U.S. patent application number 15/344592 was filed with the patent office on 2020-09-17 for sealing and/or cutting instrument.
This patent application is currently assigned to Domain Surgical, Inc.. The applicant listed for this patent is Domain Surgical, Inc.. Invention is credited to Kent Beck, Philip Eggers, Kim H. Manwaring, Preston Manwaring, David J. McNally, Josh Middel, Mark Stringham, David Wright.
Application Number | 20200289186 15/344592 |
Document ID | / |
Family ID | 1000005059746 |
Filed Date | 2020-09-17 |
View All Diagrams
United States Patent
Application |
20200289186 |
Kind Code |
A9 |
Manwaring; Kim H. ; et
al. |
September 17, 2020 |
SEALING AND/OR CUTTING INSTRUMENT
Abstract
A sealing and/or cutting instrument having a thermally active
surface or element which may be used to seal and then cut tissue,
ducts, vessels, etc., apart. The instrument may include a thermally
active surface or element comprised of a conductor covered with a
ferromagnetic material. The instrument may contact tissue with one
or more surfaces comprised of a non-stick material. A sensor in
communication with the instrument may be used to monitor a
therapeutic procedure and signal when sealing and/or cutting of a
tissue is complete.
Inventors: |
Manwaring; Kim H.; (Phoenix,
AZ) ; McNally; David J.; (Salt Lake City, UT)
; Eggers; Philip; (Cottonwood Heights, UT) ;
Manwaring; Preston; (Farmington, UT) ; Stringham;
Mark; (Kearns, UT) ; Beck; Kent; (Layton,
UT) ; Wright; David; (Littleton, CO) ; Middel;
Josh; (Littleton, CO) |
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Applicant: |
Name |
City |
State |
Country |
Type |
Domain Surgical, Inc. |
Salt Lake City |
UT |
US |
|
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Assignee: |
Domain Surgical, Inc.
Salt Lake City
UT
|
Prior
Publication: |
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Document Identifier |
Publication Date |
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US 20170209200 A1 |
July 27, 2017 |
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Family ID: |
1000005059746 |
Appl. No.: |
15/344592 |
Filed: |
November 7, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13614226 |
Sep 13, 2012 |
9526558 |
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15344592 |
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61534322 |
Sep 13, 2011 |
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61534047 |
Sep 13, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 18/10 20130101;
A61B 2017/00876 20130101; A61B 18/085 20130101 |
International
Class: |
A61B 18/08 20060101
A61B018/08; A61B 18/10 20060101 A61B018/10 |
Claims
1.-24. (canceled)
25. A surgical instrument, comprising: a first arm having a
proximal end and a distal end; a second arm having a proximal end
and a distal end, the second arm physically coupled to the first
arm, the first arm and the second arm movable toward one another; a
ferromagnetic heater physically coupled to the first arm at a
position adjacent the distal end of the first arm; and a sensor
physically coupled to the second arm at a position adjacent the
distal end of the second arm, the sensor monitors at least one
property of tissue, if any, positioned between the ferromagnetic
heater and the sensor.
26. The surgical instrument of claim 25 wherein the ferromagnetic
heater includes a conductor and a ferromagnetic material disposed
about the conductor, the conductor coupleable to an electrical
power source, wherein electrical power passing through the
conductor causes the ferromagnetic material to heat.
27. The surgical instrument of claim 26, further comprising: a
cable that couples the conductor to the electrical power
source.
28. The surgical instrument of claim 25 wherein the sensor
comprises a temperature sensor.
29. The surgical instrument of claim 25 wherein the sensor monitors
a change in a standing wave ratio of electrical energy applied to
the tissue, if any, via the ferromagnetic heater.
30. The surgical instrument of claim 25 wherein the sensor monitors
at least one of conductivity, moisture content and impedance of the
tissue, if any, positioned between the ferromagnetic heater and the
sensor.
31. The surgical instrument of claim 25 wherein the sensor provides
an indication of a transition from one of a sealing procedure and a
cutting procedure to the other of a sealing procedure and a cutting
procedure.
32. The surgical instrument of claim 25 wherein the sensor provides
a status indication of at least one of a sealing procedure and a
cutting procedure.
33. The surgical instrument of claim 32, further comprising: a
power supply that supplies electrical power to the ferromagnetic
heater, the power supply communicatively coupled to the sensor, the
power supply automatically adjusts the electrical power supplied to
the ferromagnetic heater based on the status indication provided by
the sensor.
34. The surgical instrument of claim 25 wherein the second arm
includes a surface that faces the first arm, and the sensor is
positioned on the surface.
35. The surgical instrument of claim 25 wherein the ferromagnetic
heater comprises a rigid loop.
36. A method of treating tissue, comprising: positioning tissue
between a ferromagnetic heater that is physically coupled to a
distal region of a first arm of a surgical instrument and a sensor
that is physically coupled to a distal region of a second arm of
the surgical instrument, the first arm and the second arm
physically coupled to one another; moving the distal region of the
first arm and the distal region of the second arm toward one
another to bring the ferromagnetic heater and the sensor into
contact with the tissue; delivering electrical energy to the
ferromagnetic heater to apply heat to the tissue; and monitoring,
by the sensor, at least one property of the tissue while the
ferromagnetic heater applies heat to the tissue.
37. The method of claim 36 wherein delivering electrical energy to
the ferromagnetic heater comprises delivering the electrical energy
through a conductor and heating a ferromagnetic material disposed
about the conductor.
38. The method of claim 36 wherein delivering electrical energy to
the ferromagnetic heater comprises coupling the ferromagnetic
heater to a power source in a closed circuit.
39. The method of claim 36 wherein monitoring the at least one
property of the tissue comprises monitoring a temperature of the
tissue.
40. The method of claim 36 wherein monitoring the at least one
property of the tissue comprises monitoring at least one of:
conductivity, moisture content and impedance of the tissue.
41. The method of claim 36, further comprising: providing, by the
sensor, a status indication of at least one of a sealing procedure
and a cutting procedure.
42. The method of claim 41, further comprising: automatically
adjusting the delivered electrical power based on the status
indication provided by the sensor.
43. A surgical instrument, comprising: a first arm having a
proximal end and a distal end; a first distal tip at the distal end
of the first arm, the first distal tip having a first medial region
positioned between a first lateral region and a second lateral
region; a second arm having a proximal end and a distal end; a
second distal tip at the distal end of the second arm, the second
distal tip having a second medial region positioned between a third
lateral region and a fourth lateral region, the second arm
physically coupled to the first arm with the second medial region
opposed to the first medial region, the first lateral region
opposed to the third lateral region, and the fourth lateral region
opposed to the second lateral region, and the distal end of the
first arm and the distal end of the second arm movable toward and
away from one another between an open configuration and a closed
configuration, where in the open configuration the second medial
region of the second distal tip is spaced apart from the first
medial region of the first distal tip and in the closed
configuration: i) the second medial region of the second distal tip
contacts the first medial region of the first distal tip, ii) the
third lateral region of the second distal tip is spaced apart from
the first lateral region of the first distal tip, and iii) the
fourth lateral region of the second distal tip is spaced apart from
the second lateral region of the first distal tip, the first
lateral region of the first distal tip and the third lateral region
of the second distal tip delimiting a first sealing zone
therebetween; the second lateral region of the first distal tip and
the fourth lateral region of the second distal tip delimiting a
second sealing zone therebetween; and the first medial region of
the first distal tip and the second medial region of the second
distal tip delimiting a cutting zone therebetween; and a
ferromagnetic heater on at least one of the first distal tip and
the second distal tip.
44. The surgical instrument of claim 43, further comprising: a heat
spreader positioned adjacent to the ferromagnetic heater in the
cutting zone.
45. The surgical instrument of claim 44 wherein the heat spreader
concentrates heat from the ferromagnetic heater in the cutting
zone.
46. The surgical instrument of claim 43 wherein the first distal
tip has a first curved surface and the second distal tip has a
second curved surface, the first and the second curved surfaces
having respective vertices aligned with one another.
47. The surgical instrument of claim 46 wherein the first curved
surface and the second curved surface have a same curvature.
Description
PRIORITY
[0001] The present application claims the benefit of U.S.
Provisional Patent Application Ser. No. 61/534,047, filed Sep. 13,
2011 and U.S. Provisional Patent Application Ser. No. 61/534,322,
filed Sep. 13, 2011, which are incorporated herein by reference in
their entirety.
THE FIELD OF THE INVENTION
[0002] The present invention relates to surgical instruments. More
specifically, the present invention relates to tissue cutting and
sealing instruments.
BACKGROUND
[0003] Human and animal bodies contain a number of ducts for moving
fluids and material, such as blood vessels for carrying blood, the
digestive tract for transporting and processing food, reproductive
ducts for transporting reproductive fluids and gastric ducts for
passing bile and other fluids. (As used herein duct is used broadly
to encompass ducts, vessels, tubes and other ducts in a human or
animal body. Bodies also include various tissues for performing
functions necessary to maintain the body. During surgery, these
ducts or tissues may get in the way of the surgical procedure or
may need to be cut for a variety of reasons. Additionally, these
ducts or tissues may need to be closed and separated. In some
cases, these ducts or tissues are the reason or part of the reason
for surgery, such as tubal ligation, gall bladder removal, or
resecting tissue of an organ, etc. Thus, a surgeon may clamp, block
and/or cut ducts or tissue(s) in a variety of situations.
