Intraocular lens insertion device

Abstract

To provide an intraocular lens insertion instrument which improves tacking accuracy of a rear supporting part of an intraocular lens.SOLUTION: The intraocular lens insertion instrument for inserting an intraocular lens into an eye has an inclined plane 150 (an interference part) which raises an extrusion load by applying a resistance force to the movement of a plunger 300 on the inner face of a body, until reaching an abutting position from an extrusion start position 300A. On the basis of the inclined plane 150 (the interference part), a first extrusion load F1 until a plunger tip 302 reaches the abutting position is larger than a second extrusion load until a rear supporting part 3B is folded onto an optical part 2 after the plunger tip 302 starts abutting at the abutting position. The load difference varies the extrusion speed of the plunger 300 to fold the rear supporting part 3B. The intraocular lens insertion instrument has a mechanism like this.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] Traditionally, one of the most common surgical methods for cataract surgery is to insert a foldable, soft intraocular lens into the eye instead of the crystalline lens. In some cases, the intraocular lens is inserted anterior to the crystalline lens to correct the refractive power of the eye. An intraocular lens insertion device called an injector is sometimes used to insert the intraocular lens into the eye.

[0003] This type of injector inserts an intraocular lens placed in a cylindrical body into the eye by pushing the intraocular lens from the axial rear side of the body to the axial front side with a rod-shaped plunger inserted into the body, and then pushing the lens out from the tip side of the body in a compactly folded state. Here, the intraocular lens has a disk-shaped optical section and a pair of support sections extending radially outward from the outer peripheral edge of the optical section. The intraocular lens placed in the body has one support section, the anterior support section, located axially forward of the optical section, and the other support section, the posterior support section, located axially rearward of the optical section. The body in which the intraocular lens is placed is filled with a viscoelastic substance (a lubricant such as sodium hyaluronate) injected to inject the intraocular lens. The intraocular lens is pushed out by the plunger within the body, and is compactly folded by deforming the optical section into a roll shape while tucking occurs, in which the anterior and posterior support sections are folded onto the optical section. Here, it is important that the intraocular lens be folded correctly, and various techniques relating to folding of the intraocular lens are known (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5209331 Summary of the Invention [Problem to be solved by the invention]

[0005] The posterior haptic of an intraocular lens is folded onto the optic by the plunger's contact and extrusion (tacking of the posterior haptic). The tacking of the posterior haptic, which is extruded by the plunger, is sensitive to the plunger's extrusion speed. Specifically, when the plunger's extrusion speed is slow, the force applied to the posterior haptic is small, as can be seen from the equation of motion (F = ma). Furthermore, when extruding the posterior haptic, deformation due to "creep" must be taken into consideration. Generally, "creep" refers to the phenomenon in which strain increases over time when sustained stress acts on an object. When the posterior haptic is pushed by the plunger, a fast extrusion speed reduces creep deformation, suppressing localized deformation at the plunger contact point of the posterior haptic. Conversely, a slow extrusion speed causes creep deformation at the plunger contact point of the posterior haptic, further slowing deformation upon contact with the viscoelastic material. Therefore, there is concern that the posterior haptic, when pushed by the plunger, may be folded in a bent or twisted state due to the resistance of the viscoelastic material filled in the main body. In recent years, intraocular lenses have tended to have a "softer" characteristic rather than a hard one, and therefore there is a demand for a folding mechanism for the posterior support portion that further improves the tacking accuracy of the posterior support portion.

[0006] Therefore, the present disclosure has been made to solve the above-mentioned problems, and aims to provide an intraocular lens insertion instrument that improves the tacking accuracy of the posterior support portion of an intraocular lens. [Means for solving the problem]

