JP5207242B2 - Cryo medical instruments - Google Patents

Description

  The present invention relates to a cryomedical device for performing cryogenic treatment.

In recent years, cryotherapy for treating an affected area of a patient using an ultra-low temperature fluid such as argon gas has been performed.
For example, when treating lung cancer with this cryotherapy, the probe of the medical instrument is punctured into the patient's body so that the tip reaches the lung cancer tissue, and in this state, cryogenic gas such as argon gas is first supplied to the probe. The lung cancer tissue is then frozen, and then the lung cancer tissue is necrotized by supplying a thawing gas such as helium gas to the probe and thawing the frozen lung cancer tissue. It is described in Non-Patent Document 1.

Non-Patent Document 2 and the like describe cryotherapy in which treatment is performed using a medical instrument.
The cryotherapy described in Non-Patent Document 2 is a double tube (coaxial needle) with a sharp tip, as described in “Ringing method and practice of cryotherapy” from the right column of page 10 to page 11. ) Is placed on the patient's body surface, a long and thin guide needle is inserted along the central axis of the double tube, and the guide needle is punctured to the affected area.
Thereafter, the double tube is advanced along the guide needle to the affected part and further penetrated into the tumor. Then, the guide needle is removed, and a freezing terminal (probe) is inserted and loaded along the hollow shaft in the double tube instead.
In this method, high-pressure argon gas as a freezing gas and high-pressure helium gas as a thawing gas are alternately supplied to a freezing terminal, and the affected part is necrotized by repeating freezing and thawing in a short time.
The magazine “Ayumi of Medicine” (Vol. 206 No. 3, 2003. 7.19). Kawamura et al., “Freeze-thaw necrosis therapy for lung cancer” (P229-P231). Magazine "Cryogenic Medicine" (30, 2004). Nakatsuka, Kawamura et al., “Percutaneous cryotherapy for lung malignant tumor using CT fluoroscopy” (P9-P15).

The medical instrument used for the cryotherapy described in Patent Documents 1 and 2 has a structure in which a frozen gas and a thawed gas are alternately sent into a probe made of a metal tube such as stainless steel so that the affected part is necrotized. The probe is inserted into a mantle tube (double tube) punctured into the affected area, and frozen gas and thawing gas are alternately supplied into the probe from a gas supply tube connected to the probe.
For this reason, the high-pressure gas rarely jets into the mantle tube because the connector for connecting the probe and the gas supply tube is disconnected during the cryotherapy.
When high pressure gas is ejected into the outer tube, the probe is inserted into the distal end of the outer tube, and the probe is ejected from the distal end of the outer tube to the affected area due to the pressure of the high pressure gas. There is a problem in safety because it may be ejected from the guide hole at the tip of the mantle tube into the patient's body.
The present invention has been made to remedy such a problem, and in the event of a gas leak in the outer tube, the freezing that prevents the probe from jumping out of the distal end of the outer tube or jetting high-pressure gas into the patient's body. The object is to provide a medical device.

  The cryomedical device of the present invention is used for cryotherapy in which the affected part is necrotized by repeatedly supplying the frozen gas and the thawing gas to the probe inserted into the outer tube punctured in the affected part, and repeating the freezing and thawing of the affected part. The cryomedical device is provided with a retaining means at the distal end portion of the outer tube that prevents the probe from jumping out from the distal end of the outer tube due to high-pressure gas due to gas leakage generated in the outer tube.

With this configuration, if a gas leak occurs in the outer tube for some reason during cryotherapy, the probe jumps out from the guide hole opened at the distal end of the outer tube to the affected area at a high speed due to the high-pressure gas leaking into the outer tube. Since the retaining means provided at the distal end of the mantle tube prevents this from happening, the safety of the cryotherapy is improved.
Also, by making the outer tube sufficiently heavy with respect to the probe, the outer tube can sufficiently absorb the kinetic energy applied to the probe in the protruding direction, so that the probe can be reliably prevented from protruding. .

  The cryomedical device of the present invention is used for cryotherapy in which the affected part is necrotized by repeatedly supplying the frozen gas and the thawing gas to the probe inserted into the outer tube punctured in the affected part, and repeating the freezing and thawing of the affected part. A cryomedical device, an outer tube having a guide hole for inserting a guide needle for guiding the probe to the affected area, and a detachable housing in the outer tube, and a proximal end portion of the outer tube through a connector. A probe connected to the gas supply source, a retaining means provided at the distal end of the outer tube to prevent the probe from jumping out of the distal end of the outer tube due to high pressure gas due to gas leakage generated in the outer tube, and a connector By electrically detecting the detachment, gas leakage detection means for detecting gas leakage in the outer tube, and gas supply to the probe is stopped by the gas leakage signal detected by the gas leakage detection means. It is obtained by construction and control means for.

