U.S. patent number 3,794,039 [Application Number 05/083,740] was granted by the patent office on 1974-02-26 for apparatus for cryosurgery.
This patent grant is currently assigned to Linde Aktiengesellschaft. Invention is credited to Ewald Duczek, Paul Kollner.
United States Patent |
3,794,039 |
Kollner , et al. |
February 26, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
APPARATUS FOR CRYOSURGERY
Abstract
An apparatus for cryosurgery wherein the probe includes a grip
member having a hollow cryogenic coolant feed line supported by
said grip member open at the tip thereof and connected at one end
to the cryogenic coolant supply for transmitting coolant to impinge
directly upon the tissue to be frozen. A return line open at the
tip thereof and concentrically disposed around the feed line forms
a space therebetween, with means communicating said space to
suction means for returning vaporized coolant from the feed supply
line. The open end of the feed supply line is recessed with respect
to the corresponding open end of the return line, allowing a
cryogenic coolant to impinge directly upon the tissue to be frozen,
while vaporized coolant is returned through the return line.
Inventors: |
Kollner; Paul (Wolfratshausen,
DT), Duczek; Ewald (Wolfratshausen, DT) |
Assignee: |
Linde Aktiengesellschaft
(Munich, DT)
|
Family
ID: |
5749241 |
Appl.
No.: |
05/083,740 |
Filed: |
October 26, 1970 |
Foreign Application Priority Data
|
|
|
|
|
Oct 25, 1969 [DT] |
|
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P 19 53 835.3 |
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Current U.S.
Class: |
606/22;
62/293 |
Current CPC
Class: |
A61B
18/0218 (20130101) |
Current International
Class: |
A61B
18/00 (20060101); A61B 18/02 (20060101); A61f
007/00 (); A61b 017/36 (); F25d 003/10 () |
Field of
Search: |
;128/303.1,240,276,65,66,241,256,257,400 ;62/293 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Pace; Channing L.
Attorney, Agent or Firm: Millen, Raptes & White
Claims
What is claimed is:
1. In an apparatus for cryosurgery having a central unit containing
a supply of liquid cryogenic coolant, control and regulating means,
and subatmospheric suction means connected to a probe for feezing
tissue, the improvement comprising:
a. a cryogenic probe including a grip member having a hollow
cryogenic coolant feed line supported by said grip member, said
line being open at the tip thereof and connected at one end to said
cryogenic coolant supply for transmitting liquid coolant to impinge
directly upon tissue to be frozen;
b. a hollow cryogenic coolant return line open at a transparent end
thereof concentrically disposed around said feed line to form a
space therebetween; and
c. means communicating said space to said subatmospheric suction
means for returning vaporized coolant from said feed line, the open
end of said feed line being recessed with respect to the
corresponding open end of said return line.
2. Apparatus according to claim 1, wherein said return line is
provided with a vacuum jacket therearound at least in the portion
thereof most proximate said one end of said feed line.
3. Apparatus according to claim 1, wherein said second line
comprises two portions telescopically mounted with respect to one
another.
4. Apparatus according to claim 3 wherein the portion of said
return line most proximate the free end of said first line is
transparent acrylic.
5. Apparatus according to claim 4, wherein the portions of said
return line are sealed with respect to one another by "O" ring
seals.
6. Apparatus according to claim 1, wherein said return line is
connected to a detachable portion of said grip member.
7. Apparatus according to claim 1, wherein heating means are
disposed to raise the temperature of returning vaporized
coolant.
8. Apparatus according to claim 7, further comprising thermostatic
control means for said heating means.
9. Apparatus according to claim 1, wherein a fluid supply
communicates said feed line with said supply of cryogenic coolant
and wherein a valve is disposed in said fluid supply to control
flow of coolant therethrough.
10. Apparatus according to claim 9, wherein said valve has a
valving member formed to meter flow thereby as a function of the
displacement thereof.
11. Apparatus according to claim 10, wherein said valving member is
spring loaded to normally block flow therepast and which can be
lifted by excess pressure to serve as a pressure release.
12. Apparatus according to claim 1, wherein said grip member
comprises a sectionalized housing which can be readily
disassembled.
13. Apparatus according to claim 12, wherein said grip member is
provided with a handle having a trigger thereon.
14. Apparatus according to claim 13, wherein a connection line
detachably connects said grip member to said central supply
unit.
