Patent Description:
When a medicine is administered to a thin tissue in a living body such as a gastrointestinal mucous membrane, a posterior eye segment, or a mucous membrane of a nose using a common injection needle, an inclined blade surface may penetrate the tissue to cause a leakage of the liquid medicine to the outside of the tissue, or the injection needle may penetrate through the thin tissue, because the tissue is as thin as <NUM> or less. Therefore, there is a problem that a sufficient amount of liquid medicine cannot be reliably administered to the target tissue.

In order to address such a problem, <CIT> discloses a method of administering a medicine into a gastrointestinal mucous membrane using a puncture needle in which the medicine is applied to the tip of a microneedle.

However, the technology disclosed in <CIT> has a problem that, due to the amount of the medicine applied to the puncture needle being small, a sufficient amount of the medicine cannot be efficiently administered.

In view of this, an object of an embodiment is to provide a medical puncture needle capable of reliably administering a sufficient amount of a liquid medicine to a thin tissue.

In order to solve this problem, the present invention provides a medical puncture needle according to independent claim <NUM>. The dependent claims relate to advantageous embodiments.

According to the medical puncture needle of the above aspect, it is possible to efficiently administer a large amount of liquid medicine to a thin tissue.

Preferred embodiments of the present invention will now be described in detail with reference to the drawings.

As illustrated in <FIG>, a medical puncture needle <NUM> according to the present embodiment includes a cylindrical main body <NUM> having a through hole <NUM> formed therein, a blade surface <NUM> provided at a needle tip 14a of the main body <NUM>, and a circular blade edge <NUM> formed at a tip of the blade surface <NUM>.

The main body <NUM> is formed in a long cylindrical shape and is made of, for example, a metal material such as stainless steel. The diameter (outer diameter) of the main body <NUM> can be set to, for example, about <NUM> (about <NUM>).

The through hole <NUM> extends in the axial direction along a central axis C of the main body <NUM>. The through hole <NUM> is formed as a cavity having a circular cross section, and is formed to penetrate from a proximal end 14b of the main body <NUM> to the needle tip 14a. When the diameter of the main body <NUM> is set to, for example, <NUM> (about <NUM>), the inner diameter of the through hole <NUM> can be set to, for example, about <NUM>. An opening part 12a at the tip of the through hole <NUM> is provided inside the circular blade edge <NUM>. That is, the opening part 12a of the through hole <NUM> is formed along a plane perpendicular to the central axis C of the medical puncture needle <NUM>.

A liquid medicine permeation portion <NUM> is formed on an inner peripheral surface 14c of the through hole <NUM> near the needle tip 14a. The liquid medicine permeation portion <NUM> of the present embodiment has a liquid medicine passage groove <NUM> extending in the direction of the central axis C. The liquid medicine passage groove <NUM> serves as a flow path for guiding the liquid medicine to the needle tip 14a when the through hole <NUM> is closed by coring on a tissue <NUM> (see <FIG>) due to insertion of the medical puncture needle <NUM> into the tissue <NUM>. The liquid medicine passage groove <NUM> is formed as a groove-shaped recess that is recessed outward with respect to the inner peripheral surface 14c, and linearly extends in the direction of the central axis C. A tip part 20a of the liquid medicine passage groove <NUM> is positioned in the vicinity of the tip of the through hole <NUM>.

In addition, the liquid medicine passage groove <NUM> has a width and a depth capable of inhibiting entry of the tissue <NUM> during coring. When the diameter (outer diameter) of the main body <NUM> is set to, for example, <NUM> (about <NUM>) to <NUM> (about <NUM>), the width (dimension in the circumferential direction) of the liquid medicine passage groove <NUM> can be set to, for example, about <NUM> to <NUM>, and the depth (dimension in the radial direction) of the liquid medicine passage groove <NUM> can be set to about <NUM> to <NUM>.

