U.S. patent number 3,636,943 [Application Number 04/678,649] was granted by the patent office on 1972-01-25 for ultrasonic cauterization.
This patent grant is currently assigned to Ultrasonic Systems, Inc.. Invention is credited to Lewis Balamuth.
United States Patent |
3,636,943 |
Balamuth |
January 25, 1972 |
ULTRASONIC CAUTERIZATION
Abstract
The method and apparatus of the invention use ultrasonic energy
in the form of mechanical vibrations transmitted by a tool member
to close off small severed blood vessels, such as in humans, by the
formation of closures at the terminal portions thereof, and stop
what is called "ooze," that requires constant mopping or cleansing
techniques during an operation. This tool member may be in the form
of a knife ultrasonically vibrated to simultaneously sever and
close off respective terminal portions of the severed blood vessels
while performing surgical procedures. The tool member, of a proper
configuration, may also join together layers of tissue, including
the walls of unsevered blood vessels, and with respect to the
latter is foreseen as replacing the "tying off" of arteries and
veins currently necessary in surgery.
Inventors: |
Balamuth; Lewis (New York,
NY) |
Assignee: |
Ultrasonic Systems, Inc.
(Farmingdale, NY)
|
Family
ID: |
24723702 |
Appl.
No.: |
04/678,649 |
Filed: |
October 27, 1967 |
Current U.S.
Class: |
601/2; 156/73.3;
606/169 |
Current CPC
Class: |
A61B
17/11 (20130101); A61B 17/12 (20130101); A61B
18/00 (20130101); B29C 66/861 (20130101); B29C
66/9516 (20130101); B29C 66/9512 (20130101); B29C
66/8227 (20130101); B29C 66/8322 (20130101); B29C
65/7443 (20130101); B29C 65/08 (20130101); B29C
66/81417 (20130101); A61B 18/20 (20130101); A61B
2017/320093 (20170801); A61B 2017/320069 (20170801); A61B
2017/320094 (20170801); A61B 2017/00504 (20130101); B29C
66/9513 (20130101); B29L 2023/005 (20130101); B29C
66/9517 (20130101); A61B 2017/320095 (20170801) |
Current International
Class: |
A61B
17/28 (20060101); A61B 17/12 (20060101); A61B
18/00 (20060101); B29C 65/08 (20060101); B29C
65/74 (20060101); A61B 17/32 (20060101); A61b
017/36 (); A61b 017/32 (); A61h 023/00 () |
Field of
Search: |
;128/2.1,24.05,303.13-303.19,305,24A ;156/73 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Pinkham; Richard C.
Assistant Examiner: Apley; Richard J.
Claims
I claim:
1. A method of superfically cauterizing a wound at the terminal
portion of severed blood vessels in vivo, with a noncutting
spatulalike tool member having a working surface, comprising the
steps of
A. applying the working surface of said tool member in engagement
with the terminal portion of said blood vessels, said tool member
being at substantially room temperature,
B. retaining said tool member in a position relative to said
severed blood vessel,
C. maintaining a compressive force against said terminal portion in
a plane substantially normal to said engaged surface with said
noncutting spatula like tool member,
D. vibrating the working surface of said tool member at a peak
velocity of at least 10 feet per second and simultaneously with the
maintaining of said compressive force to apply ultrasonic
mechanical rubbing vibrations substantially parallel to the
terminal portion of said blood vessels in a direction so as to
apply an additional energy producing force to obtain a localized
heating of the terminal portion, the direction of said mechanical
vibrations being applied to produce shear waves at the terminal
portion of said blood vessels, and said blood vessels, and said
localized heating of the blood vessels is obtained by the
conversion of said shear waves into heat, whereby said superfical
cauterization is produced at least in part by the production of
said shear waves, and
E. continuing the retaining of said tool member in a position
relative to said severed blood vessels and the application of said
mechanical rubbing vibrations for a period of time sufficient for
said localized heating to form a superfical cauterization at the
terminal portion, whereby the terminal portion is closed off and
the blood contained therein is prevented from escaping.
2. A method as claimed in claim 1, wherein said localized heating
is also obtained by simultaneously inducing frictional rubbing at
said terminal portion of said blood vessel by the application of
said mechanical vibrations, whereby said cauterization is produced
at least in part by said frictional heating.
3. A method as claimed in claim 1, wherein said blood vessel is
relatively small in diameter and said cauterization is
substantially formed by clotting of the blood at said terminal
portion thereof.
4. A method as claimed in claim 1, wherein said cauterization is at
least in part formed by a blood clot, and said localized heating
expedites the formation of said blood clot.
5. A method as claimed in claim 1, wherein said cauterization is
formed by partially closing the blood vessel by said localized
heating and the remainder by clotting the blood contained in said
reduced area of the blood vessel.
6. A method as claimed in claim 1, wherein said mechanical
vibration produces a plastic flow of the wall of said blood vessel
and said flow is continued for a period of time sufficient to
obtain a joining of the wall of said blood vessel to form said
closure.
7. A method as claimed in claim 1, wherein said blood vessel is a
capillary.
8. A method as claimed in claim 1, wherein said blood vessel is an
arterial.
9. A method as claimed in claim 1, wherein said blood vessel is a
veinule.
10. A method as claimed in claim 1, wherein said blood vessel is an
artery.
11. A method as claimed in claim 1, wherein said blood vessel is a
vein.
12. A method as claimed in claim 1, wherein said ultrasonic
mechanical vibrations are applied over and area to simultaneously
close off a plurality of blood vessels.
13. A method of superfically cauterizing severed blood vessels of a
wound in vivo, with the aid of a noncutting spatula like tool
member having a working surface, comprising the steps of
A. applying the working surface of said tool member against the
terminal portion of said blood vessels, said tool member being at
substantially room temperature,
B. retaining said tool member in a position relative to said
severed blood vessels,
C. maintaining a compressive force applied along a line
substantially perpendicular to the plane defined by the terminal
portion of said blood vessels with said noncutting spatula like
tool member,
D. simultaneously vibrating the working surface of said tool
member, at a peak velocity of at least 10 feet per second and,
while maintaining said compressive force, in a direction and at an
ultrasonic rate to transmit mechanical vibrations to the terminal
portion, said localized heating is obtained by inducing friction
rubbing at the terminal portion of said blood vessels by the
application of said mechanical vibrations, and
E. continuing the retaining of said tool member in a position
relative to said severed blood vessels and the application of said
compressive force and mechanical vibrations until a superfical
cauterization at said terminal portion is formed, whereby the blood
contained therein is prevented from escaping.