15. Apparatus according to claim 13, wherein means are provided to
simultaneously operate a valve controlling the coolant supply and
said suction means in said central supply unit and to regulate flow
through said valve in said feed line by actuation of said
trigger.
16. Apparatus according to claim 14, wherein said connection line
comprises plural concentrically arranged corrugated pipes
detachably coupled to said central supply unit.
17. Apparatus according to claim 16, wherein the space between the
innermost of said pipes is evacuated, and wherein electric control
lines are disposed through the space between the outermost of said
pipes.
18. Apparatus according to claim 1, wherein heating means are
disposed on the end of said return line corresponding to the free
end of said first line.
19. In a process for freezing tissue with a cryogenic probe by
passing a liquid cryogenic coolant through a hollow feed line open
at an end thereof and recessed with respect to a corresponding open
end of a hollow return line concentrically surrounding said feed
line to vaporize said coolant directly upon tissue to be frozen,
the improvement which comprises:
returning vaporized coolant by subatmospheric suction from said
feed line through said return line.
20. A process according to claim 17, further characterized by:
a. placing a front rim of said return line on the tissue to be
frozen; and
b. drawing the tissue to be frozen against the rim of said return
line by suction prior to passing said coolant onto said tissue to
be frozen.
21. A process according to claim 19 wherein said return line is
transparent, further comprising observing the amount of coolant
which is in the liquid phase at the site of application.
22. A process according to claim 21 further comprising regulating
said coolant feed responsive to said observation.
23. An apparatus according to claim 1 further comprising a pressure
relief safety valve responsive to excess coolant pressure.
24. An apparatus according to claim 18 wherein said heating means
includes an annular heating device around the open end of said
return line.
25. An apparatus according to claim 1 further comprising
d. a pressure relief safety valve responsive to excess coolant
pressure; and
e. an annular heating device around the open end of said return
line.
26. A cryosurgical instrument adapted for use in the freezing of
tissue comprising:
means for providing a confined volume including and surrounding at
least a portion of the tissue to be frozen;
means for filling said confined volume with liquified gas coolant
in liquid form to a level above the level of tissue to be
frozen;
means for drawing the tissue to be frozen against said means for
providing a confined volume; and
means for venting vapors of said coolant from said confined volume
above said level of liquid.
27. An instrument according to claim 26 wherein said means for
venting coolant vapors is a subatmospheric suction means.
28. The instrument according to claim 26 wherein said walled
structure comprises a generally cylindrical wall having an axis
extending in at least one direction.
29. The instrument according to claim 26 wherein said means for
providing a confined volume is transparent.
30. A cryosurgical instrument for freezing of tissue
comprising:
an open walled chamber for providing a confined volume including
and surrounding at least a portion of the tissue to be frozen;
means including a vent tube having a coolant delivery tube disposed
coaxially therewith for directing a flow of liquified gas coolant
toward tissue to be frozen within said confined volume and for
venting vapors of said coolant from said confined volume, said open
walled chamber being fastened to the outer one of said tubes;
and
subatmospheric suction means capable of drawing the tissue to be
frozen against a rim of said open walled chamber.
31. The instrument according to claim 30 wherein said means for
venting coolant vapors is a subatmospheric suction means.
32. The instrument according to claim 30 wherein said open walled
chamber is transparent.
33. The cryosurgical instrument according to claim 30 wherein said
outer tube and said chamber are adapted to releasably engage one
another, whereby said chamber may be removed from the end of said
tube.
34. A cryosurgical method which comprises
positioning one open end of an annular containment shield against
the tissue to be frozen with sufficient subatmospheric suction
force to form a hermetic seal thereat;
directing a flow of cryogenic liquid through the shield toward said
one end into contact with the tissue to be frozen and vaporizing
liquid thereat;
venting the vaporized liquid upstream of said one end;
and maintaining the hermetic seal until the tissue has been frozen
and the liquid has been vaporized.
35. A method according to claim 34 wherein said vaporized liquid is
vented by subatmospheric suction.
Description
BACKGROUND OF THE INVENTION
Conventional cryosurgical devices of the type to which this
invention pertains have probes which are sealed at the tip. In use,
the ordinarily solid front end of the probe is brought into contact
with the tissue to be subjected to low-temperature treatment. The
coolant, normally liquid nitrogen, is introduced into the tip of
the probe by means of a feed line, vaporized at that point, and
returned to the central unit by means of a return line, or released
into the atmosphere from the probe.
