Intraocular lens insertion device

Abstract

To provide an intraocular lens inserter that suppresses unintended axial misalignment of the extrusion member in the plunger caused by stress associated with the folding of the intraocular lens. [Solution] The intraocular lens insertion device 10 has a proximal end protrusion (first protrusion) and a tip end protrusion (second protrusion) that extend from the outer surface of a part of the outer surface of the extrusion member 330 in a direction intersecting the axial direction of the extrusion shaft A. When the extrusion member 330 moves along the passage of the extrusion shaft A inside the main body 100, if a stress due to the folding of the intraocular lens 1 acts on the extrusion member 330 that causes the extrusion member 330 to deviate from its intended trajectory, the proximal end protrusion (first protrusion) and the tip end protrusion (second protrusion) come into contact with a part of the passage of the main body 100 before the outer surface, and function as a counter mechanism to apply stress to the extrusion member 330 that returns it to its intended trajectory.

Description

Technical Field

[0001] The present disclosure relates to an intraocular lens insertion instrument for inserting an intraocular lens into the eye.

Background Art

[0002] Conventionally, as one of the surgical methods for cataract, a method of inserting a foldable soft intraocular lens into the eye instead of the crystalline lens is generally used. Also, in order to correct the refractive power of the eye, the intraocular lens may be inserted anterior to the crystalline lens. For the insertion of the intraocular lens into the eye, an intraocular lens insertion instrument called an injector may be used.

[0003] As such an injector, an intraocular lens is folded small and ejected from the tip by pushing the intraocular lens along the extrusion axis with an extrusion member in a plunger inside a nozzle having a hollow passage whose passage area through which the intraocular lens passes gradually decreases toward the tip. (See, for example, Patent Document 1). Patent Document 1 discloses a technique having a movable piece that functions to suppress so-called axial deviation so that the plunger is positioned at the center in the left-right direction of the main body portion when the plunger moves inside the main body portion of the intraocular lens insertion instrument.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, in the case of an injector, it is inserted through the incision made in the cornea. In recent years, there has been an increasing trend towards minimizing incisions in cataract surgery. That is, in order to meet the demand for minimally invasive surgery, it is desirable to make the insertion part, which is the tip of the injector nozzle, thinner. Here, as the insertion part of the intraocular lens insertion device becomes thinner, the filling rate of the intraocular lens around the compressed tip of the extruder tends to increase as the intraocular lens, which is folded into a small size within the insertion part by the extrusion of the extruder, passes through the insertion part. When the compressed intraocular lens is pushed out of the nozzle by the extruder, the stress associated with the folding of the intraocular lens is exerted on the extruder. Due to this stress associated with the folding of the intraocular lens, the extruder tends to displace in the direction of axial misalignment beyond its intended trajectory, which can cause unintended axial misalignment of the extruder. Unintended misalignment of the extrusion member can cause the intraocular lens to rotate in one direction around the extrusion axis, leading to the outer edge (also called the edge) of the optical portion rotating towards the gap between the extrusion member and the insertion portion. This can cause microscopic cracks to form as the outer edge enters the gap. Furthermore, depending on how the intraocular lens insertion device is used, if the extrusion speed is slow or intermittent, the frictional resistance applied to the intraocular lens fluctuates, resulting in unstable behavior of the intraocular lens due to unintended misalignment of the extrusion member. This makes the intraocular lens more prone to rotation when folded.

[0006] However, the technology disclosed in Patent Document 1 merely aims to suppress axial misalignment by positioning the plunger in the center in the left-right direction within the main body, but it does not consider improvement to prevent unintended axial misalignment of the extruded member due to stress associated with the folding of the intraocular lens. In other words, further improvements were desired in technology to suppress unintended axial misalignment of the extruded member in the plunger due to stress associated with the folding of the intraocular lens.

[0007] Therefore, this disclosure has been made to solve the above-mentioned problems, and aims to provide an intraocular lens insertion device that suppresses unintended axial misalignment of the extrusion member in the plunger caused by stress associated with the folding of the intraocular lens. [Means for solving the problem]

[0008] An intraocular lens insertion device provided by a typical embodiment of the present disclosure is an intraocular lens insertion device that inserts an intraocular lens, which is placed in the internal space of a cylindrical main body, into the eye by pushing the intraocular lens out from the axial rear side to the axial front side of the main body with a rod-shaped extrusion member inserted into the main body, and also pushes the lens out from an insertion part disposed at the tip side of the main body and inserted into the eye in a compact folded state, wherein a part of the outer circumferential surface of the extrusion member has a protrusion that extends from the outer circumferential surface in a direction intersecting the axial direction of the extrusion shaft, and when the extrusion member moves along a passage along the extrusion shaft inside the main body, if a stress due to the folding of the intraocular lens acts on the extrusion member that causes the extrusion member to deviate from the intended trajectory, the protrusion contacts a part of the passage of the main body before the outer circumferential surface, and functions as a counter mechanism to exert a stress on the extrusion member that returns the extrusion member to the intended trajectory.

[0009] The intraocular lens insertion device of this disclosure provides an intraocular lens insertion device that suppresses unintended axial misalignment of the extrusion member in the plunger caused by stress associated with the folding of the intraocular lens. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view of the intraocular lens insertion device of this embodiment, viewed from an oblique angle above. [Figure 2] This is a perspective view of the intraocular lens insertion device of this embodiment, viewed from diagonally below. [Figure 3] Figure 1 shows a left side view of the intraocular lens insertion device, with (a) showing it during insertion and (b) showing it in storage. [Figure 4] This is an exploded perspective view of the intraocular lens insertion device of this embodiment. [Figure 5] This is a plan view of the intraocular lens in this embodiment. [Figure 6] This is a right side view of the intraocular lens in this embodiment. [Figure 7] This is a partial perspective view of the plunger's extrusion member, seen from a diagonal downward angle. [Figure 8] This is an enlarged partial perspective view of section VIII in Figure 7. [Figure 9] This is a perspective view of the set section of the intraocular lens insertion device of this embodiment, viewed from diagonally above. [Figure 10] This is a perspective view of the top plate portion of the intraocular lens insertion device of this embodiment, viewed from diagonally below. [Figure 11] This is a schematic diagram illustrating the state at which the extrusion of the intraocular lens by the extrusion member has begun. [Figure 12] This is a schematic diagram illustrating the state in which the posterior support portion of the intraocular lens is deformed and moved onto the optical portion by the extrusion member. [Figure 13] This is a schematic diagram illustrating the state in which the intraocular lens moves toward the nozzle due to the extrusion of the extrusion member. [Figure 14] This is a schematic diagram illustrating the state in which the intraocular lens begins to deform in a roll-like manner along the curved surface of the tip inside the nozzle. [Figure 15] This is a schematic diagram illustrating the state in which the intraocular lens is further deformed into a roll shape along the curved surface of the tip inside the nozzle. [Figure 16] This is the state just before tacking begins at the anterior support portion of the intraocular lens within the nozzle. [Figure 17] This is a schematic diagram illustrating the state in which the anterior support portion of the intraocular lens within the nozzle is tucked and begins to fold. [Figure 18] This is a schematic diagram illustrating the state in which the intraocular lens is folded and positioned in the standby position within the nozzle. [Modes for carrying out the invention]

[0011] <<Summary>> The intraocular lens insertion instrument exemplified in the present disclosure pushes out an intraocular lens installed in the internal space of a cylindrical main body portion from the axially rear side to the axially front side by a rod-shaped extrusion member inserted into the main body portion, and in a small-folded state, it is pushed out from an insertion portion disposed on the tip side of the main body portion and inserted into the eye. It is an intraocular lens insertion instrument that is inserted into the eye. A part of the outer peripheral surface of the extrusion member has a convex portion that protrudes from the outer peripheral surface in a direction intersecting the axial direction of the extrusion axis. When the extrusion member advances along a passage along the extrusion axis inside the main body portion, a stress associated with the folding of the intraocular lens acts on the extrusion member, causing a stress that shifts the axis of the extrusion member more than the planned travel locus. In this case, the convex portion functions as a counter mechanism for applying a stress to the extrusion member to return the extrusion member to the planned travel locus by coming into contact with a part of the passage of the main body portion ahead of the outer peripheral surface. Thereby, it is possible to provide an intraocular lens insertion instrument that suppresses an unintentional axial shift of the extrusion member in the plunger due to the stress associated with the folding of the intraocular lens.

