Ablation needle device, high-frequency ablation treatment system, and chemical ablation treatment system

An ablation needle device is a needle device intended for an ablation treatment of an adrenal tumor with transvenous introduction of an injection needle into an adrenal gland. The ablation needle device includes a metal injection needle including a pointed tubular distal portion and a tubular proximal portion, and a grip portion attached to a proximal side of the injection needle. The proximal portion of the injection needle is given flexibility by forming a helical slit in a distal region of the proximal portion. An outer surface of the proximal portion is coated with resin. A distal end of the distal portion of the injection needle is closed. A plurality of fine holes are formed in an outer surface of the distal portion including the closed part. The grip portion has a liquid-injection port for supplying liquid into the lumen of the injection needle.

TECHNICAL FIELD

The present invention relates to an ablation needle device intended for an ablation treatment of an adrenal tumor with transvenous introduction of an injection needle into an adrenal gland, and also relates to a high-frequency ablation treatment system and a chemical ablation treatment system each including such an ablation needle device.

BACKGROUND ART

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

In a treatment for primary aldosteronism, if there is oversecretion of aldosterone in one of the adrenal glands, the adrenal gland having the tumor is removed.

In contrast, if there is oversecretion of aldosterone in both of the adrenal glands, the patient needs to keep taking an antihypertensive drug because it is not allowed to remove both of the adrenal glands.

Recently, a treatment method for primary aldosteronism that causes oversecretion of aldosterone has been introduced, in which blood is sampled from an adrenal vein (adrenal venous sampling) with a catheter, which of the adrenal glands has abnormality is identified, the abnormal adrenal gland is accurately located through X-ray imaging or the like, a bipolar RF (radio-frequency) needle is inserted into the patient from his/her back, and the tumor is ablated.

CITATION LIST

Non Patent Literature

SUMMARY OF INVENTION

Technical Problem

In the above treatment method, the degree of invasion is lower than in the case of surgical removal of an adrenal gland, but the burden imposed on the patient is still heavy.

Furthermore, since the left adrenal gland is close to the pancreas and the intestinal tract, sticking a bipolar RF needle into a tumor in the left adrenal gland from the back is an anatomically difficult technique.

Such problems may be solved by an ablation treatment in which an ablation needle such as an RF needle is transvenously introduced into the adrenal gland.

However, a publicly known RF needle is highly rigid and less flexible and is incapable of following the complicated shapes of blood vessels. Therefore, such an RF needle may be stuck into a guiding catheter or a vascular wall before reaching the adrenal gland.

Moreover, if any biological tissue (adrenal tumor tissue) or thrombi adhere to the surface of the RF needle (an electrode) during ablation, the ablation treatment may become unable to continue.

Therefore, it is practically impossible to perform ablation treatment by transvenously introducing a publicly known RF needle into an adrenal gland.

The present invention has been conceived in view of the above circumstances.

An object of the present invention is to provide an ablation needle device that can be used for a transvenous ablation treatment, which is a novel treatment method for primary aldosteronism.

Another object of the present invention is to provide an ablation treatment system that can be used for the transvenous ablation treatment for primary aldosteronism.

Solution to Problem

(1) An ablation needle device according to the present invention is an ablation needle device intended for an ablation treatment of an adrenal tumor with transvenous introduction of an injection needle into an adrenal gland, the ablation needle device comprising:

a metal injection needle including a pointed tubular distal portion and a tubular proximal portion whose lumen communicates with a lumen of the distal portion and has substantially the same diameter as the lumen of the distal portion; and a grip portion attached to a proximal side of the injection needle,

wherein the proximal portion of the injection needle is given flexibility (bendability) by forming a helical slit at least in a distal region of the proximal portion, and an outer surface of the proximal portion is coated with resin,

wherein a distal end of the distal portion of the injection needle (a distal-end opening of a typical injection needle) is closed, and a plurality of fine holes communicating with the lumen of the distal portion are formed in an outer surface of the distal portion including the closed part, and

wherein the grip portion has a liquid-injection port for supplying liquid into the lumen of the injection needle (the lumen of the proximal portion and the lumen of the distal portion).