14. A method as claimed in claim 13, further including the step of
controlling the rate of frictional heating of the terminal portion
of said blood vessel.
15. A method as claimed in claim 14, wherein said rate of
frictional heating is controlled by texturing said toolworking
surface to a surface roughness selected in accordance with the
ultrasonic rate of vibration and compressive force to be
applied.
16. A method as claimed in claim 13, wherein the application of
said mechanical vibrations also simultaneously produce at least in
part shear waves at said terminal portion, and the frequency and
amplitude of vibration of said tool member is selected at a level
wherein said transmitted shear waves are substantially maintained
at the terminal portion with only superficial penetration and
heating of the remainder of said blood vessel.
17. A method as claimed in claim 13, wherein said peak velocity is
in the range of approximately 40 feet per second to 100 feet per
second.
18. A method as claimed in claim 13, wherein said working surface
is vibrated in an elliptical pattern.
19. A method as claimed in claim 13, wherein said mechanical
vibrations are produced by vibrating the tool member to obtain
longitudinal vibrations along said working surface, which working
surface is maintained along a plane substantially parallel to the
plane defined by the terminal portion of said blood vessel.
20. A method as claimed in claim 13, wherein said tool working
surface is of sufficient area to simultaneously cauterize
respective terminal portions.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates generally to improvements in surgical
procedures whereby ultrasonic energy is utilized and more
particularly to methods and apparatus for closing off the terminal
portions of severed blood vessels to stop or prevent the flow of
blood therefrom during the surgical procedure and the joining of
layers of tissue in biological organisms such as humans.
The outstanding and unexpected results obtained by the practice of
the method and apparatus of the present invention, are attained by
a series of features, steps and elements, working together in
interrelated combination, and may be applied to biological
organisms in general and particularly humans, and hence will be so
illustrated and described with respect to humans.
Applicant has already participated in earlier developments which
led to U.S. Pat. No. 3,086,288 covering the use of an
ultrasonically vibrating scalpel or knife. The aim of that
invention was to increase the ease with which a surgical knife
could be used to cut organic tissues.
We are concerned in the present invention with new discoveries by
applicant which allow dramatic improvements in the operation of
high-frequency vibrated knives, and also extend the use of the side
area or working surface of a knife to perform a useful function,
especially in relation to preventing or stopping bleeding.
Before proceeding to the details of the invention, let us first
review briefly generally known facts of bleeding. The blood or
circulatory system of the body (for warm blooded animals and
humans) is comprised of two great and complex systems of arteries
and veins. The arteries carry blood from the heart and these
arteries divide in a complex network of smaller arteries or
arterials, which in their turn connect to an extraordinarily
complex network of very fine blood carrying tubes called
capillaries. These capillaries are in communication with all the
cells of the body and they provide the nutrients needed to feed
these cells and they also supply the white blood cells needed to
dispose of wastes and, in general, to police the cells and their
environment in respect to unwanted substances and agents. After
doing their job, the blood cells find their way back to the heart
by means of a similar network of capillaries which join up to
veinules or small veins, which in turn connect to veins which
ultimately bring the blood back to the heart. There is also a lymph
system which participates in this process, wherein again small
tubes containing lymph (a kind of blood plasma with white
corpuscles and waste products) convey this lymph through various
strainers called lymph nodes and then, ultimately by means of the
thoracic duct the purified lymph flow back into a large vein in the
neck.
Now when the body is cut into at any location, in general a number
of the tubes or vessels carrying blood are severed in this region.
This severance will include many capillaries, some small veins and
arteries and in some cases even a regular artery or a vein or both.
The capillaries comprise an area which is as much as 100,000 times
the area of the arteries and veins, and thus it is seen that many
more capillaries are involved per incision than any other vessels.
The severing of capillaries produces an ooze of blood which must be
mopped up or swabbed during an operation, while the larger blood
vessels involved must be clamped or tied off to prevent bleeding
during the surgery. The attending of these bleeding problems takes
up about 67 percent of the time of most operations. It is a major
aim of this invention to reduce this lost time considerably and at
the same time to reduce the total loss of blood and to promote the
healing of the wounds created. This is accomplished by the design
of ultrasonic instruments so as to enhance those uses of ultrasonic
energy needed to accelerate the desired objective, namely to stop
bleeding.
Ordinarily, bleeding stops by virtue of the interaction between
small bodies in the blood stream called platelets and the oxygen in
the air, whereby the platelets disintegrate and form a network of
fibers called fibrin which slow up and finally stop the blood flow
by the formation of suitable clots. Heat may be used to accelerate
this process, and in fact both electric cautery and hot wire
cautery are used in controlling bleeding in some procedures. But
these types of cautery produce, in addition to rapid clotting, an
extensive destruction to all tissue, thereby requiring a long time
in the healing. By means of ultrasonic energy it is possible to
promote the clotting with far less damage, as will be disclosed
herein, so that bleeding may be very quickly halted and at the same
time, much quicker healing will take place.
Electric and hot-wire cautery as well as cryogenic techniques are
not effective for the care of bleeding from veins and arteries and
it is here that special tying-off methods or hemistatic clamping
techniques are used. It is a further aim of this invention to teach
how tying-off and clamping techniques may be replaced by utilizing
ultrasonic energy in the proper way.
In all the ways whereby ultrasonic energy is used in this
invention, the tool member supplying the energy executes vibrations
of high frequency and small amplitude. Since the development of the
ultrasonic knife, in part by present applicant, new alloys have
become generally available which permit the maximum amplitude of
vibration at a given frequency to be increased substantially. For
example, in regular use a scalpel could be vibrated at 20 kc./sec.
with a stroke of two to at most four thousandths of an inch. A
larger stroke would cause a rapid fatigue failure of the ultrasonic
motor driving the scalpel. With a new alloy of titanium (titanium
with 6 Al- 4 V is one such) it is possible to go to strokes as high
as 8 or 10 thousandths of an inch. This means that the rubbing
action of a single stroke may be greatly enhanced, because the peak
velocity achieved during the stroke is more than double the peak
velocities previously attainable on a practical basis.
This improvement led applicant into the development of procedures
and tools whereby such large ultrasonic motions could be put to
work to stop capillary bleeding while cutting the surrounding
tissue. In order to understand this, let us consider the transfer
of energy which occurs during cutting. Wherever the tissue comes
into contact with the cutting tool or scalpel, the tool member is
moving to and fro at high frequency parallel to the surface of the
tissue being severed. To the extent that there is good acoustic
coupling between tissue and tool, there will be a transfer of shear
waves into the tissue. But, tissue is of an acoustic nature as to
be practically incapable of supporting high-frequency shear waves.