[0012] Further, the convex portion has a first convex portion provided on the shaft base side in the longitudinal direction of the extrusion member. The first convex portion may be provided in the direction in which the stress that causes the extrusion member to shift the axis more than the planned travel locus acts as described above. The first convex portion may be configured to function as a counter mechanism by coming into contact with a part of the installation portion including the internal space in the main body portion. Thereby, it becomes a configuration that suppresses an unintentional axial shift of the extrusion member from the shaft base side, and it is possible to suppress the axial shift of the entire extrusion member. [[ID=X]]

[0013] Also, the intraocular lens includes a disc-shaped optical portion and a pair of support portions extending radially outward from the outer peripheral edge portion. A front support portion, which is one of the support portions, is disposed on the axially forward side of the optical portion. A rear support portion, which is the other support portion, is disposed on the axially rearward side of the optical portion. When passing through the insertion portion, the intraocular lens is bent onto the optical portion in a direction in which the tip portions of the front support portion and the rear support portion approach each other, and the optical portion is folded so as to wrap the front support portion and the rear support portion. The region of the first convex portion in the longitudinal direction of the extrusion member may be configured such that the counter mechanism functions from the front support portion tacking position where the folding of the front support portion onto the optical portion is started by the extrusion of the intraocular lens by the extrusion member to the standby position where the optical portion is folded so as to wrap the front support portion and the rear support portion and is ejected in front of the insertion portion in a standby state. Thereby, since the region of the first convex portion is configured such that the counter mechanism functions from the front support portion tacking position to the standby position, axial displacement can be suppressed while stress associated with the folding of the intraocular lens can occur.

[0014] Further, the convex portion has a second convex portion provided on the tip side in the longitudinal direction of the extrusion member. The second convex portion may be provided in the direction in which the stress that causes the extrusion member to be axially displaced beyond the planned travel locus acts as described above. The second convex portion may be configured to function as a counter mechanism by contacting a part of the sliding portion of the inner surface of the main body portion along which the extrusion member slides in the axial direction of the extrusion axis. Thereby, since the second convex portion is provided on the tip side in the longitudinal direction of the extrusion member, the counter mechanism can be suitably configured to function against the stress associated with the folding of the intraocular lens on the tip side, which is a position away from the axial base portion, so that axial displacement can be suppressed.

[0015] Further, it is preferable that the sliding portion is provided on the top surface, which is the inner surface of the main body portion on the side where the intraocular lens is folded. Thereby, when the sliding portion is provided on the top surface side, the design freedom of the intraocular lens insertion instrument provided with the counter mechanism is improved.

[0016] <<Embodiment>> Hereinafter, one typical embodiment of the present disclosure will be described with reference to Figures 1 to 17.

[0017] In the following explanation, the directions shown in each figure are described as follows: the direction toward the tip of the nozzle 180 side of the main body 100 of the intraocular lens insertion device 10 (lower left side of Figure 1) is the front (tip direction) of the intraocular lens insertion device 10; and the direction toward the pressing part 370 of the plunger 300 (upper right side of Figure 1) is the rear (proximal end direction) of the intraocular lens insertion device 10. Furthermore, the upper side of Figure 1 is described as above the intraocular lens insertion device 10, the lower side of Figure 1 is described as below the intraocular lens insertion device 10, the lower right side of Figure 1 is described as to the left of the intraocular lens insertion device 10, and the upper left side of Figure 1 is described as to the right of the intraocular lens insertion device 10.

[0018] <1-1. Overall Structure> The overall configuration of the intraocular lens insertion device 10 of this embodiment will be described using Figures 1 to 4. The intraocular lens insertion device 10 of this embodiment is used to deliver a deformable intraocular lens 1 (see Figures 9, 10, etc.) into the eye. In other words, the intraocular lens insertion device 10 ejects the intraocular lens 1. The intraocular lens insertion device 10 comprises, as an example, a main body 100 and a plunger 300. The main body 100 is cylindrical and has a deformation means for bending the intraocular lens 1 into a small size. The plunger 300 is rod-shaped and is used as an extrusion means to push the intraocular lens 1 into the patient's eye along the extrusion axis A.

[0019] The plunger 300 is attached to the main body 100. The plunger 300 can move forward and backward relative to the main body 100. By pushing the plunger 300 toward the tip while bringing it into contact with the intraocular lens 1 filled inside the main body 100, the intraocular lens 1 is ejected into the patient's eye.

[0020] The intraocular lens insertion device 10 of this embodiment is switchable between an insertion state, used when inserting the intraocular lens 1 into the eye, and a storage state, used when transporting and storing the intraocular lens insertion device 10. In the insertion state, the set unit 170 (details will be described later) is close to the main unit 100 (see Figure 3(a)). In the storage state, the set unit 170 is farther away from the main unit 100 (see Figure 3(b)).

[0021] The main body 100 and plunger 300 of this embodiment are formed by injection molding using a resin material (for example, polypropylene). The intraocular lens insertion device 10 may be formed by mold molding, cutting by machining resin, or other methods. By forming the intraocular lens insertion device 10 from a resin material, the intraocular lens insertion device 10 can be easily disposed of after use. By forming the intraocular lens insertion device 10 from a resin material, the manufacturing cost of the intraocular lens insertion device 10 can be reduced. In addition, the intraocular lens insertion device 10 can be provided to users at a low cost.

[0022] In this embodiment, the inner wall of the cylindrical main body 100 is coated with a lubricating coating to extrude the adhesive, flexible intraocular lens 1. The intraocular lens insertion device 10 of this embodiment is made of colorless, transparent or colorless, semi-transparent material. This allows the user to easily see the deformation state of the intraocular lens 1 filled inside the intraocular lens insertion device 10 from the outside of the device. The intraocular lens insertion device 10 of this embodiment is a so-called pre-loaded type, and is shipped with the intraocular lens 1 pre-filled. The intraocular lens insertion device 10 may also be a cartridge type with a replaceable nozzle 180.

[0023] <1-2. Main body> In this embodiment, the main body 100 includes, as an example, a main body cylinder 110, a mounting section 130, and a nozzle 180. The main body cylinder 110 is located at the base end of the main body 100. The main body cylinder 110 has a cylindrical shape that extends in the forward direction (front-back direction). The mounting section 130, into which the intraocular lens 1 is filled, is connected to the tip of the main body cylinder 110. The nozzle 180 is connected to the tip of the mounting section 130. The nozzle 180 has a tapered outer shape and an internal space. The nozzle 180 deforms the intraocular lens 1 into a small shape due to its tapered internal space. Inside the main body 100, there is a through hole that penetrates from the base end of the main body cylinder 110 to the tip of the nozzle 180.

[0024] The main body 100 of this embodiment is manufactured by joining multiple components. More specifically, the main body cylinder 110, left and right wall sections 140, storage section 160, and nozzle 180 are integrally molded into a single component, to which the set section 170 and top plate section 150, which are separate components, are joined. Each component will be described later.

[0025] <1-3. Main body cylinder section> The main cylindrical portion 110 includes, as an example, a protruding portion 111, a front engaging portion 112, a rear engaging portion 113, and a front inclined portion 114. The main cylindrical portion 110 has a substantially rectangular cross-sectional shape. A protruding portion 111 for the user to grip with their fingers is connected to the outer wall of the main cylindrical portion 110, slightly towards the tip from the base end. The protruding portion 111 is a plate-shaped member and protrudes from the outer wall of the main cylindrical portion 110 in a direction substantially perpendicular to the extrusion shaft A.

[0026] The main cylindrical portion 110 is provided with a front engaging portion 112 and a rear engaging portion 113 on its outer wall on the bottom side (see Figure 2). The rear engaging portion 113 is formed between the base end and the protruding portion 111 of the main cylindrical portion 110. The rear engaging portion 113 is a hole for engaging with the front vane portion 351 of the plunger 300 (described later with reference to Figure 4). The front engaging portion 112 is formed between the tip of the main cylindrical portion 110 and the protruding portion 111. The front engaging portion 112 has a hole with the same opening area as the hole in the rear engaging portion 113. The front engaging portion 112 is a hole for engaging with the front vane portion 351 of the plunger 300 (described later with reference to Figure 4), similar to the rear engaging portion 113.

