DE102008061063B4 - Cryoprobe, cryosurgical device - Google Patents

Abstract

Cryogenic probe, comprising: - a cooling device (20) having an inlet (21) for supplying a fluid into an expansion region and with a return (15) for the removal of the expanded fluid, - a contact region (23) for fixing and extraction of tissue an opening (37) for receiving at least a portion of the extracted tissue, characterized in that the return (15) for receiving and / or for transporting the tissue in fluid communication with the opening (37 ), wherein a valve (30) for closing the opening (37) is arranged and designed such that the valve (30) opens at a negative pressure in the interior of the cryoprobe.

Description

The invention relates to a cryoprobe and a cryosurgical device according to patent claims 1 and 10, respectively.

Cryobiopsis is a special procedure in the field of endoscopy, to take tissue samples from the body of a patient and thus not only to facilitate the diagnosis of a possible clinical picture, but also to improve.

The removal process usually proceeds as follows: A cryoprobe is placed with light pressure on the tissue to be examined. By strongly cooling the probe head, the tissue in the contact area is frozen to the probe. After a predetermined period of time, the frozen tissue can be extracted by mechanical pulling on the probe.

The rapid and strong cooling of the probe head (to about -50 ° C) is achieved by the Joule-Thomson effect. In doing so, it makes good use of the fact that gas cools down strongly when it is expanded under high pressure through a nozzle into an expansion chamber. The expansion preferably takes place in the probe head and deprives the probe of heat so that the target tissue freezes.

To perform a cryobiopsy different devices are known. A cryosurgical instrument goes out of the US 2003/0195436 A1 out. This instrument is particularly suitable for sifting and "coring" of tumors. It includes a handle that is connected to a probe. The probe has at its distal end a probe head having a lance-shaped configuration. The probe head can be cooled as described. Furthermore, the instrument has a withdrawal cannula. For removal, the tissue is impaled with the lance or the probe head and festgeeist on this. By advancing the withdrawal cannula, a part of the festgeeisten tissue is cut out of the tumor or better punched. By removing the instrument, the excised tissue sample can be removed. To facilitate the cutting process, describes the US 2003/0195436 A1 an accelerator which is driven by a spring and drives the cannula with a predetermined force into the tissue.

The DE 10 2007 020 582 A1 describes a cryoprobe having an inlet for supplying a fluid into an expansion area and a return for removing the expanded fluid. Furthermore, the cryoprobe has the DE 10 2007 020 582 A1 a contact area that is coolable for fixation and extraction of tissue. The removal of tissue samples with the Krysonde the DE 10 2007 020 582 A1 is not optimally solved, since the probe must be removed for the removal of tissue samples from the endoscope usually used for this purpose.

The instruments mentioned are not suitable for taking a large number of tissue samples.

• 1. Das Operationspräparat, welches durch höhere Invasivität (intraoperativ) gewonnen wird und sich durch größere Mengen, bessere Qualität und somit bessere Aussagekraft auszeichnet;
• 2. Das Gewebepunktat/-biopsat, welches durch deutlich weniger invasive Maßnahmen gewonnen wird, aber häufig eine geringe Gewebemenge, schlechte Qualität (Blutung, Quetschung, etc.) und somit schlechte Aussagekraft aufweist;

A tissue sample is generally understood to mean the removal and examination of biological material from a living organism. The removed tissue is examined by the pathologist cytologically (microscope, little material), but better histologically (microscope, much material) with or without staining technique, as well as immunological and molecular-biological auxiliary procedures. In principle, two basic forms of tissue recovery can be distinguished depending on the required amount of material and the accessibility of the target tissue:

• 1. The surgical specimen, which is obtained by higher invasiveness (intraoperatively) and is characterized by larger quantities, better quality and thus better informative value;
• 2. The tissue epitope / biopsy, which is obtained by significantly less invasive measures, but often a small amount of tissue, poor quality (bleeding, contusion, etc.) and thus has poor predictive power;

If a tissue sample is obtained intraoperatively, the result of the examination can be communicated to the surgeon by phone within a few minutes via the rapid-cut diagnosis, so that the examination result can decisively influence the further course of the operation therapeutically. The central question often arises as to whether it is a benign or malignant tumor.