Therefore, the shear waves damp out very rapidly and dissipate
their energy in the superficial tissue as heat. This promotes
fibrin formation and clotting at the capillaries, while the damage
to underlying tissue is minimal due to lack of penetration of this
clotting energy. To the extent that the tool slips past the tissue
during its to and fro motion, a rubbing action is set up, due to
relative motion of tool and tissue and a frictional heat is
generated at the tool tissue interface, again producing a heating
and clotting action on the adjacent terminal portion of the opened
capillaries and other blood vessels. Thus, entirely due to the
ultrasonic to and fro motion of the tool, a cooperative dual effect
is engendered whereby the "ooze" during an operation is effectively
stopped while cutting.
Applicant has further found that the peak rubbing speed, which
equals .pi.fx the peak to-and-fro stroke (f = frequency of tool) is
relatively constant with respect to frequency. This is because the
peak strain set up in the ultrasonic motor driving the cutting tool
depends directly on the peak speed of the cutting tool and not on
the peak frequency. Of course, this merely means that if one wishes
to operate at a higher frequency, then one has to be content with a
proportionately diminished to and fro stroke of the tool. In any
case, due to the cooperative effect, above outlined, essentially
all of the energy of the tool is used in local, superficial
heating, except for that used to actually sever the tissue itself.
This latter component of energy is only a small fraction of the
total energy used.
In actual practice, applicant has discovered that, by texturing or
roughening the sidewalls of the cutting tool, the transfer of
superficial cauterizing energy is increased so as such for certain
surgical procedures it is preferable to use scalpels whose working
surfaces or side faces are roughened rather than very smooth. The
same principle applies to spatulate tools wherein no cutting is
contemplated, but the tool is designed primarily to cauterize an
already opened bed of blood vessels such as capillaries in a wound.
In the case of the spatulate tool the amount of energy transfer may
be increased by pressing the spatula tool working surface, while
vibrating, with increased pressure against the wound to apply a
compressive force for the transmission of the shear waves or
increasing the frictional rubbing. Applicant has also discovered,
that although it is not essential, it is nevertheless desirable to
supply the cutting edge of a knife or scalpel with a set of small
serrations. This further aids in clotting, and permits faster
cutting, while at the same time halting capillary bleeding.
Now, in addition to all of the above there are still additional
aids arising from the use of ultrasonic energy during the cutting
operation. This arises because the collagenous substances in the
walls of the capillaries and also in those of veins and arteries,
are capable of being joined or sealed together by the application
of said high-frequency energy. In fact, it is just this property
which makes it possible to close off a vein or an artery by
clamping it in a specially designed ultrasonic instrument, so that
the walls of said blood vessel are briefly clamped while vibrating
one or both of the tool jaws. Since this same principle applies to
other soft body tissue such as the skin, this same type of tool may
be used in place of the conventional suturing which is used in
closing incisions in surgical procedures.
Thus, it may be seen that we are dealing with a highly complicated
set of phenomena in practicing applicant's method of bloodless
surgery. At this time, it is not known quantitatively just how
large a role is played by each factor, such as shear wave
absorption, frictional heat production and tissue sealing. The
point is that by employing ultrasonic motors capable of producing
generally higher strokes than previously available, the combination
of effects permits for the first time, true bloodless surgical
procedure by ultrasonic means. Where extremely fast procedures are
essential, one may also resort to auxiliary heating of the
vibrating tool member, but only to subcautery temperatures. This
temperature is preferably above room temperature but below a
temperature that would normally burn the tissue. This may be
accomplished conventionally, or in accordance with the method
disclosed in U.S. Pat. No. 3,321,558 in which applicant is a
coinventor.
OBJECTIVES OF THE INVENTION
An object of the present invention is to provide an improved method
and apparatus for forming surgical procedures with ultrasonic
energy.
Another object of the present invention is to provide an improved
method and apparatus for securing together layers of tissue in
biological organisms, such as humans.
Yet another object of the present invention is to provide an
improved method and apparatus for forming closures at the severed
terminal portions of blood vessels in vivo, which blood vessels are
in the general neighborhood of what are called capillaries, so as
to prevent "ooze," which requires contact mopping or cleansing
during surgical operations.
A further object of the present invention is to provide improved
method and apparatus for permanently or temporarily closing off
blood vessels so as to replace the "tying off" of arteries and
veins currently necessary in surgery.
Still another object of the present invention is to provide a
method and apparatus of bloodless surgery which combines the
surgical cutting of tissue and a closing off of the severed blood
vessels to prevent the "ooze" normally associated with
operations.
Yet still another object of the present invention is to provide a
method and apparatus for simultaneously joining and trimming, as by
cutting, a large blood vessel.
Yet still a further object of the present invention is to provide
an improved method and apparatus for ultrasonically joining
together layers of tissue.
Still a further object of the present invention is to provide an
improved method and apparatus for increasing the flow of oxygen to
the terminal portion of the severed blood vessel to expedite the
clotting of the blood thereat.
Still yet a further object of the present invention is to provide
an improved sealing apparatus for joining together layers of human
tissue.
Still yet a further object of the present invention is to provide
specially designed tools adapted to be ultrasonically vibrated and
employed in surgical procedures.
Other objects and advantages of this invention will become apparent
as the disclosure proceeds.
BRIEF DESCRIPTION OF THE DRAWINGS
Although the characteristic features of this invention will be
particularly pointed out in the claims, the invention itself, and
the manner in which it may be made and used, may be better
understood by referring to the following description taken in
connection with the accompanying drawings forming a part hereof,
wherein like reference numerals refer to like parts throughout the
several views and in which:
FIG. 1 is a chart indicating the relationship of the principal
factors affecting the practicing of the present invention for
surgical procedures;
FIG. 2 is an assembled somewhat schematic view of an ultrasonic
motor generator system of the type in which the motor is capable of
being hand held and manipulated, for driving a tool member adapted
to engage the biological organism for performing a surgical
procedure, and which in the present instance the tool member is
illustrated as a knife for severing blood vessels, the latter shown
on a greatly enlarged scale for discussion purposes;
FIG. 3 is a side view of an ultrasonic tool member having a
textured working surface in accordance with the present
invention;
FIGS. 3A and 3B are end views of the tool member in FIG. 3 and
illustrates two preferred ways of obtaining the textured working
surface;
FIG. 4 is a greatly enlarged schematic representation of a portion
of a tool member with its working surface in engagement with the
terminal portion of a blood vessel for forming a closure thereat to
prevent the flow of blood from said terminal portion;
FIG. 4A is an enlarged section view taken along line 4A--4A of FIG.