[0007] 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 placed in a cylindrical main body portion into an eye by pushing the intraocular lens from the axial rear side of the main body portion toward the axial front side with a rod-shaped plunger inserted into the main body portion and pushing the intraocular lens in a small folded state outward from the tip side of the main body portion, wherein the intraocular lens placed in the main body portion comprises a disk-shaped optical portion and a pair of support portions extending radially outward from an outer peripheral edge of the optical portion, one of the support portions being the front support portion is disposed axially forward of the optical portion, and the other support portion being the rear support portion is disposed axially rearward of the optical portion, The plunger has an interference portion on at least one of the inner surface of the plunger or the main body portion that applies resistance to the movement of the plunger from the extrusion start position where the plunger tip begins to extrude to the abutment position where it abuts on the rear support portion, thereby increasing the extrusion load, and based on the interference portion, a first extrusion load until the plunger tip is positioned at the abutment position is greater than a second extrusion load until the plunger tip starts to abut at the abutment position and the rear support portion is folded onto the optical portion, and a mechanism is provided that changes the extrusion speed of the plunger due to this load difference to fold the rear support portion.

[0008] According to the intraocular lens insertion device of the present disclosure, it is possible to provide an intraocular lens insertion device that improves the tacking accuracy of the posterior support portion of the intraocular lens. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is an overall perspective view showing an intraocular lens insertion instrument. [Figure 2] FIG. [Figure 3] FIG. 1 is a plan view of an intraocular lens. [Figure 4] FIG. 2 is a right side view of the intraocular lens. [Figure 5] FIG. 2 is a plan view showing an intraocular lens insertion device. [Figure 6]1 is a schematic explanatory diagram showing a state in which the tip of the plunger is positioned at an extrusion start position where extrusion can begin in the intraocular lens insertion device according to the first embodiment. FIG. [Figure 7] 1 is a schematic explanatory diagram showing an actuation state in which the tip of the plunger is pushed out from the contact position where it contacts the rear support part of the intraocular lens and tacks in the intraocular lens insertion device according to the first embodiment. FIG. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 6. [Figure 9] 1 is a schematic explanatory diagram showing an intraocular lens in an installation section and a graph of changes in the pushing load at the tip of a plunger superimposed on each other in the intraocular lens insertion device according to the first embodiment. FIG. [Figure 10] FIG. 10 is a schematic explanatory diagram showing a state in which the tip of the plunger is positioned at an extrusion start position where extrusion can begin in the intraocular lens insertion device according to the second embodiment. [Figure 11] 10 is a schematic explanatory diagram showing an actuation state in which the tip of the plunger is pushed out from the contact position where it contacts the rear support part of the intraocular lens and tacks in the intraocular lens insertion device according to the second embodiment. FIG. [Figure 12] FIG. 11 is a schematic explanatory diagram showing a state in which the tip of the plunger is positioned at an extrusion start position where extrusion can begin in the intraocular lens insertion device according to the third embodiment. [Figure 13] FIG. 10 is a schematic explanatory diagram showing an actuation state in which the tip of the plunger is pushed out from the contact position where it contacts the rear support part of the intraocular lens and tacks in the intraocular lens insertion device according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] <Summary> The intraocular lens insertion device exemplified in the present disclosure inserts an intraocular lens placed in a cylindrical main body into the eye by pushing the intraocular lens from the axial rear side of the main body to the axial front side with a rod-shaped plunger inserted into the main body, and then pushing the lens out from the distal end of the main body in a compact folded state. The intraocular lens placed in the main body includes a disk-shaped optical section and a pair of support sections extending radially outward from the outer peripheral edge of the optical section. The intraocular lens placed in the main body has one support section, the anterior support section, disposed axially forward of the optical section, and the other support section, the posterior support section, disposed axially rearward of the optical section. At least one of the plunger or the inner surface of the main body has an interference section that applies resistance to plunger movement and increases the push-out load from the push-out start position where the plunger tip begins to push out to the abutment position where it abuts the posterior support section. Based on this interference portion, the first pushing load until the plunger tip reaches the contact position is greater than the second pushing load until the plunger tip starts to contact the contact position and the posterior support part is folded onto the optical part, and the mechanism for folding the posterior support part by changing the plunger pushing speed based on this load difference can be provided. This makes it possible to provide an intraocular lens insertion device that improves the tacking accuracy of the posterior support part of the intraocular lens.

[0011] The interference portion may be formed at a position between the extrusion start position and the contact position. By forming the interference portion at a position between the extrusion start position and the contact position, it becomes easier to control the extrusion load that applies resistance to the movement of the plunger. Therefore, it becomes easier to control the change in the extrusion speed of the plunger by the load difference.