[0027] A forward-sloping portion 114 is formed at the tip of the lower outer wall of the main cylindrical portion 110. The forward-sloping portion 114 is formed by inclining the wall portion forming the main cylindrical portion 110 forward. When the main cylindrical portion 110 is viewed from the direction of the tip and base end, the hollow area is smaller at the tip than at the base end due to the forward-sloping portion 114. The forward-sloping portion 114 acts as a means of restricting the movement of the plunger 300. The movement of the plunger 300 is stopped when the forward-sloping portion 114 comes into contact with the inclined surface 353 (see Figure 4) provided approximately at the center of the plunger 300 in the front-rear direction.

[0028] <1-4. Installation section> The installation section 130 includes, as an example, left and right wall sections 140, a top plate section 150, a storage section 160, and a set section 170 (see Figures 1 to 4). The left and right wall sections 140 are connected to the tip of the main body cylindrical section 110. The left and right wall sections 140 have a right wall and a left wall. The right wall extends from the right end of the tip of the main body cylindrical section 110 toward the tip. The left wall extends from the left end of the tip of the main body cylindrical section 110 toward the tip. The right wall and the left wall are parallel to each other and perpendicular to the horizontal plane containing the extrusion axis A. The distance between the right wall and the left wall is shorter than the maximum outer diameter of the intraocular lens 1 and slightly longer than the diameter of the optical section 2 of the intraocular lens 1.

[0029] <1-5. Top Panel> The top plate portion 150 is a substantially flat plate-shaped member, as shown in Figure 5. The top plate portion 150 is connected to the upper tip of the main body cylindrical portion 110, the upper ends of the left and right wall portions 140, and the upper base end of the nozzle 180 (details will be described later) (see Figures 1 and 4). The top plate portion 150 is positioned across the nozzle 180 and the mounting portion 130 and is a cover member that covers their upper openings. The top plate portion 150 may be formed by injection molding using a resin material (for example, polypropylene), cutting by machining the resin, etc. The top plate portion 150 is flat and is formed to cover the openings of the nozzle 180 and the mounting portion 130. The upper opening of the extrusion shaft A, formed by the main body cylindrical portion 110, the left and right wall portions 140, and the nozzle 180, is closed by the top plate portion 150. The side of the top plate portion 150 facing the direction of the extrusion shaft A (the side facing the surface 2A of the optical portion 2 that is filled into the intraocular lens insertion device 10) becomes the inner wall surface (inner surface) that forms the cylindrical main body portion 100. The other side becomes the outer wall surface (outer surface) of the main body portion 100.

[0030] The inner wall surface of the top plate portion 150 is provided with, for example, an axial groove 152 (sliding portion) (see Figure 5). In Figure 5, a mesh-like pattern is added to clearly show the axial groove 152. The axial groove 152 is provided on the inner wall surface of the top plate portion 150 to suppress axial misalignment of the tip portion 310 and the extruded member 330 (see Figure 4) as they advance towards the tip inside the main body portion 100. The axial groove 152 is formed in a groove shape by curving the inner wall surface of the top plate portion 150 upward. The axial groove 152 is formed in a curved shape corresponding to the cross-sectional shape of the extruded member 330 (see Figure 4). The axial groove 152 is formed to extend in the front-rear direction along the extrusion shaft A, through the central part of the inner wall surface of the top plate portion 150. In other words, the shaft groove 152 (sliding portion) functions as a means to suppress shaft misalignment in the direction of the tip of the extrusion member 330 in the plunger 300 that moves in the direction of the tip. Furthermore, a contact portion 154 is provided on the right side of the shaft groove 152, towards the front. Specifically, the contact portion 154 is formed in a configuration such that the tip portion 310 is pushed out toward the tip, the tip-side convex portion 324 (second convex portion) passes the front end of the installation portion 130 (enters the inner surface of the nozzle 180), and the front vane portion 351 of the plunger 300 engages with the front engaging portion 112 of the main body cylinder portion 110 (standby position). Furthermore, forward of the contact portion 154, a right side wall 155 is formed that maintains a position where the tip-side convex portion 324 (second convex portion) contacts the front end of the top plate portion 150. In Figure 5, the contact portion 154 and the right side wall 155 are shown with a mesh-like pattern to clearly represent them. The contact portion 154 functions as a counter mechanism by contacting (working together with) the tip-side protrusion 324 (second protrusion), which will be described later. The function of the counter mechanism between the contact portion 154 and the tip-side protrusion 324 (second protrusion) will be described later. The tip-side protrusion 324 (second protrusion) functions as a counter mechanism by continuing to contact the right side wall 155 even after passing the contact portion 154. The function of the counter mechanism between the right side wall 155 and the tip-side protrusion 324 (second protrusion) will be described later.

[0031] <1-6.Storage Department> As shown in Figures 1 to 4, the storage section 160, for example, holds the intraocular lens 1 while the intraocular lens insertion device 10 is in storage. The storage section 160 is connected to the lower ends of the left and right wall sections 140. The storage section 160 is formed, for example, on a roughly plate-shaped base. This base has through holes that allow the axial support section 172 and the distortion section 174 of the set section 170, which will be described later, to move vertically through. In this embodiment, the intraocular lens storage section 160 contacts the bottom side (back surface 2B) of the optical section 2 of the intraocular lens 1 when it is in storage, and holds the intraocular lens 1.

[0032] <1-7. Set Section> As shown in Figure 6, the setting section 170 moves the intraocular lens 1 held in the storage section 160 to a setting position where it can be pushed out by the tip section 310, thereby positioning the intraocular lens 1 in the setting position. When the intraocular lens 1 is positioned in the setting position, the optical section 2 of the intraocular lens 1 is placed in the installation section 130 (see Figures 1 to 4). When the tip section 310 is pushed out towards the tip, the intraocular lens 1 passes through the installation section 130 and moves to the tip section 181, and is discharged into the eye from the bevel section 183 of the nozzle 180 (see Figure 1). The width of the inner wall forming the installation section 130 in the left-right direction (perpendicular to the extrusion axis A and parallel to the optical surface of the optical section 2) is formed to be greater than or equal to the left-right width of the optical section 2 (in this embodiment, the diameter of the optical section 2). The tip section 181 has an inner wall that tapers towards the tip. In other words, the cross-sectional area of ​​the tip section 181 in the direction perpendicular to the extrusion shaft A decreases as it approaches the tip. The optical section 2 is ejected from the bevel section 183 in a bent state due to the tip section 181.

[0033] As shown in Figure 6, the set portion 170 of this embodiment includes, as an example, a base portion 171, a shaft support portion 172, a bending portion 174, a guide portion 178, and a pivot portion 167. The base portion 171 is a plate-shaped member and has an inner wall surface facing the storage portion 160 (see Figures 1-3) and an outer wall surface facing outward (downward). The shaft support portion 172 is formed slightly towards the tip from the base end of the inner wall surface of the set portion 170. The shaft support portion 172 is formed by two arms projecting upward from the base portion 171, with a right arm portion 172R and a left arm portion 172L branching into two in the left-right direction. The distance between the left and right inner surfaces where the two right arm portions 172R and left arm portion 172L of the shaft support portion 172 face each other is formed with an opening diameter that allows the extrusion member 330 to pass through. In other words, the shaft support portion 172 functions as an axial misalignment suppression means that suppresses axial misalignment of the extrusion member 330 moving toward the tip of the plunger 300 by supporting the extrusion member 330 from the left and right directions with two right arm portions 172R and left arm portion 172L. The distorted portion 174 is formed as a passage wall facing one of the optical surfaces of the optical portion 2 (in this embodiment, the back surface 2B of the intraocular lens 1). When viewed from the tip direction of the extrusion shaft A, the distorted portion 174 is distorted in a concave shape toward the direction away from the extrusion shaft A (downward in this embodiment). A recessed groove guide portion 178 is provided on the surface of the distorted portion 174. The pivot portion 167 is a projection-like member that protrudes further toward the tip from the tip end of the base portion 171. The pivot portion 167 fits into a groove or hole provided near the tip of the installation portion 130 with an appropriate gap. The base portion 171 can rotate relative to the main body portion 100 around a rotation axis that crosses the pivot point portion 167 in the left-right direction. Furthermore, the right arm portion 172R of the shaft support portion 172 functions as a counter mechanism by contacting (working together with) the base end protrusion 334 (first protrusion), which will be described later. The function of the counter mechanism between the right arm portion 172R and the base end protrusion 334 (first protrusion) will be described later.