In addition, when the diameter (outer diameter) of the main body <NUM> is set to, for example, <NUM> (about <NUM>) to <NUM> (about <NUM>), the width (dimension in the circumferential direction) of the liquid medicine passage groove <NUM> can be set to, for example, about <NUM> to <NUM>, and the depth (dimension in the radial direction) of the liquid medicine passage groove <NUM> can be set to about <NUM> to <NUM>. when the liquid medicine is administered to a site where coring is likely to occur or when the liquid medicine has high viscosity, it is preferable that the diameter (outer diameter) of the main body <NUM> is large, the width of the liquid medicine passage groove <NUM> is large, and the depth of the liquid medicine passage groove <NUM> is small.

Further, the position of a proximal end 20b of the liquid medicine passage groove <NUM> illustrated in <FIG> extends to a position where the tissue <NUM> (see <FIG>) of the living body cannot enter. The proximal end 20b of the liquid medicine passage groove <NUM> is preferably located, for example, at a position <NUM> or more away from the opening part 12a toward the proximal end side.

A plurality of the liquid medicine passage grooves <NUM> may be provided in the inner peripheral surface 14c of the through hole <NUM> in the circumferential direction. In a case where two liquid medicine passage grooves <NUM> are provided, the liquid medicine passage grooves <NUM> are arranged at an angle of <NUM>° in the circumferential direction. In addition, three, four, or more liquid medicine passage grooves <NUM> may be provided. In a case where the plurality of liquid medicine passage grooves <NUM> is provided, it is preferable to arrange the liquid medicine passage grooves evenly in the circumferential direction, and the plurality of liquid medicine passage grooves can be equally spaced in the circumferential direction.

As illustrated in <FIG>, the blade surface <NUM> is formed as an inclined curved surface obtained by obliquely cutting the needle tip 14a of the cylindrical main body <NUM> from the outer peripheral side toward the center. As illustrated in <FIG>, the cross section of the main body <NUM> at the portion where the blade surface <NUM> is formed is tapered so that the thickness is decreased toward the tip. The angle (inclination angle) between the blade surface <NUM> and the central axis C (see <FIG>) of the main body <NUM> can be set to, for example, about <NUM>° to <NUM>°.

The blade edge <NUM> is sharply formed at a portion where the blade surface <NUM> and the inner peripheral surface 14c of the through hole <NUM> are in contact with each other, and can puncture the tissue <NUM> of the living body. The blade edge <NUM> is formed in an annular shape along a plane perpendicular to the central axis C of the main body <NUM>. With this configuration, a load is distributed to the entire region of the blade edge <NUM> during puncturing. Therefore, the blade edge <NUM> is difficult to penetrate the tissue <NUM>, so that the blade edge <NUM> easily punctures the tissue <NUM> shallowly.

The medical puncture needle <NUM> described above is used in such a manner that the main body <NUM> is inserted into the thin layered tissue <NUM> in a direction perpendicular to the tissue <NUM> (thickness direction of the tissue <NUM>) as illustrated in <FIG>. Examples of the thin layered tissue <NUM> include intestinal mucosa, posterior eye segment, and olfactory mucosa, and the thickness of the tissue <NUM> is <NUM> or less. When the medical puncture needle <NUM> is inserted in the manner described above, the entire region of the blade edge <NUM> is aligned in the layer direction of the thin tissue <NUM>, so that the entire region of the opening part 12a of the through hole <NUM> stays in the tissue <NUM>. With the tissue <NUM> being punctured by the blade edge <NUM>, a part of the tissue <NUM> enters the inside of the through hole <NUM> by the coring. Therefore, most of the through hole <NUM> is closed by the tissue <NUM>. It is to be noted, however, that the tissue <NUM> cannot enter the liquid medicine passage groove <NUM>, because the liquid medicine passage groove <NUM> has a fine groove shape. Therefore, the liquid medicine passage groove <NUM> forms a flow path through which the liquid medicine can pass.

