Patent Description:
Primary aldosteronism is a hypertensive disease that occurs when an adenoma (tumor) that causes oversecretion of aldosterone, which is a vasopressor hormone, is formed in an adrenal gland.

As a treatment of primary aldosteronism, if oversecretion of aldosterone from one adrenal gland is detected, the adrenal gland having a tumor is removed.

If oversecretion of aldosterone from both adrenal glands is detected, because both adrenal glands cannot be removed, the patient needs to continue taking an antihypertensive agent.

Recently, as a treatment method for primary aldosteronism that causes oversecretion of aldosteronism, the following method has been introduced: after specifying an adrenal gland having abnormality by sampling blood from an adrenal gland vein (adrenal venous blood sampling) by using a catheter, the position of the adrenal gland is accurately identified from an X-ray image or the like, and a tumor is ablated by inserting a bipolar RF (radiofrequency) needle from the back of the patient (see NPL <NUM> listed below).

However, although the treatment method described above is less invasive than an operation of removing an adrenal gland, the burden on a patient is still heavy.

Moreover, because the left adrenal gland is near the pancreas and the intestinal tract, a manipulation of inserting a bipolar RF needle into a tumor in the left adrenal gland from the back is anatomically difficult.

In order to solve such a problem, the inventor examined performing an ablation treatment by transvenously introducing an ablation needle into an adrenal gland, and proposed an ablation needle device that includes: an injection needle that is made of a metal and that is composed of a sharply-pointed tubular distal end portion and a tubular proximal end portion that has a lumen communicating with and having substantially the same diameter as a lumen of the distal end portion; and a grip portion that is attached to the proximal end side of the injection needle, in which the proximal end portion of the injection needle is given flexibility by forming a helical slit in at least a distal end region thereof, an outer surface of the proximal end portion is coated with a resin and the distal end of the distal end portion of the injection needle is closed, a plurality of fine holes that communicate with the lumen of the distal end portion are formed in an outer surface of the distal end portion including the closed part, and a liquid injection port for supplying liquid to the lumen of the injection needle is provided in the grip portion (see PTL <NUM> listed below).

In the ablation needle device, an electrode is constituted by the distal end portion of the injection needle that is not coated with a resin, and the length of the electrode constituted by the distal end portion is about <NUM> to <NUM>, which is preferable for treatment of a microadenoma.

With the ablation needle device, because the injection needle can be made flexible by reducing the rigidity in a distal end region of the proximal end portion of the injection needle to a certain level by forming the helical slit, the injection needle can be caused to follow the shape of a blood vessel extending to an adrenal gland without injuring a vascular wall and the distal end portion of the injection needle can be caused to reach a tumor site in the adrenal gland.

Moreover, because the plurality of fine holes that communicate with the lumen are formed in the outer surface of the distal end portion of the injection needle, a region around the distal end portion can be irrigated by ejecting the liquid, which is supplied to the lumen of the injection needle, from the plurality of fine holes, and a biological tissue or a thrombus can be prevented from adhering to a surface of the distal end portion (electrode) of the injection needle.

Accordingly, by using the ablation needle device, a transvenous ablation treatment, which is a new treatment method for primary aldosteronism, can be reliably performed. An ablation needle device having the features according to the preamble of claim <NUM>, is for instance known from <CIT>.

For example, in a case where it is necessary to ablate the entirety of an adrenal gland, such as a case where the entirety of the adrenal gland has a tumor, it is desirable to increase the size of an ablation region to be ablated by using a high-frequency electric current. In order to increase the size of the ablation region, it is necessary to increase the length of the electrode (to, for example, about <NUM>).

However, because a slit is not formed in the electrode (the distal end portion of the injection needle) of the ablation needle device described in PTL <NUM>, when the length of the electrode is increased, the rigidity of the injection needle including such an electrode increases and the flexibility decreases, the injection needle cannot follow the complex shape of a blood vessel, and therefore the injection needle may penetrate into a guiding catheter or a vascular wall while being introduced into an adrenal gland.

Therefore, it is desirable to provide an ablation needle device including a flexible and long electrode.

Moreover, as the length of the electrode of the ablation needle device is increased, it is necessary to increase the amount of cooling water (saline solution) that is irrigated in order to cool the electrode.

However, when a relatively large amount of cooling water for the size of an organ (adrenal gland) to be treated is irrigated, there is a risk of swelling or expansion of the organ, spreading of tumor tissues, and the like.

Furthermore, as the length of the electrode of the ablation needle device is increased, nonuniform cooling in the longitudinal direction of the electrode may occur.

The present invention has been made under the circumstances described above.

An object of the present invention is to provide an ablation needle device that can maintain the flexibility (bendability) of an injection needle including an electrode even when the length of the electrode constituted by a distal end portion of the injection needle is set to be large, that can sufficiently cool the electrode while avoiding a risk that occurs when cooling liquid is irrigated during ablation, and that can perform cooling with small nonuniformity in the longitudinal direction of the electrode.