4 to illustrate the interfacial contact between the tool working
surface and blood vessel for the transmission of frictional energy
and shear waves for localized heating of the terminal portion;
FIG. 4B is a greatly enlarged schematic representation illustrating
an ultrasonically vibrating tool member engaging a severed portion
of tissue for simultaneously forming a plurality of closures at the
terminal portions thereof;
FIG. 4C is a greatly enlarged schematic representation illustrating
the angular relationship between the tool member and blood vessel
which defines a terminal plane that may define an extreme angle
with the axis of the blood vessel and still obtain the desired
results of the present invention;
FIG. 4D is an end view of the tool member and blood vessel of FIG.
4C;
FIGS. 5, 5A, 5B and 5C are enlarged schematic representations in
cross section of the method of forming a closure at the terminal
portion of a blood vessel in which the sidewalls thereof are joined
together;
FIG. 5D is an extremely enlarged view of a blood specimen to
illustrate some of the important components thereof;
FIGS. 6 and 6A are enlarged schematic representations in cross
section of the method of forming a closure at the terminal portion
of a blood vessel in which the closure is formed by partially
converging the sidewalls thereof and forming a blood clot in the
reduced opening;
FIGS. 7 and 7A are enlarged schematic representations in cross
section of the method of forming a closure at the terminal portion
of a blood vessel in which the closure is formed by primarily
forming a blood clot at the terminal portion thereof;
FIGS. 8 and 8A are side and end elevational views respectively, of
a spatula tool member having a textured working surface for
ultrasonic cautery;
FIG. 9 is an enlarged sectional view illustrating the forming of a
plurality of closures on respective terminal portions in an open
wound by the use of a spatula-shaped tool;
FIG. 10 is a top longitudinal view, of one preferred form of
ultrasonic system, of the type capable of being hand held and
manipulated, for joining together layers of tissue, such as in
humans;
FIG. 11 is a side longitudinal view, partly in cross section, of
the ultrasonic system of FIG. 10;
FIG. 12 is an enlarged schematic view, in cross section,
illustrating the application of the ultrasonic instrument
illustrated in FIGS. 10 and 11 for securing together the walls of a
blood vessel;
FIG. 12A is an enlarged schematic view, in cross section, similar
to FIG. 12 illustrating the actual joining of the overlapping wall
portion;
FIG. 12B is a further enlarged schematic view, in cross section,
showing the actual bond obtained between the wall portions of the
blood vessel;
FIG 12C illustrates the ultrasonic system as used for
simultaneously joining and cutting layers of tissue; and
FIG. 12D illustrates the ultrasonic system clamping means for
intermittently joining overlapped layers of tissue.
DETAILED DISCUSSION OF THE DRAWINGS
The high-frequency transducer means may be either in the sonic or
ultrasonic frequency range but for purposes of the present
invention the word "ultrasonic" will be used to denote vibrations
in the range of approximately 5,000 to 1 million cycles per second.
In addition the term "blood vessel" as used herein is intended to
include any tubular member of the human body, but particularly
capillaries, arterials, veinules, arteries and veins.
In performing the surgical procedures of the present invention
there are several factors that have to be taken into consideration
and analyzed in terms of a total or effective value to obtain the
desired end results. The term "total value" may be defined as the
proper combination of these factors to obtain the desired end
result.
Referring now to the drawings, FIG. 1 is a chart illustrating the
relationship of the seven principal factors which are involved in
whole or in part for determining the total value associated with
forming closures at the terminal portions of severed blood vessels,
or joining together overlapping segments of layers of human tissue.
The related factors are-- peak tool velocity, frequency of
vibration, pressure applied with tool, tool working surface,
cutting edge, tool temperature and oxygen for clotting. These
factors vary with respect to the procedure being performed.
In the embodiments of the invention discussed below the working
surface of the tool member is placed in engagement with at least
one of the layers of tissue at a surface thereof such that a small
compressive force is applied in a plane substantially normal to the
engaged surface. While this compressive force is maintained the
working surface of the tool member is vibrated at an ultrasonic
rate to apply an additional energy producing force at the engaged
surface. The compressive and energy producing forces are continued
until the layers of tissue are secured together by the combined
action of these forces.
When these layers of tissue form the walls of blood vessel the
forces are applied to the terminal surface thereof for producing
localized heating in forming a closure to prevent the blood from
escaping therefrom. The energy producing force may be divided
into-- mechanical vibration energy absorption in tissue-- and--
frictional rubbing heat development in tissue-- both of which
result in a localized heating of the walls of the blood vessel to
obtain the-- tissue closure. The performing of surgical procedures
as related to this aspect of the invention is discussed with
reference to FIGS. 2 through 9, inclusive.
In contrast to this we have the joining of layers of tissue in
overlapping relation to each other and in which case the
compressive and vibrational forces are applied to one of the
overlapped surfaces in a plane substantially normal thereto and in
which case we primarily rely on-- mechanical vibration energy
absorption in tissue-- to obtain the -- tissue joining. The
performing of surgical procedures as related to this aspect of the
invention is discussed with reference to FIGS. 10 through 12D,
inclusive.
Referring again to the drawings, and with respect to FIG. 2, it
will be seen that an apparatus 10 for ultrasonically performing
surgical procedures on a biological organism, such as a human, may
include an ultrasonic transducer or motor 11 for effecting the
necessary high-frequency vibrations of the tool member 13, such as
a knife, having a sharp output edge or surface 15 with a working
surface 16. The ultrasonic motor 11, as illustrated may be in the
form of a driving member adapted for being hand held as by an
operator 12, and generally comprising a tubular housing or casing
14 into which an insert unit 17 supporting the tool member 13 may
be partially telescoped. The ultrasonic motor 11 is energized by an
oscillation generator 18, with a power cable 19, connecting the two
together. The generator is an oscillator adapted to produce
electrical energy having an ultrasonic frequency.