With this configuration, if a gas leak occurs in the outer tube for some reason during cryotherapy, the probe jumps out from the guide hole opened at the distal end of the outer tube to the affected area at a high speed due to the high-pressure gas leaking into the outer tube. Since the retaining means provided at the distal end of the mantle tube prevents this from happening, the safety of cryotherapy is improved and the mantle tube is sufficiently heavy with respect to the probe so that it can be added to the probe. Since the outer tube can sufficiently absorb the kinetic energy in the protruding direction, it is possible to reliably prevent the probe from protruding.
Further, when the gas leak detection means 14 detects, the control means can instantaneously stop the gas supply and prevent the high pressure gas leaking into the outer tube from being ejected from the proximal end side opening of the outer tube. In addition to preventing the probe from popping out, double safety can be achieved.

  In the cryomedical device of the present invention, the retaining means is a sealing member in which the small-diameter portion having an inner diameter smaller than the outer diameter of the probe and the probe's distal end is in close contact with the outer peripheral surface of the outer tube. It consists of a stop surface.

  With the above configuration, the tip of the probe is pressed against the sealing surface by the high-pressure gas leaking into the outer tube, and the sealing surface and the tip of the probe are brought into close contact with each other. Therefore, the high pressure leaked into the outer tube due to the sealing action by the probe It is possible to prevent the gas from being ejected from the induction hole into the patient's body.

  According to the cryomedical device of the present invention, when a gas leak occurs in the outer tube for some reason during the cryotherapy, the probe is opened from the guide hole opened at the distal end portion of the outer tube by the high pressure gas leaked into the outer tube. The retaining means provided at the distal end of the mantle tube prevents high-speed gas from leaking into the mantle tube, and the retaining means provided at the tip of the mantle tube prevents high speed gas from leaking into the mantle tube. Since the sealing surface and the outer peripheral surface on the tip side of the probe are brought into close contact with each other, the high-pressure gas leaking into the outer tube due to the sealing action by the probe is prevented from being ejected from the guide hole into the patient's body. Can be prevented.

Embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an overall configuration diagram of a cryomedical device, FIG. 2 is a cross-sectional view of a state where a probe is inserted into a mantle tube, and FIG. 3 is an enlarged view in a circle A of FIG.
A cryomedical device shown in FIG. 1 includes a probe 1, an outer tube 2 into which the probe 1 is inserted, a gas supply unit 10 that supplies high-pressure gas to the probe 1, and a gas supply tube that connects the probe 1 and the gas supply unit 10. 7 and a guide needle (not shown) for guiding the probe 1 to the affected area.
The probe 1 is formed of a stainless steel tube having an outer diameter of, for example, 3 mm or less, and has a high-pressure gas forward path 1a and a return path 1b formed therein, and has a sharp conical or spindle-shaped tip side. The distal end portion is exposed to the affected area through a guide hole 2 b opened at the distal end portion 2 a of the outer tube 2.

The forward path 1 a in the probe 1 is formed by a thin metal tube 1 c that passes through the central axis of the probe 1, and one end side of the metal tube 1 c is connected to a heat exchanger 4 provided inside the distal end side of the probe 1. ing.
A tip nozzle 1d is formed at the tip of the forward path 1a projecting from the heat exchanger 4 into the tip of the probe 1, and the tip of the probe 1 is cooled to a cryogenic temperature by the frozen gas ejected from the tip nozzle 1d. In addition, it is heated by a thawing gas.

The high-pressure gas ejected from the tip nozzle 1d in the forward path 1a flows from the return path 1b formed in the probe 1 to the proximal end side of the probe 1 through the heat exchanger 4, and the heat exchanger 4 When passing through, heat is exchanged with the high-pressure gas flowing through the forward path 1a, thereby effectively using energy.
A connector 5 for connecting a gas supply pipe 7 is provided on the proximal end side of the probe 1.
The connector 5 is formed in a short cylinder shape from an electrically insulating material having an extremely low temperature resistance, and has an outer diameter slightly smaller than the inner diameter of the outer tube 2.
At the center of the connector 5, an intake port 5a in which one end of a metal pipe 1c forming the forward path 1a is fitted in an airtight manner is opened, and the high pressure that has circulated through the return path 1b is formed around the metal pipe 1c. One or a plurality of exhaust ports 5b for discharging the gas to the outside of the probe 1 are opened.