Such cryosurgical devices exhibit a disadvantage in that it is
normally difficult to adapt the tip of the probe to the contour of
the tissue to be treated, especially when projecting and strongly
fissured proliferations are involved. One possibility of avoiding
this disadvantage resides in maintaining probes of various sizes
and shapes in readiness. However, this is very cumbersome and
expensive and does not meet all situations occurring in
practice.
SUMMARY OF THE INVENTION
Consequently, this invention provides a novel cryosurgical device,
the probe of which does not have the above-mentioned disadvantages
and which can furthermore be exchanged in a simple manner with
probes of a different type of construction connected to a central
supply unit.
This problem is solved by providing a feed supply line and return
line which are open at the tip of the probe. This makes it possible
for the coolant to impinge directly upon the tissue. In accordance
with a special embodiment of the invention, the probe tip consists
of two concentric tubes, wherein the front end of the inner tube is
recessed with respect to the front end of the outer tube. Thereby,
a chamber is produced within the outer tube which can be filled by
the coolant fed by the inner tube. Accordingly, when such a probe
is applied to the tissue to be treated, only the rim of the outer
tube need be in contact with the tissue, and the surface of the
tissue to be treated is completely under the effect of the coolant,
independently of the shape of the tissue. In accordance with a
further development of the invention, the inner tube exhibits a
vacuum jacket at least in the rear section thereof. This prevents
outside heat from contacting the coolant, which would result in an
undesired cooling of the entire device and an unnecessary
consumption of coolant.
The grip member can consist of a preferably sectioned housing and
can be provided with a handle exhibiting a trigger. The grip member
can be detachably connected by a connection line to a central unit.
In this case, it is possible to attach different-type grip members
with probes to a suitable connection line.
The connection lines between the grip member of the probe and the
central unit are preferably concentrically arranged corrugated
tubes detachably joined to the central unit by means of a coupling
section.
An arrangement of this kind of connection lines for the supply of a
probe with a coolant is disclosed for example in the U.S. Pat. No.
3,220,414.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional details and advantages of the invention can be derived
from the embodiment schematically illustrated in the drawings,
illustrating the probe in a partially sectional view.
FIG. 1 is a schematic view, partially in cross-section, of a probe
of this invention;
FIG. 2 is a cross-sectional view of a probe having a conventional
trigger, valving member and control means incorporated therein;
and
FIG. 3 is a cross-sectional view of a probe illustrating a
corrugated connection line and electrical control lines.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A tube 1, preferably consisting of stainless steel, serves as the
feed line for the coolant which is preferably liquid nitrogen; this
tube 1 is surrounded, in its rear portion, by a vacuum jacket 2, by
means of which cold losses and thus a premature warming and
evaporation of the coolant are avoided. The vacuum jacket 2 can be
evacuated by the disconnectable nipple 2a. The front end of the
feed tube 1 consists of a solid metallic part 3 which is likewise
normally made of stainless steel. A return tube 4 is arranged
concentrically about the feed tube 1 with vacuum jacket 2; this
return tube is fixedly joined in the rear section with the probe
shank 5, which latter consists preferably of
polytetrafluroethylene, and the front end of the return tube
exhibits a mounting 6, provided with openings, for the feed tube 1.
A return tube sleeve 7, preferably consisting of transparent
acrylic and sealed by "O" rings 8, is displaceably arranged on the
tube 4, which latter is likewise made preferably of
polytetrafluoroethylene.
By telescopic movement of the return tube sleeve 7 the free space
present in the outer end can be reduced or enlarged, and the
distance between the point of exit of the coolant from the tube 1
and the tissue to be treated can be varied. Due to the fact that
the outer return tube sleeve 7 consists of a transparent material,
it is possible for the operator to closely observe the processes in
the probe, in particular to determine the amount of coolant which
is still in the liquid phase and has not yet evaporated at the site
of application.
An electric heating element 10 is disposed in the probe shank 5
within a metallic jacket 9, which element serves for heating the
recycled coolant to room temperature. This element is preferably
thermostatically controlled. The thermostat for this device (not
shown) can be arranged directly behind the heating device in the
grip member 12, or at some other place in the return line, for
example within the central unit.