The ultrasonic motor 11 may be one of a variety of
electromechanical types, such as electrodynamic, piesoelectric and
magnetostrictive. The ultrasonic motor for effecting surgical
procedures through hand directed tools of suitable configuration,
which are readily replaceable or inter-changeable with other work
performing tools in acoustically vibrated material treating
devices, may be of the type disclosed in U.S. Pat. No. Re. 25,033,
3,075,288, 3,076,904 and 3,213,537, and wherein each work tool
member is rigidly joined, in end-to-end relationship to a
connecting body or acoustic impedance transformer and to a
transducer which may form an insert unit or assembly which is
removably supported in a housing containing a coil in surrounding
relationship to the transducer and receiving alternating current
for producing an alternating electromagnetic field.
The transducer in the ultrasonic motor 11 is longitudinally
dimensioned so as to have lengths which are whole multiples of
half-wavelengths of the compressional waves established therein at
the frequency of the biassed alternating current supplied so that
longitudinal loops of motion as indicated by arrow 23, occur both
at the end of the insert unit 17 to which the tool member 13 is
rigidly connected and the knife edge. Thus, the optimum amplitude
of longitudinal vibration and hyperaccelerations of tool member 13
is achieved, and such amplitude is determined by the relationship
of the masses of the tool member 13 and insert unit 17 which may be
made effective to either magnify or reduce the amplitude of the
vibrations received from the transducer.
The tool member 13 may be in the form of relatively flat metal
spatula member, as shown in FIGS. 8 and 8A, hereinafter discussed
in detail, to provide relatively wide surface areas for contact
with the tissue to which the vibrations are to be applied for
effecting the closure of severed blood vessels.
The tool member 13 may be permanently attached to the end of insert
unit 17, for example, by brazing, solder or the like, or the tool
may be provided with a threaded stud 20 adapted to be screwed into
a tapped hole in the end of insert unit 17 for effecting the rigid
connection of the tool to the stem. A base portion 21 is provided
from which the stud 20 extends, from one end thereof, and from the
other end a body 28 which is firmly secured thereto for the
transmission of the ultrasonic vibrations. The body 28 may be
brazed or welded to the base 21 of the tool member 13. A tapered
surface 22 may be provided which connects the cutting edge 15 with
the working surface 16.
As seen somewhat schematically in FIG. 2 the biological organism
25, such as a human, contains a layer of outer tissue or skin 26,
an internal cellular structure 27 with a plurality of blood vessels
30 extending therethrough shown in an enlarged scale, as well as in
the skin (not shown).
FIGS. 3, 3A and 3B illustrate various types of replaceable surgical
implements, such as knives, that may be employed in accordance with
the present invention. The knife 13a of FIG. 3 is similar to that
illustrated in FIG. 2 and includes a base portion 21a, capable of
supporting ultrasonic vibrations and adapted to be set into
vibration in a given direction by the driving member. A threaded
stud 20a extends from one end of the base 21a for engagement with
the insert unit. The body portion 28a, in the form of a cutting
blade, extends from the opposite end of the base 21a and includes a
textured working surface 16a for enhancing the coupling action
between the tool member 13a and the terminal portion of the severed
blood vessels to be engaged. The cutting edge 15a may be serrated
and have an outwardly tapered portion 22a between the cutting edge
15a and the substantially flat working surface 16a. The textured
surface 16a may begin in close proximity to or start at the working
edge 15a so that when cutting and sealing small capillaries the
rubbing action and transmission of shear waves begins immediately.
The textured surface finish of 16a may vary from a micro finish in
the range of 10 microinch to 10,000 microinch, but preferably in
the range of 40 microinch to 200 microinch.
As illustrated in FIG. 3A the tool member 13a includes a body
portion 28a having a coated textured layer of friction inducing
material 29a which forms the working surface 16a and which may be
of diamond or steel powder particles bonded to the body portion in
any conventional manner well known in the art, to obtain the
desired micro finish. The layer of coated material may be applied
to both surfaces of the tool member and each surface may be of the
same or different microfinish to obtain a debriding and superficial
cauterizing. The advantages are quicker healing as well as less
damage to the tissue being treated.
FIG. 3B illustrates the obtainment of the working surface 16a by
finishing the metallic body 28a in any conventional manner to
obtain the desired surface roughness. By providing the textured
surface it is possible to control the rate of frictional heating of
the blood vessels. The surface roughness is generally selected in
accordance with the ultrasonic rate of vibration and the
compressive force to be applied. This will in many instances relate
to the particular surgeon performing the operation.
THEORY OF PRESENT INVENTION
Whereas a scientific explanation of the theory based on the
phenomena involved is disclosed below, it is to be clearly
understood that the invention is by no means limited by any such
scientific explanation.
Applicant has now discovered that mechanical vibrations properly
applied may produce closures at the terminal ends of blood vessels
to prevent the flow of blood therefrom and also join together
layers of human tissue. With respect to forming the terminal
closure it is possible to simultaneously cut through layers of
tissue and seal off the terminal ends.
For purposes of illustration, we have in FIGS. 4 and 4A a single
blood vessel 30b having a wall 31b with a terminal portion 33b
terminating in an end surface 32b, the latter in engagement with
the working surface 16b of the tool member 13b which is being
ultrasonically vibrated in the direction 23b.
At the interface of the working surface 16b and terminal surface
32b we have a transmission of both rubbing forces and mechanical
vibrational energy to the blood vessel 30b which results in a
localized heating of the terminal portion 33b. FIG. 4A illustrates
the contour of the surfaces in engagement with each other and the
transmission of the shear waves over the distance D. The pressure
applied with the tool member, partially determines the degree of
shear waves and rubbing vibrations transmitted to the terminal
portion 33b of the blood vessel for a given textured tool. At point
P.sub.1 shear vibration is developed in the tissue 31a, then at
P.sub.2 the shear vibration has dropped almost to zero whereby the
shear vibration energy is converted into heat in the tissue of the
blood vessel. The smallness or minimal depth of penetration of
P.sub.1, P.sub.2 is what makes for quick healing and cauterizing
action of the tool member.
The shear wave pattern 35b extends the distance D, which is the
distance from P.sub.1 to P.sub.2, along the blood vessel 30b to
obtain the localized heating of the terminal portion. The coupling
action at the working surface 16b and blood vessel 30b is enhanced
by the application of the small compressive force, as indicated by
arrow 36b, in a plane substantially normal to the plane defined by
said terminal end surface 32b. At P.sub.1 in addition, to the
extent that shear vibration is not induced in the tissue, there
will be a slippage and a frictional rubbing action which will also
produce heat practically instantaneously at P.sub.1. It is a
combination of these effects which create the closure at the
terminal portion of the blood vessel.