[0004] Separating ducts or sealing and cutting tissue can take time
and require multiple instruments. Sometimes multiple instruments
may be needed for each step during a surgical procedure. In the
case of blood, if the surgeon does not adequately clamp, block and
cut and tie-off or otherwise seal the blood vessels or other ducts
or tissue, blood or other body fluids may leak. This may cause the
unfortunate effect of obfuscating the surgical area and create
other concerns such as causing blood coagulation and build-up on a
surgical instrument. More importantly, the loss of blood can
endanger the patient's life. A large bleeder can quickly cause
death and even a small bleeder can cause significant injury or
death over time. Likewise, the leaking of some body fluids may
contaminate the area being operated on.
[0005] Cutting and sealing or tying off a blood vessel can be a
cumbersome process. If a doctor desires to cut a major vessel, he
or she will typically clamp both sides of where the cut is to be
made. Once each side is clamped, the incision is made and the ends
are either tied off or are sealed to prevent blood loss through the
vessel after the incision. In a surgery involving many blood
vessels, it can be time consuming and tiring to properly clamp, cut
and tie off or seal each vessel. This is particularly so if the
surgeon has to cut out or cut through tissue. Thus, there is a need
for an instrument that can simply cut tissue, ducts, etc. while
preventing leakage from any ducts. Additionally, there is a need
for an improved method of clamping, cutting and sealing a duct or
tissue in a human or animal body.
[0006] Another consideration in sealing and cutting ducts or
tissues is ensuring that the sealing and cutting is done generally
consistently across the duct or tissue. If the sealing and cutting
is done with a scissor-like instrument, more sealing may be applied
on one side of the duct or tissue (i.e. the portion closest to the
hinge of the surgical instrument) than on the opposing side because
more force is applied adjacent the hinge. Thus, it is believed that
it would be preferable to have surfaces which are used to seal and
cut ducts or tissue to engage the tissue generally parallel to one
another, thereby providing a more consistent seal.
SUMMARY OF THE INVENTION
[0007] It is an object of the present invention to provide an
improved tissue cutting and sealing instrument.
[0008] In accordance with the present invention, a surgical
instrument is provided with at least one active surface or
thermally active element mechanism which has at least one element
such that a portion of the active surface or thermally active
element mechanism can be heated to a temperature which seals tissue
and a portion of the active surface can be heated to a temperature
which cuts tissue to thereby allow tissue to be both sealed and cut
by the same device.
[0009] According to one aspect of the invention, two different
energy settings may be sent to a thermally active element to seal
and then cut tissue. (As used herein thermally active element and
active element may be used interchangeably to reference an element
which is heated to treat, e.g. seal or cut tissue). Thus, a
physician may attach the instrument to a duct or tissue being cut,
seal the duct or tissue to prevent leakage and then cut the duct or
tissue between sealed portions to disconnect the two parts of the
duct or tissue. Sealing the duct prior to or concurrent with
cutting it prevents the contents of the duct or tissue from leaking
into a patient's body. This is particularly important when dealing
with ducts which carry potentially harmful materials like bile or
fecal matter. Thus, in accordance with one aspect of the invention,
an instrument is provided which seals and then cuts a duct. This
may be accomplished by a single grasp of the duct, with the active
element mechanism applying a first, sealing heat and a second,
cutting heat to seal and then cut the duct.
[0010] In accordance with another aspect of the invention, a single
active element may seal and cut the duct with the application of
heat of sufficient duration to first seal and then cut the
duct.
[0011] In accordance with another aspect of the invention, more
than one active element may be used. If two elements or more are
used, a first element (e.g. an outer element) may seal the duct or
tissue first, while a second element (e.g. an inner element) may
cut the duct or tissue after it has been sealed, thereby leaving at
least a portion of the sealed duct or tissue on either side of the
cut.
[0012] According to another aspect of the invention, the system may
monitor indicators, such as temperature, standing wave ratio
("SWR"), etc. of the active element, or the temperature, electrical
impedance, capacitance, conductance, moisture content, etc. in the
tissue or contents of the duct, to determine when sealing and/or
cutting has been adequately applied.
[0013] In accordance with another aspect of the present invention,
the elements may be configured for sealing and cutting a duct or
other tissue on one side, i.e. cutting a piece of tissue off, or
from two or more sides, such as cleaving a piece of tissue along a
plane.
[0014] According to another aspect of the invention, one or more
active elements are disposed on a surgical sealing and cutting
instrument which has two treatment surfaces which are disposed
generally parallel to each other and remain generally parallel to
one another while treatment surfaces are moved into engagement with
a duct or tissue to be sealed and/or cut to thereby provide a more
consistent seal.
[0015] In accordance with another aspect of the present invention,
the system may use a parallel surface movement linkage, such as a
pantograph linkage to generally equally engage a duct or tissue and
to generally equally apply heat and pressure to tissue to ensure
adequate and even sealing and cutting has been performed.
[0016] These and other aspects of the present invention are
realized in a tissue cutting and sealing instrument as shown and
described in the following figures and related description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Various embodiments of the present invention are shown and
described in reference to the numbered drawings wherein:
[0018] FIG. 1 shows a perspective view of a surgical sealing and/or
cutting system;
[0019] FIG. 2 shows a close-up, fragmented view of a single element
tip of a surgical sealing and/or cutting instrument;
[0020] FIG. 3 shows a close-up, fragmented view of a double element
tip of a surgical sealing instrument;
[0021] FIG. 4 shows a close-up, fragmented view of a surgical
sealing instrument showing a sealing barrier;
[0022] FIG. 5 shows a close-up, fragmented view of a surgical
sealing instrument with two sealing elements in an alternate
configuration;
[0023] FIG. 6 shows a close-up, fragmented view of a surgical
sealing instrument with three elements in a configuration similar
to that of FIG. 5;
[0024] FIG. 7 shows a close-up, fragmented view of the active
surface of a surgical sealing instrument with four elements in a
configuration similar to that of FIG. 6;
[0025] FIG. 8A shows a fragmented, cross-sectional view of an
alternate configuration for the tip of a surgical sealing
instrument according to principles of the present invention;
[0026] FIG. 8B shows a close close-up, fragmented view of the
active surface of the surgical sealing instrument shown in FIG.
8A;
[0027] FIG. 8C shows a fragmented, side cross-sectional view of an
another alternate configuration for the tip of a surgical sealing
instrument according to principles of the present invention;
[0028] FIG. 8D shows an end cross-sectional view of the tip of the
surgical sealing instrument of FIG. 8C.
[0029] FIGS. 8E through 8P show end views of alternate
configurations of active elements structures which may be used on
tips of a surgical sealing and/or cutting instrument according to
principles of the present invention;
[0030] FIG. 9 shows a close-up, fragmented view of yet another
alternate configuration of the tips of a surgical sealing
instrument;
[0031] FIG. 10A shows a close-up, fragmented view of a tip of a
surgical sealing instrument having a heat dispersing element;
[0032] FIG. 10B shows an end view of the tip of FIG. 10A;
[0033] FIG. 11 shows a close-up, fragmented view of an alternate
tip of a surgical sealing instrument;
[0034] FIG. 12 shows a fragmented, side view of another tip of a
surgical sealing instrument according to principles of the present
invention;
[0035] FIG. 13 shows a fragmented, top view of the tip of FIG.
12;
[0036] FIG. 14 shows a fragmented, side view of the tips of a
surgical sealing instrument;
[0037] FIG. 15 shows a perspective view of a surgical instrument
having cooperating elements;
[0038] FIG. 16 shows a perspective view of another surgical
instrument made in accordance with the present invention;
[0039] FIG. 17 shows a perspective view of another surgical
instrument having cooperating elements
[0040] FIGS. 18 and 19 show surgical instruments being used on
tissue in accordance with the present invention;
[0041] FIG. 20 shows a close-up, side view of the parallel movement
surgical sealing and cutting tool in a nearly closed position;
[0042] FIG. 21 shows a side view of the parallel movement surgical
sealing and cutting tool of in an open position;
[0043] FIG. 22 shows a side, fragmented view of a parallel movement
surgical sealing and cutting tool operable through a catheter or
cannula with pistol grip, the sealing tool being in an open
position;
[0044] FIG. 23 shows the surgical sealing and cutting tool of FIG.
22 in a closed position;
[0045] FIG. 24 shows a side, plan view of the surgical sealing and
cutting tool of FIG. 22;
[0046] FIG. 25 shows a close-up, side view of a parallel movement
end for a surgical sealing and cutting tool;
[0047] FIG. 26 shows a parallel movement surgical sealing and
cutting tool with finger rings;
[0048] FIG. 27 shows a parallel movement surgical sealing and
cutting tool with a squeeze grip;
[0049] FIG. 28 shows a side view of an alternate embodiment of a
surgical instrument made in accordance with principles of the
present invention; and
[0050] FIG. 29 shows a chart correlating estimated tissue effects
with temperature.
[0051] It will be appreciated that the drawings are illustrative
and not limiting of the scope of the invention which is defined by
the appended claims. The embodiments shown accomplish various
aspects and objects of the invention. It is appreciated that it is
not possible to clearly show each element and aspect of the
invention in a single figure, and as such, multiple figures are
presented to separately illustrate the various details of the
invention in greater clarity. Similarly, not every embodiment need
accomplish all advantages of the present invention.
DETAILED DESCRIPTION
[0052] The invention and accompanying drawings will now be
discussed in reference to the numerals provided therein so as to
enable one skilled in the art to practice the present invention.
The drawings and descriptions are exemplary of various aspects of
the invention and are not intended to narrow the scope of the
appended claims. Furthermore, it will be appreciated that the
drawings may show aspects of the invention in isolation and the
structures in one figure may be used in conjunction with structures
shown in other figures.