The liquid medicine is guided to the vicinity of the needle tip 14a of the medical puncture needle <NUM> through the liquid medicine passage groove <NUM>, and is injected into the tissue <NUM> from the vicinity of the blade edge <NUM>. As a result, the medical puncture needle <NUM> can efficiently administer a large amount of liquid medicine to the extremely thin tissue <NUM>.

As illustrated in <FIG>, in a medical puncture needle <NUM> of a comparative example, a blade surface <NUM> has a plane inclined with respect to the axial direction, and an opening part 92a of a through hole <NUM> of a needle tube <NUM> is exposed to the plane inclined in the axial direction. The opening part 92a of the through hole <NUM> is elongated along the axial direction of the medical puncture needle <NUM>. Therefore, when the medical puncture needle <NUM> is inserted, a part of the opening part 92a of the through hole <NUM> on the proximal end side protrudes from the thin tissue <NUM>, and this causes a leakage of the liquid medicine.

In addition, as illustrated in <FIG>, when the medical puncture needle <NUM> of the comparative example is deeply inserted, the opening part 92a of the through hole <NUM> penetrates the tissue <NUM> to cause a leakage of the liquid medicine. Therefore, the medical puncture needle <NUM> of the comparative example cannot efficiently administer the liquid medicine to the thin tissue <NUM>.

On the other hand, in the medical puncture needle <NUM> according to the present embodiment, the opening part 12a of the through hole <NUM> is formed inside the blade edge <NUM> perpendicular to the axial direction of the medical puncture needle <NUM>, and thus is short in the axial direction. Therefore, even when the very thin tissue <NUM> is punctured, the opening part 12a does not penetrate the tissue <NUM>, and the liquid medicine can be injected into the tissue <NUM> without leakage.

The medical puncture needle <NUM> described above can be manufactured in such a manner that, as illustrated in <FIG>, a metal tube <NUM> constituting the main body <NUM> is prepared, and the outer peripheral portion of the needle tip 14a of the main body <NUM> is electrolytically polished in a tapered shape to form the blade surface <NUM> and the blade edge <NUM>. In addition, the liquid medicine passage groove <NUM> can be formed by performing various types of processing, for example, machining (cutting or pressing), on the inner peripheral wall of the main body <NUM>.

The liquid medicine passage groove <NUM> of the medical puncture needle <NUM> is formed using plating. The case where the liquid medicine passage groove <NUM> of the medical puncture needle <NUM> is formed by plating will be described below.

As illustrated in <FIG>, first, the metal tube <NUM> is formed as a material of the medical puncture needle <NUM>. Next, a mask <NUM> made of, for example, a resin material is formed on a part of an inner surface 22a of the metal tube <NUM> by coating. The mask <NUM> is formed in the same planar shape as the liquid medicine passage groove <NUM>. Prior to the formation of the mask <NUM>, a seed layer serving as a base of the plating film may be formed.

Next, as illustrated in <FIG>, a metal layer <NUM> is formed inside the metal tube <NUM> by a method such as electrolytic plating or electroless plating. The metal layer <NUM> grows with the inner surface 22a of a portion not covered with the mask <NUM> as a base. The inner surface 22a of the portion not covered with the mask <NUM> is covered with the metal layer <NUM>. The metal layer <NUM> is made of, for example, metal such as Ni/Cr alloy, Cu/Cr alloy, Ni, Ni base alloy, Fe, Fe base alloy, Co, Co base alloy, Ag, Ag base alloy, Cu, Cu base alloy, Au, and Au base alloy.

Thereafter, the mask <NUM> is removed as illustrated in <FIG>. The mask <NUM> can be removed using a solvent, or the like. Due to the removal of the mask <NUM>, the liquid medicine passage groove <NUM> having a recessed groove is formed in the metal tube <NUM>. Next, the A-A portion in <FIG> is cut. Thus, two main bodies <NUM> having the cut portions of the metal tube <NUM> as tips are obtained.

