JP6058267B2 - Medical knife - Google Patents

Description

  The present invention relates to a medical knife suitable for incising a living tissue of an eyeball in ophthalmic surgery such as cataract surgery.

  For example, in cataract surgery performed under a microscope, the cornea of the eyeball has a predetermined centering on a crystalline lens with respect to the main port, other than the main port (incision) mainly used when inserting an intraocular lens. A side port (incision) may be formed at a position having a circumferential angle. Various instruments are inserted into and removed from such a side port, and viscoelastic substances are injected from the side port to replace the anterior aqueous humor, or an eyelid is moved by inserting an insulator into the side port. It can be held or the intraocular pressure can be increased with the perfusate from the side port at the end of the operation to check for leaks from the wound. About such a side port, if it is too large, it may cause a decrease in intraocular pressure or it may be difficult to heal the wound.

  When the side port is formed in the cornea of the eyeball, the shape of the side port connecting the outer incision line formed on the outer peripheral surface of the cornea and the inner incision line formed on the inner peripheral surface of the cornea Since the outer incision line on the outer peripheral surface becomes wider when it is formed into a trapezoidal shape that gradually narrows from the outer incision line toward the inner incision line on the inner peripheral surface, various instruments can be inserted and removed at the side port. When operating, the contact of various instruments with respect to the side port is reduced, and the insertion and removal and the operation are facilitated smoothly, which is preferable in terms of the operability of various instruments.

  For example, when the side port is formed by a conventionally known straight knife or MVR knife, there is room for improvement in forming the side port into a preferable shape because of the shape of the knife.

  FIG. 2B of Patent Document 1 below discloses a medical knife similar to the medical knife shown in FIG. 6C of the present application. In this medical knife, the blade along the cutting edge 10 extends from the tip 12 to the terminal 19 and intersects with the tip 12 on both sides in the width direction Y intersecting the thickness direction at the front portion 7 of the blade 6. A surface 9 is formed. The blade edge 10 on both sides in the width direction is partitioned by an intermediate portion 20 that bulges outward between the tip portion 12 and the end portion 19, and a tip side blade edge portion 21 that connects the tip portion 12 and the intermediate portion 20, A proximal edge edge 22 connecting the portion 20 and the terminal end 19. The blade surface 9 is partitioned from the intermediate boundary edge 23 passing through the intermediate portion 20 into a portion having the distal end side blade edge portion 21 and a portion having the proximal end side blade edge portion 22. The widthwise interval between the two blade edges 10 gradually increases from the tip 12 to the terminal 19, and the opening angle θ21 formed by the two distal-side blade edges 21 is the opening angle formed by the two proximal-side blade edges 22. It is set larger than θ22.

JP 2005-334054 A

  In the medical knife of the form shown in FIG. 6 (c), it is easier to insert into the cornea if the opening angle θ22 formed by the two proximal end blade edges 22 is somewhat small, while the two distal edge blade edges 21 are not. If the opening angle θ21 formed between each other is too small, there is a risk of inadvertent insertion or damage to the lens capsule at the beginning of insertion into the cornea. This is important in making it easy to form a side port (incision) into a trapezoidal shape so as not to insert it carelessly at the beginning.

  According to the present invention, even if the opening angle θ22 is set to be small to some extent and the insertion into the cornea is facilitated, the opening angle θ21 can be set large so that the insertion into the cornea is not inadvertently inserted. It is an object of the present invention to provide a medical knife that is easy to form in the trapezoidal shape of the side port formed in the cornea of the eyeball by improving the structure.

The present invention will be described with reference to the drawings of the following embodiments (the first embodiment shown in FIGS. 1 to 3 and the second embodiment shown in FIGS. 4 to 5).
The medical knife according to the invention of claim 1 is configured as shown in the following (a) to (h) .

(A) A blade portion (6) having both front and back portions ( 7, 8) in the thickness direction (Z) of the blade plate (4) is provided. On both sides of the width direction (Y) intersecting the thickness direction (Z) at the front portion (7) of the front and back portions (7, 8) of the blade portion (6), the tip portions (12) intersect each other. A blade surface (9) is formed along the cutting edge (10) extending from the tip (12) to the terminal end (19). The cutting edge (10) on both sides in the width direction is partitioned by the intermediate part (20) between the tip part (12) and the terminal part (19), and connects the tip part (12) and the intermediate part (20). It has a front end side blade edge part (21) and a proximal end side blade edge part (22) connecting the intermediate part (20) and the terminal part (19). The line segment part (27) connecting the intermediate parts (20) on both sides in the width direction has a top end part (13) whose opposite sides (11) cross each other with respect to the base end side blade edge part (22), and the front end side blade. The top end portion (13) between the tip end portion ( 12) and the top end portion (13) with respect to the tip side boundary edge (14) connecting the tip end portions (12) intersecting with each other. In the vicinity with respect to the crossing portion (27a) .