[0053] Tissue sealing may be used to construct a barrier between
two or more portions of tissue or duct, or may be used to repair
damaged tissue. In many cases, the tissue or duct may provide a
pathway for delivery of material, such as eggs in a fallopian tube
or blood in a blood vessel. A barrier may thus prevent functional
operation, in the case of the fallopian tube, or even prevent
leakage, such as in the case of the blood vessel. The barrier may
also prevent contamination, by closing a potential entrance or exit
for contaminants. In some cases, it may be desirable to cut the
tissue apart after sealing. Each portion of separated tissue may
retain some of the seal. Thus, the tissue seal may act as a barrier
to prevent contents of the tissue exiting and/or other contaminants
entering the cut tissue. Likewise, tissue having an open wound or
otherwise needing to be sealed off can be sealed to close the wound
and prevent entry of contaminants or to prevent exit of material
from the tissue.
[0054] For example, tissue sealing and cutting may be used for
tubal ligation. A fallopian tube may be sealed and then cut. By
sealing the fallopian tube, eggs may be prevented from navigating
the fallopian tubes and entering the uterus. However, to ensure
that the flow of an egg into the uterus is not possible, the sealed
tube is ligated as well. Similarly, blood vessels may be sealed to
stop blood flow prior to being cut to prevent bleeding during and
immediately after the cut. As will be explained below,
ferromagnetic covered conductors may provide advantages in sealing
and cutting ducts and other tissues, including reduced cost,
simplicity of operation and increased effectiveness in tissue
sealing and cutting instruments.
[0055] In FIGS. 1 to 19, there are shown tissue sealing and cutting
instruments in accordance with one aspect of the present invention.
In FIGS. 20 to 28, there are shown surgical instruments in
accordance with another aspect of the present invention, and which
may be used in conjunction with the tissue sealing and cutting
instruments discussed in FIGS. 1 to 19. Parallel surface movement
may include a ferromagnetic covered conductor based tissue sealing
and cutting instrument described in FIGS. 1 to 19, along with other
sealing and cutting technologies. In FIG. 29, a chart of estimated
temperature correlation to tissue effects is shown.
[0056] Turning now specifically to FIG. 1, a perspective view of a
handheld sealing and cutting instrument 10 and system 15 is shown.
Many surgical procedures require cutting or ligating ducts, such as
blood vessels, or other vascular tissue. Due to the inherent
spatial considerations of the surgical cavity, surgeons often have
difficulty suturing vessels or performing other traditional methods
of controlling bleeding, e.g., clamping and/or tying-off transected
blood vessels. By utilizing a surgical sealing and/or cutting
instrument 10, a surgeon can cauterize, coagulate/desiccate and/or
simply reduce or slow bleeding.
[0057] For treating larger vessels, a surgeon may opt to seal the
tissue or vessel. Tissue sealing is fundamentally different than
simply coagulating or cauterizing vessels. For the purposes herein,
"coagulation" is defined as a process of desiccating tissue wherein
the tissue cells are ruptured and dried. "Duct sealing", "vessel
sealing" or "tissue sealing" is defined as the process of
liquefying the collagen in the duct, vessel, tissue, etc. so that
it reforms into a fused mass with limited demarcation between
adjacent tissue structures. In order to effectively seal larger
ducts (or tissue) two predominant parameters must be accurately
controlled--the pressure applied to the duct or tissue and the
amount of heat which is conducted from the tip 20A and/or tip 20B
to the duct or tissue.
[0058] It will be appreciated that the surgical sealing and cutting
instrument 10 varies from many prior art electrosurgical tools in
that in the instrument of the present invention heat is generated
directly in an active element 110 located on tip 20A and/or 20B.
This is in contrast to many electrosurgical instruments, such as
bipolar or monopolar instruments, which use one or more probes to
direct electrical current into tissue where the resistance to the
electrical current generates heat in the tissue rather than at a
thermal element. In other words, a thermal instrument generates
heat and applies the heat to the tissue, while monopolar and
bipolar devices pass electricity into the tissue which results in
heat being developed in the tissue.
[0059] In use the sealing and/or cutting instrument 10 has tips
20A, 20B which may be placed around or on opposing sides of a duct
or tissue to be sealed. The tips 20A and 20B may be placed at the
end of arms 30A, 30B which are held in a user's hand. A user may
squeeze the arms 30A, 30B of the instrument together causing the
tips 20A, 20B to provide pressure on the duct or tissue. Electrical
energy may then be directed to an active element 120 on the active
surface 40 of tip 20A and/or 20B to heat the thermally active
element 120. (It will be appreciated that the active element could
be applied hot to the duct, or could by applied and then heated).
The heat generated in the active element is applied to the duct or
tissue to cause the duct or tissue to seal. In accordance with one
aspect of the invention, a second energy level may be applied to
the active element 110 (or a separate active element) to heat the
active element 110 to a second temperature that is sufficient to
cut the duct or tissue apart. This may be accomplished using one
element 110 or by separate elements 110, 120. Power may be received
by the instrument 10 through a cable 50.
[0060] Alternatively, electrical energy may be delivered to one or
more active elements, such as active elements 110, 120,
substantially simultaneously to seal and cut the duct or tissue.
Under such circumstances, active element 110 may be configured to
provide a higher thermal density as compared to the thermal density
provided by active element 120. (As used herein "thermal density"
means the rate at which thermal energy is conducted into a duct or
tissue.) Thus, the process of sealing and cutting a duct or tissue
can be initiated substantially simultaneously, rather than
sequentially, to reduce the amount of time it would take a surgeon
to seal and cut the duct or tissue. As explained in more detail
below, it will be appreciated that a single active element having a
surface may be shaped to provide a higher thermal density to the
duct or tissue at a particular location along the surface. Thus, a
single active element may be used to both seal and cut a duct or
tissue according to principles of the present invention.
[0061] According to one aspect of the invention, the active element
110 (and/or active element 120) may be formed by a conductor having
a ferromagnetic coating to form a thermally active element. As used
herein, the term "ferromagnetic," "ferromagnet," and
"ferromagnetism" refers to any ferromagnetic-like material that is
capable of producing heat via magnetic induction, including but not
limited to ferromagnets and ferrimagnets. It is not intended that
such materials must be heated exclusively by magnetic induction
unless otherwise indicated and such may acquire heat from resistive
heating, eddy currents, etc., in addition to magnetic induction.
Power, such as a radio frequency (RF) waveform, may be provided to
the conductor. The RF energy may travel along the conductor's
surface in a manner known as the "skin effect". The current density
is generally greatest at the surface and decreases in magnitude
further into the material where the electric field approaches zero.
The depth at which the skin effect current is reduced to about 37
percent of its surface value is referred to as the skin depth and
is a function of the electrical resistivity, the magnetic
permeability of the material conducting the current, and the
frequency of the applied alternating RF current.
[0062] The alternating RF current in the conductor's surface
produces an alternating magnetic field, which may excite the
domains in the ferromagnetic portion 65. As the domains realign
with each oscillation of the current, hysteresis losses in the
coating may cause inductive heating. Heating of the ferromagnetic
portion 65 due to hysteresis loss ceases above the Curie point
because the material loses its magnetic properties.
[0063] According to one aspect of the invention, the ferromagnetic
coating may have a thickness of approximately 4 to 5 skin depths.
As the power passes through the conductor, heat is produced in the
ferromagnetic material. For the purposes herein, the heat produced
in the ferromagnetic material may be referred to as "ferromagnetic
heat" or "ferromagnetic heating" and includes heat produced by
magnetic induction or related mechanisms caused by delivering
electrical energy from a power source to a ferromagnetic coated
conductor in a closed circuit. As explained above, heat may also be
generated in the ferromagnetic material due to resistive heating,
eddy currents, etc., however, ferromagnetic heat and ferromagnetic
heating excludes heat generated by an electrosurgical element that
is used to direct electrical energy into tissue to cause heating of
the tissue directly, such as a bipolar or monopolar instrument.
Thus, it is anticipated that the principle source of heat will be
current passing through the thermally active element rather than
current passing through tissue adjacent thereto.
[0064] When the ferromagnetic coating is thin relative to the
conductor, the ferromagnetic coating can quickly heat to
temperatures which will seal and/or cut tissue, and then rapidly
cool to a temperature where the ferromagnetic coating will not even
burn the skin within a very short time period. For example, a
tungsten conductor having a diameter of about 0.375 mm and a
ferromagnetic coating of a Nickel Iron alloy (such as NIRON.TM.
available from Enthone, Inc. of West Haven, Conn.) about the
tungsten conductor about 0.0375 mm thick can be used as the
element. Multiple different frequencies can be used, including
frequencies from 5 megahertz to 24 gigahertz. Further, a
ferromagnetic covered conductor may be comprised of a ferromagnetic
material generally surrounding an electrical conductor (either
touching or not touching the conductor), and which produces heat
when electrical energy is supplied to the conductor. A more
detailed discussion of powering ferromagnetic coated/covered
conductors to generate heat sufficient to seal and/or cut through
tissue is described in more detail in U.S. Publication No.
US-2010-0268207-A1 and US-2010-0268210-A1, which are expressly
incorporated herein in their entirety. It will be appreciated that
improved heat may be obtained by a ferromagnetic coating which
completely circumscribes the conductor along the portion desired to
be heated.