The outer tube 2 for inserting the probe 1 is formed of, for example, a stainless steel tube similar to the probe 1, and the inner diameter is slightly larger than the outer diameter of the probe 1. In order to obtain it, it is thicker than the thickness of the probe 1 and is formed, for example, to be 100 times the weight of the probe 1.
The distal end portion 2a of the outer tube 2 is formed so that the distal end side is gradually thinned as shown in FIG. 2 so that the work when the guide hole is guided to the subject by guiding the guide hole 2b to the subject is facilitated. The distal end portion 2a has a sharp conical shape, and a retaining means 3 is formed on the inner peripheral surface of the distal end side of the outer tube 2.

The retaining means 3 is a high pressure jetted from the gas supply pipe 7 into the outer tube 2 when a connector 5 provided on the probe 1 side and a connector 6 described later provided on the gas supply pipe 7 are separated for some reason. The probe 1 prevents the probe 1 from jumping out from the inside of the guide hole 2b opened at the distal end portion of the outer tube 2. As shown in FIG. 3, the small diameter portion 3a bulges on the inner peripheral surface of the outer tube 2 as shown in FIG. Are formed in a ridge shape in the circumferential direction.
The inner diameter of the small diameter portion 3a is smaller than the outer diameter of the probe 1, and the proximal end portion side of the outer tube 2 is loosely arcuate so that the distal end side corner portion of the probe 1 is in close contact with the minimum diameter portion of the small diameter portion 3a. The sealing portion 3b is formed of an inclined surface, and the distal end side of the outer tube 2 from the minimum diameter portion of the small diameter portion 3a is an inclined surface 3c connected to the sharp distal end portion 3a.

On the other hand, the proximal end side of the outer tube 2 is formed longer than the probe 1 so that the probe 1 can be inserted into the outer tube 2 from the proximal end side opening of the outer tube 2, and the probe 1 is repeatedly used. On the other hand, the outer tube 2 has a disposable specification that is discarded once used like the injection needle.
A connector 6 for connecting a gas supply means 10 to the probe 1 via a gas supply pipe 7 is detachably fitted to the connector 5 of the probe 1.
The connector 6 is made of a material having the same cryogenic temperature resistance and electrical insulation as the connector 5 and is formed in a cylindrical shape slightly larger in diameter than the connector 5, and is fitted into a fitting recess 5 c formed on the end surface of the connector 5. A fitting projection 6 a that can be freely fitted is formed, so that the fitting projection 6 a can be fitted into the proximal end side opening of the outer tube 2.

The fitting recess 5c of the connector 5 and the fitting projection 6a of the connector 6 are formed with positioning means (not shown) such as a two-sided width for positioning the fitting position. The air supply port 6b and the exhaust port 6c provided on the 6 side can be connected to the air supply port 5a and the exhaust port 5b on the connector 5 side in an airtight manner.
An air supply port 6b formed in the connector 6 is connected to a switching valve 8 of the gas supply means 10 via a gas supply tube 7 made of a flexible tube such as a tube, and a flexible port is provided to the exhaust port 6c. A gas discharge pipe 9 made of a pipe is connected.

As shown in FIG. 1, the gas supply means 10 includes a freezing gas supply source 10a for supplying a freezing gas made of high-pressure argon gas, and a thawing gas supply source 10b for supplying a thawing gas made of high-pressure helium gas. The freezing gas supply source 10a and the thawing gas supply source 10b are connected to the switching valve 8 via on-off valves 12 and 13 made of electromagnetic valves or the like.
The switching valve 8 can be switched at a constant cycle by a control means (not shown), so that the frozen gas and the thawing gas can be alternately supplied to the probe 1 through the gas supply pipe 7. .

On the other hand, between the connectors 5 and 6 that connect the probe 1 housed in the outer tube 2 and the gas supply pipe 7, a contact 14a of the gas leak detecting means 14 for detecting gas leak is provided.
The contact points 14a of the gas leak detection means 14 are respectively provided in the connectors 5 and 6 that are fitted to each other. When the connector 5 and the connector 6 are fitted to each other, the respective contacts 14a are electrically short-circuited. It is like that.