In the medical knife of the form shown in FIG. 6C, the line segment portion 27 that connects the intermediate portions 20 on both sides in the width direction has the opposite sides 11 with respect to both the distal end side blade edge portions 21 and both proximal end side blade edge portions 22. With respect to the extension line 37 of the distal end side boundary edge 14 connecting the apex portion 13 intersecting with each other and the apex portion 12 where both the distal end side blade edges 21 intersect with each other, the intersecting portion 27a is closer to the proximal end than the apex portion 13. Crossed. Further, the intermediate boundary edge 23 that divides the blade surface 9 intersects at the intersecting portion 23a on the base end side from the top end portion 13 and the intersecting portion 27a. However, as shown in FIGS. 6 (a) and 6 (b), in the configuration of (a) above, the line segment portion (27) connecting the intermediate portions (20) to each other has a top end portion (13) and a pointed end portion ( 12) and the tip-side boundary edge (14) connecting between the tip end portion (12) and the apex end portion (13) in the vicinity of the apex end portion (13) by the intersection (27a) . When the medical knife according to the above configuration (A) is compared with the medical knife shown in FIG. 6C, the opening angle (θ22) formed by the two proximal end blade edges (22) is determined. Even if the same value is set, the opening angle (θ21) formed by the two blade edges (21) with each other is more easily set to a larger value in the medical knife according to the configuration (A). Thus, since it becomes easy to set the opening angle (θ21) formed by the two tip side blade edges (21) to each other, when the side port (36) is formed on the cornea (35) of the eyeball (33), the blade Providing a medical knife with excellent operability by easily forming the side port (36) into a trapezoidal shape without inadvertently inserting the part (6) into the cornea (35) at the beginning. can do.

(B) The widthwise interval between the blade edges (10) gradually increases from the tip (12) toward the terminal portion (19), the intermediate portion (20) bulges outward, and the both edge edges The opening angle (θ21) formed by the portions (21) is set to be larger than the opening angle (θ22) formed by the both proximal end blade edges (22). Therefore, it is easy to form the side port (36) in a trapezoidal shape.
(Iii) the opposite side to the base end side cutting edges (22) (11) extends apical its both sides in the width direction of the opposite sides (11) intersect each other from (13) to the terminal unit (16), the width direction A stepped portion that forms an intermediate surface (15) between the opposite sides (11) on both sides and spreads outward at the end portion of the edge (28) extending from the end portion (16) of the opposite side (11) toward the base end side. (29) is formed. Therefore, even when the blade portion (6) is inadvertently inserted at the beginning of insertion into the cornea (35), the stepped portion (29) comes into contact with the outer peripheral surface (35a) of the cornea (35), and the cornea ( 35) Insertion of the blade part (6) into 35) can be restricted.
(D) The width direction interval (W29) between the start end portions (30a) of the end edge (30) extending from the stepped portion (29) on both sides in the width direction to the base end side is the width direction of the both blade edge (10). It is set larger than the maximum width direction interval (W19) between the end portions (19) of both base end side blade edge portions (22), and from the end portion (19) of the base end side blade edge portion (22). The widthwise interval (W25) between the end edges (25) extending to the end portion (16) of the opposite side (11) is the maximum width direction between the end portions (19) of the both base end side blade edge portions (22). It is set smaller than the interval (W19) and larger than the interval (W28) in the width direction between the end edges (28) extending from the end portion (16) of the opposite side (11) to the stepped portion (29). . . Therefore, the function of the stepped portion (29) that restricts the insertion of the blade portion (6) into the cornea (35) can be made effective.
(E) The thickness direction (Z) of the blade plate (4) between the edge portions ( 30) extending from the step portions (29) on both sides in the width direction to the proximal end side at the front portion (7) of the blade portion (6 ). The bent plate (4) is provided between the bent portion (5) and the tip (12) of the blade (6). Therefore, since a wrinkle etc. does not get in the way when inserting the blade part (6) into the cornea (35), it is easy to insert the blade part (6).
( F) The blade surface (9) along the blade edge (10) is inclined so as to reduce the thickness from the widthwise center portion side of the blade plate (4) to the outer edge portions on both sides in the width direction. 10) and an intermediate boundary edge (23) connecting the intermediate portion (20) of the opposite side (11) and the top end portion (13) of the opposite side (11), and the intermediate portion between the leading edge edge (21) and the leading edge boundary (14). The front edge side bladed surface (24) surrounded by the boundary edge (23), the proximal edge edge (22), the intermediate boundary edge (23), the opposite side (11), and the proximal edge edge (22 ) And the edge (25) between the end portions (19, 16) of the opposite side (11) and the base end side bladed surface (26) surrounded by the edge (25). Therefore, the distal side bladed surface (24) and the proximal side bladed surface (26) can be distinguished and used as a guideline for the amount of insertion of the blade part (6) into the cornea (35).
( G ) In the front surface (7) of both front and back portions (7, 8) of the blade portion (6), on the thickness direction surface passing through the front end side boundary edge (14) between the blade surfaces (9) on both sides in the width direction. On the other hand, the blade surfaces (9) on both sides in the width direction are formed symmetrically. Accordingly, the side port (36) having a trapezoidal shape can be formed in a line-symmetric shape in the width direction (Y). In addition, even when it is necessary to enlarge the side port (36) in the width direction (Y) during the operation, the trapezoidal side port (6) is simply moved in the width direction (Y). 36) can be easily increased in the width direction (Y).