Another object of the present invention is to provide an ablation needle device that can be particularly preferably used for a treatment method of performing a high-frequency ablation of an adrenal gland tumor by transvenously introducing an injection needle into an adrenal gland, and in particular, for a treatment method of ablating the entirety of an adrenal gland.

A still another object of the present invention is to provide a high-frequency ablation treatment system that can be preferably used for a treatment method of performing a high-frequency ablation of a tumor.

With the ablation needle device having such a configuration, because the helical slit is formed not only in the proximal end portion of the hollow needle but also in the distal end portion constituting the electrode, the hollow needle (injection needle) including the electrode can be made flexible even when the length of the electrode is set to be large for the purpose of increasing the size of an ablation region, the hollow needle can be caused to follow the complex shape of a blood vessel without injuring a vascular wall and the like, and the electrode can be caused to reliably reach a target site.

Moreover, by ejecting cooling liquid from the distal end openings of the plurality of cooling liquid introducing pipes in the inside of the distal end portion of the hollow needle whose liquid-tightness is ensured, the electrode can be sufficiently cooled (inner cooling) while completely avoiding a risk that occurs when cooling liquid is irrigated.

Furthermore, because the distal end opening positions (ejection positions of cooling liquid) of the plurality of cooling liquid introducing pipes differ from each other in the distal-proximal direction of the hollow needle in the inside of the distal end portion of the hollow needle constituting the electrode, cooling with small nonuniformity in the longitudinal direction of the electrode can be performed even when the length of the electrode is set to be large.

(<NUM>) In the ablation needle device according to the present invention, preferably, the hub includes a liquid flow port that includes both of the injection port and the discharge port.

(<NUM>) The ablation needle device according to the present invention preferably comprises: a first cooling liquid introducing pipe that extends in the inside of the hub and the inside of the hollow needle, that has a distal end positioned in the inside of the distal end portion of the hollow needle, and that ejects liquid injected from the injection port from a distal end opening thereof; and.

With the ablation needle device having such a configuration, because the distal end opening position (ejection position of cooling liquid) of the first cooling liquid introducing pipe and the distal end opening position (ejection position of cooling liquid) of the second cooling liquid introducing pipe differ from each other in the distal-proximal direction of the hollow needle in the inside of the distal end portion of the hollow needle constituting the electrode, cooling with small nonuniformity in the longitudinal direction of the electrode can be performed even when the length of the electrode is set to be large.

(<NUM>) In the ablation needle device described in (<NUM>), preferably, the distal end opening of the first cooling liquid introducing pipe is positioned in an inside of a vicinity of a distal end of the distal end portion of the hollow needle, and the distal end opening of the second cooling liquid introducing pipe is positioned in an inside of an approximately middle part (substantially middle part) or a vicinity of a proximal end of the distal end portion of the hollow needle.

With the ablation needle device having such a configuration, cooling liquid ejected from the distal end opening of the first cooling liquid introducing pipe can cool mainly a distal end part of the distal end portion (electrode) of the hollow needle, and cooling liquid ejected from the distal end opening of the second cooling liquid introducing pipe can cool mainly a proximal end part of the distal end portion (electrode) of the hollow needle.

(<NUM>) In the ablation needle device according to the present invention, preferably, the distal end of the hollow needle is closed by a distal end tip that is made of a resin, and
a temperature measuring junction of the thermocouple is embedded in the distal end tip.

With the ablation needle device having such a configuration, because the temperature measuring junction of the thermocouple is embedded in the distal end tip made of a resin having low thermal conductivity, the temperature measuring junction is not easily influenced by temperature variation of the electrode (the distal end portion of the hollow needle), and can accurately measure the temperature of a tissue around the electrode.

(<NUM>) In the ablation needle device according to the present invention, preferably, a lumen tube that forms a guidewire lumen extends in the inside of the hollow needle.

With the ablation needle device having such a configuration, the electrode (the distal end portion of the hollow needle) can be caused to rapidly and reliably reach a target site by using a guidewire.

(<NUM>) In the ablation needle device according to the present invention, preferably, a length of the electrode constituted by the distal end portion of the hollow needle is <NUM> to <NUM>, and particularly <NUM> to <NUM>.

It is particularly effective to use the configuration of the present invention in an ablation needle device including such a long electrode.

(<NUM>) In the ablation needle device according to the present invention, preferably, a pitch of the slit formed in the hollow needle continuously or intermittently decreases in a distal end direction.

With such an ablation needle device, the rigidity of the hollow needle can be continuously or intermittently reduced in the distal end direction, and thus the needle device has particularly good operability during introduction of the hollow needle into a target site.

(<NUM>) In the ablation needle device according to the present invention, preferably, in at least the region in which the slit is formed in the distal end portion, the waterproofing is applied by forming a waterproof seal coating on the inner surface of the hollow needle.

With such an ablation needle device, because waterproofing can be reliably applied to the inner peripheral surface of a region of the distal end portion having the outer surface that is exposed (that is not resin-coated) and in which the slit is formed, the liquid-tightness of the inside of the hollow needle can be ensured.

