U.S. patent application number 17/825410 was filed with the patent office on 2022-09-08 for electrode assembly.
This patent application is currently assigned to GYRUS MEDICAL LIMITED. The applicant listed for this patent is GYRUS MEDICAL LIMITED. Invention is credited to Anthony K. ATWELL, Marno NAGTEGAAL.
Application Number | 20220280222 17/825410 |
Document ID | / |
Family ID | 1000006362348 |
Filed Date | 2022-09-08 |
United States Patent
Application |
20220280222 |
Kind Code |
A1 |
ATWELL; Anthony K. ; et
al. |
September 8, 2022 |
ELECTRODE ASSEMBLY
Abstract
An electrode assembly is provided for use in a resectoscope, the
electrode assembly comprising an elongate shaft, at least one arm,
first connection means for connecting the arm to a source of
electrosurgical energy, and a tissue treatment element at the end
of the arm. The arm includes a suction lumen extending from a
proximal end to a distal end, the distal end of the suction lumen
terminating in the general region of the tissue treatment element,
and the proximal end of the suction lumen including second
connection means for connecting the suction lumen to a source of
suction.
Inventors: |
ATWELL; Anthony K.;
(Newport, GB) ; NAGTEGAAL; Marno; (Cardiff,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GYRUS MEDICAL LIMITED |
Cardiff |
|
GB |
|
|
Assignee: |
GYRUS MEDICAL LIMITED
Cardiff
GB
|
Family ID: |
1000006362348 |
Appl. No.: |
17/825410 |
Filed: |
May 26, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16111533 |
Aug 24, 2018 |
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17825410 |
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14483673 |
Sep 11, 2014 |
10179025 |
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16111533 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 17/00234 20130101;
A61B 18/14 20130101; A61B 2018/1475 20130101; A61B 2018/00547
20130101; A61B 2017/4216 20130101; A61B 2218/007 20130101; A61B
2017/00274 20130101; A61B 2018/1407 20130101; A61B 2018/00035
20130101; A61B 2218/002 20130101; A61B 18/149 20130101; A61B
2018/1405 20130101 |
International
Class: |
A61B 18/14 20060101
A61B018/14; A61B 17/00 20060101 A61B017/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 13, 2013 |
GB |
1316287.0 |
Claims
1. An electrode assembly for use in a resectoscope, the electrode
assembly comprising: an elongate shaft having a longitudinal axis,
at least one arm extending from the shaft and angled relative to
the longitudinal axis of the shaft, a first connection portion
configured to connect the arm to a source of electrosurgical
energy, and a tissue treatment element at a distal end of the arm,
wherein: the arm includes a suction lumen extending from a proximal
end to a distal end, the distal end of the suction lumen
terminating at a suction aperture located in the tissue treatment
element, the suction aperture being in communication with the
suction lumen; and the proximal end of the suction lumen including
a second connection portion configured to connect the suction lumen
to a source of suction; and wherein the electrode assembly includes
at least two arms.
2. The electrode assembly according to claim 1, wherein the tissue
treatment element depends from both of the arms.
3. The electrode assembly according to claim 1, wherein both of the
arms are provided with a suction lumen.
4. The electrode assembly according to claim 1, wherein the at
least one arm includes a wire constituting the first connection
means for connecting the arm to a source of electrosurgical energy,
and a hollow tube constituting the suction lumen.
5. The electrode assembly according to claim 4, wherein the hollow
tube surrounds the wire.
6. The electrode assembly according to claim 4, wherein the wire is
a rigid wire constituting the structural support for the tissue
treatment element.
7. The electrode assembly according to claim 1, wherein the at
least one arm includes a hollow tube constituting both the suction
lumen and the first connection means for connecting the arm to a
source of electrosurgical energy.
8. The electrode assembly according to claim 7, wherein the hollow
tube constitutes the structural support for the tissue treatment
element.
9. The electrode assembly according to claim 1, wherein the tissue
treatment element comprises any of: a cutting loop, a roller
electrode, a slider electrode, or a button electrode.
Description
[0001] This is a Division of U.S. application Ser. No. 16/111,533
filed Aug. 24, 2018, which is a divisional of U.S. application Ser.
No. 14/483,673 filed Sep. 11, 2014, which claims the benefit of
British Application No. GB 1316287.0 filed Sep. 13, 2013. The
disclosures of the prior applications are hereby incorporated by
reference herein in their entireties.