In such an ablation needle device, the rigidity of the distal region of the proximal portion of the injection needle is reduced to some extent by forming the helical slit therein. Therefore, the injection needle can be made flexible. Hence, the injection needle can be made to follow the shape of a blood vessel reaching the adrenal gland, and the distal portion of the injection needle can be made to reach a tumor site in the adrenal gland, without damaging the vascular wall.

Furthermore, since the plurality of fine holes communicating with the lumen are formed in the outer surface of the distal portion of the injection needle, a region around the distal portion can be irrigated with the ejection of the liquid, supplied into the lumen of the injection needle, from the plurality of fine holes.

(2) In the ablation needle device according to the present invention, it is preferable that a pitch of the slit formed in the proximal portion of the injection needle be continuously or intermittently reduced in a direction toward the distal end.

In such an ablation needle device, the rigidity of the proximal portion of the injection needle can be continuously or intermittently reduced in the direction toward the distal end. Accordingly, the needle device can exhibit especially high operability in the introduction of the injection needle into the adrenal gland.

(3) In the ablation needle device according to the present invention, it is preferable that the distal portion of the injection needle have a length of 1 to 6 mm, the region of the proximal portion of the injection needle where the slit is formed have a length of 40 to 700 mm, the injection needle have an inside diameter of 0.25 to 2.8 mm, and the fine holes each have a diameter of 0.01 to 0.25 mm.

(4) It is preferable that the ablation needle device according to the present invention be an ablation needle device intended for a high-frequency ablation treatment in which adrenal tumor tissue around the distal portion of the injection needle is heated by supplying a high-frequency current to the distal portion,

the grip portion have an energization connector for supplying the high-frequency current to the distal portion of the injection needle,

the injection port be an injection port for a physiological saline solution, and irrigation with the physiological saline solution through the plurality of fine holes be performed by injecting the physiological saline solution into the lumen of the injection needle from the injection port.

When such an ablation needle device is included in a high-frequency ablation treatment system to be described below, a high-frequency ablation treatment of an adrenal tumor (a transvenous ablation treatment for primary aldosteronism) can be performed assuredly. Furthermore, during the high-frequency ablation treatment, irrigation can be performed with the physiological saline solution through the plurality of fine holes formed in the distal portion of the injection needle. Hence, biological tissue or thrombi can be prevented from adhering to the surface of the distal portion of the injection needle.

(5) In the ablation needle device according to (4) described above, it is preferable that the grip portion have a thermocouple connector for measuring a temperature of the distal portion of the injection needle.

(6) In the ablation needle device according to the present invention, it is preferable that the injection port be an injection port for ethanol, and a chemical ablation treatment of an adrenal tumor is performed by injecting the ethanol into the lumen of the injection needle from the injection port and ejecting the ethanol from the plurality of fine holes.

When such an ablation needle device is included in a chemical ablation treatment system to be described below, a chemical ablation treatment of an adrenal tumor (a transvenous ablation treatment for primary aldosteronism) can be performed assuredly.

(7) A high-frequency ablation treatment system for an adrenal tumor according to the present invention comprises the ablation needle device according to (4);

a high-frequency power supply device connected to the energization connector;

a counter-electrode plate connected to the high-frequency power supply device;

physiological-saline-solution-supplying means connected to the injection port; and

a guiding catheter for guiding the distal portion of the injection needle to the adrenal gland.

(8) A chemical ablation treatment system for an adrenal tumor according to the present invention comprises:

the ablation needle device according to (6);

ethanol-supplying means connected to the injection port; and

a guiding catheter for guiding the distal portion of the injection needle to the adrenal gland.