[0065] Energy may be provided by a power supply 60 through the
cable 50 to the handheld sealing and/or cutting instrument 10. The
energy may be, for example, an oscillating current, such as an
alternating RF signal. The power supply may include settings 70,
displays 80 and one or more cables, such as cable 50. The current
power setting may be controlled by a switch 90 on the forceps or
foot pedal 100 connected to the power supply by a cable or through
wireless communication. Current may be passed from the power supply
60, through the cable 50, through the instrument 10 and along the
conductor through the ferromagnetic portion and back to the power
supply with the vast majority of the current staying in the
conductive pathway of the tool rather than being transmitted
through tissue.
[0066] The handheld sealing and/or cutting instrument 10 may have
one or more active surfaces 40. In one embodiment, the active
surface is only on tip 20A. In another embodiment, an active
surface may be on both tips 20A and 20B. For example, tip 20B may
be a mirror image of tip 20A. A single active surface 40 may be
desirable and cost efficient for smaller ducts or tissues to be
sealed. Multiple active surfaces may be desirable for work on
larger tissues, as the heat may be more consistently presented to
the tissue.
[0067] The active surface 40 may include one or more active element
110, 120. The active element may be embedded in a layer of material
at the active surface 40 or may extend outwardly from or located
adjacent to the active surface 40 so that it is positioned away
from the surface of the forceps tips 20A, 20B. Thus, the elements
110, 120 may be configured to seal and/or cut when the surface 40
touches tissue, or may seal or cut prior to the surface 40 engaging
the tissue. Moreover, the element(s) 110, 120 may themselves be the
surface which engages the tissue.
[0068] It will be appreciated that the active element(s) 110, 120
on each of the tips 20A and 20B may be activated at the same time,
or one or both may be operated separately. Thus, for example, if a
surgeon needs to seal a small vessel or other duct, he or she may
activate sealing tip 20A or 20B and then activate both when
encountering a larger vessel or duct.
[0069] Turning now to FIG. 2, a close-up view of a single element
tip, such as tip 20A, of a handheld sealing instrument is shown. In
one embodiment, tip 20A may include an active surface 40 with a
single active element 110, which may be loop or shaped as an
elongated arch, i.e. an arch with two arms extending from the
curved portion. The active element 110 may be a material which will
heat sufficiently to seal and/or cut human or animal ducts or
tissue. The active element 110 may be, for example, a conductor 104
forming a closed circuit with a power source and having a
ferromagnetic coating 114 disposed on the conductor. The single
active element 110 may be able to function with at least two energy
settings: a setting for sealing tissue together and a setting for
cutting through tissue.
[0070] For example, a surgeon may use pressure to apply the active
surface 40 to a blood vessel or other duct. This may include the
blood vessel being disposed across the arms of the active element
extending from the art. The surgeon may then control power
delivered to the ferromagnetic covered conductor forming the active
element 110 by activating a first power setting causing the blood
vessel or other duct to seal or weld closed, at two locations
depending on the distance between the arms. If needed, the surgeon
may repeat the sealing on adjacent blood vessel tissue to provide a
wider seal. The surgeon may then place the active surface 40 in the
middle of the sealed tissue (or leave the active surface 40 where
it is, if the surgeon did not move it). The surgeon may activate a
second power setting to cause a portion of the sealed blood vessel
or other duct to be cut with heat generated in the ferromagnetic
coating of the active element 110. Thus the blood vessel or other
duct may be sealed closed from contamination and/or leakage while
being separated into two parts (or being sealed before being cut
and then having the open end cut off distal to the seal). It will
be appreciated that there are several ways for controlling whether
sealing or cutting heat is applied, such as by regulating the duty
cycle to control the amount of heat being generated in the
ferromagnetic coating 114.
[0071] Turning now to FIG. 3, a side view of a double active
element tip of a handheld sealing instrument is shown. In one
embodiment, a tip 20A may include an active surface 40 with two
active elements 110, 120 which are controlled together or
separately, or by two active sub-elements 130A, 130B (i.e. two
portions of a common element) which may be controlled together,
such as a pair of ferromagnetic covered conductors. For ease of
reference, the conductors may be referred to as separate elements
110, 120 regardless of whether a single element with two parts or
two separate elements etc., is used, unless specifically designated
as one or the other. Examples of sub-elements, as the term is used
herein, may include an active element comprising a conductor having
a plurality of spaced apart ferromagnetic coatings thereon, an
active element comprising a conductor having a first coating of a
first ferromagnetic material and a second coating of a second
ferromagnetic material different than the first ferromagnetic
material, etc. It will be further appreciated that while two
elements or sub-elements are shown, an active surface 40 having a
larger number of elements or sub-elements may be used for a variety
of purposes.
[0072] The active element(s) 110, 120 may use a separate power
setting for each sub-element 130A, 130B or conductor 104. The outer
sub-element 130A or element 120 may be configured for a sealing
temperature range, such as a temperature range sufficient to heat
the tissue to about 58.degree. C. to 200.degree. C. or more
preferably 58.degree. C. to 62.degree. C. The inner element 130B or
element 110 may be configured for a cutting temperature, such as a
temperature range sufficient to heat the tissue to about
200.degree. C. to 500.degree. C., or more preferably 200.degree. C.
to 400.degree. C. By using an outer sub-element 130A or element 120
to seal and an inner sub-element 130B or element 110 to cut, the
inner element/sub-element may avoid cutting the sealed portions of
a duct or vessel by cutting in between the seals. (It will be
appreciated that inner and outer are used for convenience only and
are not intended to limit the geometry of the active elements 110,
120.) When a sealing element and a cutting element are used, the
sealing element may be above, below, on either side or any other
position relative to the cutting element which is desired by the
surgeon. The result of a duct being disposed across the active
elements 110, 120 will be two seals and two cuts between the seals,
thus clearly terminating flow through the duct and sealing the duct
adjacent the cut which minimizes the risk of accidentally cutting
through the seal.
[0073] Elements 110 and 120 are shown as having a generally loop or
curve-shape end with arms extending therefrom. Additionally, the
thermally active elements 110, 120 are shown as being generally
parallel to one another. This allows the element 100,120 to be
placed on a duct with the length of the loop generally
perpendicular to the duct with the outer element 120 sealing the
duct and the inner element 110 cutting the duct to remove a small
segment and leave sealed segments on either site of the cuts. It
will also be appreciated that in certain surgeries, different
configurations may be desirable depending on the orientation of the
ducts which are to be sealed. Any such geometries are intended to
be covered by the claims unless specifically limited therein.)
[0074] For example, a surgeon may use pressure to apply the active
surface 40 to a blood vessel. The surgeon may then cause the outer
element 120, which may be a ferromagnetic covered or coated
conductor, to receive a first power setting causing the blood
vessel to seal or weld closed. The surgeon may then activate a
second power setting to the inner element 110, which may be a
ferromagnetic covered or coated conductor, causing an inner portion
of the sealed blood vessel to be cut out of the blood vessel. The
same procedure may be used with other ducts as well.
[0075] It will be appreciated that the active surface may be used
both to cut an intact duct, for example to both seal and cut a
fallopian tube, or to seal and then cut off the end of a duct which
has already been cut, such as sealing off a severed blood vessel
and then cutting off the excess vessel beyond the seal, if
necessary. Thus the blood vessel may be sealed closed from
contamination and/or leakage while being separated into two parts
or cleaned up after being cut, if necessary.
[0076] Turning now to FIG. 4, a side view of a sealing barrier
distance 140 of a handheld sealing instrument is shown. The sealing
barrier distance 140 between the outer sub-element 130A (or element
120) and inner sub-element 130B (or element 110) may determine the
amount of sealed tissue remaining on each side of a cut performed
by the inner sub-element 130B. Depending on the tissue, the sealing
barrier distance 140 may be adjusted. This may be done by selecting
forceps 10 (FIG. 1) with tips 20A or 20b having sub-elements 130A
and 130B at a desired distance, by having one of the sub-elements
be adjustable, or by having forceps with one tip 20A having a first
distance between the sub-elements, and the other tip 20B having a
different distance between the sub-elements so that the surgeon can
choose which tip to use.
[0077] According to one aspect of the invention, the distance may
be adjusted as the outer and/or inner active elements may be
malleable. A tip linkage may move the outer and/or inner active
elements to increase or decrease distance between the outer and
inner active elements.
[0078] Active elements may include multiple different technologies.
In some cases, two technologies may be combined. For example, a
bipolar element may be used as the outer sealing element, while a
ferromagnetic covered conductor may be used to cut the tissue as an
inner element, or vice versa. Ferromagnetic covered conductors may
be desirable for many applications because of their ability to
quickly heat and cool, as well as the small amount of tissue damage
beyond the point of contact. In one embodiment the ferromagnetic
coating circumscribes the conductor to facilitate inductive
heating.
[0079] The system may also incorporate sensors to aid in the
determination of appropriate sealing times and cutting application
times. The system may monitor the temperature, standing wave ratio
("SWR"), etc. of each active element, or the temperature,
conductivity, moisture content, or impedance or some combination
thereof, of the tissue. In one embodiment, the system automatically
seals and then cuts the tissue when the surgeon applies the
instrument to tissue and activates the instrument. This could be
done, for example, by monitoring the moisture content of the
tissue. During the sealing step, the tissue will lose moisture
content to a point, at which cutting will begin. Thus, moisture
content passing beyond a desired threshold can be used to raise an
indicia that sealing is complete and cutting has or will begin.
[0080] Likewise, the system may monitor temperature over time
(using, for example, a sensor as shown in FIG. 17) and determine
when appropriate sealing has been completed before the cut energy
is applied. This can be done by monitoring the temperature of the
element which will tend to stay near a fixed temperature until
sealing is complete, and then suddenly rise as it cuts.
