1. Field of the Invention
The present invention relates to a medical treatment instrument, and more particularly, to a medical treatment instrument which is inserted into a body cavity through a treatment instrument channel of an endoscope to collect tissue or a cell at a predetermined portion of the body cavity.
2. Description of Related Art
Conventionally, as a treatment instrument which performs treatment of tissue or a cell at a predetermined portion of a body cavity, for example, a treatment instrument described in Japanese Unexamined Patent Application, First Publication No. 2008-5965 is known. In addition, in Japanese Unexamined Patent Application, First Publication No. 2000-201939, a treatment instrument which performs treatment of a submucosal tumor is disclosed. The treatment instrument described in Japanese Unexamined Patent Application, First Publication No. 2000-201939 includes a sheath, an operation motion transmission member which is disposed to be capable of advancing and retracting in its axial direction along the sheath to advance and retract by an operation from a hand side, and a pair of distal end treatment members disposed to be openable and closable in the shape of a beak at a distal end of the sheath to be opened and closed by the advancing and retracting movement of the operation motion transmission member. In the treatment instrument, distal end portions of the pair of distal end treatment members are formed in acute shapes to be sharp at the front. By the treatment instrument, puncture of a submucosal tumor and collection of a biopsy tissue can be performed in one operation.
In addition, as a method of collecting tissue of a submucosal tumor, aspiration biopsy which is performed by Fine-Needle Aspiration (FNA), for example, is known. During the aspiration biopsy, tissue is punctured with a biopsy needle, and then the tissue is aspirated by filling a negative pressure in the biopsy needle with a syringe, and so on.
According to a first aspect of the present invention, a medical treatment instrument includes: a tubular sheath; a needle formed in a tubular shape and inserted into the sheath such that the needle is capable of advancing and retracting; a stylet having a first outer diameter and inserted into the needle such that the stylet is capable of advancing and retracting; a housing portion which is elastically deformable at a distal end portion of the needle, the housing portion having a space formed in a tubular inside of the distal end portion of the needle; a small-diameter portion provided at a proximal end of the housing portion and having an inner diameter smaller than an inner diameter of the housing portion; a slit extending at least from a distal end of the housing portion to the small-diameter portion, the slit being configured to cause an outside of the needle to communicate with the space; and a large-diameter portion having a second outer diameter which is larger than the first outer diameter at a distal end portion of the stylet, the large-diameter portion being configured to, by the large-diameter portion being engaged with the small-diameter portion, cause the small-diameter portion and the housing portion to be elastically deformed to expand in a radial direction of the needle while a width of the slit expands.
According to a second aspect of the present invention, in the medical treatment instrument according to the first aspect, the first outer diameter may be smaller than the inner diameter of the small-diameter portion. The second outer diameter may be larger than the inner diameter of the small-diameter portion and is smaller than the inner diameter of the housing portion.
According to a third aspect of the present invention, in the medical treatment instrument according to the first aspect, the slit may include a plurality of slits which are formed at the housing portion.
According to a fourth aspect of the present invention, in the medical treatment instrument according to the first aspect, the large-diameter portion may be positioned closer to a distal end side than the small-diameter portion in an initial state, and the large-diameter portion may expand the small-diameter portion by the stylet being pulled toward a proximal end side with respect to the needle.
According to a fifth aspect of the present invention, in the medical treatment instrument according to the first aspect, when the large-diameter portion is disengaged from the small-diameter portion by the stylet being pulled toward proximal end side from a position at which the large-diameter portion is engaged with the small-diameter portion, the housing portion may be closed.
Hereinafter, a first embodiment of the present invention will be described with reference to
As shown in
The needle 10 is constituted with a metal such as stainless steel or a nickel-titanium alloy and can be elastically deformed. The needle 10 is formed in the tubular shape and has a lumen 11. Like a general puncturing needle, the needle 10 may be, for example, a 19-gauge needle (outer diameter of 1.1 mm, inner diameter of 0.78 mm). In addition, a needle which is narrower than the needle having the size above may also be used as the needle 10. A distal end of the needle 10 is formed in the shape of a curved surface so as to easily puncture tissue with the needle 10. In addition, the distal end of the needle 10 may also be formed in an acute shape.