It will be appreciated that the relative amounts of shear vibration
and frictional rubbing action will be determined or selected by the
magnitude of the tool vibration and the tool surface in relation to
the tissue surface. Many combinations are possible whereby either
the frictional or the shear components may be emphasized.
The extent that the rise in temperature occurs at the terminal
portion 33b of the blood vessel 30b is related to the rubbing
vibrations applied and this is related to the peak speed which
is:
V peak = 2.pi.f A
a = peak amplitude
f = frequency
V = peak velocity
So that if f is raised, A is lowered and we can retain the same
peak speed at all frequencies. This is why the more rubs per second
the higher the frequency for the same output peak speed.
Accordingly the working surface 16b of the tool member 13b may be
surface finished for sufficient roughness to allow increased
friction against the tissue. This is quite different from a
standard knife or scalpel which has polished sides.
The thickness of the tool member should also be held to a minimum
so as to permit a more rapid local temperature rise which is
attributable to the shear production and absorption in the adjacent
tissue and the temperature rise due to rubbing of tissue surface,
which involves slippage between tool member and tissue surfaces. We
can say that during the to and fro motion, neglecting the energy of
cutting itself, when a knife is used we have:
Ultrasonic energy per stroke = Ultrasonic shear energy produced per
stroke + Frictional rubbing energy per stroke.
Since, in both cases the energy absorbed goes into superficial
heating of tissue and cutting tool, we can estimate the effects by
considering all the energy to be frictional for ease of making
approximate calculations.
Assuming an average force of friction, F, we have the power
dissipated superficially at a tool tissue interface equal to:
S = stroke
F = average friction force
P = power
P= fFS= (Fv max.)/.pi.
Now V max. for a frequency of 20 kc./s. and a stroke of 0.010 inch
is approximately 50 f.p.s. Therefore P is approximately 15 watts,
when F is between one-half and 1 pound. Since this power is
dissipated in superficial supreficial region of the cutting, the
heat capacity of the tissue and the tool are quite small. For
example for a steel tool of dimension 1.times.0.125.times. 0.10
inch the total heat capacity is only a few hundredths of a gram. In
such a case it is possible to obtain local temperature rises of the
order of hundreds of degrees centigrade under the condition
outlined above. This is ample to stop "ooze."
Accordingly the frequency and amplitude of vibration of said tool
member is selected at a level wherein the transmitted shear waves
are substantially maintained at the terminal portion 33b with only
superficial penetration and heating of the remainder of the blood
vessel 30b.
Accordingly, the frequency and amplitude of vibration is preferably
selected at a level to provide a peak velocity of at least 10 feet
per second along the working surface 16b of the tool member 13b and
more generally the general range of approximately 40 feet per
second to 100 feet per second.
FIG. 4B shows a portion of the biological organism 25b with an
outer layer of skin 26b and a plurality of blood vessels 30b
extending through the cellular structure 27b and terminating
against the working surface 16b of the tool member 13b. The tool
member 13b is being vibrated at an ultrasonic rate in the direction
of arrow 23b, which is in a plane substantially parallel to the
plane defined by the terminal end portions 33b, to induce shear
waves 35b, which penetrate the blood vessels 30b and surrounding
tissue structure 27b. The high-frequency vibration and amplitude of
the tool member is selected to obtain only a superficial
penetration and resulting heating of the terminal portions 33b so
that there is a minimum of damage to the underlying tissue area 31b
and all of the blood vessels are simultaneously closed off.
As illustrated in FIGS. 4C and 4D the terminal portion 33b has an
end surface 32b that defines a plane 37b that may vary in angular
relationship to the axis of the blood vessel 30b. In practice the
angular engagement between the working surface 16b of the tool
member 13b and the end surface 32b may not always be controlled
during a surgical procedure since the blood vessels such as
capillaries, veinules, veins, arterials and arteries extend in
various directions throughout the body. The important consideration
is that the ultrasonic longitudinal mechanical vibrations, as
indicated by arrow 23b, are applied having a major component of
vibration parallel to the terminal plane 37b and a component of
compressive force, as indicated by arrow 36b, in a plane
substantially perpendicular to the terminal plane 37b.
FIGS. 5, 5A, 5B, 5C, 6, 6A, 7 an 7A illustrate the actual surgical
procedure in vivo of obtaining a closure at the terminal portion of
a blood vessel using the ultrasonic instrument illustrated in FIG.
2, or a tool member illustrated in FIGS. 4, 4A and 4B. As explained
with respect to the theory of the present invention in FIGS. 3, 3A,
3B, 3C and 3D the degree of shear waves and frictional rubbing may
be controlled so that a predominant reliance on one or the other is
produced.
In FIGS. 5, 5A, 5B and 5C the terminal closure 40c is formed
primarily by producing a plastic flow of the wall of the blood
vessel and containing the flow for a period of time sufficient to
obtain a joining of the severed ends together. Initially the
cutting edge 15c of the tool member 13c is placed in engagement
with the skin 26c of the body 25c and the tool member 13c is
ultrasonically vibrated and a small compressive force in the
direction of arrow 36c is applied to obtain a cutting of the skin
26c and progressively sever the tissue by a continued movement of
the cutting edge 15c through the cellular material 27c until the
wall 31c of the blood vessel 30c is engaged. The wall 31c for
purposes of discussion is considered as layers of tissue 42c and
43c, respectively.
As seen in FIG. 5A after the cutting edge 15c severs the tissue
layer 42c a certain amount of blood 44c flows from within the blood
vessel 30c into the opening 45c that has been formed. As the
movement of the ultrasonic instrument is continued downwardly we
have the engagement of the working surface 16c with the terminal
end portion 33c of the blood vessel to apply a compressive force to
the end surface to obtain a localized heating of the terminal
portion by the application of the ultrasonic mechanical vibration.
The relative movement is continued so that the application of the
mechanical vibrations are transmitted for a period of time
sufficient for the localized heating to form the closure 40c at the
terminal portion 33c. In this manner the terminal portion 33c is
closed off by the formation of the closure 45c and the blood
contained therein is prevented from escaping through the closure.
The closure 45c is produced at least in part by the production of
said shear waves and their conversion into heat coupled with the
localized heating obtained by inducing frictional rubbing at the
terminal portion 33c. The extent of each factor will vary with the
texture of the working surface 16c and the degree of the
compressive force applied by the working surface against the
terminal portion.