Alternatively, the system may monitor may monitor the temperature,
electrical properties, or some other characteristic, of the tissue
or duct, using a sensor (see e.g. FIG. 17) located on one or both
of the tips 20A and 20B. Thus, the temperature, electrical
properties, etc. of the tissue or duct can be monitored across
from, or adjacent to, the sealing and/or cutting elements.
According to one aspect of the invention, a light or sound may be
emitted from the instrument or power supply to notify the surgeon
when a phase appears to be completed. Thus, the surgeon may listen
for a first sound or see a first light to know that a sealing phase
is completed. The surgeon may then activate the cutting phase and
await a second light or sound to know that the cutting phase is
completed and the instrument may be removed, or the instrument may
automatically perform each step and provide notification when each
is complete.
[0081] During a procedure, power delivery to the sealing instrument
10 may be controlled by varying the amplitude, frequency or duty
cycle of the alternating current waveform, or alteration of the
circuit to affect the standing wave driving the ferromagnetic
coated conductor.
[0082] Turning now to FIG. 5, there is shown an alternate
arrangement of an active surface 40. In FIGS. 1-4, the active
element(s) 110, 120 were generally U-shaped as may be beneficial
for sealing and cutting out a portion of a duct. There are
situations, however, where it is desirable to cut off or cut out a
portion of tissue or a duct which involves sealing and cutting
tissue over an elongate area. Thus, rather than using an active
surface 40 having U-shaped active element(s) 110, 120, FIG. 5 shows
active elements which may be generally linear and generally
parallel and which may be used in a manner somewhat analogous to
use of a pair of scissors. (As explained in more detail below, the
active element(s) 110, 120 shown in FIGS. 5-7 may be formed from a
flattened conductor 104 covered by a ferromagnetic coating 114.) If
desired one or both conductors 104 and/or the coatings may be
flattened.
[0083] As shown in FIG. 5, one element 120 may be used for sealing,
while another element 110 may be used for cutting. Thus, a surgeon
or other user would engage the tissue and activate the sealing
element 120 and the cutting element 110. This may be done
simultaneously or sequentially depending on the time necessary for
the sealing element 120 to adequately seal off fluid flow through
the tissue. By advancing the active surface 40 along the tissue,
and activating the active elements 110 and 120, the tissue on the
side of element 110 opposite element 120 would be cut off.
[0084] While reference is made to an active surface 40, it will be
appreciated that the active element may be in the active surface or
extend outwardly from the active surface depending on the intended
use and the desires of the user. Thus, it will be appreciated that
active surface 40 itself need not seal or cut tissue.
[0085] Turning to FIG. 6, there is shown an alternate configuration
of an active surface 40. The active surface 40 may include two
sealing active elements 120 and a cutting active element 110
disposed therebetween. (As used herein, a sealing active element is
a thermally active element which is heated to seal tissue and a
cutting active element is a thermally active element heated
sufficiently to cut tissue. It will be appreciated that one element
could function as both depending on how it is controlled.)
[0086] In use the active surface 40 may be placed along a tissue to
be cut. The sealing active elements 120 may be used to seal the
tissue on either side of the cutting active element 110 and the
cutting active element used to cut the tissue to ensure that flow
between opposing sides does not continue. Thus, for example, if
flow through a duct needed to be prevented, the duct will be sealed
on either side of the cut, thereby ensuring both sealing and
cutting of the duct.
[0087] Turning now to FIG. 7, there is shown yet another
configuration of an active surface 40. The active surface 40 may
include two sealing active elements 120 which are spaced apart and
two cutting active elements 110 which are spaced apart a desired
distance 126. In use the active surface can be placed on a tissue
or duct to be cut (with the length generally perpendicular to the
length of the duct) and the active elements 110, 120 energized to
seal and cut the tissue or duct. In addition to sealing and/or
cutting the tissue or duct, the arrangement of the cutting active
elements 110 will cut out a strip of the tissue or duct. This may
be desirable when the active elements are being used to remove a
diseased portion of tissue, or where is it desirable to remove a
segment of a duct to ensure that flow therethrough has been
terminated. For example, in tubal ligation, it is often required to
affirmatively remove a section of the fallopian tube to ensure that
there is no risk of pregnancy in the future. With the active
surface of FIG. 7, both sides of the cut will be sealed and a
segment between the cuts can be removed for adequate reassurance
that flow through the fallopian tube is no longer possible.
[0088] Turning now to FIGS. 8A and 8B, there is shown an alternate
configuration for the tip, generally indicated at 20A, of a
surgical sealing instrument according to principles of the present
invention. Similar to the tips described above, the tip 20A may
include a thermally active element 110 comprised of a conductor 104
having a ferromagnetic coating 114 disposed thereabout to form a
ferromagnetic heating region. The active element 110, however, may
form a generally flat, planar surface. The generally planar surface
of the active element may be formed by flattening a section of a
conductor wire 104 and plating a coating of ferromagnetic material
114 on the flattened conductor 104 such that the ferromagnetic
coating 114 substantially covers the entire outer surface of a
length of the flattened conductor 104. (The coating 114 may extend
completely around the conductor 104 if desired). The flattened
conductor 104 may form a closed circuit with a power source
directly or via intervening conductors such that applying
electrical energy across the flattened conductor causes substantial
uniform ferromagnetic heating along the ferromagnetic region of the
active element 110.
[0089] The flattened conductor may extend along an arm 30A of a
sealing and/or cutting instrument of the present invention, such
that electrical energy supplied from a power source travels towards
the ferromagnetic material 114 through section 104a of the
conductor 104, away from the ferromagnetic material 114 through
section 104b of the conductor 104, and back to the power supply.
(It will be appreciated that, alternatively, electrical energy
could travel towards the ferromagnetic material 114 through section
104b and away from the conductor through section 104a). Arm 30A may
include a thermally and/or electrically isolating material 106 to
substantially prevent transfer of heat and/or electrical current to
the arm 30A of the surgical sealing and/or cutting instrument.
Additionally, an electrically isolating material 116 may be
disposed between sections 104a, 104b of the conductor 104 to
prevent current from bypassing the ferromagnetic material.
[0090] As will be appreciated, the active element 110 shown in
FIGS. 8A and 8B will have a larger surface area for contacting a
duct or tissue to be sealed and/or cut. By applying heat to a duct
or tissue using an active element 110 with a larger surface area a
better seal may be created along the duct or tissue.
[0091] Turning now to FIG. 8C, there is shown a fragmented, side
cross-sectional view of another configuration for tips of a
surgical sealing and/or cutting instrument according to principles
of the present invention. For clarity purposes, the cross-hatching
of the active elements 110, 120 has been removed. FIG. 8D shows an
end, cross-sectional view of the thermally active elements of FIG.
8C. The tips 20A, 20B may include active element(s) 110, 120. Each
active element 110, 120 may comprise a conductor 104 having a
ferromagnetic coating 114 disposed thereon, similar to the active
element shown in FIGS. 8A and 8B. However, it will be appreciated
that only one active element need generate thermal energy which is
conducted to a duct or tissue according to principles of the
present invention as explained in more detail below. As best shown
in FIG. 8D, the active element 110 may be formed such that there is
a cutting zone 115, formed by a protrusion, rib, etc., and a
sealing zone 103 in the ferromagnetic heating region. As shown in
FIG. 8D the cutting zone 115 is a protrusion which extends away
from the generally planar surface which forms the sealing zone 103
of the active element. When a surgeon squeezes the arms 30A, 30B of
the instrument together to cause the active elements 110,120 to
contact the duct or tissue, an increased amount of pressure will be
applied to the duct or tissue at the location of the protrusion of
the cutting zone 115. Heat generated by active elements 110, 120 is
conducted to the duct or tissue, with a higher thermal density at
the location of the cutting zone 115. Thus, a better seal may be
achieved at the location of the cutting zone 115, or the duct or
tissue may be severed along the cutting zone 115 due to the
increased amount of pressure while areas of the duct or tissue in
the sealing zone 103 may be sealed.
[0092] As explained above, a higher thermal density is required to
cut a duct or tissue as compared to sealing the duct or tissue. To
increase the thermal density along the cutting zone 115 the
pressure applied and/or the heat conducted to the duct or tissue at
the location of the cutting zone must be increased. Thus, as shown
in FIG. 8D, the protrusion may provide increased pressure applied
to the duct or tissue at the location of the cutting zone 115,
thereby allowing the duct or tissue to be cut along the cutting
zone 115 while being sealed along sealing zones 103. Thus, a single
application can be used to both cut and seal.
[0093] Active elements may be constructed to have a variety of
shapes in order to create a cutting zone and sealing zone similar
to the cutting zone 115 and 103 discussed in connection with FIG.
8C. For example, FIGS. 8E through 8P show various active elements
having different shapes or elements which may be used to create a
cutting zone and sealing zone. These active elements could be used
in conjunction with forceps or other thermally active surgical
instruments shown herein.
[0094] It will be appreciated that the scope of the invention is
not to be limited by the embodiments shown in FIGS. 8E through 8P,
rather, FIGS. 8E through 8P are being provided for illustrative
purposes only. Furthermore, for clarity, FIGS. 8E through 8P only
show the active elements 110, 120, but it will be understood that
the other elements of a sealing and/or cutting instrument according
to principles of the present invention disclosed herein (e.g. the
sealing and/or cutting instrument of FIG. 8C) would be associated
with the active elements 110, 120 shown in FIGS. 8E through 8P.