The contact 14a on the connector 6 side is connected to the secondary coil 17a of the transformer 17 by a signal line 15 consisting of two parallel wires, and the midpoint 17b of the secondary coil 17a is grounded.
And the gas leak detection means 14 is connected between the secondary coils 17a of the transformer 17, and it detects gas leak by the voltage change between the secondary coils 17a, and the gas leak detection means 14 detected. The gas leak signal is sent to the control means, and the control means instantaneously closes the on-off valves 12 and 13 by the gas leak signal sent from the gas leak detection means 14, and the frozen gas or thawing sent to the probe 1. The gas is cut off.

Next, the operation of the cryomedical device constructed as described above will be described. When a cryomedical device is used to treat an affected area such as lung cancer, the mantle tube is first inserted in the mantle tube 2 with the distal end side of the guide needle inserted. The tip of 2 is brought into contact with the body surface of the patient, and in this state, the guide needle is punctured into the patient's body so that the tip reaches the affected tissue.
Next, the mantle tube 2 is punctured into the patient's body using the guide needle as a guide. The tip 2a of the mantle tube 2 has a sharp conical shape as shown in FIG. Can be done easily and in a short time.

When the distal end of the outer tube 2 penetrates the affected tissue, the guide needle is withdrawn from the outer tube 2, and the probe 1 is inserted into the outer tube 2 in this state as shown in FIG. Inject a small amount of distilled water or physiological saline in advance.
As a result, the air in the outer tube 2 is discharged to the outside of the outer tube 2, and at the same time, a water film is formed between the inner peripheral surface of the outer tube 2 and the outer peripheral surface of the probe 1 to reduce friction between them. Therefore, the probe 1 can be easily inserted into the outer tube 2.
When the tip of the probe 1 inserted into the outer tube 2 reaches the small diameter portion 3a of the retaining means 3 provided on the inner peripheral surface of the outer tube 2 as shown in FIG. Since it does not advance, the insertion of the probe 1 is stopped in this state.
When the insertion of the probe 1 is completed, the connector 6 is opened to the proximal end side of the outer tube 2 in a state where the connector 5 provided on the proximal end side of the probe 1 and the connector 6 provided on the gas supply pipe 7 side are coupled. The preparation for the cryotherapy is completed.

Next, when the cryotherapy is started, after the opening and closing valves 12 and 13 are opened by the control means, the switching valve 8 is first switched to the freezing gas supply source 10a side by the control means, so that the freezing gas is supplied from the freezing gas supply source 10a side. Is supplied to the probe 1 through the gas supply pipe 7.
The frozen gas supplied to the probe 1 reaches the tip nozzle 1d via the heat exchanger 4 from the forward path 1a in the probe 1, and is ejected from the tip nozzle 1d to the tip of the probe 1. The distal end of the outer tube 2 is cooled to a very low temperature, thereby freezing the affected part.

Thereafter, when the switching valve 8 is switched to the thawing gas supply source 10 b side by the control means, the thawing gas is supplied from the thawing gas supply source 10 b to the probe 1 through the gas supply pipe 7.
The thawing gas supplied to the probe 1 reaches the tip nozzle 1d through the heat exchanger 4 by the forward path 1a in the probe 1, and is ejected from the tip nozzle 1d to the tip of the probe 1. The distal end portion of the outer tube 2 is heated, and the freezing of the affected part is thawed.
Thereafter, by switching the switching valve 8 at a constant period by the control means, the frozen gas and the thawed gas are alternately supplied to the probe 1, so that the lung cancer tissue in the affected area is necrotized by the Joule-Thompson effect and is frozen by repeating this. The therapeutic effect by therapy can be obtained.

On the other hand, gas leakage may occur in the outer tube 2 due to the disconnection of the connectors 5 and 6 connecting the probe 1 and the gas supply tube 7 during the cryotherapy.
Although the connectors 5 and 6 that connect the probe 1 and the gas supply pipe 7 have a structure that is not easily detached from the original, the connectors 5 and 6 are not sufficiently coupled, or the connector 5 is not used for a long time. In some cases, the connectors 5 and 6 may be detached from each other when the connecting portion of the.
When a gas leak occurs in the outer tube 2 during the cryotherapy, the high pressure gas leaking into the outer tube 2 instantaneously presses the rear part of the probe 1 inserted into the outer tube 2, so that the probe 1 is used by the high pressure gas. Tries to jump out from the guide hole 2b opened at the distal end 2a of the outer tube 2 to the affected area at high speed.