FIG. 5D is an enlarged microscopic examination of the blood 44c and
as illustrated the blood contains red corpuscles 46c, white
corpuscles 47c and platelets 48c, the latter play an important role
in the natural clotting of blood by producing fibrin when exposed
to air. This natural clotting ability of blood is relied upon at
least in part with respect to the formation of the closures
illustrated in FIGS. 6, 6A, 7 and 7A.
FIGS. 6 and 6A illustrate the formation of the closure which is
substantially formed by clotting of the blood at the terminal
position. The working surface 16d is placed in engagement with the
layers of wall 42d and 43d of the blood vessel 30d, which is of a
size in the capillary range, with the blood 44d contained therein.
The tool member 13d preferably has a textured surface to permit air
and most importantly oxygen to be delivered past the layer of skin
26d to the terminal portion 33d of the blood vessel to obtain a
clotting action. The tool member 16d acts as an ultrasonic pump and
stimulates the flow of air to the worksite. As the air reaches the
worksite we have the additional action of the conversion of the
ultrasonic mechanical vibrations to obtain a localized heating by
the conversion of the frictional motion into heat and the localized
heating expediates the formation of the blood clot 50d which forms
the closure 40d. Since the blood vessel is relatively small in
diameter we have the formation of the closure 40d that is
substantially formed by a clotting of the blood 44d therein. As
seen in FIG. 6A the tool member is then removed leaving the opening
of wound 45d and closures 40d formed on each respective end of the
severed blood vessels.
FIGS. 7 and 7A illustrate the formation of a closure 40e by
partially closing the layers 42e and 43e of the wall 31e of the
blood vessel 30e at the terminal portions 33e by the localized
heating and the remainder by forming a blood clot 50e of the blood
44e contained in the reduced area of the blood vessel. The
ultrasonic tool member 13e transmits the mechanical vibration which
produces a plastic flow of the wall 31e of said blood vessel which
flow is continued for a period of time to obtain a reduced
cross-sectional area and during which same period of time the
localized heating assists in the formation of the blood clot 50e
which together with the reduced area forms the closure 40e to
prevent the blood from escaping therefrom. The tool member is then
removed past the skin 26e leaving the opening 45e.
It is appreciated that the process although illustrated for a
single blood vessel can be occurring simultaneously on a plurality
of blood vessels. To increase the rate at which the closure is
formed and reduce healing time the working surface of the tool
member may be heated to a temperature level which is above room
temperature, but below a temperature that would normally sear the
terminal portion of the blood vessel. The temperature of the tool
may be heated in any conventional manner, as for example, in
accordance with U.S. Pat. No. 3,321,558.
There are instances in surgical procedures where it is desirable to
be able to stop bleeding independently of having previously cut the
tissue of the body. As for example, in gunshot wounds and other
accidents it is often desirable to stop bleeding and accordingly
spatulalike tools in accordance with the present invention may be
utilized.
FIGS. 8 and 8A illustrate one form of readily replaceable
implement, in the form of a spatulalike tool member 13f, having a
body portion 28f with substantially flat parallel working surfaces
16f that have been textured to a preselected micro finish to
provide means for coupling the ultrasonic vibrations to the
terminal portions of the blood vessels. The surface finish is
selected for the transmission of rubbing vibrations and shear waves
to obtain the localized heating. One end of the spatula body
portion 28f is fixedly secured to the base portion 21f, and the
latter has a threaded stud 20f for securement to the ultrasonic
driving member. The base portion 21f is preferably of a metallic
material capable of supporting ultrasonic vibrations and adapted to
be set into vibration in a given direction at ultrasonic
frequencies. The body portion 28f may be in the order of 0.010 to
0.160 inches thick and be concave in configuration for strength
reasons. It may also be designed to vibrate elliptically to permit
intermittent separation of the tool member and terminal portions to
promote the flow of air to the terminal portions for clotting. The
obtainment of elliptical vibration for vibratory elements is well
known in the art, for example, as illustrated in U.S. Pat. No.
2,990,916 in which applicant is a coinventor thereof.
As illustrated in FIG. 9 the spatulalike tool member is illustrated
for surgical procedures in which it is desired to form closures at
terminal ends of blood vessels 30g separately from when the actual
cutting is performed. Accordingly the spatulalike tool 13g is
inserted within the opening 45g of the body 25g such that the
working surface 16g of the tool member 13g applies a compressive
force against the terminal portions 33g of the severed blood
vessels. The compressive force is applied in the direction of arrow
36g. The tool 13g is simultaneously vibrated, in a direction as
indicated by arrow 23g, and at an ultrasonic rate to transmit
mechanical vibrations to the terminal portion 33g of the blood
vessels to obtain a localized heating of at least some of the
terminal portion. The application of said compressive force and
mechanical vibrations are continued until a closure at the terminal
portion is formed and the blood contained therein is prevented from
escaping through the formed closure. The thickness of the spatula
tool member 13g may be narrower, as illustrated in FIG. 9, than the
opening 45g in the body, such that only one surface 16g engages the
severed blood vessels. If desired the width of the spatula body 28g
may be substantially equal to that of the body opening 45g so that
both terminal ends 33g of a respective blood vessel 30g is closed
during one insertion of the tool member within the wound.
The localized heating to obtain the closures may be induced by
frictional rubbing at the terminal portion 33g of the blood vessel
30g so that the closure is produced at least in part by frictional
heating. By providing a textured surface to the tool member 13g the
rate of frictional heating may be controlled when combined with the
other factors to produce the terminal closure. Depending upon the
thickness of the spatula tool member either pure longitudinal
vibration will be obtained or a flexural component of motion, as
indicated by the arrow 51g, so as to obtain elliptical vibrational
motion along the working surface 16g. This permits intermittent
disengagement between the wall surface or terminal end of the blood
vessel 33g and the working surface 16g so that air and in turn
oxygen may be continuously supplied to the work site to assist in
the clotting of the blood.
FIGS. 10 and 11 illustrate one form 10h of the ultrasonic system
for joining together in vivo, overlapping layers of organic tissue.
The system includes a hand held instrument including an ultrasonic
motor 11h, which may be the type as discussed with reference to
FIG. 2, and include a tool member 13h having an enlarged portion
53h terminating in a working surface 16h that extends in a plane
substantially normal to the direction of mechanical vibrations
illustrated by the arrow 23h. The base 21h of the tool member 13h
is secured to the insert portion 17h. Support means 55h is provided
to act as an anvil or clamp so that the overlapped layers of tissue
42h and 43h of the wall 31h of the blood vessel 30h may be
compressed between the vibratory working surface and a support
surface.
