JP3977070B2 - Cornea surgery instrument - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a corneal surgical instrument for peeling a corneal epithelium in a flap shape.
[0002]
[Prior art]
In recent years, for corneal refraction surgery, the corneal epithelium cut into a circular shape with a hinge partially removed using a corneal resection machine is dipped in alcohol and expanded, and then peeled off from the Bowman membrane with a golf scalpel or the like. The LASEK operation (Laser Epithelial Keratomileusis), in which a corneal stroma is excised by an amount of corrective refraction by excimer laser light and the corneal epithelial flap is returned again, has attracted attention. Recently, it has been considered that a thin wire (with a wire diameter of about 50 μm) is pressed against the eyeball without using alcohol, the wire is vibrated in the axial direction, and only the corneal epithelium is peeled off in a flap shape.
[0003]
[Problems to be solved by the invention]
However, since the corneal epithelium is peeled off while pressing the eyeball with the wire, the wire needs to have a tensile strength, but there is a problem that a thin wire breaks if a slight force is applied. If the wire is thick, smooth detachment of the corneal epithelium is difficult.
[0004]
In view of the problems of the conventional apparatus, it is an object of the present invention to provide a corneal surgical instrument that can smoothly peel a corneal epithelium and create a flap while avoiding breakage of a flap forming blade.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is characterized by having the following configuration.
[0006]
(1) In a corneal surgical instrument that includes a belt-like blade that presses against an eyeball and peels off the corneal epithelium and a holder that holds the blade, and peels off the corneal epithelium from which the edge for creating the flap has been cut in advance The blade has a width of 1 to 70 μm at the tip of the blade, the corner of the tip is rounded with a radius of 0.5 to 35 μm, and the eyeball can be flattened linearly when pressed against the eyeball. The blade body has a thickness of 0.2 to 3 mm, and the angle formed by the two blade attachment surfaces is 10 to 70 ° .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an external view of a corneal surgical instrument according to the present invention. Reference numeral 1 denotes a corneal surgical instrument body, which includes a belt-like blade 4 for peeling off the corneal epithelium and an arcuate frame 2 as a holder for supporting the blade 4. The frame 2 is rotatable about the shaft 2a, and the interval (tensile strength) between both ends of the frame that supports the blade 4 can be adjusted. Reference numeral 2b denotes a grip portion that is held by a surgeon with a finger during surgery, and is provided integrally with the frame 2.
[0012]
Reference numeral 3 denotes a screw rod that opens and closes the frame 2 like a compass used for drawing. 2c provided on the frame 2 is a female screw that meshes with the male screw 3a. The female screw 2c and the male screw 3a are right-hand screws. Reference numeral 2d denotes a female screw that meshes with the male screw 3b, and the female screw 2d and the male screw 3b are left screws. Reference numeral 3 c denotes a knob provided at the center of the screw rod 3. By rotating the knob 3c, both ends of the frame 2 can be opened and closed with the shaft 2a as the center of rotation.
[0013]
The blade 4 shown in FIG. 1 is made of a strip-shaped thin steel plate, and is fitted into attachment groove 2e formed at both ends of the frame 2, respectively. Bending portions 4a are provided at both ends in the longitudinal direction of the blade 4, and the bending portions 4a are hooked outside the attachment portion grooves 2e. When the thin steel plate is thin, a thick block may be fixed instead of the bent portion 4a. The blade 4 of the thin steel plate is a metal blade such as stainless steel or steel.
[0014]
The cutting edge dimension A (the dimension between both ends of the frame 2 in FIG. 1) extending in the longitudinal direction of the blade 4 is preferably about 10 mm to 30 mm in view of the movement amount of the lateral vibration of the blade 4. In this embodiment, it is 15 mm. The plate thickness B is preferably 5 to 70 μm, and in the present example, 20 μm. In order to smoothly peel the corneal epithelium, it is preferable that the thickness B of the blade 4 is thin to some extent, but if it is too thin, the strength is lost. The width C in the cross-sectional direction of the cutting edge is set so as to ensure the strength that does not break when the blade 4 is tensioned. However, if the width C is long, the peeled corneal epithelium tends to stick. Therefore, the width C is preferably 0.3 to 5 mm, more preferably 0.5 to 2 mm. In this embodiment, it is 1 mm. When the plate thickness B is reduced, the width C is preferably relatively long.
[0015]
FIG. 2 shows an enlarged view of a partial cross section of the blade 4. The blade 4 of the thin steel plate has a bladed surface formed by its upper and lower surfaces (the two bladed surfaces are parallel), and the corner between the bladed surface and the blade tip 4b has a rounded radius R. Beveled. This is because if the corners between the blade edge 4b and the blade attachment surface are made acute, the Bowman film can be easily cut. The rounding radius R is preferably 0.5 μm or more. As for the rounding size, various radii R can be designed with respect to the plate thickness B as shown in FIGS. When the plate thickness B is set to 70 μm and uniform rounding is performed up to the blade tip 4c as shown in FIG. 2C, the rounding radius R is set to 35 μm. FIG.2 (b) is an example at the time of leaving a linear part at the blade-tip point. Such rounding of the chamfer can be performed by electropolishing. It is preferable to finish so that there is no burr etc. from the double-edged surface to the blade tip 4b.
[0016]