[0034] As shown in Figure 6, the guide portion 178 is a groove formed by recessing the surface of the distorted portion 174. In Figure 6, the guide portion 178 is shown with a mesh-like pattern to clearly represent it. The guide portion 178 extends in the axial direction (front-back direction) along the extrusion shaft A. The guide portion 178 supports the plunger 300 from the side to prevent the plunger 300 from shifting in the left-right direction along the extrusion shaft A as the plunger 300 moves along the extrusion shaft A. In other words, the guide portion 178 functions as an axial misalignment suppression means to suppress axial misalignment when the extruded member 330 moves in the tip direction along the plunger 300 as it moves in the tip direction.

[0035] <1-8. Nozzle> Next, the nozzle 180 will be described. The nozzle 180 comprises a tip section 181 and an insertion section 182 (see Figures 1 and 2, etc.). The rear end of the nozzle 180 is connected to the tip of the installation section 130. As mentioned above, the tip section 181 is formed in a shape that tapers towards the tip. The cross-sectional shape of the tip section 181 is approximately elliptical. Due to the tapered shape, the distance between the extrusion shaft A and the inner wall becomes shorter towards the tip. The insertion section 182 is connected to the tip of the tip section 181.

[0036] The cross-sectional shape of the insertion portion 182 is approximately circular. A bevel portion 183 is formed on the tip side of the insertion portion 182. The bevel portion 183 forms an opening that is inclined to the left with respect to a plane perpendicular to the extrusion shaft A. The opening of the insertion portion 182 is formed with an opening diameter that allows the tip portion 310 of the plunger 300 and the extrusion member 330 to pass through. In this embodiment, the bevel portion 183 is formed by cutting the base end of the opening end face that forms the bevel portion 183 in the direction of the base end of the extrusion shaft A. By cutting the base end shape of the bevel portion 183 in the direction of the base end, the outer diameter of the cross-sectional shape of the insertion portion 182 can be deformed to a smaller size when inserting the insertion portion 182 into the incision of the patient's eye. Therefore, the user (e.g., surgeon) can easily insert the insertion portion 182 into the incision of the patient's eye.

[0037] <2. Plunger> Next, the plunger 300 of this embodiment will be described using Figure 4. The plunger 300 is a component that moves the intraocular lens 1, which is placed in the mounting section 130, in order to insert it into the patient's eye. The plunger 300 of this embodiment is also a component that moves the support section 3 of the intraocular lens 1 toward the optical section 2. As an example, the plunger 300 of this embodiment includes an extrusion member 330, a shaft base 350, and a pressing section 370.

[0038] The pressing portion 370 will now be described. A pressing portion 370 is formed at the base end of the plunger 300. The pressing portion 370 is a plate-shaped member that extends in a direction perpendicular to the extrusion shaft A. When viewed from the base end side of the extrusion shaft A, the pressing portion 370 is formed in a convex shape with its lower end protruding downwards. The user's fingers come into contact with the pressing portion 370 when the user pushes out the plunger 300.

[0039] The shaft base 350 will now be described. The shaft base 350 is connected to the tip side of the pressing portion 370. The shaft base 350 is a rod-shaped member that extends in the direction of the tip (front-rear direction) of the extrusion shaft A. The shaft base 350 is formed with a substantially H-shaped cross-section. The shaft base 350 includes a front wing portion 351 and a rear wing portion 352. The front wing portion 351 and the rear wing portion 352 are formed in a wing shape and are formed on the bottom side of the shaft base 350. The front wing portion 351 is provided on the tip side of the shaft base 350, and the rear wing portion 352 is provided on the base end side of the shaft base 350.

[0040] The plunger 300 is locked to the main body 100 by the engagement of the front wing portion 351 with the front engaging portion 112 or the rear engaging portion 113 (see Figure 2). Furthermore, the plunger 300 is positioned and its backward movement is prevented. In the intraocular lens insertion device 10 of this embodiment, the position of the plunger 300 when the rear engaging portion 113 and the front wing portion 351 are engaged becomes the extrusion start position where the forward pushing of the intraocular lens 1 begins. Similarly, the position of the plunger 300 when the front engaging portion 112 and the front wing portion 351 are engaged becomes the standby position where the insertion of the intraocular lens 1 into the patient's eye begins.

[0041] At the extrusion start position, the tip 310 of the plunger 300 is positioned slightly towards the tip of the base end of the mounting section 130. At the standby position, the tip 310 of the plunger 300 is positioned approximately midway along the length of the nozzle 180. At the extrusion start position, the plunger 300 is not in contact with the intraocular lens 1 filled in the mounting section 130. By inserting the shaft base 350, which has a roughly H-shaped cross-section, into the main body 100, which has a roughly rectangular cross-section, circumferential rotation of the extrusion shaft A of the plunger 300 relative to the main body 100 is suppressed.

[0042] The extrusion member 330 will now be described. As shown in Figure 7, the extrusion member 330 is connected to the tip of the shaft base 350. The extrusion member 330 in this embodiment is a rod-shaped member that extends in the axial direction of the extrusion shaft A, and its overall cross-sectional shape is substantially circular. In the intermediate portion of the extrusion member 330 from the shaft base 350 (see Figure 4) to the tip 310, a columnar cylindrical portion 332 is formed toward the tip 310, with a cross-sectional shape perpendicular to the extrusion shaft A being substantially circular. The length of the shaft base 350 is substantially the same as the length from the base end of the installation portion 130 to the tip of the nozzle 180. The extrusion member 330 is formed to be thick enough to pass through the opening of the insertion portion 182 at the tip of the main body portion 100. A part of the outer circumferential surface of the cylindrical portion 332 of the extrusion member 330 has a base-side convex portion 334 (first convex portion) which is a convex portion that protrudes from the outer circumferential surface in a direction intersecting the axial direction of the extrusion shaft A (outward). In Figure 7, the base-side protrusion 334 (first protrusion) is shown with a mesh-like pattern to clearly represent it. The base-side protrusion 334 (first protrusion) is a part that functions as a counter mechanism by contacting (working together with) the right arm portion 172R of the shaft support portion 172. The function of the counter mechanism between the base-side protrusion 334 (first protrusion) and the right arm portion 172R will be described later.

[0043] The tip portion 310 will now be described. As shown in Figures 7 and 8, the extrusion member 330 has a tip portion 310 at its tip. The tip portion 310 is connected to the tip of the extrusion member 330. The tip portion 310 is formed to be wide enough to pass through the opening of the insertion portion 182 at the tip of the main body portion 100. In other words, the cross-sectional area of ​​the tip portion 310 in the direction perpendicular to the extrusion shaft A is formed to be wide enough to pass through the insertion portion 182. The tip portion 310 has an upper guide surface 312, a lower guide surface 314, a first extrusion portion 316, and a second extrusion portion 318. The tip portion 310 also has a shape in which both the left and right sides are cut out in the vertical direction (up and down direction). On the right side surface 320, a rib 322 is provided along the direction of the extrusion shaft A at an intermediate position in the vertical direction. A tip-side protrusion 324 (second protrusion) is provided on the tip side of the rib 322. The tip-side protrusion 324 (second protrusion) protrudes upward from the rib 322. Furthermore, the tip-side protrusion 324 (second protrusion) extends to the right, similar to the rib 322. In other words, a portion of the outer circumferential surface of the tip portion 310 of the extruded member 330 has a tip-side protrusion 324 (second protrusion) that extends from the outer circumferential surface in a direction intersecting the axial direction of the extrusion shaft A (outward). The tip-side protrusion 324 (second protrusion) functions as a counter mechanism by contacting (working with) the contact portion 154. The function of the counter mechanism between the tip-side protrusion 324 (second protrusion) and the contact portion 154 will be described later.