However, the inner periphery of the distal end portion 2 a of the outer tube 2 is formed with a retaining means 3 composed of a small diameter portion 3 a whose inner diameter is smaller than the outer diameter of the probe 1, and prevents the probe 1 from jumping out of the outer tube 2. At the same time, the outer tube 2 is formed with a weight 100 times that of the probe 1 and can sufficiently absorb the kinetic energy applied to the probe 1 in the protruding direction. Can be prevented.
Further, the tip of the probe 1 is pressure-bonded to the sealing surface 3b formed toward the rear end side from the minimum diameter portion of the small diameter portion 3a by the high pressure gas leaking into the outer tube 2, and the sealing surface 3b and the probe 1 are pressed. Therefore, the high-pressure gas leaked into the outer tube 2 by the sealing action of the probe 1 can be prevented from being ejected from the guide hole 2b into the patient's body.

On the other hand, when the connector 5.6 is detached during the cryotherapy, the contact 14a of the gas leak detection means 14 that has been closed by a short circuit is opened, so the secondary coil 17a of the transformer 17 of the gas leak detection means 14 is opened. A change occurs in the voltage between.
Since the gas leak detection means 14 detects this voltage change and sends a gas leak signal to the control means, the control means instantaneously shuts off the on-off valves 12 and 13 and stops the supply of the frozen gas and the thawing gas.
As a result, gas leakage in the outer tube 2 can be stopped instantaneously, so that the high-pressure gas leaked into the outer tube 2 is prevented from being pushed out and ejected to the rear of the outer tube 2. be able to.

That is, when a gas leak occurs in the outer tube 2 during cryotherapy, the probe 1 is prevented from jumping out of the outer tube 2 to the affected area by the retaining means 3 provided at the distal end portion 2a of the outer tube 2. Since the supply of the freezing gas and the thawing gas is stopped, the safety can be doubled.
In the above-described embodiment, an example in which the present invention is applied to cryotherapy in the case of treating an affected area such as lung cancer has been described, but the present invention can be applied to all cryomedical devices used for diseases for which cryotherapy is effective.

1 is an overall configuration diagram of a cryomedical device according to an embodiment of the present invention. It is sectional drawing of the state which inserted the probe of the cryomedical device which becomes embodiment of this invention in the mantle tube. FIG. 3 is an enlarged view of a circle A in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Probe 2 Outer tube 2a Tip part 2b Guide hole 3 Retaining means 3a Small diameter part 3b Sealing surface 5 Connector 6 Connector 7 Gas supply pipe 10 Gas supply means 14 Gas leak detection means

Claims (3)

  A cryomedical device used for cryotherapy in which the affected part is necrotized by repeatedly supplying the frozen gas and the thawing gas to the probe inserted into the outer tube punctured in the affected part, and repeating the freezing and thawing of the affected part. A cryomedical device characterized in that the distal end portion of the outer tube is provided with a retaining means for preventing the probe from jumping out from the distal end of the outer tube due to high-pressure gas due to gas leakage generated in the outer tube.   A cryomedical device used for cryotherapy in which the affected part is necrotized by repeatedly supplying the frozen gas and the thawing gas to the probe inserted into the outer tube punctured in the affected part, and repeating the freezing and thawing of the affected part. An outer tube formed with a guide hole for inserting a guide needle for guiding the probe to the affected part, and a detachable housing in the outer tube, and a proximal end portion of the high pressure gas supply source via the connector A probe connected to the outer tube, and a retaining means provided at a distal end portion of the outer tube to prevent the probe from jumping out from the distal end of the outer tube due to high-pressure gas due to gas leakage generated in the outer tube, By electrically detecting the disconnection of the connector, a gas leak detecting means for detecting a gas leak in the outer tube, and a gas leak signal detected by the gas leak detecting means Frozen medical instrument being characterized in that and a control means for stopping the supply of gas to the probe.   The retaining means includes a small-diameter portion that bulges on the inner peripheral surface on the distal end side of the outer tube and has an inner diameter smaller than the outer diameter of the probe, and a sealing surface on which the distal end portion of the probe can be closely contacted The cryomedical device according to claim 1 or 2 formed.

Images