(<NUM>) In the ablation needle device described in (<NUM>), preferably, the waterproof seal coating is formed by increasing a diameter of a heat-expandable resin tube, which is in a state of having been inserted to the inside of the hollow needle, by heating the heat-expandable resin tube.

(<NUM>) The ablation needle device according to the present invention can be preferably used for performing an ablation treatment of an adrenal gland tumor by transvenously introducing the hollow needle into an adrenal gland.

(<NUM>) A high-frequency ablation treatment system according to the present invention comprises: the ablation needle device according to the present invention;.

With the ablation needle device according to the present invention, the hollow needle including the electrode can be made flexible even when the length of the electrode constituted by the distal end portion of the hollow needle is set to be large.

Moreover, during ablation, the electrode can be sufficiently cooled while completely avoiding the aforementioned risk, which occurs when cooling liquid is irrigated, by ensuring the liquid-tightness of the inside of the hollow needle and performing inner cooling.

Furthermore, efficient cooling with small nonuniformity in the longitudinal direction of the electrode can be performed even when the length of the electrode is set to be large.

With the high-frequency ablation treatment system according to the present invention, a high-frequency ablation treatment of a tumor can be reliably performed.

An ablation needle device <NUM> according to the present embodiment is an ablation needle device for performing a high-frequency ablation treatment of an adrenal gland tumor by transvenously introducing an injection needle (hollow needle) into an adrenal gland, including: a hollow needle <NUM> that is made of a metal and that is composed of a proximal end portion <NUM> having an outer surface that is insulation-coated with a resin <NUM> and a distal end portion <NUM> having an outer surface that is exposed and thus constituting an electrode; a hub (branched hub) <NUM> that is attached to a proximal end side of the hollow needle <NUM> and that includes a liquid flow port <NUM> (one port that includes both of a liquid injection port and a liquid discharge port), a connection port <NUM> of an electric connector, and a guidewire port <NUM>; an electric connector <NUM> that is electrically connected to the hollow needle <NUM> in order to supply a high-frequency electric current to the electrode; a thermocouple <NUM> that is inserted to the inside of the hub <NUM> from the connection port <NUM> of electric connector in order to measure the temperature of a tissue around the electrode and that extends in the inside of the hub <NUM> and the inside of the hollow needle <NUM>; a first cooling liquid introducing pipe <NUM> that extends in the inside of the hub <NUM> and the inside of the hollow needle <NUM>, that has a distal end <NUM> positioned in the inside of the distal end portion <NUM> of the hollow needle <NUM>, and that ejects cooling liquid injected from the flow port <NUM> to the inside of the hub <NUM> from a distal end opening thereof; a second cooling liquid introducing pipe <NUM> that extends in the inside of the hub <NUM> and the inside of the hollow needle <NUM> together with the first cooling liquid introducing pipe <NUM>, that has a distal end <NUM> positioned in the inside of the distal end portion <NUM> of the hollow needle <NUM>, and that ejects cooling liquid injected from the flow port <NUM> to the inside of the hub <NUM> from a distal end opening thereof; and a lumen tube <NUM> that extends in the inside of the hollow needle <NUM> and forms a guidewire lumen, wherein the hollow needle <NUM> is given flexibility by forming a helical slit <NUM> in a distal end region 12A of the proximal end portion <NUM> of the hollow needle <NUM> and the distal end portion <NUM> adjacent thereto, wherein the liquid-tightness of the inside of the hollow needle <NUM> is ensured by forming a waterproof seal coating <NUM> on an inner surface of the hollow needle <NUM> and by closing the distal end of the hollow needle <NUM> with a distal end tip <NUM> made of a resin, wherein a temperature measuring junction (temperature sensor) <NUM> of the thermocouple <NUM> is embedded in the distal end tip <NUM> and a distal end part of the lumen tube <NUM> extends through the distal end tip <NUM> and forms an opening, and wherein the distal end opening position of the first cooling liquid introducing pipe <NUM> and the distal end opening position of the second cooling liquid introducing pipe <NUM> differ from each other in the distal-proximal direction of the hollow needle <NUM>.

In <FIG> and <FIG>, <NUM> to <NUM> respectively denote extension tubes that extend out from the ports <NUM>, <NUM>, and <NUM> of the hub <NUM>; and <NUM>, <NUM>, and <NUM> respectively denote connectors that are attached to proximal ends of the extension tubes <NUM>, <NUM>, and <NUM>.

The ablation needle device <NUM> according to the present embodiment includes the hollow needle (injection needle) <NUM>, the hub <NUM>, the electric connector <NUM>, the thermocouple <NUM>, the first cooling liquid introducing pipe <NUM>, the second cooling liquid introducing pipe <NUM>, and the lumen tube <NUM>.

The hollow needle <NUM> of the ablation needle device <NUM> is a hollow needle that is made of a metal and that is composed of the proximal end portion <NUM> having an outer surface that is insulation-coated with the coating resin <NUM> and the distal end portion <NUM> having an outer surface that is exposed and thus constituting an electrode.