Next, as illustrated in <FIG>, the blade surface <NUM> and the blade edge <NUM> are formed by performing electrolytic polishing obliquely along the outer periphery of the tip of the main body <NUM>. Through the above steps, the medical puncture needle <NUM> according to the present embodiment is completed.

The medical puncture needle <NUM> according to the present embodiment has the following effects.

The medical puncture needle <NUM> according to the present embodiment includes: the cylindrical main body <NUM> having the through hole <NUM> formed therein; the annular blade surface <NUM> cut into a tapered shape so that the thickness of the main body <NUM> reduces toward the needle tip 14a of the main body <NUM>; and the circular blade edge <NUM> formed at the tip of the blade surface <NUM> so as to extend along a plane orthogonal to the central axis C of the main body <NUM>.

According to the above configuration, when the medical puncture needle <NUM> is inserted into the thin tissue <NUM> in the direction perpendicular to the tissue <NUM>, the through hole <NUM> does not penetrate the tissue <NUM>, so that a large amount of liquid medicine can be efficiently injected into the tissue <NUM> without causing leakage of the liquid medicine.

In the medical puncture needle <NUM> described above, the liquid medicine permeation portion <NUM> having an uneven structure may be further formed in the inner peripheral surface 14c of the through hole <NUM> in the vicinity of the blade edge <NUM>.

When the medical puncture needle <NUM> is perpendicularly inserted into the tissue <NUM>, the through hole <NUM> may be closed by the tissue <NUM> due to coring. Even in such a case, it is possible to allow the liquid medicine to flow toward the blade edge <NUM> through the liquid medicine permeation portion <NUM>, whereby a sufficient amount of liquid medicine can be injected into the tissue <NUM>.

In the medical puncture needle <NUM> described above, the liquid medicine permeation portion <NUM> may include the liquid medicine passage groove <NUM> having a groove-shaped recess extending in the axial direction. Accordingly, even when the through hole <NUM> is closed by coring, it is possible to allow the liquid medicine to flow toward the blade edge <NUM> through the liquid medicine passage groove <NUM>.

In the medical puncture needle <NUM> described above, a plurality of the liquid medicine passage grooves <NUM> may be provided in the inner peripheral surface 14c of the through hole <NUM>. With this configuration, even when coring occurs, a sufficient amount of the liquid medicine can be injected into the tissue <NUM>.

As illustrated in <FIG>, a medical puncture needle 10A according to the present embodiment is different from the medical puncture needle <NUM> in <FIG> in the shape of a blade surface <NUM> formed at a needle tip 14a of a cylindrical main body <NUM>. Note that the components of the medical puncture needle 10A similar to the components of the medical puncture needle <NUM> in <FIG> are denoted by the same reference numerals, and the detailed description thereof will be omitted.

As illustrated in <FIG>, in the medical puncture needle 10A, the blade surface <NUM> includes an outer blade surface 28a obtained by obliquely cutting the main body <NUM> from the outer peripheral side, and an inner blade surface 28b obtained by obliquely cutting the main body <NUM> from the inner peripheral side. The outer blade surface 28a and the inner blade surface 28b have annular curved surfaces, and a sharp blade edge <NUM> is formed at a tip portion where the outer blade surface 28a and the inner blade surface 28b meet. The outer blade surface 28a and the inner blade surface 28b can be formed by electrolytic polishing.

As illustrated in <FIG>, the blade edge <NUM> is formed in an annular shape along a plane perpendicular to the central axis C of the main body <NUM>. The blade edge <NUM> in the present embodiment is wider than the through hole <NUM> of the main body <NUM>, and has a larger diameter than the blade edge <NUM> in <FIG>. According to the medical puncture needle 10A of the present embodiment, a load applied during puncture of the tissue <NUM> is distributed to the blade edge <NUM> in a wider area, whereby the liquid medicine easily flows out from the gap between the blade edge <NUM> and the tissue <NUM>.