[0095] While FIG. 8E shows an active element 110 (similar to the
active element 110 shown in FIG. 8B) having a ridge extending along
the planar surface of the upper active element 110 to form the
cutting zone 115 and sealing zones 103 adjacent to the cutting zone
115, the projection forming the cutting zone 115 could be on the
lower active element 120. (It will be appreciated that elements 110
and 120 as shown in FIGS. 8A-8P can function both as a cutting
element and a sealing element or portions thereof.
[0096] According to one aspect of the invention the structure shown
as element 120 may not be a ferromagnetic coated conductor. In
fact, the structure 120 may only be a support structure (e.g. not a
thermal element) which provides a compressive surface opposite
active element 110. Alternatively, the active element 120 may
generate heat to seal and/or cut a duct or tissue and have a ridge
forming a cutting zone 115, while the active element 110 is a
support structure for use as a compressive surface opposite active
element 120 as shown in FIG. 8F.
[0097] FIG. 8G shows and active element 110 similar to that shown
in FIG. 8E. The active element 120, however, differs from the
active element 120 shown in FIG. 8E in that the active element 120
of FIG. 8G comprises a recess 117, or quasi-complimentary
receptacle, to alter the compression force applied to a duct or
tissue when the active elements 110 and 120 are squeezed together
to engage the duct or tissue.
[0098] FIG. 8H shows and active element 120 with a sharp cutting
zone 115 to facilitate cutting of a duct or tissue. The compressive
force applied to a duct or tissue along the cutting zone 115 may be
altered by including a recess 117 on active element 110 positioned
generally opposite the cutting zone 115. While not shown in the
drawings for brevity, the active element 110 of FIG. 8G could be
combined with the active element 120 of FIG. 8H to form protrusions
in alignment or out of alignment with one another to provide a
desired cutting dynamic.
[0099] FIGS. 8I and 8J show an arcuate active element 110 and an
arcuate active element 120, respectively. A cutting zone 115 may be
formed about the apex of the curved or arcuate active elements 110
(FIG. 8I) and 120 (FIG. 8J) due to the increased amount of
compressive force that will be applied to a duct or tissue at this
location as compared to the compressive force that will be applied
to the duct or tissue adjacent the cutting zone 115 at sealing
zones 103.
[0100] The compressive force applied along the cutting zone 115
shown in FIGS. 8I and 8J may be altered by matching the curved or
arcuate active elements with an opposing active element that is
also curved, as shown in FIGS. 8K and 8L. For example, the arcuate
active element 120 shown in FIG. 8K may be paired with an arcuate
active element 110. The degree of curvature of the arcuate active
element 110 may be less than the degree of curvature of active
element 120, and the degree of curvature of either (or both) the
active element 120 and 110 can be adjusted to alter the compressive
force applied to a duct or tissue. As shown in FIG. 8K, the arcuate
active element 120 may curve in the same direction as arcuate
active element 110 in a quasi-complimentary orientation.
Alternatively, the compressive force along cutting zone 115 may be
substantially increased relative to the compressive force applied
along sealing zone 103 by having arcuate active elements curved in
opposite directions from each other, such as is shown in FIG.
8P.
[0101] Cutting zones 115 and sealing zones 103 may also be created
by altering the thermal conductivity along the surface of one of
the active elements, as shown in FIGS. 8M and 8N. For example,
active element 120 in FIG. 8M may be a support structure for
providing a compressive surface opposite active element 110. One or
more heat sinks 121 may be disposed adjacent the active element 110
(FIG. 8M) or 120 (FIG. 8N) to form a sealing zone 103 along a
portion of the active element 110 to draw away a greater amount of
heat from the active element on a portion thereof. As shown in
FIGS. 8M and 8N, a the spaced apart heat sinks 121 disposed
adjacent to the active element 120 and 110, respectively, may be
used to create a cutting zone 115 located generally in the center
of the active elements with sealing zones 103 on both sides of the
cutting zone 115, as the heat in the center portion is not drawn
away by the heat sinks.
[0102] FIG. 8O also shows an active element 110 having a cutting
zone and sealing zones 103. Rather than drawing heat away from
sealing zones 103 as discussed above relative to FIGS. 8M and 8N, a
heat spreader 123 of moderate thermal conductivity may be used to
concentrate a greater amount of heat along a cutting zone 115 as
compared to a sealing zone 103. As shown in FIG. 8O, the heat
spreader 123 may be disposed adjacent the active element 110 in a
central location so as to create a cutting zone 115 located
generally in the center of the active element 110 with a sealing
zones 103 on both sides of the cutting zone 115
[0103] Turning now to FIG. 9, there is shown a fragmented,
perspective view of the tips 20A, 20B of a sealing and cutting
instrument, such as sealing forceps, according to one aspect of the
invention. In contrast to FIG. 1, tip 20A in FIG. 9 may have an
active element 110 comprised of only a rigid loop 116 forming a
sealing and/or cutting element. The rigid loop 116 may be opposed
to surface 44 of tip 20B and aligned in a generally horizontal
orientation which would provide sealing and/or cutting at two
points when disposed perpendicular to a duct. It will be
appreciated, however, that the rigid loop 166 may be aligned in
different orientations to achieve a more specific therapeutic
effect, such as aligned vertically to achieve a single, more rapid
cut.
[0104] Rigid loop 116 may be formed of a conductor wire having a
ferromagnetic material disposed along at least a portion thereof,
typically circumferentially about a portion of the conductor wire.
The conductor wire may be of a sufficiently large gauge so that the
rigid loop 116 substantially resists deformation when tips 20A and
20B are used to apply pressure about a tissue or duct. For example,
to seal an artery it is important that sufficient pressure be
applied to the artery so that the endothelium of opposing walls of
the artery are adjacent each other. Then power may be supplied to
the active element 110 to seal the artery. It will be appreciated
that conductor wire is used herein for convenience only and those
skilled in the art will appreciate that other conductive material
may be used to form the rigid loop 116.
[0105] Sealing and cutting of a tissue or duct using tips 20A and
20B may occur sequentially. For example, the tips 20A, 20B may be
placed around tissue to be sealed and the tips forced together so
as to provide pressure on the tissue. Power may then be supplied to
active element 110 to heat the tissue or duct. Initially, sealing
of the tissue or duct will occur as the active element and/or the
tissue or duct may not exceed approximately 100.degree. C. as water
evaporates from the tissue or duct, i.e. the temperature of the
active element and/or the tissue or duct may be limited by the
phase change of water in the tissue or duct as it evaporates. Once
all water has evaporated, the temperature may then quickly rise to
cut the tissue or duct.
[0106] It will be appreciated that sealing and cutting of a tissue
or duct may be accomplished by supplying a constant power to the
active element 110. For example, a low wattage may be supplied to
the active element 110 to coapt lung tissue. The temperature of the
active element may be about 100.degree. C. until all water in the
lung tissue evaporates. This may take approximately 40 seconds when
the active element 110 is supplied with about 30 watts of
electrical energy. Once the lung tissue becomes desiccated the
temperature of the active element 110 may suddenly rise to commence
cutting of the tissue.
[0107] Turning now FIGS. 10A and 10B, there is shown an alternate
configuration of a tip 20A in perspective and from a
cross-sectional view, respectively. Tip 20A may have an active
element 110 disposed in a heat dispersing member 118. The heat
dispersing member 118 conducts heat away from the active element
110 so that heat may be applied to a tissue or duct more uniformly
along an outer surface of the heat dispersing element 118. Use of a
tip 20A having a heat dispersing member 118 may be more desirable
when a therapeutic procedure does not require cutting of the tissue
or duct. Because heat is less concentrated at a discrete location
along the tissue or duct, it may be treated using tip 20A without
being cut.
[0108] The heat dispersing member 118 may be a material that
resists sticking to a tissue when thermal energy is applied to the
tissue by active element 110, such as Teflon.RTM., Kapton.RTM.,
etc. It will be appreciated that tissue may stick to the active
element 110 until it reaches a sufficiently high temperature, e.g.
300.degree. C. However, active element 110 may not be used at such
high temperatures during some therapeutic procedures, such as
vascular shrinkage in aneurism preparation for clipping. Thus, use
of a non-stick heat dispersing member 118 during such procedures
may be necessary to avoid tissue sticking to the active element
110.
[0109] It will be appreciated that use of a non-stick material such
as Teflon.RTM., Kapton.RTM., etc., may be used on various surfaces
or elements in the embodiments described herein. For example, it
may be desirable to include a non-stick material on surface 44
opposed to active element 110 in FIG. 9 to ensure that heated
tissue does not stick to surface 44. A non-stick material may be
desirable in therapeutic procedures involving welding, sealing,
coapting, and/or homeostasis which involve temperatures at or below
approximately 100.degree. C.
[0110] Turning now to FIG. 11, there is shown another configuration
of tip 20A. Tip 20A may include active element comprised of a
ferromagnetic material in sheet form, such as Alloy 152. The sheet
of ferromagnetic material may be placed over a surface mounted
inductive coil (not shown) to form an active element 110 and
achieve a broad active surface that may be used to treat tissue.
Further, direct electrical connection may be provided to the sheet
of ferromagnetic material, instead of inductive coupling. This may
produce sufficient heat to deliver the desired therapeutic effect.
It will be appreciated that it may be desirable to use a thin sheet
of ferromagnetic material as the time to heat and cool the tip 20A
is dependent on the thermal mass of the material.
[0111] Referring now to FIGS. 12 and 13, there is shown still
another configuration of tip 20A. Tip 20A may be attached to an arm
30A and include an active element 110 having a sealing member 48
and a cutting member 112. Sealing member 110 may have a relatively
broad surface which may be used to seal, weld, or coapt tissue or a
duct or to achieve homeostasis. Sealing member 110 may, for
example, be a sheet of ferromagnetic material disposed on a
conductor similar to that described in FIG. 11, or a ferromagnetic
coating plated on a flattened conductor as described, for example,
in FIGS. 8A-8C.