A distal end portion 12 of the needle 10 can be elastically deformed. As shown in
The space 15 capable of accommodating tissue to be collected is formed in the housing portion 14. The inner diameter and the outer diameter of the housing portion 14 are substantially the same as the inner diameter and the outer diameter of the needle 10 which is closer to the proximal end side than the distal end portion 12, respectively. However, the inner diameter and the outer diameter of the housing portion 14 may respectively be set differently from the inner diameter and the outer diameter of the needle 10 which is closer to the proximal end side than the distal end portion 12. The length of the housing portion 14 in an axial direction of the needle 10 is properly set depending on an amount of tissue to be collected. The size of the space 15 is defined by the inner diameter of the housing portion 14 and the length of the housing portion 14 in the axial direction of the needle 10.
The small-diameter portion 16 is provided at the proximal end of the housing portion 14. The small-diameter portion 16 has a smaller inner diameter than other portions of the needle 10 including the housing portion 14. The small-diameter portion 16 may be formed by making a part of a proximal end side of the housing portion 14 in the needle 10 concave in a radial direction of the needle 10. In this case, the small-diameter portion 16 has a smaller outer diameter than other portions of the needle 10 including the housing portion 14. A proximal end of the small-diameter portion 16 continues to a straight tube portion of the needle 10. The straight tube portion of the needle 10 is formed in the shape of a tube with a fixed inner diameter and a fixed outer diameter.
The slit 18 is formed at the distal end portion 12, and extends from the distal end of the needle 10 (distal end of the housing portion 14) to the proximal end of the distal end portion 12. The slit 18 should extend at least from the distal end of the needle 10 to the proximal end of the small-diameter portion 16. In the embodiment, an example in which three slits 18 are formed is shown. However, the number of slits is not limited as long as there are one or more slits. When a plurality of slits 18 are formed, as in the embodiment shown in
As shown in
The stylet 30 has the predetermined outer diameter (first outer diameter), and is inserted into the needle 10 to be capable of advancing and retracting. The stylet 30 is constituted with metal such as stainless steel, and is formed in the shape of a round rod. The stylet 30 is inserted into the lumen 11 and the insertion passage 21, and is capable of advancing and retracting with respect to the needle 10. The outer diameter (first outer diameter) of the stylet 30 is smaller than the inner diameter of the small-diameter portion 16.
A distal end portion 32 of the stylet 30 has a large-diameter portion 34. The large-diameter portion 34 is formed in a substantially cylindrical shape, and has an outer diameter (second outer diameter) larger than the outer diameter (first outer diameter) of other portions of the stylet 30. The outer diameter (second outer diameter) of the large-diameter portion 34 is larger than the inner diameter of the small-diameter portion 16, and is smaller than the inner diameter of the housing portion 14.
A stylet operation part 36 is provided at a proximal end of the stylet 30. By advancing and retracting the stylet operation part 36, the stylet 30 can advance and retract with respect to the needle 10.
The sheath 40 is constituted with a resin material, and is formed in a tubular shape. In addition, the sheath 40 may be formed by a coil sheath around which a wire of a metal material such as stainless steel is tightly wound with no gaps formed therebetween. The needle 10 is inserted into a lumen of the sheath 40 to be capable of advancing and retracting with respect to the sheath 40. When the medical treatment instrument 1 is inserted into the channel 103, the distal end of the needle 10 is stored in the sheath 40. In this way, damage of the needle 10 or the channel 103 due to direct contact between the needle 10 and an inner surface of the channel 103 is prevented.
A sheath operation part 42 is provided at a proximal end of the sheath 40. By advancing and retracting the sheath operation part 42, the sheath 40 can advance and retract with respect to the channel 103 of the endoscope 100.
Next, an operation of the distal end portion 12 will be described.