Advantageous Effects of Invention

With the ablation needle device according to the present invention, the transvenous ablation treatment, which is a novel treatment method for primary aldosteronism, can be performed assuredly.

The ablation needle device according to the present invention is applicable to both a high-frequency ablation treatment and a chemical ablation treatment.

With the high-frequency ablation treatment system according to the present invention, the high-frequency ablation treatment (a transvenous ablation treatment) of an adrenal tumor can be performed assuredly.

With the chemical ablation treatment system according to the present invention, the chemical ablation treatment (a transvenous ablation treatment) of an adrenal tumor can be performed assuredly.

DESCRIPTION OF EMBODIMENTS

First Embodiment

An ablation needle device100according to the present embodiment is an ablation needle device intended for a high-frequency ablation treatment in which adrenal tumor tissue around a distal portion of an injection needle is heated by supplying a high-frequency current to the distal portion.

The ablation needle device100according to the present embodiment illustrated inFIGS. 1 to 5A and 5Bis an ablation needle device intended for a high-frequency ablation treatment of an adrenal tumor with transvenous introduction of an injection needle into an adrenal gland, the ablation needle device100including a metal injection needle10that includes a pointed tubular distal portion11and a tubular proximal portion12whose lumen communicates with a lumen of the distal portion11and has substantially the same diameter as the lumen of the distal portion11; and a grip portion20attached to a proximal side of the injection needle10, wherein the proximal portion12of the injection needle10is given flexibility (bendability) in a distal region12A thereof by forming a helical slit14therein, and an outer surface of the proximal portion12is coated with coating resin16; wherein the distal end of the distal portion11of the injection needle10is closed, and a plurality of fine holes15communicating with the lumen of the distal portion11are formed in an outer surface of the distal portion11including the closed part13; wherein the grip portion20has an injection port25for supplying a physiological saline solution into the lumen of the injection needle10; and wherein the grip portion20is provided with an energization connector35to be connected to a high-frequency power supply device so that a high-frequency current is supplied to the distal portion11of the injection needle10, and to a thermocouple connector45connected to a temperature sensor (a thermocouple40) provided in the distal portion11of the injection needle10.

The ablation needle device100includes the injection needle10and the grip portion20. The injection needle10includes the distal portion11and the proximal portion12.

The length of the injection needle10is, for example, 400 to 2200 mm, preferably 600 to 1000 mm.

The outside diameter of the injection needle10(the distal portion11and the proximal portion12) is, for example, 0.55 to 3.0 mm, preferably 0.7 to 2.0 mm.

The inside diameter of the injection needle10(the distal portion11and the proximal portion12) is, for example, 0.25 to 2.8 mm, preferably 0.6 to 1.9 mm.

In the present embodiment in which the distal end of the proximal portion12is inserted in a proximal-end opening of the distal portion11, the inside diameter of the proximal portion12is slightly smaller than the inside diameter of the distal portion11. However, the two inside diameters are almost (substantially) the same.

As illustrated inFIGS. 2 to 4, the distal portion11of the injection needle10is made of a pointed metal tube, and the distal end thereof (a distal-end opening of a typical injection needle) is closed.

The plurality of fine holes15communicating with the lumen of the distal portion11are formed in the outer surface of the distal portion11including the closed part13.

As illustrated inFIGS. 2 and 3, a blade18is formed at the outer edge of the closed part13. The injection needle10can advance through the adrenal gland while tearing the tissue with the blade18. Therefore, the distal portion11of the injection needle10can easily reach a target adenoma (a tumor to be treated).

Examples of the material for the distal portion11include stainless steel, NiTi, β-titanium, platinum-iridium, and the like.

The length (denoted by L11inFIG. 2) of the distal portion11of the injection needle10is, for example, 1 to 6 mm, preferably 2.5 to 4.5 mm.