(H) The following values are set for each part described above.
The bending angle (θ) of the bent portion (5) is set to 40 degrees or more and 60 degrees or less.
-The thickness (T) of the blade plate (4) is set to 0.1 mm or more and 0.25 mm or less.
The length (L5) between the pointed end (12) and the bent portion (5) between the two end side blade edges (21) is set to 3.0 mm or more and 6.0 mm or less.
3. The length (L32) between the line segment portion (32) connecting the two step portions (29) to each other and the pointed end portion (12) between both tip side blade edge portions (21) is 2.0 mm or more. It is set to 5 mm or less.
-The length between the line segment part (31) which connects the termination | terminus part (19) of both said base end side blade edge parts (22) mutually, and the pointed part (12) between both front end side blade edge parts (21) (L31) is set to 1.0 mm or more and 2.5 mm or less.
The length (L20) between the line segment part (27) connecting the intermediate parts (20) of the two blade edges (10) to each other and the pointed part (12) between the two blade edges (21) is 0. .2mm to 0.7mm.
A line segment portion (27) connecting the intermediate portions (20) of the two blade edges (10) to each other and a line segment portion (31) connecting the terminal portions (19) of the both proximal end blade edge portions (22) to each other; The length (L19) between them is set to 0.8 mm or more and 1.8 mm or less.
A length between a line segment part (31) connecting the terminal ends (19) of the both base end edge parts (22) and a line segment part (32) connecting both the step parts (29) ( L29) is set to 1.0 mm or more and 2.0 mm or less.
The opening angle (θ21) formed between the two distal edge edges (21) is set to 55 degrees or more and 90 degrees or less, and the opening angle (θ22) formed between the both proximal edges (22). Is set to 20 degrees or more and 40 degrees or less.
-The width direction space | interval (W20) between the intermediate parts (20) of the said both blade edge (10) is set to 0.2 mm or more and 0.8 mm or less.
The maximum width direction interval (W19) between the end portions (19) of the both base end side blade edge portions (22) is set to 0.5 mm or more and 1.5 mm or less.
-The width direction space | interval (W29) between the start edge part (30a) of the edge (30) extended to the base end side from both said level | step-difference part (29) is set to 1.0 mm or more and 2.0 mm or less.
A width direction interval (W25) between the end edges (25) extending from the terminal end (19) of the base end side blade edge (22) to the terminal end (16) of the opposite side (11) is 0.5 mm or more. It is set to 5 mm or less.

Therefore, since the value of such a range is set according to the thickness range of the general cornea (35), when the side port (36) is formed on the cornea (35) of the eyeball (33), the blade portion ( 6) can be made into an optimal form that is not inserted too carelessly at the beginning of insertion into the cornea (35), the side port (36) can be easily formed into a trapezoidal shape, and has excellent operability. A medical knife can be provided.

  In the present invention, even if the opening angle (θ22) formed by the two base end side blade edges (22) is set to be small to some extent to facilitate the insertion into the cornea (35), the both end side blade edges (21 ) Between the cornea (35) of the eyeball (33) and the side port (36). ) In accordance with the general thickness range of the cornea (35), the blade (6) can be in an optimal form that is not inserted too carelessly at the beginning of insertion into the cornea (35). Therefore, the side port (36) can be easily formed into a trapezoidal shape, and a medical knife excellent in operability can be provided.

(A) is a front view showing the medical knife according to the first embodiment, (b) is a partially enlarged front view of (a), (c) is a partially enlarged plan view of (a), (D) is a partial enlarged bottom view of (a). (A) is the elements on larger scale of FIG.1 (b), (b) is the elements on larger scale of FIG.1 (c) which shows the front side of a blade part, (c) is FIG. 1 which shows the back side of a blade part It is the elements on larger scale of (d). (A) is the A1-A1 sectional view taken on the line of FIG.1 (c), (b) is the A2-A2 sectional view taken on the line of FIG.1 (c), (c) is A3-A3 of FIG.1 (c). It is an A3 line partial sectional view. (A) is a partial enlarged front view of a blade part in the medical knife according to the second embodiment, (b) is a partially enlarged plan view showing the front side of the blade part, and (c) is a part of the blade part. It is a partial expanded bottom view which shows a back side. (A) is a figure equivalent to Drawing 3 (a) in a medical knife concerning a 2nd embodiment, (b) is a figure equivalent to Drawing 3 (b), and (c) is also equivalent to Drawing 3 (c). FIG. (A) is the fragmentary sectional view of the eyeball shown in order to demonstrate the usage method of a medical knife, (b) is the elements on larger scale of (a), (c) is a blade in the conventional medical knife FIG.

First, a medical knife according to a first embodiment of the present invention will be described with reference to FIGS.
The medical knife shown in FIG. 1 (a) includes a handle 1 made of synthetic resin, a handle 1 having a support plate 3 made of metal such as stainless steel, and a blade plate 4 made of metal such as stainless steel. Yes. As shown in FIG. 1B, the support plate 3 is inserted into the distal end portion of the grip portion 2, and their extending directions X1 coincide with each other. The blade plate 4 extends continuously and integrally from the support plate 3, and is bent with respect to the support plate 3 at a bent portion 5 provided at a base end portion of the blade plate 4. The extending direction X1 of the grip portion 2 and the support plate 3 in the handle 1 and the extending direction X4 of the blade plate 4 intersect each other at a bending angle θ. As shown in FIGS. 1 (c) and 1 (d), a blade portion 6 is provided on the tip portion side of the blade plate 4. The blade portion 6 of the blade plate 4 is formed on the upper side which is the extending direction side (bending direction side) of the grip portion 2 of the handle 1 and the support plate 3 among the upper and lower sides in the thickness direction Z of the blade plate 4. It has a front portion 7 and a back portion 8 formed on the lower side, which is the opposite direction to the extending direction of the grip portion 2 of the handle 1 and the support plate 3.