Examples of a metal material of the hollow needle <NUM> include stainless steel, NiTi, β titanium, platinum iridium, and the like.

The outside diameter of the hollow needle <NUM> (the distal end portion <NUM> and the proximal end portion <NUM>) is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The inside diameter of the hollow needle <NUM> (the distal end portion <NUM> and the proximal end portion <NUM>) is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The length of the hollow needle <NUM> is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The outer surface of the proximal end portion <NUM> of the hollow needle <NUM> is insulation-coated with the coating resin <NUM>, and thus a high-frequency electric current does not flow between the proximal end portion <NUM> and a patient plate.

The film thickness of the coating resin <NUM> is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The coating resin <NUM> is formed by decreasing the diameter of a heat-shrinkable resin tube, which is in a state that the proximal end portion <NUM> has been inserted to the inside thereof, by heating the heat-shrinkable resin tube.

Examples of a heat-shrinkable resin tube for forming the coating resin <NUM> include a polyether block amide copolymer resin (PEBAX (registered trademark)).

The outer surface of the distal end portion <NUM> of the hollow needle <NUM> is not resin-coated and is exposed.

Thus, a high-frequency electric current flows between the distal end portion <NUM> and the patient plate, and the distal end portion <NUM> functions as an electrode.

The length of the distal end portion <NUM> of the hollow needle <NUM> (L11 shown in <FIG>) is preferably <NUM> or larger, more preferably <NUM> to <NUM>, and further preferably <NUM> to <NUM>; and a preferable example may be <NUM>.

When the length of the distal end portion <NUM> is <NUM> or larger, a heat generating region due to a high-frequency electric current (the size of an ablation region) can be increased, and a sufficient treatment effect can be obtained even when a treatment method of ablating the entirety of an adrenal gland is performed.

In the hollow needle <NUM>, the helical slit <NUM> is formed in the distal end region 12A of the proximal end portion <NUM> and in the distal end portion <NUM> adjacent thereto.

Because the helical slit <NUM> is formed not only in the distal end region 12A of the proximal end portion <NUM> of the hollow needle <NUM> but also in the distal end portion <NUM> constituting an electrode, even when the length of the electrode (the distal end portion <NUM>) is increased, the hollow needle <NUM> including the electrode has high flexibility (bendability) and can be easily caused to follow the shape of a blood vessel extending to an adrenal gland.

The length of the distal end region 12A, which is a region of the proximal end portion <NUM> in which the slit <NUM> is formed, is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The slit <NUM> in the distal end portion <NUM> need not be formed over the entire length of the distal end portion <NUM>, as long as flexibility (bendability) of the hollow needle <NUM> including the electrode can be ensured. In the present embodiment, the slit <NUM> is not formed in a region within at least about <NUM> to <NUM> from the distal end, including a part to which the distal end tip <NUM> is attached.

A method for forming the slit <NUM> is not particularly limited, and laser machining, electrical discharge machining, chemical etching, cutting, or the like may be used.

The width of the slit <NUM> is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The helical slit <NUM> formed in the hollow needle <NUM> is a through-slit that extends from the outer peripheral surface to the inner peripheral surface of a metal pipe. A slit formed in a hollow needle in the present invention may be a blind slit that does not extend to the inner peripheral surface.

In a region of the hollow needle <NUM> (the distal end portion <NUM> and the proximal end portion <NUM>) in which the slit <NUM> is formed, the pitch of the slit <NUM> continuously decreases in the distal end direction. Thus, the rigidity of the hollow needle <NUM> can be continuously (smoothly) reduced in the distal end direction, and thus the needle device has particularly good operability during introduction of the hollow needle <NUM> into an adrenal gland. In the present invention, the pitch of entirety of the slit formed in the hollow needle may be regular.

As illustrated in <FIG>, the waterproof seal coating <NUM> is formed on the inner peripheral surface of the hollow needle <NUM> over the entire length thereof, and, because waterproofing is applied in this manner, cooling liquid in the inside of the hollow needle <NUM> does not leak out from the slit <NUM> formed in the distal end portion <NUM>.

The film thickness of the waterproof seal coating <NUM> is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The waterproof seal coating <NUM> is formed by increasing the diameter of a heat-expandable resin tube, which is in a state of having been inserted to the inside of the hollow needle <NUM>, by heating the heat-expandable resin tube.

Examples of a heat-expandable resin tube for forming the waterproof seal coating <NUM> include, although not particularly limited as long as the tube has heat-expandability, include a tube made of a polyurethane resin, an FEP resin, or the like.

In the present embodiment, the waterproof seal coating <NUM> is formed on the inner peripheral surface of the hollow needle <NUM> over the entire length of the hollow needle <NUM>. However, because the waterproofing ability (effect of preventing leaking out of cooling liquid from the slit <NUM>) of the proximal end portion <NUM> of the hollow needle <NUM> is ensured by the coating resin <NUM>, the waterproof seal coating <NUM> may be formed only on the inner peripheral surface of a region of the distal end portion <NUM> of the hollow needle <NUM> in which the slit <NUM> is formed.

As illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, the distal end of the hollow needle <NUM> (the distal end portion <NUM>) is closed by the distal end tip <NUM> made of a resin, and thus cooling liquid does not leak out from the distal end of the hollow needle <NUM>.

Examples of a resin from which the distal end tip <NUM> is made include a PEEK resin, nylon, polycarbonate, and the like.

As illustrated in <FIG> and <FIG>, the hub <NUM> of the ablation needle device <NUM>, which is attached to the proximal end side of the hollow needle <NUM>, is a branched hub that includes the liquid flow port <NUM>, the connection port <NUM> of an electric connector, and the guidewire port <NUM>.

The liquid flow port <NUM> includes both of a "liquid injection port" for injecting cooling liquid to the inside of the hub <NUM> and supplying the cooling liquid to the inside of the hollow needle <NUM>, and a "liquid discharge port" for discharging, from the hub <NUM>, cooling liquid that has returned to the inside of the hub <NUM> from the inside of the hollow needle <NUM> after cooling the electrode.

As illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, a first extension tube <NUM> extends out from the flow port <NUM>.

As illustrated in <FIG> and <FIG>, a proximal end portion of the first cooling liquid introducing pipe <NUM> and a proximal end portion of the second cooling liquid introducing pipe <NUM>, which will be described below, are inserted into the distal end opening of the first extension tube <NUM> positioned in the inside of the hub <NUM>.

A connector <NUM> (liquid injection connector) is attached to the proximal end of the first extension tube <NUM>, and the first extension tube <NUM> is coupled, via the connector <NUM>, to a cooling liquid supply pump of a cooling liquid circulation mechanism (and thus the flow port <NUM> includes a liquid injection port).

Here, examples of cooling liquid, which flows through the first extension tube <NUM> and is injected from the liquid flow port <NUM>, include a high-concentration saline solution such as a saturated saline solution. The temperature of cooling liquid (saturated saline solution) injected is about -<NUM> to -<NUM>.

As illustrated in <FIG>, <FIG>, and <FIG>, a second extension tube <NUM> extends out from the flow port <NUM> together with the first extension tube <NUM>.

The second extension tube <NUM> communicates with the inside of the hollow needle <NUM>, because the distal end thereof is open in the inside of the hub <NUM>.

A connector <NUM> (liquid discharge connector) is attached to the proximal end of the second extension tube <NUM>, and the second extension tube <NUM> is coupled, via the connector <NUM>, to a liquid recovery tank of a cooling liquid circulation mechanism (and thus the flow port <NUM> includes a liquid discharge port).

The connection port <NUM> of the electric connector is a port for inserting a lead of the electric connector <NUM> and the thermocouple <NUM> to the inside of the hub <NUM>.

As illustrated in <FIG> and <FIG> and <FIG>, a third extension tube <NUM> extends out from the connection port <NUM>. The lead of the electric connector <NUM> and the thermocouple <NUM> extend through the inside of the third extension tube <NUM>, are guided to the connection port <NUM>, and are inserted to the inside of the hub <NUM>.

As illustrated in <FIG>, <FIG>, and <FIG>, a fourth extension tube <NUM> extends out from the guidewire port <NUM>.

As illustrated in <FIG>, a proximal end portion of the lumen tube <NUM> forming a guidewire lumen is inserted into a distal end opening of the fourth extension tube <NUM> positioned in the inside of the hub <NUM>.

A connector <NUM> for inserting a guidewire is attached to the proximal end of the fourth extension tube <NUM>.

The electric connector <NUM> of the ablation needle device <NUM> is a connector for supplying a high-frequency electric current to the electrode, which is constituted by the distal end portion <NUM> of the hollow needle <NUM>, by connecting this to a high-frequency electric power source device.

The lead (not shown) of the electric connector <NUM> extends through the inside of the third extension tube <NUM> and is inserted from the connection port <NUM> to the inside of the hub <NUM>. The distal end of the electric connector <NUM> is fixed, for example, to an inner peripheral surface (metal surface that is exposed by peeling off the waterproof seal coating <NUM>) of the proximal end portion of the hollow needle <NUM> by welding, and thus the electric connector <NUM> and the hollow needle <NUM> are electrically connected.

The electric connector <NUM> is used also as a thermocouple connector. The thermocouple <NUM> of the ablation needle device <NUM> is used to measure the temperature of a tissue around the electrode.

The thermocouple <NUM> connected to the electric connector <NUM> (thermocouple connector) extends through the inside of the third extension tube <NUM>, is inserted from the connection port <NUM> to the inside of the hub <NUM> and extends in the inside of the hub <NUM> as illustrated in <FIG> and <FIG>, and extends in the inside of the hollow needle <NUM> as illustrated in <FIG>.

The temperature measuring junction (temperature sensor) <NUM> of the thermocouple <NUM> is embedded in the distal end tip <NUM> made of a resin and closing the distal end of the hollow needle <NUM>.