In addition to the biopsy probe mentioned above, there are also mechanical forceps that are used in flexible endoscopy. The forceps are brought through the working channel of a flexible endoscope to the target tissue, which is captured by these and removed by a mechanical train. In this case, different shapes of the jaw parts and different sizes of pliers are used. The recovery of the specimen is done by removing the biopsy forceps from the flexible endoscope. The collected samples are placed in sample containers and sent to the pathologist for histology. For a better diagnostic value usually a plurality of samples, for example three to five is taken. In indicated cases, it may be necessary to withdraw more than thirty samples from the suspected target tissue. The time required, which is necessary for the removal of the samples, proves to be not insignificant and means for the patient a heavy burden.

The size of the biopsy depends essentially on the size of the chosen forceps. Due to the mechanical grasping it comes to a contusion of the tissue, whereby the later fine-tissue investigation is made more difficult. Cells in the marginal area of the biopsy specimen are usually defective; tumor demarcation can only be diagnosed conditionally. It also comes in proportion to the size of the forceps to bruises and bleeding, which represent disturbing artifacts. In some cases, it may be necessary to perform the biopsy again.

Generally, the removable biopsy size is limited by the diameter of the working channel of the endoscope. A biopsy in the gastrointestinal tract uses very long endoscopes. Colonoscopy with a flexible endoscope can take up to 15 minutes to pretend the device alone until the point of reversal. The endoscopes used here have working channels with a diameter between 4.5 and 1.3 mm. Therefore, only very small device can be used. Due to the long duration of the insertion and removal process (probe lengths of up to 3 m) often only one sample can be taken.

The US 2006/0184063 A1 shows an instrument for taking a variety of samples. The instrument of US 2006/0184063 A1 however, cuts the tissue out with a knife, resulting in detrimental results.

Based on the above-mentioned prior art, it is an object of the present invention to provide an improved cryoprobe, in particular for colonoscopy. In particular, a cryoprobe should be provided, which enables effective and rapid removal of a large number of tissue samples. The cryoprobe should be usable under very difficult working conditions (low working channel diameter, very long probes, angled endoscope). Furthermore, a corresponding cryosurgical device is to be provided.

This object is achieved by a cryoprobe according to claim 1.

An essential idea of the present invention is therefore to use the return both in connection with the cooling device as well as for receiving and / or transporting off tissue. According to the invention, what is understood as the return is all that is used to remove the expanded fluid from the expansion area. Probes with flexible and rigid returns are known. In a rigid return, a pressure-resistant line is provided, which removes the fluid. In non-return cryoprobes, the probe shaft or other cavity serves to carry away the fluid.

Extraction involves detaching a target tissue or tissue from a living organism. Preferably, this extraction is accomplished by freezing the contact area on the target tissue and mechanically pulling so that a portion of the tissue is torn out.

Due to the special reflux, which fulfills a dual function according to the invention, it is possible to produce very thin and long cryoprobes, which enable both detachment of the tissue and removal of the detached tissue.

The opening can open into the return. It is conceivable to use the fluid connection between the return and the opening only to take extracted tissue into the opening or to position it there. Preferably, however, the return connects to the opening and allows removal of the extracted tissue by the return.

The cryoprobe includes a valve for closing the opening. It is conceivable to operate the Krysonde open. However, in order to avoid leakage of the fluid used for cooling in the body to be treated, a valve is provided which avoids the escape of the gas during operation of the cooling device. Thus, the risk of over-dilation of hollow organs or emphysema in the adjacent tissue is reduced.

The valve is arranged and configured such that the valve opens at a negative pressure in the interior of the cryoprobe. It is possible to "manually" open the valve by providing a corresponding mechanism or corresponding electrical components. An automatic opening of the valve occurs when creating a negative pressure inside the cryoprobe, in particular in the return. Thus, the valve opens automatically when sucking the tissue sample through the return line.