  As shown in FIGS. 2A, 2B, and 3C and FIGS. 3A, 3B, and 3C, the back portion 8 of the blade portion 6 is flat, and the front portion of the blade portion 6 is formed. 7, on both sides in the width direction Y of the blade plate 4 intersecting the thickness direction Z, the distance in the thickness direction Z is narrowed from the center side in the width direction Y of the blade plate 4 to the outer edge side on both sides in the width direction. An inclined blade surface 9 is formed. A blade edge 10 extending from the distal end portion of the blade portion 6 toward the proximal end portion is formed at the outer edge portion of the blade surface 9 of the front portion 7. On the blade surface 9 of the front portion 7, the opposite side 11 to the blade edge 10 extends linearly from the distal end side of the blade portion 6 to the proximal end side. In the front surface portion 7 of the blade portion 6, a pointed end portion 12 (corresponding to the tip portion of the blade plate 4 and the blade portion 6) where the blade edge 10 of the blade surface 9 on both sides in the width direction intersects each other in a V shape, Between the opposite ends 11 of the blade surfaces 9 on both sides intersect with each other in a V-shape, a tip side boundary edge 14 between the blade surfaces 9 on both sides in the width direction is formed linearly, A flat intermediate surface 15 is formed between the opposite sides 11 of the blade surface 9 on both sides in the width direction. The intermediate surface 15 forms an isosceles triangle shape that connects the top end portion 13 of both opposite sides 11 and the end portion 16 of both opposite sides 11 to each other. The base end portion of the blade portion 6 corresponds to a line segment portion 17 that connects the end portions 16 of the opposite sides 11 to each other. The intermediate surface 15 of the front portion 7 of the blade portion 6 and the flat surface 18 of the back portion 8 of the blade portion 6 are formed in parallel to each other. In the front portion 7 of the blade portion 6, the blade surfaces 9 on both sides in the width direction are formed symmetrically with respect to the thickness direction surface passing through the front end side boundary edge 14 between the blade surfaces 9 on both sides in the width direction.

The blade edge 10 on both sides in the width direction has an intermediate portion 20 that bulges outward between the tip portion 12 and the terminal portion 19, and a tip-side blade edge portion 21 that connects the tip portion 12 and the intermediate portion 20 in a straight line. The base portion side edge portion 22 connects the intermediate portion 20 and the end portion 19 in a straight line parallel to the opposite side 11. The opening angle θ21 formed by the both distal end side blade edges 21 is set to be larger than the opening angle θ22 formed by the both proximal side blade edges 22 with each other. The blade surface 9 along the blade edge 10 is defined by an intermediate boundary edge 23 that linearly connects the intermediate portion 20 and the top end portion 13, and the tip-side blade edge portion 21, the tip-side boundary edge 14, and the intermediate boundary edge 23 The proximal side bladed surface 26 surrounded by the enclosed distal side bladed surface 24, the proximal side blade edge part 22, the intermediate boundary edge 23, the opposite side 11, and the edge 25 between the terminal parts 16 and 19. It consists of. A line segment portion 27 that connects both the intermediate portions 20 intersects the tip end side boundary edge 14 at a crossing portion 27a between the apex portion 12 and the apex portion 13 in the vicinity of the apex portion 13 at a right angle. Of the distances in the width direction of both blade edges 10, the width direction distance W 19 between the end portions 19 of both base end side blade edges 22 is set to be larger than the width direction distance W 20 between both intermediate portions 20. Yes.

Note that the intersection where the intermediate boundary edge 23 intersects the front boundary edge 14 or the opposite side 11 may coincide with the top end 13 of the opposite side 11, but is located in the vicinity of the top end 13 of the opposite side 11. even if well, since a state of intersection of the intermediate boundary edge 23 intersects the distal side boundary edge 14 or opposite side 11 gathered on the top end portion 13 of the opposite sides 11 in that case, the distal end side bladed surface 24 and the base It can be distinguished from the end-side bladed surface 26 and can be used as a guideline for the amount of insertion of the blade portion 6 into the cornea 35.

  End edges 28 extend in parallel from the end portions 16 of the opposite sides 11 to the base end side, and stepped portions 29 are formed spreading outward at the end portions of the both end edges 28. The width direction interval W29 between the start end portions 30a of the end edges 30 extending from the both stepped portions 29 to the proximal end side (outer end portions of the stepped portions 29) is the both proximal end side blades of the widthwise intervals of the two blade leading edges 10. It is set larger than the maximum width direction interval W19 between the end portions 19 of the edge portion 22. The widthwise intervals W25, W28 between the end edges 25, 28 extending from the end portion 19 of the base end side blade edge portion 22 through the end portion 16 of the opposite side 11 to the stepped portion 29 are defined as both base end side blade edges. It is set smaller than the maximum width direction interval W19 between the end portions 19 of the portion 22. The bent portion 5 bent from the back portion 8 side to the front portion 7 side of the blade portion 6 is provided between the edge portions 30 extending from the step portions 29 on both sides in the width direction to the proximal end side, and the bent portion 5 and the blade The blade plate 4 is provided between the pointed portion 12 of the portion 6.