In the embodiment, as shown in
By moving the large-diameter portion 34 engaged with the small-diameter portion 16 further toward the proximal end by operating the stylet operation part 36, the engagement between the large-diameter portion 34 and the small-diameter portion 16 is released, and the large-diameter portion 34 moves toward the proximal end side of the small-diameter portion 16. As the engagement between the large-diameter portion 34 and the small-diameter portion 16 is released, each of the three portions of the distal end portion 12 is elastically deformed to move to the inside in the radial direction of the needle 10 by an elastic force attempting to restore to the original shape of the needle 10, and the width of each of the slits 18 is restored to the original size. That is, the housing portion 14 and the small-diameter portion 16 are closed, and the space 15 is closed with respect to the outside of the needle 10. In addition, in the above example, although the operation of the distal end portion 12 when the large-diameter portion 34 is moved from the distal end side toward the proximal end side of the small-diameter portion 16 has been described, the distal end portion 12 performs the same operation when the large-diameter portion 34 is moved from the proximal end side toward the distal end side of the small-diameter portion 16.
Next, treatment using the medical treatment instrument 1 according to the embodiment will be described with reference to
First, an operator inserts the endoscope insertion part 101 of the endoscope 100 from a patient's mouth into the body cavity, and moves the distal end of the endoscope insertion part 101 up to a portion near a target portion T. The medical treatment instrument 1 is inserted into the channel 103, and the distal end of the medical treatment instrument 1 is moved up to the distal end of the endoscope insertion part 101. Here, the distal end of the needle 10 is stored in the sheath 40. In addition, in the treatment example, a case in which the large-diameter portion 34 of the stylet 30 is arranged at the distal end side of the small-diameter portion 16 of the needle 10 in the initial state will be described.
The operator operates the sheath operation part 42 to cause the sheath 40 to protrude from the distal end of the endoscope insertion part 101 while observing the target portion T with an imaging means provided at the distal end of the endoscope insertion part 101. Then, the operator advances the needle operation part 20 to cause the needle 10 to protrude from the distal end of the sheath 40, and punctures the target portion T by the needle 10.
When the target portion T is punctured by the needle 10, as shown in
Then, in this state, the operator operates the needle operation part 20 and sticks the needle 10 into the submucosal tumor ST as shown in
In addition, although it has been described above that the large-diameter portion 34 is arranged at the distal end side of the small-diameter portion 16 in the initial state, the large-diameter portion 34 may be arranged at the proximal end side of the small-diameter portion 16 in the initial state. In this case, the operation of moving the large-diameter portion 34 toward the proximal end side in the description above is substituted with an operation of moving the large-diameter portion 34 toward the distal end side.
In the medical treatment instrument 1 according to the embodiment, the slits 18 are provided at the distal end portion 12 of the needle 10, and the distal end portion 12 (the housing portion 14 and the small-diameter portion 16) can be elastically deformed to expand toward the outside in the radial direction. In this way, a sufficient amount of tissue can be collected even when the outer diameter of the needle 10 is narrow. In addition, in the medical treatment instrument 1 according to the embodiment, from the state in which the distal end portion 12 has expanded toward the outside in the radial direction, the distal end portion 12 is restored to the originally closed state by its elastic force. For this reason, even when collecting tissue of the submucosal tumor which is hard tissue, the distal end portion 12 can be restored to the originally closed state by its elastic force overcoming the hardness of the tissue, and the tissue can be reliably collected.
In addition, in the medical treatment instrument 1 according to the embodiment, a blade may be formed at a portion where the slit 18 of the distal end portion 12 of the needle 10 is formed. In this way, when the distal end portion 12 is closed, the tissue can be easily split and collected.
In the medical treatment instrument 1 according to the embodiment, the operator can recognize that the large-diameter portion 34 is engaged with the small-diameter portion 16 by the clicking sensation. In addition, by providing a known stopper mechanism, which stops the stylet 30 at a time when the stylet 30 has been operated by a predetermined amount, at the stylet operation part 36, the medical treatment instrument 1 may be constituted in a way that the operator can check that the large-diameter portion 34 is engaged with the small-diameter portion 16.
In the medical treatment instrument 1 according to the embodiment, the sheath 40 is not an essential constitution. The medical treatment instrument 1 may not include the sheath 40. In addition, instead of the sheath 40, a known sheath and the medical treatment instrument 1 may be used in combination.