[0012] The interference portion may also be configured with an inclined surface along which the tip of the plunger moves in the thickness direction of the optical portion. The inclined surface as the interference portion applies resistance to the movement of the plunger, thereby increasing the extrusion load and allowing the posterior support portion to be folded while moving onto the optical portion, thereby further improving the tacking accuracy of the posterior support portion of the intraocular lens.

[0013] The interference portion may be configured as a protruding surface that protrudes toward the inner diameter side of the passage through which the plunger tip passes. Such a protruding surface as the interference portion can suitably improve the tacking accuracy of the posterior support portion of the intraocular lens.

[0014] Furthermore, the first distance at which the first pushing load is generated may be shorter than the second distance at which the second pushing load is generated. In other words, the relationship is such that the first distance is smaller than the second distance. This ensures a longer distance between when the plunger tip starts to contact the contact position and when the posterior support part is folded onto the optical part. Therefore, the tip part of the posterior support part, which is likely to be subjected to resistance by the viscoelastic material filled in the main body part, can be directed forward more quickly. This further prevents the tip part of the posterior support part from being affected by the resistance of the viscoelastic material and being folded in a bent or twisted state, thereby improving the tacking accuracy of the posterior support part.

[0015] The interference portion may be made of a material different from that of the main body and the plunger, and when the plunger passes through the interference portion, a resistance force is applied due to deformation of the interference portion or a change in the coefficient of friction, thereby changing the thrust speed of the plunger due to the load difference. Even if the interference portion is made of a material different from that of the main body and the plunger, the tacking accuracy of the rear support portion can be suitably improved.

[0016] Exemplary embodiments of the present disclosure will now be described with reference to FIGS.

[0017] <Embodiment 1> In the following explanation, the directions shown in each drawing will be described as the direction toward the tip of the nozzle 180 side of the main body 100 of the intraocular lens insertion device 10A (the lower left side of the drawing in FIG. 1) being the front of the intraocular lens insertion device 10A, and the direction toward the pressing portion 370 of the plunger 300 (the upper right side of the drawing in FIG. 1) being the rear of the intraocular lens insertion device 10A. In addition, the upper side of the drawing in FIG. 1 will be described as the top of the intraocular lens insertion device 10A, the lower side of the drawing in FIG. 1 will be described as the bottom of the intraocular lens insertion device 10A, the lower right side of the drawing in FIG. 1 will be described as the left side of the intraocular lens insertion device 10A, and the upper left side of the drawing in FIG. 1 will be described as the right side of the intraocular lens insertion device 10A.

[0018] <Overall configuration of intraocular lens insertion device 10A> The overall configuration of an intraocular lens insertion device 10A of this embodiment will be described with reference to FIG. 1. The intraocular lens insertion device 10A is used to insert a deformable intraocular lens 1 (see FIGS. 3 and 4; details will be described later) into the eye. The intraocular lens insertion device 10A includes a main body 100 and a plunger 300. The main body 100 is substantially cylindrical, and the intraocular lens 1 is inserted into the eye through a passage inside the main body 100. The plunger 300 is a rod-shaped member that can move in the front-to-rear direction (direction along the extrusion axis A) through the passage inside the main body 100. The plunger 300 extrudes the intraocular lens 1 filled inside the main body 100 by moving forward along the extrusion axis (axis of the passage) A.

[0019] The main body 100 and plunger 300 of the intraocular lens insertion device 10A of this embodiment are formed by injection molding using a resin material (e.g., polypropylene). The intraocular lens insertion device 10A may be formed by cutting a resin, for example. The intraocular lens insertion device 10A may be a cartridge type device with a replaceable nozzle 180. By forming the intraocular lens insertion device 10A from a resin material, the user can easily dispose of the used intraocular lens insertion device 10A. Note that the intraocular lens insertion device 10A of this embodiment is a so-called preloaded type, and illustrates an example in which the intraocular lens 1 is shipped pre-loaded.