TECHNICAL FIELD
[0002] Embodiments of this invention relate to an electrode
assembly for a surgical instrument for the treatment of tissue,
particularly an electrosurgical endoscopic instrument. Such systems
are commonly used for the vaporisation and/or coagulation of tissue
in surgical intervention, most commonly in "keyhole" or minimally
invasive surgery.
BACKGROUND TO THE INVENTION AND PRIOR ART
[0003] One type of electrosurgical procedure is endoscopic
urological surgery using a resectoscope. Such systems are well
known in the art, examples being given in U.S. Pat. Nos. 5,007,907
and 6,322,494. Such systems include an electrosurgical instrument
deployable by means of a resectoscope, and an electrosurgical
generator powering the instrument. Instruments used in
electrosurgical urology surgery are either bipolar, in which case
two electrodes are present at the distal end of the instrument, or
monopolar, in which case one electrode is present on the instrument
and a second electrode is provided in the form of a patient return
plate.
[0004] Bipolar urological surgery is generally carried out as an
"underwater" procedure, with the electrodes immersed in a
conductive fluid such as normal saline. Monopolar urological
surgery is also carried out with the active electrode immersed in a
fluid, but in this case the fluid is generally a non-conducting
fluid such as glycine. In monopolar surgery the return electrode is
a remote patient plate attached to the patient at an area away from
the surgical site.
[0005] In either arrangement, fluid is introduced to the surgical
site and extracted therefrom, usually using irrigation and suction
passages within the resectoscope. However, the effective
circulation of fluid within the surgical site is difficult to
achieve, and fluid adjacent the electrode or electrodes can become
elevated in temperature. If the temperature of the fluid rises
locally to excessive levels, unwanted tissue damage can occur. To
avoid this, the flow rate of the fluid circulating through the
surgical site can be increased. However, while this may be
sufficient to reduce the temperature of the fluid adjacent the
electrode or electrodes, too high a fluid flow can prevent the
electrode or electrodes from functioning correctly. For example, an
electrode may be incapable of "firing up" and vaporising tissue if
the fluid is flowing past the electrode too quickly for an area of
plasma to form around the electrode.
SUMMARY OF THE INVENTION
[0006] Embodiments of the present invention provide a solution to
this problem of fluid circulation, in that they avoid tissue damage
by excessive fluid temperatures without requiring an overall high
fluid flow rate. Accordingly, an electrode assembly is provided for
use in a resectoscope, the electrode assembly comprising an
elongate shaft having a longitudinal axis, at least one arm
depending from the shaft and angled to the longitudinal axis of the
shaft, first connection means for connecting the arm to a source of
electrosurgical energy, and a tissue treatment element at the end
of the arm, wherein the arm includes a suction lumen extending from
a proximal end to a distal end, the distal end of the suction lumen
terminating in the general region of the tissue treatment element,
and the proximal end of the suction lumen including second
connection means for connecting the suction lumen to a source of
suction.
[0007] The suction lumen is capable of extracting fluid from the
immediate vicinity of the tissue treatment element. In this way,
heated fluid adjacent the tissue treatment element is immediately
evacuated from the surgical site, thereby avoiding any unwanted
tissue damage.
[0008] Conceivably, the arm includes a wire constituting the first
connection means for connecting the arm to a source of
electrosurgical energy, and a hollow tube constituting the suction
lumen. Conveniently, the hollow tube surrounds the wire, with the
wire running within the hollow tube. In this way, the hollow tube
provides a suction lumen surrounding the wire. Alternatively, the
hollow tube is separate from the wire, with the wire constituting
an electrical connection for the tissue treatment element and the
hollow tube constituting the suction lumen. Whichever arrangement
is employed, the wire is preferably a rigid wire constituting the
structural support for the tissue treatment element, as well as
providing an electrical connection for the tissue treatment
element.
[0009] Alternatively, the arm includes a hollow tube constituting
both the suction lumen and the first connection means for
connecting the arm to a source of electrosurgical energy. In this
arrangement, the hollow tube itself constitutes the structural
support for the tissue treatment element. Typically, the hollow
tube provides three functions, namely providing the suction lumen,
providing an electrical connection for the tissue treatment
element, and thirdly providing the structural support for the
tissue treatment element. In its simplest form, the arm is in the
form of a hollow tube, and the hollow tube constitutes the arm.
[0010] In one convenient arrangement, the electrode assembly
includes at least two arms, in which case the tissue treatment
element conveniently depends from both of the arms. Where two arms
are provided, preferably both of the arms are provided with a
hollow tube forming a suction lumen.