About the medical knife concerning 2nd Embodiment shown in FIGS. 4-5, the 1st Embodiment shown in FIGS. 1-3 and a basic form are the same.
About the medical knife concerning 1st Embodiment or 2nd Embodiment, it is preferable to set each part in the following range.

  The bending angle θ shown in FIG. 1B is set to 30 ° to 90 °, more preferably 40 ° to 60 °. In both the first embodiment and the second embodiment, the bending angle θ is set to about 45 degrees.

  -As shown in Drawing 1 (b), thickness T of blade board 4 is set as 0.05 mm or more and 0.5 mm or less, more preferably 0.1 mm or more and 0.25 mm or less. In both the first embodiment and the second embodiment, the thickness T is set to about 0.15 mm.

  -As shown in Drawing 1 (b), length L5 between tip part 12 and bent part 5 is set as 2 mm or more and 10 mm or less, more preferably 3.0 mm or more and 6.0 mm or less. In the first embodiment, the length L5 is set to about 4.5 mm, and in the second embodiment, the length L5 is set to about 4.0 mm.

  -As shown in FIG.2 and FIG.4, length L32 between the line segment part 32 which connects both the level | step-difference parts 29 mutually and the pointed part 12 is 1.0 mm or more and 5.0 mm or less, More preferably, it is 2.0 mm or more Set to 4.5 mm or less. In the first embodiment shown in FIG. 2, the length L32 is set to 3.5 mm. In the second embodiment shown in FIG. 4, the length L32 is set to about 3.0 mm.

  -As shown in FIG.2 and FIG.4, length L31 between the line segment part 31 which connects the terminal part 19 of both base end side blade edge parts 22 and the pointed part 12 is 0.8 mm or more and 3.0 mm or less More preferably, it is set to 1.0 mm or more and 2.5 mm or less. In the first embodiment shown in FIG. 2, the length L31 is set to about 2.0 mm. In the second embodiment shown in FIG. 4, the length L31 is set to about 1.7 mm.

  -As shown in FIG.2 and FIG.4, length L20 between the line segment part 27 which connects both the intermediate parts 20 mutually and the pointed part 12 is 0.2 mm or more and 1.0 mm or less, More preferably, 0.2 mm or more Set to 0.7 mm or less. In the first embodiment shown in FIG. 2, the length L20 is set to about 0.4 mm. In the second embodiment shown in FIG. 4, the length L20 is set to about 0.4 mm.

  2 and 4, as shown in FIG. 2 and FIG. 4, a length L19 between a line segment portion 27 connecting the intermediate portions 20 to each other and a line segment portion 31 connecting the terminal ends 19 of the both base end side blade edges 22 to each other is set. It is set to 0.6 mm or more and 2.0 mm or less, more preferably 0.8 mm or more and 1.8 mm or less. In the first embodiment shown in FIG. 2, the length L19 is set to about 1.6 mm. In the second embodiment shown in FIG. 4, the length L19 is set to about 1.3 mm.

  As shown in FIGS. 2 and 4, a length L 29 between a line segment portion 31 that connects the end portions 19 of both base end side blade edges 22 to each other and a line segment portion 32 that connects both step portions 29 to each other is set. It is set to 0.2 mm or more and 2.0 mm or less, more preferably 1.0 mm or more and 2.0 mm or less. In the first embodiment shown in FIG. 2, the length L29 is set to about 1.5 mm. In the second embodiment shown in FIG. 4, the length L29 is set to about 1.3 mm.

  As shown in FIGS. 2 and 4, the opening angle θ21 formed by the two leading edge edges 21 is set to 45 degrees or more and 100 degrees or less, more preferably 55 degrees or more and 90 degrees or less. The opening angle θ22 formed by the blade edge portions 22 is set to 10 ° to 50 °, more preferably 20 ° to 40 °. In the first embodiment shown in FIG. 2, the opening angle θ21 is set to about 60 degrees, and the opening angle θ22 is set to about 25 degrees. In the second embodiment shown in FIG. 4, the opening angle θ21 is set to about 60 degrees, and the opening angle θ22 is set to about 30 degrees.

  -As shown in FIG.2 and FIG.4, the width direction space | interval W20 between both the intermediate parts 20 is set to 0.2 mm or more and 1.0 mm or less, More preferably, it is set to 0.2 mm or more and 0.8 mm or less. In the first embodiment shown in FIG. 2, the widthwise interval W20 is set to about 0.5 mm. In the second embodiment shown in FIG. 4, the width direction interval W20 is set to about 0.5 mm.

  -As shown in FIG.2 and FIG.4, the maximum width direction space | interval W19 between the terminal parts 19 of both base end side blade edge parts 22 is 0.5 mm or more and 1.8 mm or less, More preferably, 0.5 mm or more and 1.5 mm Set as follows. In the first embodiment shown in FIG. 2, the maximum width direction interval W19 is set to about 1.2 mm. In the second embodiment shown in FIG. 4, the maximum width direction interval W19 is set to about 1.2 mm.