The contact region may comprise a cooling plate which is formed from a material with good thermal conductivity, in particular with a specific thermal conductivity> 0.5 λ ₀ , in particular greater than 1 λ ₀ . It is advantageous if the cold produced by the cooling device is distributed over a large area, so that as large a tissue sample as possible freezes on the cryoprobe. The adhesive force is thus increased and the removal of large samples allows. Preferably, the cooling plate is configured and arranged such that a cooling from the inside to the outside (centrifugally) takes place. With good thermal conductivity, it is possible within a few seconds to obtain the largest possible, almost circular tissue sample.

The cryoprobe may include a nozzle for cooling the contact area by means of the Joule-Thomson effect. It is conceivable to use a refrigerant to achieve the cooling of the contact area. However, preference is given in the cryobiopsy to cooling by means of the Joule-Thomson effect.

It is also conceivable to facilitate the suction process by a lubricant or lubricant. Preferably, however, the removed tissue is accomplished by means of negative pressure alone.

The return may be designed to transport the tissue in the proximal direction. Preferably, the return and the opening are coordinated such that the biopsy is taken in the presence of a corresponding negative pressure through the opening and transported away via the return. For example, with a substantially circular configuration of the opening and the return, the diameter of the opening may be less than or equal to the diameter of the return.

The fluid inlet can comprise a line, in particular a pressure-resistant line, which is arranged laterally on a probe shaft. Due to the lateral guidance of the line, in particular acentric, the available interior of the shaft of the probe can be optimally utilized. Tissue samples can be transported in the return approximately as large as the diameter of the probe shaft.

The cryoprobe may comprise a collecting device for receiving the tissue, in particular at the proximal end of the cryoprobe. Is to apply the negative pressure z. For example, if a conventional surgical nipple is used, the retrieval device may separate exhaust air and sampled tissue sample or a plurality of tissue samples taken so that the tissue samples may be used for diagnosis.

For this purpose, the collecting device can comprise at least one filter device permeable to a fluid.

The collecting device can be arranged detachably on the cryoprobe. This allows a simple and fast processing or a simple and fast onward transport of the samples obtained. Furthermore, sterility requirements can be met.

The above object is also achieved by a cryosurgical device according to claim 10.

The cryosurgical device may include a controller that operates the cryoprobe in an extraction mode such that tissue destined for extraction freezes at the contact region, and in a suction mode operates the cryoprobe so that the extracted tissue is aspirated into the interior of the cryoprobe via the opening , For this purpose, the controller can actuate, for example, corresponding actuators (eg valves, relays, etc.).

The controller may be configured such that in the suction mode, the cooling device is deactivated. Thus, in a first step, the tissue is frozen to the contact area, in a second step, the mechanical extraction of the frozen tissue from the corresponding organ takes place. In a third step, the cryoprobe thaws while the dissolving tissue sample is sucked into the interior of the cryoprobe.

The invention will be described with reference to some embodiments, which are explained in more detail by means of illustrations. Hereby show:

1 a schematic representation of the distal end of a cryoprobe according to the prior art;

2 the distal end of a cryoprobe according to the invention (semi-open system);

3 the distal end of a cryoprobe according to the invention with valve;

4 the distal end of another embodiment of the cryoprobe according to the invention;

5 and 6 a plan view of the distal ends of cryoprobes according to the invention;

7 a schematic representation of a cryoprobe with connections for the cooling device and the recovery device;

8th a schematic representation of a cryoprobe with an APC function;

9 to 15 a removal process according to the invention of a biopsy sample with a cryoprobe;

16 the removal procedure of a biopsy specimen with an APC probe;

17 a collecting device according to the invention for a biopsy material;

17a a cover for the catcher 17 ;

17b the catcher off 17 when taking a sample;

18 and 19 Cryo probes with collecting devices.

In the following description, the same reference numerals are used for the same and like parts.