[0112] The cutting member 112 may be a thin wire, such as a wire
coated with a ferromagnetic material which may allow a surgeon to
cut a tissue or duct at a more precise location. A surgeon may be
able to cut a tissue or duct using cutting member 112 and then use
the reverse side of the tip, the sealing member 48, to achieve
homeostasis. Alternatively, a surgeon may use the sealing member 48
to seal a tissue or duct and then flip the tip 20A over to make a
precise cut using the cutting member 112.
[0113] A surgical instrument may include more than one of the tips
shown in FIGS. 12 and 13 which are disposed opposite each other as
is more clearly shown in FIG. 14. Tissue or a duct may be grasped
between sealing members 48A and 48B. Sealing members 48A and 48B
may then be used to apply pressure to the tissue or duct. Power may
then be supplied to the sealing members to seal the tissue or duct.
Once the tissue is sealed, a surgeon may use either of the cutting
members 112A, 112B to cut and/or remove tissue if needed or
desired, or the sealed tissue may be left as is if there is no need
to remove tissue.
[0114] While some of FIGS. 1-13 show a single active surfaces or
elements on one side of the instrument, it will be appreciated that
an instrument may have complementary active surfaces 40 or elements
110 which either align with or are slightly offset from the other
active surface to ensure sealing and cutting of thicker ducts and
tissues, such as that which is in FIG. 14. This may be in the
context of forceps, scissor-like instruments or a host of other
surgical devices.
[0115] FIG. 15 shows a perspective view of a surgical instrument
200 having cooperating opposed active surfaces 40 with sealing and
cutting elements 110, 120 disposed on or extending from the active
surfaces in order to seal and cut a duct, tissue, etc., from
opposing sides. The surgical instrument 200 may be powered by a
cable 50 in a manner similar to that discussed with respect to FIG.
1.
[0116] The surgical instrument 200 can be used similar to forceps
to seal and cut veins and ducts, or can be used in a manner more
analogous to scissors. For example, in FIG. 1, active element(s) of
the surgical instrument 200 are being selectively activated to seal
and cut tissue, such as lung tissue, or other tissue in the body.
In such a manner diseased or damaged tissue can be cut out of the
body while also sealing the remaining tissue against the loss of
blood or other fluid and against the entry of bacteria, etc. The
surgical instrument 200 can be placed on an initial portion of
tissue and the sealing active element(s) (e.g. 120) activated to
seal the tissue and then the cutting active element(s) (e.g. 110 or
the sealing active element at different power) activated to cut
through the tissue. The surgical instrument 200 may be advanced and
the procedure repeated until the undesired tissue is completely cut
away.
[0117] Turning now to FIG. 16, there is shown a perspective view of
an alternate configuration of a surgical instrument 250 for use in
the present invention. Rather than operating like a pair of forceps
as shown in FIG. 15, the surgical instrument 250 functions in a
manner more analogous to scissors. Each active surface 40 is
attached to an arm 254 which extends to a pivot point 260 and then
to a handle portion 264 formed by finger holes 270 or some other
gripping structure.
[0118] The active surfaces 40 and/or active elements 110, 120 may
be formed as part of the arms 254, or may be attached to the arms,
such as by pivots 268, to allow the active surfaces or elements to
adjust relative to one another and apply pressure more uniformly on
a tissue than would occur in a scissors where there may be greater
pressure adjacent the pivot point 260. Thus, the sealing may be
more consistent as the active surfaces 40 and elements 110, 120
remain more parallel.
[0119] In use, the surgeon would position the active surfaces 40
along the area to be cut and apply force on the handle portion 264
while power is delivered through the cable(s) 50 from a power
supply to the active elements to thereby seal and cut tissue. If
necessary, the active surfaces 40 could then be advanced along the
tissue and the process repeated.
[0120] FIG. 17 shows a perspective view of a surgical instrument
200 having a rigid loop 116 cooperatively opposed to a surface 44.
The surgical instrument 200 may be powered by a cable 50 connected
to a power supply in a manner similar to that discussed with
respect to FIG. 1. One advantage of surgical instrument 200 having
a rigid loop 116 is that a user of the surgical instrument 200 may
be able to better view the tissue or duct that is to be sealed
and/or cut.
[0121] A sensor 119 may be disposed in communication with the
surgical instrument 200. As shown, the sensor 119 may be disposed
on the surface 44 and used to monitor electrical properties of the
tissue or duct. For example, when the surgical instrument 200 is
being used to seal and cut a tissue, evaporation of water may cause
the capacitance of the tissue to change and shift the standing wave
ratio ("SWR") of the applied electrical energy. The sensor may
detect the shift in the SWR and provide a signal of the transition
from sealing to cutting of the tissue by the surgical instrument.
Thus, the sensor 119 may provide the surgeon with an indication of
the effectiveness of the seal and the status of the sealing/cutting
taking place.
[0122] The sensor 119 may also monitor temperature of the interface
between the active element 110 and the tissue. Once a sufficient
temperature is achieved to cut the tissue, a signal may be
generated to notify the surgeon that the tissue has been cut or is
being cut. Thus, for example, the element 110 may hold at
100.degree. C. for a period of time. If pressure is being applied
to duct, etc., this will correspond with sealing. Once sealing it
complete, the water in the tissue will be consumed and the
temperature of the element 110 will suddenly rise, indicating
transition in to the cutting phase. To provide control, the
instrument 200, or some related structure, may advise the physician
which phase is currently being undertaken, or it may advise the
physician that sealing is complete and that cutting can
commence.
[0123] The surgical instrument 200 may include additional, or
alternate, sensors to monitor sealing and cutting of a tissue or
duct. For example, a thermocouple may be disposed integrally with
the surgical instrument to monitor temperature as the procedure
progresses from sealing to cutting and/or when cutting of the
tissue is complete. Alternatively, the electrical properties of the
conductor of active element 110 may indicate when sealing and/or
cutting of the tissue is complete. For example, if active element
110 is comprised of a tungsten conductor coated with a
ferromagnetic material, then the resistivity of the tungsten
conductor may be monitored to determine when sealing and/or cutting
is complete. As water evaporates from the tissue, the resistivity
of the tungsten conductor may increase. Thus, the resistivity of
the tungsten conductor may be correlated with the completion of
tissue sealing.
[0124] FIG. 18 shows a surgical sealing and/or cutting instrument
200 being used to treat tissue 208. The surgeon may position the
tissue 208 between the active elements 110, 120. The active
elements are then actuated to seal off a section of the tissue 212.
If so desired the section of tissue 212 can be cut using the
instrument 200 and removed from the surgical site, thereby leaving
the main tissue 208 sealed along the incision.
[0125] FIG. 19 shows an alternate configuration of a surgical
instrument 270 being used to cut a tumor 274 from lung tissue. As
was mentioned above, the active surface 40 and/or active elements
110/120 need not be linear and may be bendable. In FIG. 19, the
elements are disposed in a generally semi-circular configuration so
as to enable sealing around and cutting out of a tumor. (A
complementary portion to that shown may engage the tissue on the
opposing side and may lack any active elements so that it merely
engages the tissue, or may have one to two elements for promoting
sealing and cutting). In use the active elements 110, 120 are
positioned on the lung tissue just beyond the area to be removed.
The elements are then powered from a power supply via cable 50 to
seal off the lung tissue 280 (along thermally active element 120)
and to cut the portion of the lung tissue containing the tumor 274
(along thermally active element 110). Thus, the tumor is cut away
as the remaining lung tissue is sealed to thereby prevent air and
blood leakage, etc.
[0126] Turning now to FIGS. 20-28, various tools with parallel
linkages are shown which can be used, in accordance with one aspect
of the invention, in conjunction with tissue sealing/cutting
elements to selectively seal and cut or cut and seal ducts in a
human or animal. As tissue bundles or ducts to be sealed are
larger, parallel surface movement of the one or more treatment
surfaces may be desirable. If an angular movement instrument is
used with a larger tissue bundle, more pressure may be placed on
the proximate portion, i.e. the portion of the bundle or duct that
is closest to the pivot. This leaves the distal portion, i.e. away
from the pivot, with less pressure. With less pressure, it is
possible that the distal portion may receive little to no energy or
pressure from one or more of the treatment surfaces 40, or may not
be held in sufficient contact with adjacent tissue to form a good
seal. With parallel movement surfaces, the tissue bundle may
receive more-equal pressure on the proximate and distal portions.
Thus the heat may be approximately equally distributed along the
tissue bundle surface. This is particularly important when sealing
large ducts or tissues.
[0127] For small ducts or tissue bundles, such as small blood
vessels, forceps or jaws on a pivot (similar to scissors) may
adequately approximate parallel movement for the small movement
required. With larger ducts or tissue bundles, however, it may be
desirable to choose a parallel surface movement linkage as
discussed herein.
[0128] Turning now specifically to FIGS. 20 and 21, a side view of
a parallel movement surgical sealing and/or cutting instrument,
generally indicated at 10, is shown with the instrument in a nearly
closed position (FIG. 20) and in an open position (FIG. 21). The
instrument may include a parallel movement linkage, generally
indicated at 165. Such a parallel linkage has been referred to as a
pantograph linkage.