As described above, in the medical puncture needle 10A according to the present embodiment, the blade surface <NUM> is formed on both the inner peripheral side and the outer peripheral side of the main body <NUM>. As a result, even in a case where the coring occurs, the load applied during puncture of the tissue <NUM> is distributed to the blade edge <NUM> in a wider area, so that the liquid medicine easily flows out from the gap between the blade edge <NUM> and the tissue <NUM>.

As illustrated in <FIG>, a medical puncture needle 10B according to the present embodiment is different from the medical puncture needle <NUM> in <FIG> in the shape of a blade surface <NUM> formed at a needle tip 14a of a cylindrical main body <NUM>. Note that the components of the medical puncture needle 10B similar to the components of the medical puncture needle <NUM> in <FIG> are denoted by the same reference numerals, and the detailed description thereof will be omitted.

As illustrated in <FIG>, in the medical puncture needle 10B, the blade surface <NUM> is formed by cutting the main body <NUM> in a tapered shape from the inner peripheral side. The blade surface <NUM> has an annular curved surface obliquely cut along the circumferential direction of the main body <NUM>. A sharp blade edge <NUM> is formed on a side where the outer peripheral surface of the main body <NUM> and the blade surface <NUM> meet. The blade edge <NUM> in the present embodiment is wider than the through hole <NUM> of the main body <NUM>, and has a diameter equal to the diameter of the main body <NUM>.

As described above, in the medical puncture needle 10B according to the present embodiment, the blade surface <NUM> is formed only on the inner peripheral side of the main body <NUM>. Thus, the blade edge <NUM> widens to have a diameter substantially equal to the diameter of the main body <NUM>. As a result, even in a case where the coring occurs when the medical puncture needle 10B is inserted into the tissue <NUM>, the load applied during insertion into the tissue <NUM> is distributed to the blade edge <NUM> in a wider area, so that the liquid medicine easily flows out from the gap between the blade edge <NUM> and the tissue <NUM>. As a result, the medical puncture needle 10B can inject a large amount of liquid medicine into the tissue <NUM>.

As illustrated in <FIG>, a medical puncture needle 10C according to the present embodiment is different from the medical puncture needle <NUM> in <FIG> in a liquid medicine permeation portion 15A formed in an inner peripheral surface 14c of a through hole <NUM> of a main body <NUM>. Note that the components of the medical puncture needle 10C similar to the components of the medical puncture needle <NUM> in <FIG> are denoted by the same reference numerals, and the detailed description thereof will be omitted.

In the medical puncture needle 10C according to the present embodiment, the liquid medicine permeation portion 15A having an uneven structure is formed in the inner peripheral surface 14c of the through hole <NUM>. The liquid medicine permeation portion 15A is formed by a plurality of liquid medicine passage grooves <NUM> arranged in a matrix. The liquid medicine passage grooves <NUM> can be formed by changing the pattern of the mask <NUM> in the step of forming the liquid medicine passage groove <NUM> by plating described with reference to <FIG>.

According to the medical puncture needle 10C of the present embodiment, even if coring occurs during puncture of the tissue <NUM>, it is possible to allow the liquid medicine to flow toward the needle tip 14a of the main body <NUM> through the liquid medicine permeation portion 15A. As a result, the medical puncture needle 10C can inject a large amount of liquid medicine into the tissue <NUM>.

Note that the structure of the liquid medicine permeation portion 15A of the present embodiment is not limited to the liquid medicine passage grooves <NUM> in a matrix, and can be replaced with various uneven structures such as protrusions that can generate a gap between the tissue <NUM> and the inner peripheral surface 14c of the through hole <NUM> when coring occurs.

As illustrated in <FIG>, a medical puncture needle 10D according to the present embodiment is different from the medical puncture needle <NUM> in <FIG> in a liquid medicine permeation portion 15B formed in an inner peripheral surface 14c of a through hole <NUM> of a main body <NUM>. Note that the components of the medical puncture needle 10D similar to the components of the medical puncture needle <NUM> in <FIG> are denoted by the same reference numerals, and the detailed description thereof will be omitted.