7 shows a first embodiment of a cryoprobe according to the invention 10 , This includes a handle 18 and a distally extending elongated probe shaft 12 , The head of the cryoprobe 10 forms the final piece 11 , To operate a cooling device 20 and the receiving device comprises the cryoprobe 10 a gas connection 29 or a suction connection 34 ,

According to the prior art are closed cooling devices 20 known. The 1 shows the distal end of a corresponding cryoprobe 10 , A fluid, in particular a gas, is under high pressure via a gas line 21 to the distal end of the cryoprobe 10 transported. There, the gas escapes through a nozzle 24 in the interior 15 of the probe shaft 12 , The interior 15 thus acts as an expansion area. Due to the Joule-Thomson effect, heat is removed from the system in the expansion area. It comes to a cooling of the cryoprobe 10 , in particular the final piece 11 , A particularly strong cooling occurs on a cooling plate 23 on, which is substantially perpendicular to the longitudinal direction of the cryoprobe 10 extends and forms the distal end. This cooling plate 23 serves for fixation of the tissue to be extracted and for its mechanical extraction. That in the interior 15 escaping gas is transported away via the interior, which simultaneously forms the return line. For this purpose, one to the cryoprobe 10 connected operating theater vacuum cleaner. A transition piece 13 serves as an adapter between the end piece 11 and probe shaft 12 ,

2 shows an embodiment of the cryoprobe according to the invention 10 , It is a semi-open system, whereby as in 1 Gas under high pressure to the distal end of the cryoprobe 10 over the gas line 21 is transported. The cryoprobe 10 includes an opening 37 , which, as explained in more detail below, serves to accommodate tissue samples. This opening 37 extends along the longitudinal axis of the cryoprobe 10 and forms a continuation of the interior 15 , The gas from the gas line 21 enters this interior 15 near the edge area of the end piece 11 out. There is a cooling of the system due to the expansion of the gas. To the cryoprobe 10 a surgical suction device is connected, so that the expanded gas is discharged in the proximal direction. Although a fluid connection between the opening 37 and the gas line 21 over the interior 15 exists, only little gas from the cryoprobe occurs 10 out.

The cooling plate 23 extends annularly around the opening 37 , At one point she is the nozzle 24 the gas line 21 immediately adjacent. The cooling plate 23 is made of thermally conductive material. When operating the cooling device 20 the cold spreads over the cooling plate 23 , Tissue that with the cooled cooling plate 23 is in contact, is frozen directly to this. Once a tissue sample has been removed from an organ, it can be transferred via the return or the interior 15 be transported away.

9 to 15 shows this process in individual execution steps.

In a first step (compare 9 ) becomes the cryoprobe according to the invention 10 including the end piece 11 and the probe shaft 12 , introduced to a target tissue. In the process shown is a sample 5 from the wall of the gastrointestinal tract, which is essentially mucosa 1 , Submucosa 2 and muscularis 3 includes, be removed.

In a second step ( 10 ) sets the distal end of the cryoprobe 10 on the target tissue, namely the mucosa 1 , on.

In a third step (compare 11 ), the target tissue is sucked through a negative pressure in the return so that this is the opening 37 closes. The target tissue is now on the end piece 11 , in particular on the annular cooling plate 23 at.

In a fourth step, the cooling device 20 activated to the cooling plate 23 to a temperature of about -50 ° C to cool. The target tissue is at the cooling plate 23 firmly. An operating suction device for applying the negative pressure can be active in order to suck the expanding gas.

In a fifth step, the tissue sample 5 torn out of the wall of the gastrointestinal tract by a short pull. The surgical Sucker remains activated and prevents together with the cooling device 20 a loss of the sample 5 ,

In a sixth step ( 14 ) is the cooling device 20 disabled. The tissue sample 5 slowly thaws, the bond between the contact plate 23 and the tissue sample 5 dissolves. Due to the further negative pressure, the tissue sample 5 in the interior 15 , so the return, the cryoprobe 10 sucked.