[0020] In this embodiment, a lubricating coating is applied to the inner wall of the main body 100 to smoothly insert the adhesive soft intraocular lens 1 into the eye. Furthermore, the intraocular lens insertion device 10A of this embodiment is formed to be colorless, transparent, or colorless, translucent. Therefore, the user can easily visually check the deformation state, etc., of the intraocular lens 1 loaded inside the intraocular lens insertion device 10A from the outside of the intraocular lens insertion device 10A.

[0021] <Main body 100> The main body 100 will be described with reference to Fig. 1. The main body 100 includes a tubular main body portion 110, an installation portion 130, and a nozzle 180, from the rear to the front.

[0022] The tubular main body portion 110 is formed in a cylindrical shape that extends in the front-to-rear direction. The tubular main body portion 110 is located on the rear end side of the main body portion 100. A flange portion 111 that protrudes outward from the outer peripheral surface is provided at a position on the rear end side in the longitudinal direction of the tubular main body portion 110. When using the device, the user grips the flange portion 111 with their fingers.

[0023] The setting section 130 is connected to the front end side of the main body tube section 110. The setting section 130 is configured to have a cylindrical interior and includes a setting section main body 134, a top plate section 132, etc. The setting section main body 134 is a box-shaped member with an open top. Before being pushed out by the plunger 300, the intraocular lens 1 is set (filled) inside the setting section main body 134 in the setting section 130 (see FIGS. 5 to 7).

[0024] The top plate 132 is a lid member that is disposed across the nozzle 180 and the installation unit main body 134 and covers the upper openings thereof. The top plate 132 may be formed by injection molding using a resin material (for example, polypropylene), cutting work by scraping out resin, or the like. The top plate 132 is flat and is formed so as to cover the openings of the nozzle 180 and the installation unit main body 134. The top plate 132 is provided with a groove-shaped guide portion (not shown) that guides the plunger 300 along the extrusion direction (extrusion axis A).

[0025] 1, the nozzle 180 is connected to the front end side of the installation section 130. The nozzle 180 has an insertion section 182 and a tapered section 189.

[0026] The tapered portion 189 has an internal passage area that becomes smaller toward the front in order to deform the intraocular lens 1 into a smaller shape in the process of pushing the intraocular lens 1 forward. In other words, the tapered portion 189 has a hollow passage shape (lumen shape) in which the passage through which the intraocular lens 1 passes becomes narrower toward the tip.

[0027] As shown in FIGS. 1 and 5 , the insertion portion 182 is connected to the front end of the nozzle 180. The insertion portion 182 is the portion to be inserted (inserted or inserted) into the eye. The insertion portion 182 is cylindrical. The inner surface of the insertion portion 182 has a substantially circular cross section, and the central axis coincides with the extrusion axis A. The open end face at the tip of the insertion portion 182 is formed with an inclined open end face 183 (bevel) that opens to eject the intraocular lens 1 forward from the internal passage. The inclined open end face 183 is formed in a notched shape with its tip cut obliquely and inclined with respect to an imaginary plane perpendicular to the central axis (extrusion axis A) of the insertion portion. The internal passage of the main body portion 100 penetrates from the rear end of the main body tubular portion 110 to the inclined open end face 183 at the front end of the nozzle 180. The insertion portion 182 has an open tip portion 185 located at the forefront of the inclined open end face 183. The insertion portion 182 also has a slit 187 cut out from the rearmost end face of the inclined open end face 183 toward the rear in the axial direction.

[0028] <Plunger 300> 2, a schematic configuration of the plunger 300 will be described. The plunger 300 of this embodiment includes a pushing member 310, a shaft base portion 350, and a pressing portion 370.

[0029] The pressing portion 370 is formed at the rear end of the plunger 300. The pressing portion 370 is a plate-shaped member extending in a direction perpendicular to the extrusion axis A (see FIG. 1). The pressing portion 370 is the portion that comes into contact with the user's finger when the user pushes the plunger 300 forward.