[0011] The tissue treatment element is conveniently a cutting loop,
a roller electrode, a slider electrode or a button electrode. The
tissue treatment element conveniently constitutes the active
electrode in a bipolar electrode arrangement, with a return
electrode being present elsewhere on the electrode assembly. The
return electrode is conceivably carried on the at least one arm,
and electrically insulated from the arm and the tissue treatment
element by means of an insulator. Alternatively, the tissue
treatment element is part of a monopolar arrangement, with a remote
patient plate constituting a return electrode. Whichever type of
treatment element is employed, the tissue treatment element is
capable of tissue cutting or the coagulation of tissue, while the
heated fluid is evacuated from the surgical site via the hollow
tube.
[0012] The tissue treatment element conveniently includes at least
one aperture in communication with the suction lumen. In this way,
the suction from the suction lumen is delivered right at the
location of the tissue treatment element. Conceivably, the tissue
treatment element includes a plurality of apertures in
communication with the suction lumen. Alternatively or
additionally, the at least one arm includes at least one aperture
in communication with the suction lumen. In this way, fluid heated
by the tissue treatment element is drawn into the at least one arm
via the aperture and into the suction lumen, to be drawn away from
the surgical site. Conceivably, the at least one arm includes a
suction hood adapted to direct material in the general region of
the tissue treatment element into the suction lumen.
[0013] In embodiments of the invention the arm depends from the
shaft at an angle to the longitudinal axis of the shaft sufficient
that the tissue treatment element at the end of the arm is able to
present a usable electrosurgical electrode surface to tissue that
in use would be located to the side of the elongate shaft, rather
than to the front thereof. That is, the angle should be
sufficiently large that a suitably sized electrosurgical electrode
surface of the tissue treatment element to provide for tissue
treatment faces in a direction substantially orthogonal to the
direction of the longitudinal axis. For example, in some
embodiments the arm may depend from the shaft at an angle to the
longitudinal axis of the elongate shaft of for example in excess of
30 degrees, or in more preferred embodiments of in excess of 45
degrees.
[0014] Embodiments of the invention further include a resectoscope
including at least a frame, a sheath supported on the frame and
defining a first lumen, a working element movable with respect to
the frame, and an electrode assembly movable with the working
element and within the sheath, the electrode assembly comprising at
least one electrode and elongate conductive means for supplying
electrosurgical power to said at least one electrode from the
proximal end of the conductive means, the electrode assembly being
provided with an additional lumen, such that the first lumen is
capable of the general removal of matter at the distal end of the
sheath, while the additional lumen is capable of the removal of
fluid from the immediate vicinity of the electrode.
[0015] Conveniently, the elongate conductive means is housed within
a hollow tube, the hollow tube constituting the additional lumen.
Alternatively, the elongate conductive means is itself a hollow
tube, the hollow tube constituting the additional lumen.
[0016] The resectoscope conceivably also includes a second lumen,
which can be used for the supply of fluid to the surgical site. In
this resectoscope, the general circulation of fluid is achieved by
means of the first and second lumens, with fluid being supplied
through the first lumen and removed through the second lumen. The
additional lumen, associated with the electrode assembly, provides
a passage through which fluid can be removed from the immediate
vicinity of the electrode. Heated fluid adjacent the electrode is
immediately evacuated from the surgical site, in addition to the
general circulation of the fluid. In this way any unwanted tissue
damage is avoided, as the hottest fluid is taken away from the
surgical site before it can cause any problems.
[0017] As before, the electrode assembly conveniently comprises two
elongate conductive arms with the electrode depending therefrom.
Conveniently, each of the conductive arms is provided with an
additional lumen. The resectoscope preferably includes a connector
for connecting the additional lumen or lumens to a source of
suction, as well as a connector for connecting the first lumen to a
source of suction. In this way, the first lumen and the additional
lumen can be connected to a suction source, or separate suction
sources, so as to evacuate fluid from the surgical site.
[0018] Embodiments of the invention further include a method of
surgically treating tissue comprising the steps of [0019] i)
introducing a resectoscope into a surgical site within the body of
a patient, the resectoscope including a lumen and at least one
elongate electrode assembly movable within the lumen, the elongate
electrode assembly comprising an electrode element and an elongate
conductive element provided with a suction lumen, [0020] ii)
introducing a fluid into the surgical site, [0021] iii) manoeuvring
the electrode assembly such that the electrode element is adjacent
tissue to be treated, [0022] iv) activating the electrode element
with a source of electrosurgical energy, [0023] v) allowing fluid
to exit the surgical site via the lumen within the resectoscope so
as to remove fluid and/or tissue debris from the surgical site, and
[0024] vi) supplying suction to the suction lumen of the elongate
conductive element so as to remove heated fluid from the region of
the electrode element.