[0044] The upper guide surface 312 is the upper guide surface of the tip portion 310 and is configured in a shape that retains a portion of the columnar outer surface of the cylindrical portion 332. The upper guide surface 312 guides the top side of the insertion portion 182. The lower guide surface 314 is the lower guide surface of the tip portion 310 and is configured in a shape that retains a portion of the columnar outer surface of the cylindrical portion 332. The lower guide surface 314 guides the sliding surface side of the inner surface of the insertion portion 182 that is opposite to the top surface in the vertical direction.

[0045] The first extrusion portion 316 is the portion that pushes the posterior support portion 3B of the intraocular lens 1 forward in the direction of the central axis (extrusion axis A). The first extrusion portion 316 is the end face of approximately the upper half of the end face of the tip portion 310 and has a surface perpendicular to the central axis (extrusion axis A). The upper guide surface 312 has an upper flange portion 312A that protrudes forward in a flange shape from the first extrusion portion 316 and functions to prevent the posterior support portion 3B from deviating upward when it is pushed out. In addition, the right side surface of the first extrusion portion 316 has a tapered portion 317 that narrows towards the tip. In addition, the left side surface of the first extrusion portion 316 has a chamfered portion 319 at the tip. Comparing the inclination angles of the tapered portion 317 on the right side of the first extrusion portion 316 and the chamfered portion 319 on the left side of the first extrusion portion 316 with respect to the extrusion axis A, the chamfered portion 319 has a larger inclination angle than the tapered portion 317.

[0046] The second extrusion portion 318 is the portion that extrudes the outer peripheral edge portion 2C of the optical portion 2 in the intraocular lens 1 toward the front side (axial forward side) in the direction of the central axis (extrusion axis A). The second extrusion portion 318 is the end face of the approximately lower half of the end face of the tip portion 310 and has a surface perpendicular to the central axis (extrusion axis A). The downward guide surface 314 has a downward flange portion 314A that protrudes forward in a flange shape from the second extrusion portion 318 and functions to prevent the optical portion 2 from deviating downward when it is extruded. The first extrusion portion 316 described above is located axially forward of the second extrusion portion 318.

[0047] <3. Intraocular Lens> Referring to Figures 9 and 10, an example of an intraocular lens 1 inserted into the eye by an intraocular lens insertion device 10 will be described. The intraocular lens 1 comprises an optical part 2 and a support part 3. The intraocular lens 1 in this embodiment is a so-called one-piece type intraocular lens in which the optical part 2 and the support part 3 are integrally molded. In the intraocular lens 1 used in this embodiment, the optical part 2 and a pair of support parts 3, namely an anterior support part 3A and a posterior support part 3B, are integrally molded. As the material of the flexible material, the intraocular lens 1 can be made of various flexible resin materials, such as BA (butyl acrylate), HEMA (hydroxyethyl methacrylate), or composite materials of acrylic acid ester and methacrylic acid ester. Although a so-called one-piece type intraocular lens 1 is exemplified in this embodiment, at least a part of the technology exemplified in this disclosure can also be applied to a so-called three-piece type intraocular lens in which the optical part 2 and the support part 3 are formed from separate components.

[0048] The optical unit 2 provides a predetermined refractive power to the patient's eye. The optical unit 2 is disc-shaped. The optical axis L of the optical unit 2 passes through the center of the optical unit 2 and extends in the vertical direction. The optical unit 2 has a surface 2A that faces the top plate portion 150 of the mounting portion 130 as described later, and a back surface 2B formed on the opposite side of surface 2A, as end faces in the direction of the optical axis L. The support portion 3 supports the optical unit 2 within the eye. As an example, the intraocular lens 1 of this embodiment is provided with a pair of support portions 3, namely an anterior support portion 3A and a posterior support portion 3B. The anterior support portion 3A and the posterior support portion 3B extend radially outward from the outer peripheral edge portion 2C of the optical unit 2 and are formed in point-symmetric positions with respect to the optical axis L, which is the center of the optical unit 2. The anterior support portion 3A has a base portion 6A connected to the outer peripheral edge portion 2C of the optical unit 2 via a connecting portion 4A, and is a loop shape that is curved in the circumferential direction, with an open tip portion 8A. (That is, the tip portion 8A is considered a free end). The rear support portion 3B has a base portion 6B connected to the outer peripheral edge portion 2C of the optical portion 2 via a connecting portion 4B, and is a loop shape that is curved in the circumferential direction, with the tip portion 8B open (that is, the tip portion 8B is considered a free end). The front support portion 3A is located within the main body portion 100 on the bevel portion 183 side of the optical portion 2. The rear support portion 3B is located within the main body portion 100 on the rear side of the optical portion 2 (the side away from the bevel portion 183). The outer peripheral edge portion 2C is also referred to as the "edge".

[0049] <4. Counter mechanism> The counter mechanism in the intraocular lens insertion device 10 of this embodiment will now be described.

[0050] As described above, the extrusion member 330 has its axial misalignment suppressed when moving towards the tip by the shaft groove 152 (sliding part) on the inner wall surface of the top plate part 150 shown in Figure 5, and the shaft support part 172 and guide part 178 in the set part 170 shown in Figure 6 (axial misalignment suppression means). Here, the trajectory in which the extrusion member 330 advances (is guided) in the intended tip direction by the axial misalignment suppression means of the shaft groove 152 (sliding part), shaft support part 172 and guide part 178 is the intended advancement trajectory. However, the above-described axial misalignment suppression means requires further improvement when unintended axial misalignment of the extrusion member 330 occurs due to stress associated with the folding of the intraocular lens 1, and attempts to displace in the axial misalignment direction beyond the intended advancement trajectory. Here, the occurrence of unintended axial misalignment of the extrusion member 330 due to stress associated with the folding of the intraocular lens 1 is more pronounced when the anterior support part 3A of the intraocular lens 1 inside the nozzle 180 begins to tuck. Therefore, the intraocular lens insertion device 10 of this embodiment has a counter mechanism.

[0051] The counter mechanism is a mechanism that, when the extruder member 330 is moving along a passage along the extrusion axis A inside the main body 100, and the stress associated with the folding of the intraocular lens 1 is exerted on the extruder member 330, causing it to be displaced in the axial misalignment direction beyond the planned trajectory, contacts a part of the passage in the main body 100 with the outer surface of the extruder member 330 before it can move, thereby applying a stress to the extruder member 330 that returns it to the planned trajectory in response to the stress associated with the folding of the intraocular lens 1.

[0052] A portion of the outer circumferential surface of the extruded member 330 has a base-side protrusion 334 (first protrusion) and a tip-side protrusion 324 (second protrusion) that extend from the outer circumferential surface in a direction intersecting the axial direction of the extruded shaft A (outward). The base-side protrusion 334 (first protrusion) functions as a counter mechanism by contacting (cooperating with) the right arm portion 172R of the shaft support portion 172. The tip-side protrusion 324 (second protrusion) also functions as a counter mechanism by contacting (cooperating with) the contact portion 154.