The support means 55h includes a pair of legs 56h and 57h
respectively, secured together at their lower end by bands 58h and
provided with gripping means in the form of individual lugs 59h
that extend outwardly from the upper end of the legs for engagement
by the fingers of the surgeon or operator 12h in a manner
hereinafter described. The leg 57h has a lower extension 60h that
terminates in a support arm 61h at substantially right angle to the
extension 60h, and is provided with a support surface 62h in spaced
relation to the working surface 16h of the tool member 13h.
The legs 56h and 57h are in spaced relation to each other and may
be contoured to conform to the cylindrical configuration of the
ultrasonic transducer housing 14h. The generator 18h is connected
to the transducer 11h by means of cable 19h in a conventional
manner. As seen in FIG. 10 the cable 19h may enter the ultrasonic
motor 11h from the side so as to leave the rear end 63h free for
engagement by the thumb or any other finger of the surgeon to
permit manual control of the relative displacement between the
overlapping working and support surfaces.
The support means 55h is mounted for relative movement, with
respect to the ultrasonic motor 11h by providing a pair of slots
65h on each of the legs 56h and 57h, and which slots accept headed
fasteners 66h which extend from the casing 14h through the slots
65h to permit free relative movement between the ultrasonic motor
11h and support means 55h. The lower end of the casing 14h is
provided with an annular shoulder 67h which is adapted to receive
spring means in the from of a spring 68h which is contained within
the shoulder 67h at one end thereof and in engagement with the
bands 58h at the opposite end thereof. The spring 68h applies a
force in the direction of arrow 68h, so that the working surfaces
of the support means and ultrasonic motor means are biassed away
from each other whereby the force applied by the surgeon is
required to bring the overlapping working and support surfaces
together. If desired the spring may be coupled to the support and
ultrasonic motor means so as to force them together with a
predetermined static force which might be varied in a conventional
manner not shown. In this manner once the static force is
determined for the particular thickness of tissue the resultant
permanent or temporary seal may be obtained. Accordingly the spring
means may yieldably urge the support means 55h and transducer means
11h relative to each other to a position wherein the working and
support surfaces 16h and 62h, respectively, are normally in
engagement with each other under a predetermined static force, so
that the support and transducer means are first separated for the
placement of the layers of tissue 42h and 43h therebetween. In
contrast to this the spring means may be adjusted such that the
working and support surfaces are normally maintained in spacially
fixed relation to each other, so that the layers 42h and 43h are
positioned between the surfaces which are brought together by the
operation of the hand held instrument.
As previously explained during surgical procedures it becomes
necessary to tie-off veins and arteries so as to prevent the flow
of blood therethrough. In accordance with the invention the joining
of the walls may be of a permanent or semipermanent nature, and
this is accomplished by properly selecting the frequency and
amplitude of ultrasonic mechanical vibrations to produce an optimum
flow of the collagenous elements contained in the overlapping
portions of tissue. This collagenous material is similar to that
normally found in the formation of scar tissue. In practice the
ultrasonic instrument 10h may be employed to join together, at a
select area the wall of a blood vessel and as seen in FIG. 10 the
wall 31h may be considered to include the overlapping layers of
tissue 42h and 43h.
As seen in FIGS. 12, 12A and 12B we have the blood vessel 30h
exposed within an opening 45h within the organic body 25h. To
produce a joining of the overlapping layers of wall tissue 42h and
43h respectively, the arm 61h of the support means 55h is placed
beneath the blood vessel 30h and the working surface 16h of the
tool member 13h is brought into contact with the layer of tissue
42h. The working and support surfaces 16h and 62h are moved
relative toward each other until the blood vessel 30h has the
overlapping layers of tissue 42h and 43h in contact with each other
as seen in FIG. 12A. Simultaneously therewith a small compressive
force, in the direction of arrow 36h, is applied to the layers of
tissue traversing the area of overlap.
The working surface of the tool member 13h is vibrated at an
ultrasonic rate, as for example, in the frequency range of from 15
kc./s. to 100 kc./s. and preferably in the range of 20 kc./s. to 40
kc./s., so as to apply an additional recurring force to the
overlapped layers of tissue, and produce a superficial heating at
the interface of the overlapped layers. The vibrational force has a
substantial component of vibration normal to the overlapped
surfaces, as indicated by the arrow 23h. The frequency of the
ultrasonic rate of vibration is selected in the above frequency
range so as to preferably also produce an optimum flow of the
collagenous elements in the overlapped layers of tissue. The energy
is then continually applied until a closure or bond 40h is formed
between the collagenous elements in the overlapping layers of
tissue, as seen in FIG. 12B, and the blood is prevented from
flowing past the closure. The closure 40h may be of a temporary
nature or permanent one depending upon the proper control of the
vibratory energy and static force to fuse together the
superficially heated interface.
For certain applications it is desirable to join together the
overlapping layers of tissue and at the same time cut off the
excess material. As illustrated in FIG. 12C the support arm 61j is
provided with a cutting edge 70j and as the overlapped layers of
tissue 42j and 43j are compressed between the working surface 16j
and support surface 26j and joined together by the energy
transmitted through the tool member 13j and the excess tissue
layers 71j and 72j are cut off. If desired the cutting edge may be
placed on the working surface 16j of the tool member 13j.
For those applications in which it is desired to intermittently
join together overlapping layers of tissue we have the apparatus
illustrated in FIG. 12D. The overlapping layers of tissue 42k and
43k are first clamped together by clamping means 75k which includes
clamping members 76k and 77k which may form part of the ultrasonic
instrument or may be the forward portion of a pair specially
designed clamping instrument. The clamping means 75k is applied in
close proximity to the area of overlap of the layers of tissue 42k
and 43k to be joined together. The ultrasonic instrument 10k
includes the support means 55k for engaging one side of the
overlapped layers of tissue and which opposite side is engaged by
the tool member 13k which as illustrated is provided with a
circular working surface. By intermittently moving the ultrasonic
instrument along the area of overlap a number of closures or bonds
30k, such as stitches may be formed.
While the invention has been described in connection with
particular ultrasonic motor and tool member constructions, various
other devices and methods of practicing the invention will occur to
those skilled in the art. Therefore, it is not desired that the
invention be limited to the specific details illustrated and
described and it is intended by the appended claims to cover all
modifications which fall within the spirit and scope of the
invention.
* * * * *