[0025] The method conveniently includes the step of supplying
suction to the lumen within the resectoscope so as to remove fluid
and/or tissue debris from the surgical site. Conceivably, the fluid
is a conductive fluid, such as normal saline.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Embodiments of the invention will now be further described,
by way of example only, with reference to the accompanying
drawings, in which:
[0027] FIG. 1 is a perspective view of an electrosurgical system
including an electrode assembly in accordance with an embodiment of
the present invention,
[0028] FIG. 2 is an exploded view of a resectoscopic instrument
used as part of the electrosurgical system of FIG. 1,
[0029] FIG. 3 is a schematic sectional side view of the shaft of an
instrument used as part of the electrosurgical system of FIG.
1,
[0030] FIGS. 4A & 4B are underneath and end views respectively
of a part of an electrode assembly in accordance with an embodiment
of the present invention,
[0031] FIGS. 5A & 5B are underneath and end views respectively
of a part of an alternative embodiment of electrode assembly in
accordance with an embodiment of the present invention, FIGS. 6A,
6B & 6C are underneath, end and sectional side views
respectively of a part of a further alternative embodiment of
electrode assembly in accordance with an embodiment of the present
invention, and
[0032] FIG. 7 is a schematic side view of a further alternative
embodiment of electrode assembly in accordance with an embodiment
of the present invention.
DESCRIPTION OF THE EMBODIMENTS
[0033] Referring to FIG. 1, a generator 1 has an output socket 2
providing a radio frequency (RF) output for an instrument 3 via a
connection cord 4. Activation of the generator may be performed
from the instrument 3 via a connection in cord 4 or by means of a
footswitch unit 5, as shown, connected to the rear of the generator
by a footswitch connection cord 6. In the illustrated embodiment
footswitch unit 5 has two footswitch pedals 7 and 8 for selecting a
coagulation mode and a cutting mode of the generator respectively.
The generator front panel has push buttons 9 and 10 for
respectively setting coagulation and cutting power levels, which
are indicated in a display 11. Push buttons 12 are provided as a
means for selection between alternative coagulation and cutting
waveforms.
[0034] As shown in FIG. 2, the instrument 3 is deployed through a
resectoscope 13 including an inner sheath 14, an outer sheath 15,
and a rod lens telescope/light source assembly 16. The instrument 3
is part of a working element, indicated generally by the reference
W, to the right of the dotted line shown in FIG. 2, and including a
bipolar electrode assembly 17.
[0035] The sheaths 14 and 15 provide for the circulation of a fluid
medium to an operating site, with the outer sheath 15 being used
for fluid delivery via input connector 18, and the inner sheath
being used for aspiration of the fluid via suction connector 30.
The outer sheath 15 locks over the inner sheath 14, forming a
watertight seal. Typically, the inner sheath 14 has a diameter of
24 Fr, and the outer sheath 15 has a diameter of 27 Fr. The
telescope assembly 16 provides the means of illuminating and
viewing the operative site via a light source (not shown) connected
thereto by a connector 19. The viewing angle of the telescope is
generally at 30.degree. to its axis.
[0036] The working element W may be either passive or active, that
is to say the cutting stroke of the electrode may be as the result
of a spring bias or against the force of a spring bias. The
telescope assembly 16 includes a telescope support tube 20 having a
telescope connector 21 at its proximal end, and a sealing block 22
located part way along the support tube 20, the inner sheath 14
being connected to the sealing block. Both of these interfaces are
watertight. An electrode support tube 23 is attached to the
underside of the telescope support tube 20 on the distal side of
the sealing block 22 for the majority of its length. Two
spring-loaded links 24 and an insulation block 25, located between
the sealing block 22 and the telescope connector 21, make up the
mechanism. The active mechanism is arranged so that the
spring-loaded links 24 assist the forward stroke, while, in the
passive version the links aid the backward stroke. In general, the
range of travel is about 25 mm.
[0037] The bipolar electrode assembly 17 includes an active
electrode 26 in the form of a loop, roller, slider or button, and a
return electrode 27 located on the shaft of the electrode assembly.