The tube 4, according to a further embodiment of the invention, is
mounted to a hollow-cylindrical shank of a larger diameter
detachably joined to the grip member 12, preferably, by means of a
threaded section 11, facilitating the exchangeability of the tip of
the probe. This exchange possibility is of particular advantage,
since, on the one hand, when the tip of the probe has been damaged,
only the tip need be replaced, and, on the other hand, when probe
tips of different lengths and different thicknesses are required
for different purposes of application, only the probe need be
interchanged.
The grip member 12 is composed of two parts 12a and 12b and can be
disassembled along the parting line 13 after the release of
fastening elements (not shown). This facilitates the servicing and
repair of the elements contained in the grip member. The grip
member 12 is provided with a handle 14 in which a trigger 15 is
installed. Furthermore valve 16 is disposed in the grip member,
which valve is mechanically connected with the trigger 15 and can
be operated by means of the latter. This valve can have a cone
valving member of conventional design which serves as a metering
valve when lifted mechanically. The valve member can furthermore be
fashioned so that it can be lifted against the force of a spring by
the excess pressure of the coolant. In this case, the valve has the
effect of a safety valve in the feed line for the coolant.
By means of a screw cap 17, the outer part of a connection line is
detachably connected with the rear part 12b of the grip member 12.
The feed line for the liquid coolant, for example, liquid nitrogen,
consists of a corrugated pipe 18, preferably made of stainless
steel, surrounded by another corrugated pipe 19 of the same
construction, but having a larger diameter. Between the two pipes
there is an evacuated space 20. Yet another corrugated pipe 21 is
arranged concentrically and in spaced relationship to the
corrugated pipe 19. The pipe 21 consists of a soft resilient
material such as plastic and is supported by a coil spring.
Together with the corrugated pipe 19, the pipe 21 forms an annular
duct 22 of a relatively large cross-section for the gaseous coolant
flowing back to a central unit (not shown) which coolant is warmed
approximately to room temperature. This coolant is taken in by a
suction fan (not shown) arranged in the central unit. The space 20
is evacuated in order to prevent the transfer of heat thereto, and
electric lines (not shown) are installed in the duct 22 between the
outer corrugated tubes wherein the warmed returned gas is flowing.
The connection lines terminate in a coupling section detachably
joined to the central unit.
In accordance with a particularly advantageous embodiment of the
invention, provision is made for simultaneous operation by the
trigger 15 of a check valve for the coolant and the suction fan
disposed in the central unit, as well as for regulation of the
metering valve 16 in the grip member. By means of providing the
trigger 15 with several functions, it is possible, by an initial,
slight depression of the trigger, first to open the check valve in
the central unit and to actuate the suction fan. Next, by further
depression of the trigger 15, opening of the metering valve is
effected corresponding to the extent of such depression.
In FIG. 2 an inlet portion 1a and an outlet portion 1b of feed tube
1 can be seen which are in communication with one another via inlet
chamber 23a and outlet chamber 23b. The inlet chamber 23a is sealed
against the inner part of handle 14, while using a corrugated pipe
24 welded to valve body 36 and to valve stem 25. When trigger 15 is
pressed into the inner part of the handle 14 against the force of a
spring 26, one or more microswitches 27 are first activated and
valve stem 25 is then lifted against the force of spring 28. The
microswitches 27 can operate relays, valves, or the suction fan in
the central supply unit as desired. When valve stem 25 is lifted, a
valve cone 29 is simultaneously lifted from a valve spring seating
30, and liquid nitrogen passes from inlet portion 1a through inlet
chamber 23a to outlet chamber 23b and thence through outlet part
1b. Centering means 31 allows a centered lifting of valve cone 29
against spring 28 which is held in a turnable valve cup 32, with
which the force of spring 28 can be regulated. Valve 16 is
surrounded by an evacuated chamber 2. Trigger 15 and microswitches
27 are mounted on a mounting plate 33 which can be welded to valve
body 36. Electric lines 34 coming from the microswitches 27 and
going to the central supply unit can have a plug connection 35 at
each side of the connection line and are spirally wound around a
corrugated pipe 19.
FIG. 3 shows one coupling system between grip member 12 and the
connecting line, which may also be used as a coupling system
between the connecting line and the central supply unit.