Because the temperature measuring junction <NUM> of the thermocouple <NUM> is embedded in the distal end tip <NUM> made of a resin having low thermal conductivity, the temperature measuring junction <NUM> is not easily influenced by temperature variation due to heating and cooling of the electrode (the distal end portion <NUM> of the hollow needle <NUM>) having high thermal conductivity, and can accurately measure the temperature of a tissue around the electrode.

In the ablation needle device <NUM> according to the present embodiment, the two cooling liquid introducing pipes <NUM> and <NUM>, whose distal end opening positions differ, are provided in order to ensure a flow path of cooling liquid in the inside of the hollow needle <NUM>.

As illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, the first cooling liquid introducing pipe <NUM> of the ablation needle device <NUM> extends in the inside of the hub <NUM> and the inside of the hollow needle <NUM>.

As illustrated in <FIG>, the distal end <NUM> of the first cooling liquid introducing pipe <NUM> is positioned in the inside of the vicinity of the distal end of the distal end portion <NUM> of the hollow needle <NUM>.

As illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, the second cooling liquid introducing pipe <NUM> of the ablation needle device <NUM> extends parallel to the first cooling liquid introducing pipe <NUM> in the inside of the hub <NUM> and the inside of the hollow needle <NUM>.

As illustrated in <FIG>, the distal end <NUM> of the second cooling liquid introducing pipe <NUM> is positioned in the inside of an approximately middle part of the distal end portion <NUM> of the hollow needle <NUM> (on the proximal end side relative to the distal end <NUM> of the first cooling liquid introducing pipe <NUM>).

As illustrated in <FIG> and <FIG>, the proximal end portion of the first cooling liquid introducing pipe <NUM> and the proximal end portion of the second cooling liquid introducing pipe <NUM> are inserted into the distal end opening of the first extension tube <NUM> coupled to a cooling liquid supply pump.

When cooling liquid is supplied (cooling liquid is injected from the flow port <NUM>) to a lumen of the first cooling liquid introducing pipe <NUM> and a lumen of the second cooling liquid introducing pipe <NUM> through the first extension tube <NUM>, the cooling liquid is ejected from the distal end opening of the first cooling liquid introducing pipe <NUM> positioned in the vicinity of the distal end of the distal end portion <NUM>, and is ejected from the distal end opening of the second cooling liquid introducing pipe <NUM> positioned in the approximately middle part of the distal end portion <NUM>.

Cooling liquid ejected from the distal end opening of the first cooling liquid introducing pipe <NUM> can cool mainly a distal end part of the distal end portion <NUM> constituting the electrode, and cooling liquid ejected from the distal end opening of the second cooling liquid introducing pipe <NUM> can cool mainly a proximal end part of the distal end portion <NUM>.

Because the distal end opening position of the first cooling liquid introducing pipe <NUM> and the distal end opening position of the second cooling liquid introducing pipe <NUM> differ from each other (the ejection positions of cooling liquid in the inside of the electrode differ) in this manner, cooling with small nonuniformity in the longitudinal direction of the electrode can be performed even when the length of the electrode constituted by the distal end portion <NUM> of the hollow needle <NUM> is large.

Moreover, because the two cooling liquid introducing pipes <NUM> and <NUM> are caused to extend in the inside of the hollow needle <NUM> in which the lumen tube <NUM> illustrated in <FIG> extends, the total cross-sectional area of these introducing pipes can be made larger than the cross-sectional area of one cooling liquid introducing pipe in a case where the introducing pipe is caused to extend.

Cooling liquid ejected from the distal end opening of the first cooling liquid introducing pipe <NUM> and the distal end opening of the second cooling liquid introducing pipe <NUM> cools the electrode constituted by the distal end portion <NUM> of the hollow needle <NUM> from the inside (inner cooling), then returns from the inside of the hollow needle <NUM> to the inside of the hub <NUM>, and flows in the proximal-end direction in the inside of the second extension tube <NUM>; and thus the cooling liquid is discharged from the flow port <NUM> and recovered to the liquid recovery tank.

As illustrated in <FIG>, the lumen tube <NUM> of the ablation needle device <NUM> extends in the inside of the hollow needle <NUM> and forms a guidewire lumen.

A distal end part of the lumen tube <NUM> extends through the distal end tip <NUM> made of a resin, and forms an opening, which serves as a guidewire port, at the distal end of the distal end tip <NUM>. Also with this configuration, the liquid-tightness of the inside of the hollow needle <NUM> is ensured.

By inserting a guidewire into the guidewire lumen formed by the lumen tube <NUM> and introducing the ablation needle device <NUM>, the electrode (the distal end portion <NUM> of the hollow needle <NUM>) can be caused to rapidly and reliably reach a target site.

With the ablation needle device <NUM> according to the present embodiment, by being mounted in a high-frequency ablation treatment system described below, a high-frequency ablation treatment of an adrenal gland tumor can be performed. Moreover, because the high-frequency ablation treatment is a transvenous ablation treatment, it can be comparatively easily performed for a tumor in a left adrenal gland, which has been difficult to treat with an existing manipulation of inserting a high-frequency needle from the back.