If the distal portion11is too short, the heat-generating area with respect to the target adenoma becomes too small. Accordingly, ablation nest(the region to be ablated) by such a distal portion becomes small, which may result in unsatisfactory effect of the treatment.

In contrast, if the distal portion11is too long, the followability of the injection needle with respect to the blood vessel may be deteriorated. Consequently, the injection needle may become unable to follow the venous blood vessel that meanders to the adrenal gland, being incapable of reaching the target adenoma.

The diameter of each of the fine holes15formed in the outer surface of the distal portion11is, for example, 0.01 to 0.25 mm, preferably 0.05 to 0.15 mm.

The density at which the fine holes15are formed is, for example, 4 to 100 holes/mm2, preferably 9 to 30 holes/mm2.

The proximal portion12of the injection needle10is a metal tube (a hypotube) in which the helical slit14is formed in the distal region12A thereof.

Exemplary materials for the proximal portion12include the same metals as those for the distal portion11.

The method of connecting the distal portion and the proximal portion of the injection needle is not specifically limited. In the present embodiment, the two are fixed to each other by inserting the distal end of the proximal portion12into the proximal-end opening of the distal portion11.

The helical slit14formed in the distal region12A of the proximal portion12is a through slit extending through the metal tube from the outer peripheral surface to the inner peripheral surface. The slit formed in the distal region of the proximal portion may be formed in such a manner as not to reach the inner peripheral surface.

Since the helical slit14is formed, the rigidity of the metal tube in that region is reduced to some extent, giving the metal tube flexibility (bendability). Hence, the injection needle10has excellent blood-vessel followability and can be easily made to follow the shape of the blood vessel reaching the adrenal gland.

In the distal region12A (the region in which the slit14is formed) of the proximal portion12, the pitch of the slit14is continuously reduced in a direction toward the distal end.

Thus, the rigidity of the distal region12A of the proximal portion12can be continuously (smoothly) reduced in the direction toward the distal end. Accordingly, the needle device can exhibit especially high operability in the introduction of the injection needle10into the adrenal gland.

In the present invention, the slit formed in the distal region of the proximal portion may be at regular pitches over the entirety thereof.

The length of the proximal portion12of the injection needle10is, for example, 394 to 2199 mm, preferably 594 to 999 mm.

The length of the distal region12A of the proximal portion12, i.e., the region in which the slit14is formed, is, for example, 40 to 700 mm, preferably 80 to 600 mm.

If the region in which the slit14is formed is too short, the change in the hardness becomes too large. Consequently, the insertion characteristics may be deteriorated.

In contrast, if the region in which the slit14is formed is too long, the torque transmission may be reduced.

The method of forming the slit14in the distal region12A is not specifically limited and may be laser machining, electric discharge machining, chemical etching, cutting, or the like.

The width of the slit14is, for example, 0.01 to 0.1 mm, preferably 0.02 to 0.04 mm.

The outer surface of the proximal portion12is coated with the insulating coating resin16.

Hence, a high-frequency current flows between the distal portion11of the injection needle10and a counter-electrode plate (a high-frequency current is supplied to the distal portion11of the injection needle10). Accordingly, the distal portion11serves as a distal-end electrode. Furthermore, since the slit14formed in the distal region12A of the proximal portion12is closed by the coating resin16, the injection needle10is assuredly made liquid-tight.

The film thickness of the coating resin16is, for example, 10 to 100 μm, preferably 20 to 40 μm.

The coating resin16is formed by shrinking a heat-shrinkable resin tube with the proximal portion12being inserted therein. An example of the heat-shrinkable resin tube forming the coating resin16may be polyether block amide copolymer resin (PEBAX, registered trademark).

When the ablation needle device100according to the present embodiment is included in a high-frequency ablation treatment system to be described below, a high-frequency ablation treatment of an adrenal tumor (a transvenous ablation treatment for primary aldosteronism) can be performed. Furthermore, since this ablation treatment is performed transvenously, a high-frequency ablation treatment of a tumor in the left adrenal gland, which has been difficult to perform in the known technique in which a high-frequency needle is stuck from the back, can be performed relatively easily.