The electrodes 26 & 27 are connected to the generator 1 via
cord 4 connected via socket 28. The electrode support tube 23 is
also formed of electrically conductive material, and constitutes a
further return electrode, also connected to the generator 1 via
cord 4.
[0038] FIG. 3 shows the inner and outer sheaths 14 & 15, with
the interior of the outer sheath 15 constituting a fluid supply
lumen 31, and the interior of the inner sheath 14 constituting a
fluid evacuation lumen 32. The electrode assembly 17 is present
within the inner sheath 14, and includes a hollow tubular shaft 33,
the inside of the shaft forming a suction lumen 34. The active
electrode 26 depends from the shaft 33, the electrode in this
instance being in the form of a button 35. FIGS. 4A & 4B show
that the button 35 has an aperture 36 communicating with the
suction lumen 34. The tubular shaft 33 has a proximal aperture 37,
such that the suction lumen 34 is in communication with the fluid
evacuation lumen 32.
[0039] Regarding the angle at which the active electrode 26 depends
from the shaft 33, in this embodiment, and the other embodiments
described below, the active electrode depends from the shaft 33 at
an angle of 90 degrees to the longitudinal axis of the instrument 3
(and hence the inner and outer sheaths 14 and 15, and telescope
assembly 16). In other embodiments, however, the active electrode
26 may depend at a different, lesser angle. However, the angle
should be such that the active electrode is able to present a
suitably sized tissue treatment surface to tissue that is located
to the side of the side of the end of the instrument 3. That is,
the angle should be sufficiently large that the active electrode 26
presents a suitably sized tissue treatment surface in a direction
substantially orthogonal to the direction of the longitudinal axis
of the instrument 3. For example, in some embodiments the active
electrode 26 may depend from the shaft 33 at an angle to the
longitudinal axis of the instrument 3 of for example in excess of
30 degrees, or in more preferred embodiments of in excess of 45
degrees.
[0040] When the instrument 3 is in use, an electrically conductive
fluid such as normal saline is supplied to the surgical site via
fluid supply lumen 31, and removed via fluid evacuation lumen 32
such that the fluid circulates through the surgical site. The
electrosurgical generator 1 supplies RF energy to the electrode 26,
and the energy is transmitted into the conductive fluid, which
heats up accordingly. Heated fluid in the immediate vicinity of the
electrode 26 is drawn through the aperture 36 into the suction
lumen 34, and is aspirated away from the surgical site via the
fluid evacuation lumen 32.
[0041] FIGS. 5A & 5B show an alternative design of electrode
assembly 17, in which the button 35 is supported from two arms 38
& 39, one arm 38 being hollow and forming the suction lumen 34.
As seen in FIG. 5A, aperture 36 is located off-centre with respect
to the button 35, and communicates only with the hollow arm 38. As
before, the aperture 36 and suction lumen 34 helps to aspirate
heated fluid away from the electrode 26, to avoid heating of the
fluid to a temperature at which unwanted tissue damage is a factor.
The aspiration of the fluid through the suction aperture 36 is in
addition to the general circulation of fluid through the lumens 31
& 32, which provide for the replenishment of the fluid on a
regular basis.
[0042] FIGS. 6A to 6C show an alternative embodiment of electrode
assembly 17 in which the button 35 is supported by a single arm 40
in the form of a hollow tube 41, an electrical lead 42 for the
button 35 running inside the hollow tube 41. A suction aperture 36
is provided in the button 35 as previously described, such that
fluid adjacent the button 35 can be aspirated through the suction
aperture 36 and into the hollow tube 41.
[0043] FIG. 7 shows a further design of electrode assembly 17 in
which the button 35 is supported by a single hollow arm 40, the arm
40 containing the suction aperture 36. Surrounding the aperture 36
is a hood 43, shaped so as to direct heated saline and other debris
towards the aperture 36. Once drawn into the aperture 36, the
heated saline is aspirated away from the surgical site via the
hollow arm 40, and the suction lumen 34 to which it is
connected.
[0044] Those skilled in the art will appreciate that arrangements
other than those described above can be employed without departing
from the scope of the present invention. For example, while the
embodiment of FIGS. 5A to 5C only uses one of the arms 38 & 39
as a suction lumen, an alternative arrangement in which both arms
are hollow and provide suction lumens can easily be envisaged. The
key feature is that an electrode assembly not only provides an
electrical pathway for the energising of an electrode, but also a
suction lumen for the removal of fluid from the immediate vicinity
of the electrode.
* * * * *