Because the helical slit <NUM> is formed not only in the proximal end portion <NUM> of the hollow needle <NUM> but also in the distal end portion <NUM> of the hollow needle <NUM> constituting the electrode, the hollow needle <NUM> including the electrode can be made flexible even when the length of the electrode is increased, and therefore the hollow needle <NUM> can be caused to follow the shape of a blood vessel extending to an adrenal gland, and the electrode can be caused to reach a tumor site in the adrenal gland without injuring a vascular wall. By increasing the length of the electrode, the size of an ablation region can be increased, and thus even a manipulation of ablating the entirety of an adrenal gland can be efficiently performed.

In a state in which the liquid-tightness of the inside of the hollow needle <NUM> is ensured by forming the waterproof seal coating <NUM> on the inner surface of the hollow needle <NUM> and closing the distal end with the distal end tip <NUM>, by ejecting cooling liquid from the distal end opening of the first cooling liquid introducing pipe <NUM> and the distal end opening of the second cooling liquid introducing pipe <NUM>, the electrode can be sufficiently cooled while avoiding a risk that occurs when cooling liquid is irrigated by ensuring the liquid-tightness of the inside and performing inner-cooling.

Because, in the inside of the hollow needle <NUM>, the distal end opening position of the first cooling liquid introducing pipe <NUM> is positioned in the vicinity of the distal end of the distal end portion <NUM> and the distal end opening position of the second cooling liquid introducing pipe <NUM> is positioned in an approximately middle part of the distal end portion <NUM>, cooling with small nonuniformity in the longitudinal direction of the electrode can be performed even when the length of the electrode is increased.

Because the distal end tip that closes the distal end of the hollow needle <NUM> is made of a resin and the temperature measuring junction of the thermocouple <NUM> is embedded in the distal end tip <NUM>, the temperature measuring junction is not easily influenced by temperature variation of the electrode (the distal end portion <NUM> of the hollow needle <NUM>) having high thermal conductivity and can accurately measure the temperature of a tissue around the electrode.

Heretofore, an embodiment of an ablation needle device according to an embodiment of the present invention has been described. However, the present invention is not limited to these and can be modified in various ways.

For example, a hub of an ablation needle device according to the present invention may include, separately, an injection port for injecting cooling liquid and supplying the cooling liquid to the inside of the hollow needle, and a discharge port for discharging liquid that has cooled the electrode and returned from the inside of the hollow needle.

The number of cooling liquid introducing pipes (cooling liquid introducing pipes) of an ablation needle device according to the present invention is not limited to two and may be three or larger.

An ablation needle device according to the present invention can be used to treat a tumor other than an adrenal gland tumor (such as a liver cancer).

A high-frequency ablation treatment system <NUM> according to an embodiment illustrated in <FIG> includes: the ablation needle device <NUM> described above; a high-frequency electric power source device <NUM> connected to the electric connector <NUM> of the ablation needle device <NUM>; a patient plate <NUM> connected to the high-frequency electric power source device <NUM>; a guiding catheter <NUM> for guiding the electrode of the ablation needle device <NUM> to an adrenal gland AG of a patient P; and a cooling liquid circulation mechanism <NUM> that includes a cooling liquid supply pump <NUM> that injects cooling liquid into the flow port (injection port) of the hub <NUM> through the first extension tube <NUM> in order to cool the electrode of the ablation needle device <NUM>, and a recovery tank <NUM> that recovers liquid that has cooled the electrode and returned from the inside of the hollow needle <NUM> to the inside of the hub <NUM> from the flow port (discharge port) through the second extension tube <NUM> and cools the liquid again. In the figure, <NUM> denotes a guidewire.

As illustrated in <FIG>, the electric connector <NUM> of the ablation needle device <NUM> is connected to a needle device connector <NUM> of the high-frequency electric power source device <NUM>. A patient plate connector <NUM> of the high-frequency electric power source device <NUM> is connected to the patient plate <NUM>.

Thus, it is possible to cause a high-frequency electric current to flow between the distal end portion (electrode) of the hollow needle <NUM> of the ablation needle device <NUM> and the patient plate <NUM> (to perform a high-frequency ablation treatment of an adrenal gland tumor).

The first extension tube <NUM>, which extends out from the flow port (injection port) of the hub <NUM> of the ablation needle device <NUM>, is connected to the supply pump <NUM> of the cooling liquid circulation mechanism <NUM>.

Thus, when a high-frequency ablation treatment is being performed, cooling liquid from the supply pump <NUM> can be injected from the flow port (injection port) to the inside of the hub <NUM> and supplied to the inside of the hollow needle <NUM>, and the electrode formed from the distal end portion of the hollow needle <NUM> can be cooled from the inside thereof (inner cooling).

The second extension tube <NUM>, which extends out from the flow port (discharge port) provided in the hub <NUM> of the ablation needle device <NUM>, is connected to the recovery tank <NUM> of the cooling liquid circulation mechanism <NUM>.