[0053] <4-1. Protruding part on the base side (first protrusion)>The proximal end protrusion 334 (first protrusion) is provided on the shaft base 350 side in the longitudinal direction of the extrusion member 330. The proximal end protrusion 334 (first protrusion) protrudes from the outer circumferential surface in a direction (360°) that intersects with the axial direction of the extrusion shaft A, on a part of the outer circumferential surface of the cylindrical portion 332 of the extrusion member 330. The proximal end protrusion 334 (first protrusion) is provided in a direction in which stress associated with the folding of the intraocular lens 1 causes the extrusion member 330 to deviate from its axial direction beyond the planned trajectory (it is provided in a direction in which unintended axial deviation of the extrusion member 330 may occur), thereby acting as a counter mechanism to return to the planned trajectory. The proximal end protrusion 334 (first protrusion) is in contact with the set portion 170, which is part of the installation portion having an internal space in the main body portion 100. In detail, the proximal protrusion 334 (first protrusion) contacts (cooperates with) the right arm portion 172R of the shaft support portion 172 of the set portion 170. The circumferential position where the proximal protrusion 334 (first protrusion) is located is on the outer circumferential surface of the cylindrical portion 332 of the extrusion member 330, at a position facing the right arm portion 172R, and is formed to protrude from the outer circumferential surface in a direction intersecting the axial direction of the extrusion shaft A (outward). This is because the direction in which unintended axial misalignment of the extrusion member 330 may occur due to stress associated with the folding of the intraocular lens 1 is to the right of the extrusion member 330 (see σa and σb in Figures 17 and 18), and therefore it is located at a position facing the right arm portion 172R which is located in that direction. Furthermore, the longitudinal length of the proximal convex portion 334 (first convex portion) is formed on the outer circumferential surface of the cylindrical portion 332 of the extrusion member 330, between the anterior support portion tacking position and the standby position of the intraocular lens 1. Here, the anterior support portion tacking position is the position in which the extrusion of the intraocular lens 1 by the extrusion member 330 causes the base portion 6A of the anterior support portion 3A to be bent backward within the nozzle 180, and the anterior support portion 3A deforms and moves onto the surface 2A of the optical portion 2, beginning the folding process. The standby position is the position in which the extrusion of the intraocular lens 1 by the extrusion member 330 causes the optical portion 2 to fold within the nozzle 180 so as to enclose the anterior support portion 3A and the posterior support portion 3B, and the lens waits to be ejected in front of the insertion portion 182.Specifically, the standby position is the position where the front vane portion 351 of the plunger 300 engages with the front engaging portion 112 of the main body cylindrical portion 110.

[0054] <4-2. Protruding tip portion 324 (second protruding portion)> The tip-side protrusion 324 (second protrusion) is provided on the tip portion 310 on the longitudinal side of the extrusion member 330. The tip-side protrusion 324 (second protrusion) contacts (cooperates with) the contact portion 154, which is part of the shaft-out groove 152 (sliding portion) on the inner surface of the main body portion 100, on which the extrusion member 330 slides along the axial direction of the extrusion shaft A. The shaft-out groove 152 (sliding portion) is provided on the top surface side of the inner surface of the main body portion 100, which is the inner surface on which the intraocular lens 1 is folded. The contact portion 154 is provided on the right side of the shaft-out groove 152, and is located towards the front. Specifically, the contact portion 154 is formed in such a configuration that the tip portion 310 is pushed outwards, causing the tip-side protrusion 324 (second protrusion) to pass the front end of the mounting portion 130 (entering the inner surface of the nozzle 180), and the forward wing portion 351 of the plunger 300 engages with the front engaging portion 112 of the main body cylinder portion 110 (standby position). The contact portion 154 is provided at a position where the tip-side protrusion 324 (second protrusion) makes contact when the intraocular lens 1 reaches the tacking position of the front support portion. Furthermore, forward of the contact portion 154, a right-side wall 155 is formed up to the front end of the top plate portion 150, maintaining a position where the tip-side protrusion 324 (second protrusion) makes contact. Therefore, even after the tip-side protrusion 324 (second protrusion) passes the contact portion 154, it continues to contact the right-side wall 155, functioning as a counter mechanism. In other words, the tip-side protrusion 324 (second protrusion) is positioned in a direction that causes stress associated with the folding of the intraocular lens 1 to misalign the extrusion member 330 beyond the planned trajectory (positioned in a direction that may cause unintended misalignment of the extrusion member 330), thereby acting as a counter mechanism to return to the planned trajectory.

[0055] <5. Effect> Referring to Figures 11-18, the operation of the intraocular lens insertion device 10 of this embodiment as illustrated in this disclosure will be described.

[0056] First, the user positions the intraocular lens 1, held in the mounting section 130, at the extrusion start position of the intraocular lens 1, where the front vane portion 351 of the plunger 300 engages with the rear engaging portion 113 of the main body cylinder 110. The extrusion start position is the position from which the intraocular lens 1 can be pushed out by the plunger 300. At the extrusion start position, the tip portion 310 of the plunger 300 is located slightly towards the tip from the base end of the mounting section 130. At the extrusion start position, the plunger 300 is not in contact with the intraocular lens 1 filled in the mounting section 130. The insertion of the shaft base portion 350, which has a roughly H-shaped cross-section, into the main body portion 100, which has a roughly rectangular cross-section, suppresses the circumferential rotation of the extrusion shaft A of the plunger 300 relative to the main body portion 100.

[0057] As shown in Figure 11, the intraocular lens 1 installed in the mounting section 130 has the base portion 6A of the anterior support section 3A positioned to the right (upper side in Figure 11) relative to the extrusion shaft A, and the base portion 6B of the posterior support section 3B positioned to the left (lower side in Figure 11) relative to the extrusion shaft A. The intraocular lens insertion device 10 in this embodiment is a so-called preset type device in which the intraocular lens 1 is pre-filled inside. However, the technology illustrated in this disclosure can also be applied to intraocular lens insertion devices in which the intraocular lens 1 is filled inside immediately before insertion into the patient's eye.

[0058] The user injects a filler (e.g., viscoelastic substance, ophthalmic irrigation solution, etc.) into the installation section 130 using an injector, and starts the forward movement of the plunger 300. As a result, as shown in Figure 11, the extrusion member 330 of the plunger 300 comes into contact with a part of the posterior support section 3B of the intraocular lens 1. That is, the first extrusion section 316 (see Figure 8) begins to extrude the posterior support section 3B. Here, the tip 310 of the extrusion member 330 is supported by passing between the left and right inner surfaces where the two right arms 172R and left arm 172L of the axial support section 172 face each other, and the extrusion member 330 follows a trajectory (planned trajectory) that propagates (is guided) in the planned direction of the tip. Therefore, the extrusion member 330 does not displace beyond the planned trajectory in the direction of axial misalignment due to stress associated with the folding of the intraocular lens 1, and does not experience unintended axial misalignment.

[0059] As shown in Figure 12, as the plunger 300 is pushed further forward, the rear support portion 3B moves towards the optical portion 2 (i.e., forward) by the extrusion member 330. Subsequently, the rear support portion 3B deforms and folds onto the surface 2A of the optical portion 2 (towards the viewer in Figure 12), and the tip portion 8B of the rear support portion 3B faces forward. As a result, tacking of the rear support portion 3B occurs. At the same time, the second extrusion portion 318 (see Figure 8) begins to extrude the outer peripheral edge portion 2C of the optical portion 2 in the intraocular lens 1 toward the front side in the direction of the central axis (extrusion axis A) (axially forward side). Here, the tip portion 310 of the extrusion member 330 extrudes the rear support portion 3B and the outer peripheral edge portion 2C of the optical portion 2. However, the extruded member 330 is supported by passing between the two opposing inner surfaces of the right arm portion 172R and left arm portion 172L of the axial support portion 172, and the extruded member 330 follows a trajectory (planned progression trajectory) that propagates (is guided) in the direction of the planned tip. Therefore, the extruded member 330 does not experience unintended axial misalignment due to stress associated with the folding of the intraocular lens 1, and does not displace beyond the planned progression trajectory in the direction of axial misalignment.

[0060] As shown in Figure 13, as the plunger 300 is pushed further forward, the intraocular lens 1 reaches the nozzle 180 and enters the inner wall of the tapered tip section 181. The anterior support section 3A is located axially forward of the optical section 2, on the insertion section 182 side, within the tip section 181. The posterior support section 3B is located axially rearward of the optical section 2, opposite to the insertion section 182 side. Here, the tip 310 of the extrusion member 330 pushes out the posterior support section 3B and the outer peripheral edge 2C of the optical section 2, causing the intraocular lens 1 to enter the inner wall of the tip section 181. However, the extrusion member 330 is supported by passing between the left and right inner surfaces where the two right arms 172R and left arm 172L of the axial support section 172 face each other, and by passing through the guide section 178 and the axial groove 152, so that the extrusion member 330 follows a trajectory (planned trajectory) that it is guided to in the planned tip direction. Therefore, the stress associated with the folding of the intraocular lens 1 does not cause unintended axial misalignment of the extruded member 330, and it does not displace beyond the planned trajectory in the axial misalignment direction.