[0030] The shaft base 350 is a rod-shaped member extending forward from the front end side of the pressing portion 370. In this embodiment, the shaft base 350 is formed so that the cross section perpendicular to the extrusion axis A has a substantially H-shape. The shaft base 350 is inserted into the main body tubular portion 110, which has a substantially rectangular cross section perpendicular to the extrusion axis A, thereby suppressing circumferential rotation of the extrusion axis A of the plunger 300 relative to the main body 100. When the plunger 300 moves forward and reaches a position where insertion of the intraocular lens 1 into the eye is completed, the inclined surface at the bottom of the front end of the shaft base 350 comes into contact with an inclined surface formed at a predetermined position on the main body 100 and stops. As a result, the front end of the plunger 300 is prevented from excessively protruding from the inclined opening end face 183 (see FIG. 1 ).

[0031] The pushing member 310 is a rod-shaped member that extends forward from the front end of the shaft base 350 along the axial direction of the pushing axis A. The pushing member 310 is formed so that the cross section perpendicular to the pushing axis A has a substantially circular shape. The pushing member 310 has a thickness that allows it to pass through the inclined opening end face 183 of the main body portion 100. The pushing member 310 moves forward along the pushing axis A within the passage of the main body portion 100, thereby tacking the intraocular lens 1 and ejecting the intraocular lens 1 from the inclined opening end face 183 into the eye. The axially forward portion of the pushing member 310 is a plunger tip portion 302 that pushes out the intraocular lens 1 within the setting portion 130.

[0032] <Intraocular lens 1> 3 and 4, an example of an intraocular lens 1 to be inserted into the eye using an intraocular lens insertion device 10A will be described. The intraocular lens 1 includes an optical portion 2 and haptics 3. The intraocular lens 1 of this embodiment is a so-called one-piece type intraocular lens in which the optical portion 2 and haptics 3 are integrally molded. The intraocular lens 1 used in this embodiment is integrally molded with the optical portion 2 and a pair of haptics 3, namely, an anterior haptic portion 3A and a posterior haptic portion 3B. Various soft resin materials, such as simple substances such as BA (butyl acrylate) and HEMA (hydroxyethyl methacrylate), and composite materials of acrylic esters and methacrylic esters, can be used as the flexible material for the intraocular lens 1. Note that, although the so-called one-piece type intraocular lens 1 is illustrated in this embodiment, at least a portion of the techniques exemplified in this disclosure can also be applied to so-called three-piece type intraocular lenses in which the optical portion 2 and haptics 3 are formed as separate members.

[0033] The optical portion 2 provides a predetermined refractive power to the patient's eye. The optical portion 2 is disk-shaped. The optical axis L of the optical portion 2 passes through the center of the optical portion 2 and extends in the up-down direction. The optical portion 2 has, as end faces in the optical axis L direction, a first surface 2A facing the top plate portion 132 of the installation portion 130, as will be described later, and a second surface 2B formed on the opposite side of the first surface 2A. The support portions 3 support the optical portion 2 inside the eye. As an example, the intraocular lens 1 of this embodiment is provided with a pair of support portions 3, a front support portion 3A and a rear support portion 3B. The front support portion 3A and the rear support portion 3B extend in a curved manner radially outward from the outer peripheral edge portion 2C of the optical portion 2 and are formed in point symmetry with respect to the optical axis L, which is the center of the optical portion 2. The front support part 3A has a base portion 6A connected to the outer peripheral edge part 2C of the optical part 2 via a connecting portion 4A, and is circumferentially curved in a loop shape with an open tip portion 8A (i.e., the tip portion 8A is a free end). The rear support part 3B has a base portion 6B connected to the outer peripheral edge part 2C of the optical part 2 via a connecting portion 4B, and is circumferentially curved in a loop shape with an open tip portion 8B (i.e., the tip portion 8B is a free end). The front support part 3A is located closer to the inclined opening end face 183 than the optical part 2 within the installation part 130 of the main body part 100. The rear support part 3B is located rearward of the optical part 2 (the side away from the inclined opening end face 183) within the installation part 130 of the main body part 100.

[0034] <Interference part> 6 to 9, the "interference portion" provided in the installation portion 130 of the main body portion 100 will be described. The interference portion in this embodiment is a mechanism that increases the extrusion load by applying resistance to the movement of the plunger 300 in the extrusion direction.