Thus, liquid that has cooled the electrode and returned from the inside of the hollow needle <NUM> to the inside of the hub <NUM> can be discharged from the flow port (discharge port) to the outside of the hub <NUM>, and can be recovered to the recovery tank <NUM> through the second extension tube <NUM>.

The liquid recovered to the recovery tank <NUM> is cooled (again) in the recovery tank <NUM>, and then injected by the supply pump <NUM> to the inside of the hub <NUM>.

The guiding catheter <NUM> of the high-frequency ablation treatment system <NUM> is inserted in advance so that the distal end thereof is positioned in (the vicinity of) the adrenal gland AG of the patient P in order to guide the distal end portion of the hollow needle <NUM> of the ablation needle device <NUM> to the adrenal gland.

The guiding catheter <NUM> schematically illustrated in <FIG> has different shapes respectively for a right adrenal gland and a left adrenal gland in accordance with the difference between the shapes of blood vessels extending to the adrenal glands.

<FIG> illustrates the shape of a distal end part of a guiding catheter 160R for a right adrenal gland. <FIG> illustrates the shape of a distal end part of a guiding catheter <NUM> for a left adrenal gland.

The guiding catheters 160R and <NUM> illustrated in <FIG> both have a plurality of curved portions.

As illustrated in <FIG>, the guiding catheter 160R for a right adrenal gland illustrated in <FIG> is inserted through an inferior vena cava IVC and a right adrenal gland vein so that the distal end thereof is positioned in (the vicinity of) a right adrenal gland RAG. As illustrated in <FIG>, the guiding catheter <NUM> for a left adrenal gland illustrated in <FIG> is inserted through the inferior vena cava IVC, a left renal vein LRV, and a left adrenal gland vein so that the distal end thereof is positioned in (the vicinity of) a left adrenal gland LAG.

In <FIG> and <FIG>, RK denotes a right kidney and LK denotes a left kidney.

The outside diameter of the guiding catheter <NUM> (160R, <NUM>) is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The inside diameter of the guiding catheter <NUM> is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

The length of the guiding catheter <NUM> is, for example, <NUM> to <NUM>, and preferably <NUM> to <NUM>.

As the guiding catheter <NUM> (160R, <NUM>), a catheter that has been used to sample blood from an adrenal gland vein (adrenal gland vein sampling) can be used.

With the high-frequency ablation treatment system <NUM> according to the present embodiment, by causing a high-frequency electric current to flow between the distal end portion of the hollow needle <NUM> of the ablation needle device <NUM> and the patient plate <NUM>, a high-frequency ablation treatment of an adrenal gland tumor (minimally-invasive transvenous ablation treatment) can be performed.

When the high-frequency ablation treatment is being performed, by ejecting cooling liquid from the supply pump <NUM> of the cooling liquid circulation mechanism <NUM> from the distal end openings of the first cooling liquid introducing pipe and the second cooling liquid introducing pipe at the distal end portion of the hollow needle <NUM> of the ablation needle device <NUM>, the electrode formed from the distal end portion of the hollow needle <NUM> can be cooled from the inside (inner cooling).

Claim 1:
An ablation needle device (<NUM>) for performing a high-frequency ablation treatment of a tumor, comprising:
a hollow needle (<NUM>) that is made of a metal and that is composed of a proximal end portion (<NUM>) having an outer surface that is insulation-coated with a resin and a distal end portion (<NUM>) having an outer surface that is exposed and thus constituting an electrode;
a hub (<NUM>) that is attached to a proximal end side of the hollow needle (<NUM>) and that includes a liquid injection port (<NUM>) for injecting liquid for cooling the electrode and supplying the liquid to an inside of the hollow needle (<NUM>),
an electric connector (<NUM>) that is electrically connected to the hollow needle (<NUM>) in order to supply a high-frequency electric current to the electrode;
a thermocouple (<NUM>) that extends in the inside of the hollow needle (<NUM>) in order to measure a temperature of a tissue around the electrode;
wherein the hollow needle is given flexibility by forming a helical slit (<NUM>) in at least a distal end region of the proximal end portion (<NUM>) of the hollow needle (<NUM>) and the distal end portion (<NUM>),
wherein a liquid-tightness of the inside of the hollow needle (<NUM>) is ensured by applying waterproofing to an inner surface of the hollow needle in at least a region in which the slit (<NUM>) is formed in the distal end portion,
wherein the ablation needle device is characterized by the hub further including a liquid discharge port (<NUM>) for discharging liquid that has cooled the electrode and returned from the inside of the hollow needle;
wherein the liquid-tightness of the inside of the hollow needle is further ensured by closing a distal end of the hollow needle (<NUM>), and
wherein the ablation needle device further comprises a plurality of cooling liquid introducing pipes (<NUM>,<NUM>)each of which extends in an inside of the hub and the inside of the hollow needle (<NUM>), each of which has a distal end positioned in an inside of the distal end portion (<NUM>) of the hollow needle (<NUM>), and each of which ejects liquid injected from the injection port from a distal end opening thereof,
wherein distal end opening positions of the plurality of cooling liquid introducing pipes differ from each other in a distal-proximal direction of the hollow needle (<NUM>).