  2 and 4, as shown in FIGS. 2 and 4, a widthwise interval W29 between the start end portion 30a (the outer end portion of the stepped portion 29) of the edge 30 extending from both stepped portions 29 to the proximal end side is 1.0 mm or more. It is set to 0 mm or less, more preferably 1.0 mm to 2.0 mm. In the first embodiment shown in FIG. 2, the width direction interval W29 is set to about 1.4 mm. In the second embodiment shown in FIG. 4, the width direction interval W29 is set to about 1.4 mm.

  As shown in FIGS. 2 and 4, between the end edges 25, 28 extending from the terminal end 19 of the base end side blade edge 22 through the terminal end 16 of the opposite side 11 to the stepped portion 29, between both end edges 28. The width direction interval W28 is set to 0.5 mm or more and W19 or less, more preferably 0.5 mm or more and 1.5 mm or less. In the first embodiment shown in FIG. 2, the widthwise interval W28 is set to about 1.0 mm. In the second embodiment shown in FIG. 4, the width-direction interval W28 is set to about 1.0 mm. In addition, the width direction interval W25 between both end edges 25 is set smaller than the width direction interval W19 and larger than the width direction interval W28.

  When the medical knife according to the first embodiment and the second embodiment is used for cataract surgery, the cornea 35 of the eyeball 33 mainly has an eye as shown in FIGS. 6 (a) and 6 (b). In addition to the main port (incision) used when inserting the inner lens, a side port 36 (incision) is formed at a position having a predetermined circumferential angle with respect to the main port around the crystalline lens 34. At the time of the formation, first, the tip 12 of the blade edge 10 contacts the outer peripheral surface 35a of the cornea 35 (the outer peripheral surface of the cornea 35), then both the blade edges 21 cut the cornea 35, and then Both proximal edge edges 22 cut through the cornea 35. The pointed portion 12 passes through the inner peripheral surface 35b of the cornea 35 (the inner peripheral surface of the cornea 35), the intermediate portion 20 of the two cutting edges 10 slightly passes through the inner peripheral surface 35b, and the terminal portion 19 of the two cutting edges 10. Is inserted until just before passing the outer peripheral surface 35a of the cornea 35, a side port 36 is formed between the outer peripheral surface 35a and the inner peripheral surface 35b of the cornea 35. In the side port 36, the form in which the outer incision line 36a formed in the outer peripheral surface 35a and the inner incision line 36b formed in the inner peripheral surface 35b are connected from the outer incision line 36a of the outer peripheral surface 35a. It forms in the trapezoid shape which narrows gradually as it goes to the incision line 36b of the inner peripheral surface 35b.

This embodiment has the following effects.
(1) In the medical knife of the form shown in FIG. 6C exemplarily shown in the prior art, the line segment portions 27 that connect the intermediate portions 20 on both sides in the width direction are both the distal edge portions 21 and the proximal ends. From the top end portion 13 to the extension line 37 of the tip side boundary edge 14 connecting the top end portion 13 where the opposite sides 11 with respect to the blade edge portion 22 intersect with each other and the tip end portion 12 where both tip side blade edge portions 21 cross each other. It intersects at the intersection 27a on the base end side. However, as shown in FIGS. 6 (a) and 6 (b), in this embodiment, the line segment portion 27 that connects the intermediate portions 20 on both sides in the width direction intersects with the opposite sides 11 with respect to both base end side blade edges 22. In the vicinity of the top end portion 13 between the tip end portion 12 and the top end portion 13, with respect to the tip end side boundary edge 14 connecting the top end portion 13 and the tip end portion 12 where the both end side blade edge portions 21 intersect each other . It intersects at the intersection 27a . Therefore, when the medical knife of the present embodiment is compared with the medical knife shown in FIG. 6 (c), even if the opening angle θ22 formed by the two proximal end blade edges 22 is set to the same value, As for the opening angle θ21 formed by the two leading edge edges 21, the medical knife of this embodiment can be set to a larger value. Thus, since it becomes easy to set the opening angle θ21 formed between the two tip side blade edge portions 21 to each other, when the side port 36 is formed in the cornea 35 of the eyeball 33, the blade portion 6 is initially inserted into the cornea 35. It is possible to provide a medical knife excellent in operability by making it easy to form the side port 36 into a trapezoidal shape without inadvertent insertion. Therefore, when various instruments are inserted / removed or operated at the side port 36, the contact of the various instruments with the side port 36 is reduced, and the insertion / removal and operations are facilitated. Further, it is possible to prevent the blade portion 6 from being inadvertently inserted into the cornea 35 or damaging the anterior lens capsule. In addition, even when the opening angle θ22 formed by the both base end side blade edge portions 22 is reduced, if the opening angle θ21 formed by the both end side blade edge portions 21 is increased, the pointed end portion 12 of the blade portion 6 is not easily deformed. .

