between the second and third electrodes 920, 930.
[0097] FIGS. 10A to 10C are cross sectional views of example
implementations of the invention, showing different configurations
for first electrodes. In FIG. 10A, the first electrode extends
about 270 degrees around the outside of the assembly; the first
electrode extends about 90 degrees around the assembly of FIG. 10B;
and the first electrode extends about 180 degrees around the
outside of the assembly of FIG. 10C. The approximate extent of the
electrodes is shown by dashed lines. It will be appreciated, as
shown in these examples, that various shapes of first electrodes
can be used, and the first electrodes can be configured to cover
relatively large or small parts of the circumference of the
electrode assembly.
* * * * *