[0061] As shown in Figure 14, the plunger 300 is pushed further forward. Then, after the base portion 6A and tip portion 8A of the anterior support portion 3A of the intraocular lens 1 come into contact with the inner wall of the tip section 181, the optical portion 2 and the anterior support portion 3A begin to deform in a roll shape along the curved surface (approximately elliptical cross-sectional shape) of the tip section 181. At this point, the extrusion of the tip portion 310 of the extrusion member 330 causes the optical portion 2 and the anterior support portion 3A of the intraocular lens 1 to begin to deform in a roll shape along the curved surface (approximately elliptical cross-sectional shape) of the tip section 181. However, the extrusion member 330 is supported by passing between the left and right inner surfaces where the two right arms 172R and left arms 172L of the axial support portion 172 face each other, and by passing through the guide portion 178 and the axial groove 152, so the extrusion member 330 follows a trajectory (planned trajectory) that moves (is guided) in the planned direction of the tip. Therefore, the stress associated with the folding of the intraocular lens 1 does not cause unintended axial misalignment of the extruded member 330, and it does not displace beyond the planned trajectory in the axial misalignment direction.

[0062] As shown in Figure 15, the plunger 300 is pushed further forward. The intraocular lens 1 then deforms further into a roll shape, with the optical part 2 and the anterior support part 3A following the inner wall of the nozzle 180. Here, the extrusion of the tip 310 of the extrusion member 330 causes the optical part 2 and the anterior support part 3A of the intraocular lens 1 to deform into a roll shape along the curved surface (approximately elliptical cross-sectional shape) of the tip part 181. However, the extrusion member 330 is supported by passing between the left and right inner surfaces where the two right arms 172R and left arm 172L of the axial support part 172 face each other, and by passing through the guide part 178 and the axial groove 152, so that the extrusion member 330 follows a trajectory (planned trajectory) that propagates (is guided) in the planned direction of the tip. Therefore, the stress associated with the folding of the intraocular lens 1 does not cause unintended axial misalignment of the extrusion member 330, and it does not displace in the axial misalignment direction beyond the planned trajectory.

[0063] As shown in Figure 16, as the plunger 300 is pushed further forward, the optical portion 2 and the anterior support portion 3A of the intraocular lens 1 deform further into a roll shape along the inner wall of the nozzle 180. The intraocular lens 1 shown in Figure 16 is in the state just before the tacking of the anterior support portion 3A begins. The anterior support portion 3A is in contact with the inner wall of the tip portion 181 and begins to approach the optical portion 2 that has been pushed out by the extrusion member 330, but the base portion 6A of the anterior support portion 3A has not yet been bent backward. At this point, the extrusion of the tip portion 310 of the extrusion member 330 causes the optical portion 2 and the anterior support portion 3A of the intraocular lens 1 to deform into a roll shape along the curved surface (the cross-sectional shape is approximately elliptical) of the tip portion 181. However, the extruded member 330 is supported by passing between the left and right inner surfaces where the two right arm portions 172R and left arm portion 172L of the shaft support portion 172 face each other, and by passing through the guide portion 178 and the groove of the shaft exit groove 152, so that the extruded member 330 moves (is guided) along a trajectory (planned movement trajectory) in the direction of the planned tip. Therefore, the extruded member 330 does not experience unintended axial misalignment due to stress associated with the folding of the intraocular lens 1, and does not displace beyond the planned movement trajectory in the direction of axial misalignment.

[0064] As shown in Figure 17, as the plunger 300 is pushed further forward, the front support portion 3A remains on the inner wall of the tip portion 181 and begins to approach the optical portion 2 that has been pushed out by the extrusion member 330. Subsequently, within the nozzle 180, the base portion 6A of the front support portion 3A is bent backward, and the front support portion 3A deforms and moves onto the surface 2A of the optical portion 2 (towards the front in the illustration in Figure 16) and folds. As a result, tacking of the front support portion 3A occurs. That is, the intraocular lens 1 reaches the front support portion tacking position. The front support portion tacking position is the position where, due to the extrusion of the intraocular lens 1 by the extrusion member 330, the base portion 6A of the front support portion 3A is bent backward within the nozzle 180, and the front support portion 3A deforms and moves onto the surface 2A of the optical portion 2 and folds. At this time, the base portion 6A of the anterior support portion 3A of the intraocular lens 1 is bent backward, causing stresses σa and σb associated with the folding of the intraocular lens 1 to be exerted on the extrusion member 330. Consequently, unintended axial misalignment occurs in the extrusion member 330, causing it to displace in the axial misalignment direction beyond the planned propagation trajectory. Here, the counter mechanism works by contacting a part of the passage of the main body portion 100 before the outer surface of the extrusion member 330, thereby exerting stresses σ1 and σ2 (white arrows in Figure 17) on the extrusion member 330 to return it to the planned propagation trajectory, in response to the stresses σa and σb (black arrows in Figure 17) associated with the folding of the intraocular lens 1. Specifically, the proximal end convex portion 334 (first convex portion) contacts (works together with) the right arm portion 172R of the axial support portion 172 of the set portion 170, thereby exerting stress σ1 on the extrusion member 330 to return it to the planned propagation trajectory, and the counter mechanism works. Similarly, the tip-side protrusion 324 (second protrusion) contacts (cooperates with) the contact portion 154, which is part of the shaft-out groove 152 (sliding portion) on the inner surface of the main body portion 100 through which the extrusion member 330 slides along the axial direction of the extrusion shaft A. This exerts a stress σ2 on the extrusion member 330 that returns it to the planned trajectory, thereby activating the counter mechanism.

[0065] As shown in Figure 18, as the plunger 300 is pushed further forward, the intraocular lens 1 folds into a smaller size with the anterior support portion 3A and the posterior support portion 3B tucked together. Then, as the intraocular lens 1 is pushed axially forward by the extrusion member 330 within the tip section 181, the passage shape of the tip section 181 causes the tip portion 8A of the anterior support portion 3A and the tip portion 8B of the posterior support portion 3B to bend toward each other onto the optical portion 2, and the optical portion 2 folds to enclose the anterior support portion 3A and the posterior support portion 3B, moving towards the standby position. At this time, the base portion 6A of the anterior support portion 3A of the intraocular lens 1 is bent backward, so stresses σa and σb associated with the folding of the intraocular lens 1 are exerted on the extrusion member 330. Consequently, unintended axial misalignment occurs in the extrusion member 330, causing it to displace in the axial misalignment direction beyond the planned trajectory. Here, the counter mechanism works by contacting a part of the passage of the main body 100 before the outer surface of the extrusion member 330, thereby applying stresses σ1 and σ2 (white arrows in Figure 18) to the extrusion member 330 to return it to the planned trajectory, in response to stresses σa and σb (black arrows in Figure 18) associated with the folding of the intraocular lens 1. Specifically, the proximal end convex portion 334 (first convex portion) contacts (works together with) the right arm portion 172R of the axial support portion 172 of the set portion 170, thereby applying stress σ1 to the extrusion member 330 to return it to the planned trajectory, and the counter mechanism works. The counter mechanism, due to the contact (cooperation) between the proximal end convex portion 334 (first convex portion) and the right arm portion 172R, works until it reaches the standby position. Similarly, the tip-side protrusion 324 (second protrusion) contacts (works with) the right-side wall 155, which is part of the shaft-out groove 152 (sliding section) on the inner surface of the main body 100 through which the extrusion member 330 slides along the axial direction of the extrusion shaft A. This applies a stress σ2 to the extrusion member 330 that returns it to the planned trajectory, thus activating the counter mechanism. The counter mechanism, caused by the contact (cooperation) between the tip-side protrusion 324 (second protrusion) and the right-side wall 155, works until it reaches the standby position. However, depending on the user's method of use, if the extrusion speed of the intraocular lens 1 is slow, or if the extrusion is intermittent, the frictional resistance applied to the intraocular lens 1 may fluctuate, potentially causing unintended axial misalignment of the extrusion member 330 and resulting in unstable behavior of the advancing intraocular lens 1. Therefore, there is concern that rotation may easily occur when the intraocular lens is folded.However, since the contact (cooperation) between the tip-side convex portion 324 (second convex portion) and the right side wall 155 works until the standby position, the counter mechanism continues to operate until the standby position. Here, since the tip portion 310 is located far from the shaft base portion 350 of the plunger 300, if stresses σa and σb associated with the folding of the intraocular lens 1 are applied to the tip portion 310, unintended axial misalignment of the extrusion member 330 is likely to occur, and this is particularly noticeable in the tip portion 310 located near the standby position. However, even if stresses σa and σb associated with the folding of the intraocular lens 1 are applied to the tip portion 310 located near the standby position, the counter mechanism will work effectively due to the contact (cooperation) between the tip-side convex portion 324 (second convex portion) and the right side wall 155.