(2) The following values are set for the respective parts described above according to the thickness range (for example, about 0.7 mm) of the general cornea 35.
The bending angle θ is set to 40 degrees or more and 60 degrees or less.
The thickness T of the blade plate 4 is set to 0.1 mm or more and 0.25 mm or less.
The length L5 between the pointed portion 12 and the bent portion 5 is set to 3.0 mm or more and 6.0 mm or less.
The length L32 between the line segment portion 32 connecting the both step portions 29 and the pointed end portion 12 is set to 2.0 mm or more and 4.5 mm or less.
The length L31 between the line segment portion 31 connecting the both end portions 19 and the pointed end portion 12 is set to 1.0 mm or more and 2.5 mm or less.
The length L20 between the line segment portion 27 connecting the two intermediate portions 20 and the pointed portion 12 is set to 0.2 mm or more and 0.7 mm or less.
The length L19 between the line segment portion 27 connecting the intermediate portions 20 and the line segment portion 31 connecting the end portions 19 is set to 0.8 mm or more and 1.8 mm or less.
The length L29 between the line segment portion 31 connecting the both end portions 19 and the line segment portion 32 connecting the both step portions 29 is set to 1.0 mm or more and 2.0 mm or less.
The opening angle θ21 between the two leading edge edges 21 is set to 55 degrees or more and 90 degrees or less, and the opening angle θ22 between the both proximal edges 22 is set to 20 degrees or more and 40 degrees or less. ing.
-The widthwise interval W20 between the intermediate portions 20 is set to 0.2 mm or more and 0.8 mm or less.
The maximum width direction interval W19 between the end portions 19 is set to 0.5 mm or more and 1.5 mm or less.
The widthwise interval W29 between the start end portions 30a of the end edge 30 extending from both the stepped portions 29 to the base end side is set to 1.0 mm or more and 2.0 mm or less.
The widthwise interval W25 between the end edges 25 extending from the end portion 19 of the base end side blade edge portion 22 to the end portion 16 of the opposite side 11 is set to 0.5 mm or more and 1.5 mm or less.
Since the above-mentioned values are set for the respective parts described above, when the side port 36 is formed on the cornea 35 of the eyeball 33, the blade part 6 should be in an optimal form that is not inserted too carelessly at the beginning of insertion into the cornea 35. The side port 36 can be easily formed into a trapezoidal shape, and a medical knife excellent in operability can be provided. Therefore, when various instruments are inserted / removed or operated at the side port 36, the contact of the various instruments with the side port 36 is reduced, and the insertion / removal and operations are facilitated. Further, the side port 36 does not become larger than necessary, and the wound is easily cured.

  (3) Since the stepped portion 29 extending outward is formed at the end portions of the end edges 25 and 28 extending from the end portions 16 of the opposite sides 11 to the base end side, the stepped portion 29 is in contact with the outer peripheral surface 35a of the cornea 35. Even when the blade portion 6 is inadvertently inserted excessively at the beginning of insertion into the cornea 35, the insertion into the cornea 35 can be restricted.

  (4) A bent portion 5 bent in the thickness direction Z of the blade plate 4 is provided between the edge portions 30 extending from the stepped portions 29 on both sides in the width direction to the proximal end side, and the bent portion 5 and the tip portion of the blade portion 6 are provided. Since the blade plate 4 is provided between the blade portion 12 and the blade 12, the blade portion 6 does not get in the way when the blade portion 6 is inserted into the cornea 35, so that the blade portion 6 can be easily inserted.

  (5) Since the blade surfaces 9 on both sides in the width direction are formed in a symmetric shape in the front portion 7 of the blade portion 6, the trapezoidal side port 36 is formed in a line symmetric shape in the width direction Y. In addition, even when it is necessary to enlarge the side port 36 in the width direction Y during the operation, the trapezoidal side port 36 is moved in the width direction Y simply by moving the blade portion 6 in the width direction Y. Can be easily enlarged.

  The tip-side blade edge 21 and the base-end blade edge 22 may be formed in a curved shape that swells outward or inward in addition to a straight shape, and in that case, the blade edge that continues in a wave shape is linear. Alternatively, it may be formed to extend in a curved shape.

A slight radius may be given to the intermediate portion 20 and the end portion 19 of the blade edge 10.
For example, the whole or a part of the blade plate 4 or the blade part 6 may be formed of diamond, titanium, or a titanium alloy, and the blade part 6 or a part thereof may be provided separately on the blade plate 4. .

  -The front part 7 and the back part 8 of the blade part 6 may be subjected to fluorine coating or silicone coating. Further, the blade surface 9 may be subjected to a hardening process such as nitriding or carbonizing, or a hardened layer may be provided by a surface treatment.

-The front part 7 and the back part 8 of the blade part 6 may be provided with a display or coloring indicating the type and size of the blade part 6.
-A line, a mark, or a scale that can be visually recognized so that the insertion amount and position of the blade portion 6 can be confirmed during the operation at the portion corresponding to the line segment portion 27 and the line segment portion 31 in the front portion 7 of the blade portion 6. You may attach.