In a seventh step (compare 15 ) is the recovered tissue sample 5 in the proximal direction of the cryoprobe 10 removed. It is possible the tissue sample 5 in this way in a catcher 50 (compare for example 18 or 19 ).

With the described method, it is possible to take a variety of samples within a short time. Introducing the cryoprobe 10 into the working channel of an endoscope is only necessary at the first removal procedure. After that, a variety of tissue samples 5 at a substantially unchanged position of the cryoprobe 10 be taken within the working channel.

The 3 and 4 show further embodiments of the cryoprobe according to the invention 10 ,

The 3 shows a cryoprobe 10 with a valve 30 , The cooling plate 23 is annular. There is a cooling of the cooling plate 23 through the cooling device 20 , The opening 37 is through a valve 30 locked. Thus, the cryoprobe provides 10 of the 3 during operation of the cooling device 20 a closed system in which the gas used for cooling in the distal region of the cryoprobe 10 can not escape. During operation of the cooling device 20 is the to the cryoprobe 10 connected Suction cups disabled or it is operated at a very low power. In the interior 15 prevail essentially atmospheric pressure conditions. In particular, the pressure in the interior corresponds 15 essentially the pressure of the outside of the cryoprobe 10 can be found. A valve flap 31 of the valve 30 is biased so that the opening 37 remains closed at this pressure ratio. After switching off the cooling device 20 the connected suction pad is activated. It creates a negative pressure in the interior 15 , This negative pressure is sufficient to the bias of the valve flap 31 to overcome. One on the cooling plate 23 Frozen tissue sample 5 becomes with the opening of the valve 30 in the interior 15 sucked in and transported away in the proximal direction.

In a further embodiment ( 4 ) of the cryoprobe according to the invention 10 surpasses the final piece 11 with the cooling plate 23 the opening 37 ,

In the plan view (cf. 5 and 6 ) can the cooling plate 23 for receiving the tissue sample 5 be formed circular. The opening 37 may also be circular or formed as a semicircle. Preferably, this embodiment is also provided with a valve 30 provided so that the opening 37 by means of a flap 31 is closable.

The ablation probe or cryoprobe according to the invention 10 can also be used to advantage as an APC instrument for combined use with argon plasma coagulation. The 8th and 16 show a correspondingly adapted device, with additional connections, namely an argon connection 40 and an RF connection 42 are provided. The final piece 11 can, as in 16 shown to be designed such that it serves as an APC electrode. Through the opening 37 emits argon, which is ionized by a sufficiently high RF voltage. The RF current applied to the APC electrode causes a thermal effect on the target tissue. The argon plasma coagulation can be advantageously used for hemostasis during or after tissue sampling. For the APC application, it is beneficial if the cooling plate 23 is performed electrically insulating and comprises a material that has a good thermal conductivity.

It is conceivable, the cryoprobe 10 to necrotize polyps and to remove them.

Furthermore, it is conceivable to use the cryoprobe according to the invention 10 to be used in recanalization in a hollow organ.

One aspect of the present invention is a catcher 50 to provide such that the tissue samples 5 can be further processed. The 18 and 19 show corresponding cryoprobes with handles 18 , the removable collecting devices 50 include. The catcher 50 is over two plug connections with the handle 18 connected and coupled into the return, that the extracted gas or gas mixture or fluid via an input port 59 (see 17 ) in the catcher 50 enters and via an output terminal 59 ' from the chambers 56 . 57 the catcher 50 escapes. So is a tissue sample 5 over the return or interior 15 in the proximal direction of the cryoprobe 10 transported away, so this enters the catcher 50 and is there on a partition wall 55 , which has the function of a filter, withheld. The gas used to transport the tissue sample 5 is present, the dividing wall can be 55 penetrate and is via the suction connection 34 , which is connected to the surgical suction device, dissipated.

It is possible the cryoprobe 10 according to 18 without the catcher 50 to operate. In this case, the closure device forms 70 instead of the catcher 50 can be used, a portion of the return. A filtering of the tissue sample 5 not done.