[0066] As described above, according to the intraocular lens insertion device 10 of the present disclosure, the proximal protrusion 334 (first protrusion) and the proximal protrusion 324 (second protrusion) are configured to function as a counter mechanism that applies stresses σ1 and σ2 to the extrusion member 330 to return it to the planned propagation trajectory in response to the stresses σa and σb associated with the folding of the intraocular lens 1. This is achieved when the extrusion member 330 moves along the passage on the extrusion axis A inside the main body 100, and the stresses σa and σb associated with the folding of the intraocular lens 1 exerted on the extrusion member 330, causing it to be displaced in the axial misalignment direction beyond the planned propagation trajectory. The proximal protrusion 334 contacts a part of the passage on the main body 100 before the outer surface, thereby counteracting the stresses σa and σb associated with the folding of the intraocular lens 1 and applying stresses σ1 and σ2 to the extrusion member 330 to return it to the planned propagation trajectory.

[0067] Furthermore, the base-side projection 334 (first projection) is provided on the shaft base 350 side in the longitudinal direction of the extrusion member 330. The base-side projection 334 (first projection) is configured to function as a counter mechanism by contacting a part of the installation portion 130 which has an internal space in the main body portion 100. This configuration suppresses unintended axial misalignment of the extrusion member 330 from the shaft base 350 side, thereby suppressing axial misalignment of the entire extrusion member 330.

[0068] Furthermore, the region of the proximal end convex portion 334 (first convex portion) in the longitudinal direction of the extrusion member 330 may be configured to function as a counter mechanism from the front support portion tacking position, where the front support portion 3A begins to fold onto the optical portion 2 due to the extrusion of the intraocular lens 1 by the extrusion member 330, to the standby position, where the optical portion 2 folds to enclose the front support portion 3A and the rear support portion 3B and waits to be ejected in front of the insertion portion. As a result, the region of the proximal end convex portion 334 (first convex portion) is configured to function as a counter mechanism from the front support portion tacking position to the standby position, thereby suppressing unintended axial misalignment of the extrusion member 330 while stresses σa and σb associated with the folding of the intraocular lens 1 may occur.

[0069] Furthermore, the extruded member 330 has a tip-side protrusion 324 (second protrusion) provided on the tip side in the longitudinal direction. The tip-side protrusion 324 (second protrusion) is configured to function as a counter mechanism by contacting a part of the shaft-out groove 152 (sliding part) on the top plate portion 150 on the inner surface of the main body portion 100, where the extruded member 330 slides along the axial direction of the extruded shaft A. As a result, because the extruded member 330 has a tip-side protrusion 324 (second protrusion) provided on the tip side in the longitudinal direction, the counter mechanism is configured to function against the stresses σa and σb associated with the folding of the intraocular lens 1 at the tip portion 310, which is located away from the shaft base portion 350, thus effectively suppressing axial misalignment.

[0070] Furthermore, the axis-aligning groove 152 (sliding portion) is provided on the top plate portion 150, which is the inner surface of the main body portion 100 on the side where the intraocular lens 1 is folded. As a result, providing the axis-aligning groove 152 (sliding portion) on the top plate portion 150 on the top surface improves the design flexibility of the intraocular lens 1 insertion device equipped with a counter mechanism.

[0071] Although embodiments of the present disclosure have been described above, the intraocular lens implantation device of the present disclosure is not limited to the embodiments described above and can be implemented in various other forms. [Explanation of Symbols]

[0072] 1. Intraocular lens 2 Optical Department 2A surface 2B back side 2C Outer edge 3 Support part 3A Front support part 4A Connection part 6A Root part 8A tip part 3B Rear support part 4B Connection section 6B Root part 8B Tip part 10. Intraocular lens insertion device 100 Main body 110 Main body cylindrical part 111 Overhang 112 Front engagement part 113 Rear engaging part 114 Front slope 130 Installation section 140 Left and right walls 150 Top plate section 152 Axle-mounting groove (sliding section) 154 Contact section (counter mechanism) 155 Right side wall (counter mechanism) 160 Storage Department 167 Pivot point 170 Sets 171 Base section 172 Axis support section (counter mechanism) 172R Right arm (counter mechanism) 172L Left arm 174 Distortion part 178 Guide Section 180 nozzles 181 Tip details 182 Insertion section 183 Bevel section 300 plungers 310 Tip 324 Protruding tip (second protrusion), (counter mechanism) 330 Extruded member 332 Cylindrical section 334 Protruding part on the base end (first protruding part), (counter mechanism) 350 shaft base 351 Front wing section 352 Rear wing section 353 Slope 370 Pressing part 312 Upper guide surface 312A Upper flange 314 Downward guide surface 316 First extrusion section 317 Tapered section 318 Second extrusion section 319 Chamfered section 322 Rib A. Extrusion shaft (central axis) L optical axis

Claims

1. An intraocular lens insertion device is used to insert an intraocular lens, which is placed in the internal space of a cylindrical main body, into the eye by pushing it out from the axial rear side to the axial front side of the main body using a rod-shaped extrusion member inserted into the main body, and also by pushing it out from an insertion part located at the tip of the main body and inserted into the eye while it is folded into a small size. A portion of the outer circumferential surface of the extruded member has a protrusion that extends from the outer circumferential surface in a direction intersecting the axial direction of the extruded shaft. When the extruded member moves along a passage parallel to the extrusion shaft inside the main body, if a stress is applied to the extruded member due to the folding of the intraocular lens, causing the extruded member to deviate from its intended trajectory beyond its intended path, An intraocular lens insertion device characterized in that the protrusion contacts a part of the passage of the main body prior to the outer circumferential surface and functions as a counter mechanism to apply stress to the extruded member to return the extruded member to the planned trajectory.

2. An intraocular lens insertion device according to claim 1, The aforementioned protrusion has a first protrusion provided on the axial base side in the longitudinal direction of the extruded member, The intraocular lens insertion device is configured such that the first protrusion contacts a part of the mounting portion having the internal space in the main body, thereby functioning as the counter mechanism.

3. An intraocular lens insertion device according to claim 2, The intraocular lens comprises a disc-shaped optical portion and a pair of support portions extending radially outward from its outer edge, with one support portion, the anterior support portion, positioned axially forward of the optical portion, and the other support portion, the posterior support portion, positioned axially backward of the optical portion, and when passing through the insertion portion, the tip portions of the anterior support portion and the posterior support portion are bent toward each other onto the optical portion, and the optical portion is folded so as to enclose the anterior support portion and the posterior support portion. The region of the first protrusion in the longitudinal direction of the extruded member is An intraocular lens insertion device in which the counter mechanism is configured to function from the front support portion tacking position, where the front support portion begins to bend onto the optical portion due to the extrusion of the intraocular lens by the extrusion member, to the standby position, where the optical portion folds to enclose the front support portion and the rear support portion and waits to be ejected in front of the insertion portion.

4. An intraocular lens insertion device according to any one of claims 1 to 3, The aforementioned protrusion has a second protrusion provided on the tip side in the longitudinal direction of the extruded member, The intraocular lens insertion device is configured such that the second protrusion contacts a part of the sliding portion on the inner surface of the main body, on which the extrusion member slides along the axial direction of the extrusion shaft, thereby functioning as the counter mechanism.

5. An intraocular lens insertion device according to claim 4, The sliding portion is an intraocular lens insertion device provided on the top surface of the main body, which is the inner surface on which the intraocular lens is folded.

Images