4 ... blade plate, 5 ... bent portion, 6 ... blade portion, 7 ... front portion, 8 ... back portion, 9 ... blade surface, 10 ... blade edge, 11 ... opposite side, 12 ... pointed end, 13 ... top end, 14 ... distal end side boundary edge, 15 ... intermediate surface, 16 ... end part, 19 ... end part, 20 ... intermediate part, 21 ... front end side blade edge part, 22 ... proximal end side blade edge part, 23 ... intermediate boundary edge, 24 ... distal end cutting surface, 25 ... end edge, 26 ... proximal end cutting surface, 27 ... line segment part, 27a ... intersection, 28 ... end edge, 29 ... stepped part, 30 ... end edge, 30a ... start edge , 31 ... line segment part, T ... thickness, θ ... bending angle , θ21 ... opening angle, θ22 ... opening angle, W19 ... width direction interval, W20 ... width direction interval, W25 ... width direction interval, W28 ... width direction interval , W29 ... widthwise spacing, L5 ... length, L19 ... length, L20 ... length, L29 ... length, L31 ... length, L32 ... length, Z ... thickness Direction, Y ... width direction.

Claims (1)

The blade portion having a front and back both parts in the thickness direction of the blade plate is provided, from its tip as to intersect each other at the tip portion on both sides in the width direction intersecting the thickness direction out table portion of the front and back both portions of the blade section A blade surface extending along the edge of the blade extending to the end portion is formed, and the interval in the width direction of both the edge of the blade gradually increases from the tip portion toward the end portion,
The blade edges on both sides in the width direction are partitioned by an intermediate portion that bulges outward between the tip portion and the end portion, and connects the tip side blade edge portion connecting the tip portion and the intermediate portion, and the intermediate portion and the end portion. A base-side blade edge, and an opening angle formed by the two distal-end blade edges is set larger than an opening angle formed by the both base-side blade edges.
The line segment part connecting the intermediate parts on both sides in the width direction is the front end side boundary edge connecting the apex part where the opposite sides to the base end edge part intersect each other and the apex part where the end side edge part intersects each other On the other hand, it intersects with the intersection between the apex and the apex in the vicinity of the apex ,
The blade surface along the blade edge is inclined so as to decrease in thickness from the width direction central portion side of the blade plate to the outer edge portions on both sides in the width direction, and is an intermediate boundary connecting the top end portion of the opposite side and the intermediate portion of the blade edge. A tip-side bladed surface defined by an edge and surrounded by a tip-side blade edge, a tip-side boundary edge, and an intermediate boundary edge, a base-side blade edge, an intermediate boundary edge, an opposite side, and a base-side blade edge And a base end side bladed surface surrounded by an edge between the end portions of the opposite side,
In the front portion of the blade portion, the blade surfaces on both sides in the width direction are formed symmetrically with respect to the thickness direction surface passing through the tip side boundary edge between the tip side bladed surfaces on both sides in the width direction,
Opposite side with respect to the proximal-side cutting edge extends up to an end from the top end, so as to form an intermediate surface between both sides in the width direction of the opposite side, at the end of the edges from the end portions of the opposite sides extending proximally Form a stepped part that spreads outward,
The width direction interval between the start end portions of the end edges extending from the step portions on both sides in the width direction to the base end side is set larger than the width direction interval between the end portions of both base end side blade edge portions. The width direction interval between the end edges extending from the end portion of the edge portion to the end portion of the opposite side is set to be smaller than the width direction interval between the end portions of the both edge side blade edges, and the end portion of the opposite side Is set to be larger than the interval in the width direction between the edges extending from the step portion to the step portion,
A bent portion bent in the thickness direction of the blade plate at the front portion of the blade portion is provided between the edge portions extending from the step portions on both sides in the width direction to the proximal end side, and between the bent portion and the sharp end portion of the blade portion. The blade plate is provided with
The bending angle of the bent portion is set to 40 degrees or more and 60 degrees or less,
The thickness of the blade plate is set to 0.1 mm or more and 0.25 mm or less,
The length between the sharp tip and the bent part between the two tip side blade edges is set to 3.0 mm or more and 6.0 mm or less,
The length between the line segment portion connecting the two stepped portions to each other and the tip portion between both tip side blade edges is set to 2.0 mm or more and 4.5 mm or less,
The length between the line segment portion connecting the terminal ends of the both base end side blade edges and the pointed end between both end side blade edges is set to 1.0 mm or more and 2.5 mm or less,
The length between the line segment part connecting the middle parts of the two blade edges to each other and the tip part between the two tip side blade edges is set to 0.2 mm or more and 0.7 mm or less,
The length between the line segment part connecting the middle parts of the two blade edges to each other and the line segment part connecting the terminal parts of both base end side blade edge parts to each other is set to 0.8 mm or more and 1.8 mm or less,
The length between the line segment part connecting the terminal ends of the both proximal end blade edges and the line segment part connecting the two stepped parts to each other is set to 1.0 mm or more and 2.0 mm or less,
The opening angle formed by the two distal end side blade edges is set to 55 degrees or more and 90 degrees or less, and the opening angle formed by the both proximal end blade edges is set to 20 degrees or more and 40 degrees or less,
The widthwise interval between the intermediate portions of the two blade edges is set to 0.2 mm or more and 0.8 mm or less,
The maximum width direction interval between the terminal ends of the both base end side blade edges is set to 0.5 mm or more and 1.5 mm or less,
The width direction interval between the start end portions of the edge extending from the both stepped portions to the base end side is set to 1.0 mm or more and 2.0 mm or less,
A medical knife characterized in that a widthwise interval between both end edges extending from the terminal end of the base end side blade edge to the terminal end of the opposite side is set to 0.5 mm or more and 1.5 mm or less. .