The medical puncture needle 10D according to the present embodiment has the liquid medicine permeation portion 15B which is formed in the inner peripheral surface 14c of the through hole <NUM> and which has a liquid medicine passage groove <NUM> extending to a proximal end 14b of the medical puncture needle 10D. The medical puncture needle 10D according to the present embodiment is manufactured as follows. First, a core material (not illustrated) having the same outer peripheral surface shape as the shape of the inner peripheral surface 14c of the through hole <NUM> and the liquid medicine permeation portion 15B is prepared.

The core material is formed with a linear protrusion extending in the axial direction in a portion corresponding to the liquid medicine passage groove <NUM>. Next, the core material is immersed in a plating solution (containing, for example, ions of Ni/Cr, Cu/Cr, Ni, Fe, Co, Ag, Cu, Au, etc.), and an electroformed body (for example, an electroformed body of Ni/Cr, Cu/Cr, Ni, Fe, Co, Ag, Cu, Au, etc.) is formed on the outer peripheral surface of the core material by plating. An electrolytic plating method is preferably used for forming the electroformed body by plating, but an electroless plating method may be partly used in combination during the process. Thereafter, the core material is removed from the electroformed body from the proximal end side to obtain the main body <NUM> constituted by a tubular electroformed body. The liquid medicine passage groove <NUM> is formed in the inner peripheral surface 14c of the main body <NUM>. Then, the blade surface <NUM> and the blade edge <NUM> are formed by performing electrolytic polishing obliquely along the outer periphery of the tip of the main body <NUM>. Through the above steps, the medical puncture needle 10D according to the present embodiment is completed.

The medical puncture needles in the second embodiment and the third embodiment described above can also be manufactured in the same manner.

Claim 1:
A medical puncture needle (<NUM>, 10A-D, <NUM>) comprising:
a main body (<NUM>) having a cylindrical shape and having inside a through hole (<NUM>, <NUM>);
a blade surface (<NUM>, <NUM>, 28a-b, <NUM>, <NUM>) that has an annular shape and that is cut into a tapered shape so that a thickness of the main body (<NUM>) reduces toward a tip part (20a) of the main body (<NUM>); and
a blade edge (<NUM>, <NUM>, <NUM>) that has an annular shape, the blade edge (<NUM>, <NUM>, <NUM>) being formed at a tip of the blade surface (<NUM>, <NUM>, 28a-b, <NUM>, <NUM>) so as to extend along a plane orthogonal to a central axis (C) of the main body (<NUM>),
wherein
the medical puncture needle (<NUM>, 10A-D, <NUM>) is configured for administering a liquid medicine into a tissue (<NUM>) of a living body,
the blade edge (<NUM>, <NUM>, <NUM>) is sharp, and
the diameter of the main body (<NUM>) is <NUM> to <NUM>,
characterized in that
the medical puncture needle (<NUM>, 10A-D, <NUM>) further comprises:
a liquid medicine permeation portion (<NUM>, 15A-B) formed on an inner peripheral surface (14c) of the through hole (<NUM>, <NUM>) near the blade edge (<NUM>, <NUM>, <NUM>), the liquid medicine permeation portion (<NUM>, 15A-B) guiding the liquid medicine to the blade edge (<NUM>, <NUM>, <NUM>) when the through hole (<NUM>, <NUM>) is closed by the tissue (<NUM>),
wherein
the liquid medicine permeation portion (<NUM>, 15A-B) comprises a liquid medicine passage groove (<NUM>, <NUM>) having a groove-shaped recess extending in an axial direction, or a protrusion generating a gap between the tissue (<NUM>) and the inner peripheral surface (14c),
the liquid medicine passage groove (<NUM>, <NUM>) has a width and a depth inhibiting entry of the tissue (<NUM>),
a proximal end of the liquid medicine passage groove (<NUM>, <NUM>) extends to a position where the tissue (<NUM>) does not enter, and
the liquid medicine passage groove (<NUM>, <NUM>) is formed using plating.