Conventional corrugated pipes 18 and 19 form an evacuated space 20,
in which there is a spirally wound spacer 40, conveniently of
plastic material, to maintain the distance between the corrugated
pipes 18 and 19. At the end of corrugated pipe 18 is welded a part
44, while at the end of the corrugated pipe 19 is welded a part 37;
both parts 44 and 37 are welded together to sealingly enclose one
end of evacuated space 20. In the open end of part 37 there may be
fitted an O-ring seal 38. Corrugated pipe 21 is formed of a plastic
tube fitted with a spring coil 45. An annular duct 22 is formed
between corrugated pipe 19 and corrugated pipe 21, the latter being
surrounded by a fitted screw cap 17 with a sealing device 42.
Within the annular duct 22 electric lines 34 are spirally wound
around the corrugated pipe 19. These electric lines 34 can be
connected to an electric system in either the grip member 12 or the
central supply unit by means of plug connections 35 such as shown
in FIG. 2. In fitting the connecting line to the grip member 12,
parts 44, 37, 38 are slid onto parts 43 and 39 of valve 16. The
corrugated pipe 21 is turned into the space between grip member 12b
and part 41, fixed by means of screw cap 17, and sealed by sealing
device 42.
Since the tissue to be treated can freeze to the front rim of the
outer tube during the cold treatment, an annular heating device 23
is provided which is firmly connected to the front rim of the
return tube sleeve 7 or can be placed thereon; this heating device
is operable by means of a push button 24 likewise disposed in the
handle 14. In this manner, it is possible to remove the tip of the
probe, frozen fast to the tissue to be treated, in a rapid and easy
fashion. The feed lines for this heating device can also be laid
within the flow path for the returning gas.
The mode of operation of the device of this invention is as
follows:
First of all, the probe is firmly placed on the tissue to be
treated with the front rim of the outer return tube sleeve 7. Then,
by actuation of the trigger 15, an electric circuit is initially
closed, which circuit opens a magnetic valve (not shown) in the
central unit, whereby pressurized liquid nitrogen is conducted
through the corrugated pipe 18 to the valve 16 in the grip member
12. At the same time, the suction fan provided in the central unit
is started, whereby the tissue to be treated is drawn against the
rim of the outer return tube sleeve 7 and somewhat into this tube.
Upon a further depression of the trigger 15, the cone valve member
of the valve 16 is lifted, by means of a suitable mechanical
transmission (not shown) in dependence on the extent to which the
trigger 15 is depressed. Thereby, the liquid coolant can pass
through the feed tube 1 and can exit through the front end 3
thereof, and impinge on the tissue to be treated. The return tube
sleeve 7 can be telescopically moved on the tube 4 at any time to
adjust the proximity of the tip of the tube 1 to the tissue as
desired. The largest portion of the thus-supplied liquid nitrogen
is vaporized during this process. The gaseous nitrogen is returned
in return tube sleeve 7 and passes through the openings in the
mounting 6 and through the tube 4 to the heating device 10 wherein
it is warmed to room temperature or about 20.degree. C. The gaseous
nitrogen then flows on through the grip member 12 into the space 22
formed between the corrugated pipes 19 and 21 and passes in this
hallow space to the exhauster of the central unit and from there to
the outside.
Upon releasing the trigger 15, the valve in the central unit and
the valve 16 in the grip member are closed and the suction fan is
cut off. The conduit 18 is, however, still filled with liquid
coolant. If the probe is not operated for an additional period of
time and a portion of the liquid gas remaining in line 18
evaporates, the pressure in this line will rise. In order to avoid
any damage to the apparatus thereby, the valve 16 is fashioned as a
safety valve in such a manner that the valve cone is lifted against
the force of a spring by the pressure of the medium present in line
18, and the medium can then exit through the tip 3 of the feed line
1. In case the probe tip is still resting on a counter surface and
the exiting coolant thus cannot freely be released, the gaseous
medium can readily flow off through the return line, even if the
suction fan is not on.
The suction fan in the central unit need not be actuated only upon
opening of the magnetic valve in the control device and of the
valve 16 in the probe; rather, it can if so desired, be run
continuously, On the other hand, it can also be advantageous to
provide means to cut off the blower even when both valves are
opened.
It should furthermore be noted that the probe of the device of the
present invention can also be provided with a conventional
endoscope, if it is necessary to employ the tip of the probe at
places which are not readily accessible optically.
From the foregoing description, one skilled in the art can easily
ascertain the essential characteristics of this invention, and
without departing from the spirit and scope thereof can make
various changes and modifications of the invention to adapt it to
various usages and conditions.
* * * * *