Furthermore, since the helical slit14is formed in the distal region12A of the proximal portion12of the injection needle10, the rigidity in the distal region12A is reduced to some extent, whereby the injection needle10can be made flexible. Therefore, the injection needle10can be made to follow the shape of the blood vessel reaching the adrenal gland, and the distal portion11of the injection needle10can be made to reach a tumor site in the adrenal gland, without damaging the vascular wall.

Furthermore, when a physiological saline solution is injected from the injection port25, provided in the grip portion20, during the high-frequency ablation treatment, the physiological saline solution can be ejected for irrigation from the plurality of fine holes15formed in the distal portion11of the injection needle10. Thus, biological tissue or thrombi can be assuredly prevented from adhering to the surface of the distal portion11of the injection needle10.

Second Embodiment

An ablation needle device200according to the present embodiment illustrated inFIG. 6is an ablation needle device intended for a chemical ablation treatment of an adrenal tumor in which ethanol is injected into the lumen of an injection needle10from an injection port25and is thus ejected for irrigation from a plurality of fine holes15formed in a distal portion11of the injection needle10.

InFIG. 6, elements denoted by the same reference numerals as those used inFIG. 1are the same as respective elements included in the ablation needle device100according to the first embodiment. The ablation needle device200according to the present embodiment is an ablation needle device intended for a chemical ablation treatment. Therefore, the grip portion20included in the ablation needle device200is provided with neither the energization connector nor the thermocouple connector.

When the ablation needle device200according to the present embodiment is included in a chemical ablation treatment system to be described below (when ethanol-supplying means is connected to the injection port25), a chemical ablation treatment of an adrenal tumor (a transvenous ablation treatment) can be performed.

Furthermore, since the helical slit14is formed in the distal region12A of the proximal portion12of the injection needle10, the injection needle10can be made to follow the shape of the blood vessel reaching the adrenal gland. Consequently, the distal portion11of the injection needle10can be made to reach a tumor site in the adrenal gland, without damaging the vascular wall.

A high-frequency ablation treatment system600according to the present embodiment illustrated inFIG. 7includes the ablation needle device100according to the first embodiment, a high-frequency power supply device130connected to the energization connector35of the ablation needle device100, a counter-electrode plate (patient plate)150connected to the high-frequency power supply device130, physiological-saline-solution-supplying means120connected to the injection port25of the ablation needle device100, and a guiding catheter160for guiding the distal portion of the injection needle10to an adrenal gland AG of a patient P.

As illustrated inFIG. 7, the energization connector35of the ablation needle device100is connected to a needle-device-connecting connector131included in the high-frequency power supply device130. A counter-electrode-plate-connecting connector132included in the high-frequency power supply device130is connected to the counter-electrode plate150.

This enables a high-frequency current to flow between the distal portion of the injection needle10of the ablation needle device100and the counter-electrode plate150(a high-frequency ablation treatment of an adrenal tumor can be performed).

The physiological-saline-solution-supplying means120is connected to the injection port25of the grip portion20of the ablation needle device100.

Hence, during a high-frequency ablation treatment, a physiological saline solution can be injected from the physiological-saline-solution-supplying means120into the lumen of the injection needle10through the injection port25, and the physiological saline solution can be ejected for irrigation from the plurality of fine holes formed in the distal portion of the injection needle10.

The guiding catheter160included in the high-frequency ablation treatment system600is inserted in advance such that the distal end thereof is positioned in (near) the adrenal gland, in order to guide the distal portion of the injection needle10of the ablation needle device100to the adrenal gland AG of the patient P.

The shape of the guiding catheter160schematically illustrated inFIG. 7depends on whether it is intended for the right adrenal gland or the left adrenal gland, because the blood vessels reaching the respective adrenal glands have different shapes.