Next, a second embodiment of the present invention will be described with reference to
As shown in
The straight tube portion 222 is disposed between the housing portion 214 and the stepped portion 224. The straight tube portion 222 has an inner diameter and an outer diameter which are respectively substantially the same as the inner diameter and the outer diameter of the housing portion 214 when the housing portion 214 is closed. The outer diameter of the straight tube portion 222 is smaller than an outer diameter of portions of the needle 210 other than the housing portion 214. The length of the straight tube portion 222 in the axial direction of the needle 210 is properly set depending on a length to which target tissue is punctured by the needle 210.
The stepped portion 224 has a shape which extends from the straight tube portion 222 while an outer diameter thereof expanding. The stepped portion 224 comes in contact with a protruding portion 244 of the sheath distal end member 242 to be described below. By the stepped portion 224 coming in contact with the protruding portion 244, the needle 210 is prevented from moving further toward the distal end side with respect to the sheath 240.
The sheath distal end member 242 is mounted at a distal end of the sheath 240. The sheath distal end member 242 is formed in a tubular shape having an inner diameter and an outer diameter which are respectively substantially the same as the inner diameter and the outer diameter of the sheath 240. A lumen of the sheath distal end member 242 communicates with a lumen of the sheath 240, and the needle 210 is inserted into the lumen of the sheath distal end member 242. The needle 210 can advance and retract with respect to the sheath 240 and the sheath distal end member 242. The protruding portion 244 which protrudes toward the inside in the radial direction of the sheath distal end member 242 is provided at the distal end of the sheath distal end member 242. At the distal end of the sheath distal end member 242, an opening 246 which communicates with the lumen of the sheath distal end member 242 is formed further toward the inside in the radial direction than the protruding portion 244. The diameter of the opening 246 is slightly larger than the outer diameter of the straight tube portion 222, and is smaller than the outer diameter of the stepped portion 224. Thus, although the straight tube portion 222 can be inserted into the opening 246, the stepped portion 224 cannot be inserted into the opening 246 due to coming in contact with the protruding portion 244. By being elastically deformed in the closed state, the housing portion 214 can be inserted into the opening 246. That is, by the housing portion 214 being inserted into the opening 246, an outer surface of the housing portion 214 is pressed by the protruding portion 244, and the housing portion 214 is elastically deformed in the closed state.
Next, treatment using the medical treatment instrument 201 according to the embodiment will be described using
First, as in the first embodiment, the operator uses the endoscope 100 to send the distal end of the medical treatment instrument 201 to a portion near the target portion T. The operator advances the needle operation part 20 to cause the needle 210 to protrude from the distal end of the sheath distal end member 242. Here, as shown in
Next, the operator advances the needle 210 with respect to the sheath distal end member 242. In this way, when the housing portion 214 passes the protruding portion 244 and moves toward the distal end side, as shown in
In the medical treatment instrument 201 according to the embodiment, the slits 218 are provided at the housing portion 214 of the needle 210, the housing portion 214 is formed by plastic deformation in the shape that expands toward the outside in the radial direction, and the housing portion 214 can be closed by elastic deformation. Accordingly, after tissue is punctured by the needle 210 while the housing portion 214 is closed, the housing portion 214 is expanded, and thus a sufficient amount of tissue can be collected even when the outer diameter of the needle 210 is narrow. In addition, in the medical treatment instrument 201 according to the embodiment, the housing portion 214 is closed due to the outer surface of the housing portion 214 being pressed by the protruding portion 244 of the sheath distal end member 242. Accordingly, even when collecting tissue of a submucosal tumor which is hard tissue, the housing portion 214 can be closed with a force overcoming the hardness of the tissue, and the tissue can be reliably collected.
Although preferred embodiments of the present invention have been described above, the present invention is not limited to the embodiments. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit and scope of the present invention. The present invention is not limited by the description above, and is only limited by the scope of the appended claims.
Number | Date | Country | Kind |
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2014-166318 | Aug 2014 | JP | national |
This application is a continuation application based on PCT Patent Application No. PCT/JP2015/063098, filed May 1, 2015, whose priority is claimed on Japanese Patent Application No. 2014-166318, filed Aug. 19, 2014. The contents of both the PCT Patent Application and the Japanese Patent Application are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/JP2015/063098 | May 2015 | US |
Child | 15215035 | US |