[0129] Two instrument halves 160A, 160B are connected by the
parallel movement linkage 165 so as to enable a treatment or active
surface 40A (or active elements 110 which may be embedded in or
extend from the treatment surface and a treatment or active surface
40B--which may have similar active elements) to move in parallel
with one another. The linkage has two arms or bars 180A, 180B that
are fixed at one end via fasteners 190A, 190B to the two instrument
halves 160A and 160B, respectively, and connected in the middle via
a fastener 190C. The opposing end of the bars 180A, 180B may
include fasteners 210A, 210B, respectively, or other connectors
which move in linear tracks 200A, 200B (FIG. 6) in the two
instrument halves 160A and 160B. When operated, the linkage causes
a line defined by fastener 190A and second bar end fastener 210B to
remain parallel to fastener 190B and second bar end fastener 210A
while the distance between these lines are adjusted. This X linkage
has been referred to as a pantograph linkage.
[0130] The instrument 10 may be operated with one hand. A user may
insert their fingers into the openings 220A, 220B. Using the
fingers, the user may separate the instrument halves 160A, 160B
causing the instrument tips 20A, 20B to separate as well.
Alternatively, the instrument halves 160A, 160B may be biased by a
spring in the open position. A tissue bundle may be placed between
the active surfaces 40A, 40B while the user may cause the
instrument tips 20A, 20B to apply pressure to the tissue bundle by
squeezing the instrument halves 160A, 160B together. One or both of
the active surfaces 40A, 40B may contain one or more active
elements 110 that may be activated at a first energy setting to
seal the tissue bundle. The user may then activate the one or more
active elements 110 (120, etc.) to cut the tissue bundle after
sealing. The instrument may then be removed from the tissue bundle.
The instrument 10 can move through tissue in a manner similar to
scissors, but enables a physician to seal and cut the tissue,
thereby avoiding the need to tie off blood vessel or sew up the
tissue because the tissue was sealed as well as being cut.
[0131] Turning now to FIGS. 22 through 24, side views of a parallel
movement sealing and/or cutting instrument 240 operable through a
small access port with a pistol grip are shown. The sealing and/or
cutting instrument 240 may be biased into either the open or closed
position depending on the use desired by the physician. In some
cases, it may be desirable that a parallel movement sealing and/or
cutting instrument fit within a trocar catheter or other cannula
such as a laparoscope, in order to gain access to the body. This
may be used, for example, when performing a laparoscopic tubal
ligation or other laparoscopic procedure. Therefore, a parallel
movement sealing instrument may include a configuration to fit
within an access port when closed, while facilitating movement of
the control mechanism outside the access port and actuation of the
sealing elements at the opposing end of the sealing and/or cutting
instrument. While the neck 290 shown in the figures may be short,
it should be recognized that the neck may be extended for
applications requiring longer access distance.
[0132] The parallel movement sealing instrument 240 (FIG. 22,
normally open bias; FIG. 23, normally closed bias) may include a
grip 260 trigger 272, bias mechanism 282, neck 290 and instrument
end 300. The bias mechanism 282 may aid the instrument to reset to
a known state, such as open or closed. The bias mechanism may be a
spring or elastic member that resists stretching and/or
compression. The neck 290 may be relatively short or long and may
include a movement transfer linkage to take force applied by the
trigger 270 and/or bias mechanism 282 and transfer the movement to
the instrument end 300.
[0133] The instrument end 300 may include the parallel movement
linkage 165 that enables a first treatment surface 40A to move in
parallel with a second treatment surface 40B, such as the linkage
described in FIGS. 20 and 21. One or both of the treatment surfaces
40A, 40B may include active elements 110, 120, etc. The treatment
surfaces 40A, 40B may reside on tips 230A, 230B.
[0134] A user may apply the instrument by one or more of the
following steps: selecting a surgical instrument having
substantially parallel surface movement; causing the surfaces to be
above and below a tissue to treat; reducing the distance between
the surfaces so that the surfaces (or the elements if the elements
extend from the surfaces) engage the tissue; and/or activating an
active element on at least one of the surfaces to thereby seal
and/or cut the tissue. In many applications, some force is applied
to the tissue by the treatment surfaces or active elements while
the tissue is being sealed and/or cut.
[0135] More specifically, a user may cause the instrument end 300
to become closed. The user may then insert the instrument 240 into
an access port in the body. The instrument end 300 may then be
opened and placed around a tissue bundle, duct, vessel, etc. The
user may then apply the trigger 270 such that the tips 230A, 230B
place pressure on the tissue being treated. One or both of the
treatment surfaces 40A, 40B may contain an active element 110 that
may be activated at a first energy setting to seal the tissue (via
an electric current from a power source as discussed above). The
user may then activate the one or more active elements 110 to cut
the tissue bundle after sealing. The instrument 240 may then be
removed from or advanced along the tissue bundle.
[0136] In FIG. 22, a normally open parallel movement sealing
instrument 240 is shown. The normally open parallel movement
sealing instrument may have the advantage of transferring the
pressure applied to the trigger 272 to the tips 230A, 230B, such
that the pressure on the tissue bundle may be regulated by the
user's squeeze on the trigger 272.
[0137] In FIG. 23, a normally closed parallel movement sealing
instrument 240 is shown. The normally closed parallel movement
sealing instrument may have the advantage of consistent applied
pressure by the bias mechanism 282 and the fact that a user would
not be required to maintain pressure on the trigger 270 when closed
on the tissue being treated.
[0138] Turning now to FIG. 24, a mechanical diagram of FIG. 22 is
shown. An activation button 310 and trigger linkage 320 may be seen
more clearly. The activation button may be used to apply power to
the thermally active element 110. The trigger linkage 320 may
include a post in a track allowing trigger 272 movements to be
translated into linear movement of a rod 330. The rod 330 may be
connected to the parallel movement linkage 165, allowing the
transfer of force from the trigger 272 to parallel movement linkage
165.
[0139] Turning now to FIG. 25, a parallel movement end 380 for the
sealing instrument is shown. The parallel movement end 380 may be
configured in a module 390. In one embodiment, the module 390 may
be added to instruments that use forward and backward linear
movement of a rod. For example, a sleeve could be attached to the
module 390 and the rod attached to one of the bars 180a or 180b. As
the rod moves forwardly and rearwardly, the tips 230A, 230B move
toward and away from one another.
[0140] Turning now to FIGS. 26 and 27, parallel movement sealing
instruments 400, 450 are shown with alternate movement transfer
linkages. FIG. 26 shows a movement transfer linkage with finger
rings. Separation of a moving ring 410 from the stationary rings
420 may cause motion to be applied to the parallel linkage 430.
Depending on how the moving ring and stationary ring are attached
to the bars 180A, 180B forming the parallel linkage, moving the
moving ring 410 toward the stationary ring 420 will either open or
close the space between the tips 230A, 230B.
[0141] FIG. 27 shows a sealing instrument 450 with a movement
transfer linkage 430 connected to a handle 440 with a squeeze grip
trigger. Application of pressure to a front end 470 of the grip may
cause the movement of the squeeze trigger to be transferred to the
parallel linkage 430.
[0142] FIG. 28 shows a side view of an alternate embodiment of a
surgical instrument 335 made in accordance with principles of the
present invention. The instrument 335 is configured with a parallel
movement linkage to keep the active surfaces parallel to one
another. The parallel linkage may include a direct linkage 340. As
the trigger 290 is squeezed, the linkage 340 may rotate, advance or
otherwise cause a movable tip 370 to approach a stationary tip 360.
As the trigger is released, the movable tip 370 may withdraw from
the stationary tip 360.
[0143] The instrument 335 may include one or more active surfaces
40 on tips 360, 370. The active surfaces 40 may apply pressure to
seal and cut tissue, including ducts such as blood vessels,
fallopian tubes, etc., as described above.
[0144] While not shown in all of FIGS. 22 through 28, will be
appreciated that thermally active elements would be disposed on
opposing sides of the tips and would be disposed in communication
with a power source to selectively heat the active elements.
[0145] Turning now to FIG. 29, a chart correlating estimated tissue
effects with temperature is shown. It should be recognized that
these temperature ranges are estimates, and that temperatures may
vary depending on multiple factors that may include tissue type,
tissue make-up, and water content. Vascular welding is estimated to
occur near the range of 58.degree. C. to 62.degree. C. Hemostasis
is estimated to occur near the range of 70.degree. C. and
80.degree. C. Searing and sealing is estimated to occur near the
range of 80.degree. C. and 200.degree. C. Incision is estimated to
occur near the range of 200.degree. C. and 400.degree. C. Rapid
ablation and vaporization is estimated to occur near the range of
400.degree. C. and 500.degree. C.
[0146] It will be appreciated that the surgical instrument of the
present invention has a wide variety of uses. As the tips are
applied to a piece of tissue, the surgical instrument is aligned
with respect to the tissue so as to extend across the area to be
sealed and/or cut. The active surfaces will typically firmly engage
the tissue and then the physician will activate the thermally
active elements to cut and/or seal the tissue. It will be
appreciated that the cutting could be done first, or the sealing
can be done first, depending on the particular desires of the
physician. Alternatively, a surgical instrument could be made in
accordance with the present invention that operates with programmed
order, such as sealing for a given amount of time and then cutting
the tissue without the physician having to activate each step.
[0147] It will also be appreciated that respective elements can be
heated to seal and/or cut the tissue. While it is preferred that
the active surfaces be parallel and very close to one another, it
will be appreciated that such is not necessary in accordance with
the principles of the present invention.
[0148] There is thus disclosed an improved tissue cutting and
sealing instrument. It will be appreciated that numerous changes
may be made to the present invention without departing from the
scope of the claims.
* * * * *