FIG. 9Aillustrates the shape of a distal portion of a guiding catheter160R for the right adrenal gland.FIG. 9Billustrates the shape of a distal portion of a guiding catheter160L for the left adrenal gland.

The guiding catheters160R and160L illustrated inFIGS. 9A and 9Beach have a plurality of curved parts.

When the distal region of the injection needle10is projecting from the distal-end opening of the guiding catheter160R or160L, the proximal end of the region of the injection needle10where the slit14is formed is desirably positioned further on the proximal side with respect to the proximal end of one of the curved parts of the guiding catheter that is at the most proximal side. Thus, the needle device can exhibit especially high operability.

The guiding catheter160R for the right adrenal gland that is illustrated inFIG. 9Ais inserted such that, as illustrated inFIG. 10A, the distal end thereof is positioned at (near) a right adrenal gland RAG through an inferior vena cava IVC and the right adrenal vein. The guiding catheter160L for the left adrenal gland that is illustrated inFIG. 9Bis inserted such that, as illustrated inFIG. 10B, the distal end thereof is positioned at (near) a left adrenal gland LAG through the inferior vena cava IVC, a left renal vein LRV, and the left adrenal vein.

InFIGS. 10A and 10B, RK denotes the right kidney, and LK denotes the left kidney.

The outside diameter of the guiding catheter160(160R,160L) is, for example, 1.0 to 4.0 mm, preferably 1.5 to 2.7 mm.

The inside diameter of the guiding catheter160is, for example, 0.6 to 3.1 mm, preferably 0.75 to 2.1 mm.

The length of the guiding catheter160is, for example, 350 to 2100 mm, preferably 550 to 950 mm.

The guiding catheter160(160R,160L) may be a catheter used for sampling blood from the adrenal vein (adrenal venous sampling).

With the high-frequency ablation treatment system600according to the present embodiment, a high-frequency ablation treatment (a low-invasive transvenous ablation treatment) of an adrenal tumor can be performed by causing a high-frequency current to flow between the distal portion of the injection needle10of the ablation needle device100and the counter-electrode plate150.

Furthermore, during the high-frequency ablation treatment, when the physiological saline solution supplied from the physiological-saline-solution-supplying means120is ejected for irrigation from the plurality of fine holes formed in the distal portion of the injection needle10of the ablation needle device100, biological tissue or thrombi can be assuredly prevented from adhering to the surface of the distal portion of the injection needle10.

A chemical ablation treatment system700according to an embodiment illustrated inFIG. 8includes the ablation needle device200according to the second embodiment, ethanol-supplying means220connected to the injection port25of the ablation needle device200, and a guiding catheter260for guiding the distal portion of the injection needle10to the adrenal gland AG of the patient P.

The ethanol-supplying means220is connected to the injection port25of the grip portion20of the ablation needle device200.

Hence, ethanol can be injected from the ethanol-supplying means220into the lumen of the injection needle10through the injection port25, and a chemical ablation treatment of an adrenal tumor can be performed while the ethanol is ejected from the plurality of fine holes formed in the distal portion of the injection needle10.

The guiding catheter260included in the chemical ablation treatment system700has the same configuration as the guiding catheter160(160R,160L) included in the high-frequency ablation treatment system600illustrated inFIGS. 7, 9(9A,9B), and10(10A,10B).

With the chemical ablation treatment system700according to the present embodiment, a chemical ablation treatment (a low-invasive transvenous ablation treatment) of an adrenal tumor can be performed by ejecting the ethanol supplied from the ethanol-supplying means220from the plurality of fine holes formed in the distal portion of the injection needle10of the ablation needle device100and by bringing the ethanol into contact with the tumor tissue.

REFERENCE SIGNS LIST

12A distal region of proximal portion

130high-frequency power supply device

600high-frequency ablation treatment system

700chemical ablation treatment system