When attaching the blade 4 to the frame 2, first, the knob 3c is rotated, and the blade 4 is fitted into the attachment portion groove 2e in a state where the tip end portion (attachment portion groove 2e side) of the frame 2 is narrowed. Thereafter, the knob 3c is rotated in the opposite direction to widen the tip of the frame 2, and the knob 3c is rotated until the bent portion 4a of the blade 4 is pressed against the mounting portion groove 2e. Fix to 2e. Further, the tension of the blade 4 is adjusted by turning the knob 3c. This tension adjustment causes the eyeball to be flattened linearly when the lower surface (or the tip of the blade tip) of the blade 4 is pressed against the eyeball.
[0017]
As a method for fixing the blade, a method may be used in which a hole 4′a is formed in the blade 4 ′ as shown in FIG.
[0018]
In the apparatus having the above configuration, the corneal epithelial flap creation operation will be described below.
[0019]
First, as shown in FIG. 4, a corneal epithelium 20 is removed from the corneal epithelium 20 by using a corneal circular excision machine, a golf scalpel, etc. The edge of is previously formed. Next, holding the grip 2b of the frame 2 with a finger and inserting the blade 4 into the annular region 21 with the blade tip sharpened as shown in FIG. Advance forward (D direction) while vibrating in the longitudinal direction. At this time, as shown in FIG. 6, the eyeball is pressed against the lower surface of the blade 4 to flatten the cornea. Since the corner of the tip of the blade 4 has a rounded chamfer R, it slides on the relatively hard Bowman film 31. When the blade 4 is advanced forward while being laterally oscillated, the corneal epithelium 20 is peeled off from the Bowman membrane 31, and a layered epithelial flap 20a is formed. Since the blade 4 is a strip-shaped thin steel plate, a smooth corneal epithelium flap can be created while avoiding breakage when the eyeball is pressed.
[0020]
When the flap 20a is formed in the entire inside of the annular region 21, the surgical instrument body 1 is removed from the affected area. After that, the flap 20a is turned over, a laser beam is used to perform a substantial excision of the corrective refractive power, and the flap 20a is returned to complete the operation.
[0021]
FIG. 7A is a diagram showing a modification example of the blade. The blade 40 in this figure has a strength that is increased by adding the thickness of the entire blade body to the strip-shaped thin steel plate of the previous example, and is not deformed when pressed against the eyeball. The material of the blade 40 can be made of a resin material in addition to a metal such as stainless steel or steel. The resin material may be a polyacetal resin or the like, but is preferably a fluororesin (PTFE or the like) or a hydrophilic resin with good sliding properties. In the case of resin, its shape is wedge-shaped because its rigidity is lower than that of metal. In addition, considering the disposable type, the cost can be reduced if it is made by resin molding.
[0022]
In the blade 40, the blade thickness B is preferably 0.2 to 3 mm, and in this example, 2 mm. The cutting edge dimension extending in the longitudinal direction is preferably about 10 mm to 30 mm as in the previous example, and is set to 15 mm in this example. Further, the dimension C in the direction of the cutting edge cross section is preferably 1 to 5 mm in the case of metal, and may be 10 mm in the case of resin having good slipperiness. In the example shown in FIG. 7, the resin has good sliding property and the dimension C is about 5 mm. Note that the two holes 41 are provided to support the blade 40 by the shaft 2'e provided at the tip of the frame 2 shown in FIG.
[0023]
7B and 7C are partial cross-sectional views of the blade edge 43. FIG. The two blade attachment surfaces 42 toward the tip of the blade tip are inclined, and the angle θ formed by the blade attachment surfaces 42 is preferably 10 to 70 °, and in this example, 25 °. The height (width) W at the cutting edge tip 43 is preferably 1 to 70 μm. The corners of the two blade mounting surfaces and the blade tip 43 are chamfered with a rounded radius R as in the previous example. The rounding radius R is preferably 0.5 to 35 μm. FIG. 7 (b) shows a case where uniform rounding is applied up to the blade tip 43, and FIG. 7 (c) shows an example where rounding is performed leaving a straight portion. By attaching the blade 40 to the distal end portion of the surgical instrument main body 1, the flap 20a of the corneal epithelium 20 can be created in the same manner as described above.
[0024]
In the above description, the operation is performed by manually vibrating the blade. However, the present invention is not limited to this, and the blade portion may be vibrated using a power source such as a motor as in an electric shaving.
[0025]
【The invention's effect】
As described above, according to the present invention, a corneal epithelial flap can be formed smoothly while avoiding breakage of the flap creating blade.
[Brief description of the drawings]
FIG. 1 is an external view of a corneal surgical instrument according to an embodiment.
FIG. 2 is a cross-sectional view of a blade.
FIG. 3 is an external view of a modified example of a corneal surgical instrument.
FIG. 4 is a diagram for explaining a corneal epithelium excised in an annular shape.
FIG. 5 is a diagram illustrating a flap of a stratified corneal epithelium.
FIG. 6 is a diagram for explaining a flap of a stratified corneal epithelium.
FIG. 7 is a diagram for explaining a modification example of a blade.
[Explanation of symbols]
1 Cornea surgical instrument body 2 Frame 3 Screw rod 4 Blade 40 Blade

Claims (1)

A corneal surgical instrument comprising a strip-shaped blade that is pressed against an eyeball to peel the corneal epithelium and a holder that holds the blade, and the corneal epithelium is peeled off in a flap shape by removing the edge for flap creation in advance. Has a thickness of 1 to 70 μm at the tip of the blade tip, a corner of the tip is rounded with a radius of 0.5 to 35 μm, and a thickness that enables the eyeball to be flattened linearly when pressed against the eyeball A corneal surgical instrument having a blade body of 0.2 to 3 mm and having an angle formed by two blade attachment surfaces of 10 to 70 ° .

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