Preferably, the catcher is 50 from a soil 51 with a partition 55 built up. The partition 55 extends centrally through the catcher 50 and divides these into a first chamber 56 and a second chamber 57 , The side is the catcher 50 through the side wall 53 limited. A lid 58 closes the chambers 56 . 57 at the upper end and includes the input port 59 and the output terminal 59 ' , To the tissue samples 5 to transport includes the catcher 50 a transport cap 60 ( 17a ), in the uncoupled state of the catcher 50 the input terminal 59 and the output terminal 59 ' closes.

In an embodiment of the collecting device 50 are the side walls 53 removable (compare 17b ) allowing to take out the tissue samples 5 is relieved.

In a further embodiment of the cryoprobe 10 with catcher 50 (see 19 ) This has a plug-in coupling for the RF connection 42 and a plug connection for a suction connection hose 36 on. By the possibility of the connections from the handle 18 To separate, the handling of the instrument is improved.

LIST OF REFERENCE NUMBERS

1

mucosa

2

submucosa

3

muscularis

5

Tissue sample (s)

10

cryoprobe

11

terminating piece

12

probe shaft

13

Transition piece

15

inner space

18

handle

20

cooling device

21

gas pipe

23

cooling plate

24

jet

29

gas connection

30

Valve

31

valve flap

34

suction

36

Absauganschlussschlauch

37

opening

40

argon connection

42

RF connector

50

catcher

51

ground

53

Side wall

55

partition wall

56

first chamber

57

second chamber

58

cover

59

input port

59 '

output port

60

transport cap

70

closure device

Claims (12)

A cryoprobe comprising: - a cooling device ( 20 ) with a feed ( 21 ) for supplying a fluid in an expansion area and with a return ( 15 ) for removing the expanded fluid, - a contact area ( 23 ) used for fixation and extraction of tissue by the cooling device ( 20 ) is cool, - an opening ( 37 ) for receiving at least a portion of the extracted tissue, characterized in that the return ( 15 ) for receiving and / or removing the tissue in fluid communication with the opening ( 37 ), whereby a valve ( 30 ) for closing the opening ( 37 ) is arranged and designed such that the valve ( 30 ) opens at a negative pressure inside the cryoprobe. Cryogenic probe according to claim 1, characterized in that the opening ( 37 ) in the return ( 15 ) opens. Cryoprobe according to one of the preceding claims, characterized in that the contact area ( 23 ) comprises a cooling plate formed of a material having good thermal conductivity. Cryogenic probe according to one of the preceding claims, characterized by a nozzle ( 24 ) for cooling the contact area ( 23 ) by means of the Joule-Thomson effect. Cryogenic probe according to one of the preceding claims, characterized in that the return ( 15 ) is designed to transport the tissue in the proximal direction of the cryoprobe. Cryo probe according to one of the preceding claims, characterized in that the inlet ( 21 ) comprises a pressure-resistant line, which laterally on a probe shaft ( 12 ) is arranged. Cryogenic probe according to one of the preceding claims, characterized by a collecting device ( 50 ) for receiving the tissue at the proximal end of the cryoprobe. Cryogenic probe according to claim 7, characterized in that the collecting device ( 50 ) at least one fluid-permeable filter device ( 55 ). Cryogenic probe according to claim 7 or 8, characterized in that the collecting device ( 50 ) is detachably attached to the cryoprobe. A cryosurgical device comprising: - A cryoprobe according to one of the preceding claims; - A suction device, which is for receiving the tissue in the cryoprobe and / or for transporting the tissue with the return in operative connection. Cryosurgical apparatus according to claim 10, characterized by a controller which operates in an extraction mode, the cryoprobe such that for extraction tissue at the contact area ( 23 ) and, in a suction mode, operates the cryoprobe so that extracted tissue passes over the opening (FIG. 37 ) is sucked into the interior of the cryoprobe. Cryosurgical device according to claim 11, characterized in that in the suction mode the cooling device ( 20 ) is disabled.

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