[0035] The positions of the plunger 300 in the extrusion direction within the installation section 130 are defined as an extrusion start position 300A and an abutment position 300B. As shown in FIG. 6, the extrusion start position 300A is a position within the installation section 130 where the plunger tip 302 can start extrusion. As shown in FIG. 7, the abutment position 300B is a position where the plunger tip 302 abuts against the rear support section 3B. As shown in FIG. 8, the interference portion is provided in the installation section 130 from the extrusion start position 300A to the abutment position 300B (see FIG. 7), and is configured as an inclined surface 150 that protrudes from the bottom surface 136 toward the top plate portion 132 and gradually becomes higher toward the front end of the nozzle 180. The inclined surface 150 (interference portion) is formed up to the abutment position 300B, and the portion forward of that returns to the height of the bottom surface 136. As a result, the inclined surface 150 (interference portion) is configured to move toward the first surface 2A in the thickness direction of the optical portion 2 when the plunger tip portion 302 is pushed from the extrusion start position 300A to the abutment position 300B.

[0036] 6, 7, and 9, the inclined surface 150 applies resistance (frictional force of the inclined surface 150) to the movement of the plunger 300 by the time the plunger tip 302 reaches the abutment position 300B from the extrusion start position 300A, thereby increasing the extrusion load to a first extrusion load F1. The first extrusion load F1 is the load applied by resistance to the movement of the plunger 300 as the plunger tip 302 ascends the inclined surface 150 when being extruded from the extrusion start position 300A to the abutment position 300B. The second extrusion load F2 is the load applied when the plunger tip 302 begins to abut at the abutment position 300B and the rear support portion 3B is folded onto the optical portion. The inclined surface 150 is formed up to the abutment position 300B, and the front side thereafter returns to the height of the bottom surface 136. Therefore, after the plunger tip 302 passes the inclined surface 150, no resistance force is applied to the movement of the plunger 300, resulting in a second push-out load F2 that is smaller than the first push-out load F1. That is, as shown in Fig. 9, the first push-out load F1 is larger than the second push-out load F2 (first push-out load F1>second push-out load F2).

[0037] Also, as shown in FIGS. 6 and 7, the first distance D1 at which the first extrusion load F1 is generated is configured to be shorter than the second distance D2 at which the second extrusion load F2 is generated. As shown in FIG. 6, when the tip 302 of the plunger starts to pass through the inclined surface 150, due to the resistance force caused by interference, the load applied to the tip 302 of the plunger increases, and the first distance D1 until the start of the tacking of the rear support portion 3B has a slow extrusion speed (the extrusion speed decreases). As shown in FIG. 7, when the tacking of the rear support portion 3B starts, the tip 302 of the plunger passes through the inclined surface 150. Since the inclined surface 150 does not interfere with the extrusion member 310 after the tip 302 of the plunger, the resistance force disappears, the load temporarily decreases significantly, and the acceleration instantaneously switches greatly, and the extrusion speed temporarily increases (the extrusion speed increases). Therefore, due to the sudden decrease in the load, the user can quickly perform the tacking of the second distance D2 without being aware of it. Thus, the inclined surface 150 is a mechanism that changes the extrusion speed of the plunger 300 due to the load drop from the first extrusion load F1 to the second extrusion load F2 (the first extrusion load F1 > the second extrusion load F2) and folds the rear support portion 3B.

[0038] The reason why the extrusion speed of the plunger 300 temporarily increases is as follows. Assume that the force applied by the user when pushing out the plunger 300 is constant at F. Also, assume that the resistance force (frictional force) due to the inclined surface 150 (interference portion) is f. · From when the plunger 300 starts to pass through the inclined surface 150 (interference portion) until the start of the tacking of the rear support portion 3B: F - f = ma ··· (1) · After the start of the tacking of the rear support portion 3B: F = ma' ··· (2) Since both F and f are positive, F - f < F, and since m is a constant, the relationship a < a' holds. That is, the acceleration is greater in (2) than in (1), and since the acceleration instantaneously switches greatly between (1) and (2), the extrusion speed temporarily increases.

[0039] 6 to 8, the effects of employing the technique exemplified in this embodiment will be described. First, the user moves the intraocular lens 1 held in the installation part 130 to the extrusion start position 300A where the plunger tip 302 of the plunger 300 can start extruding the intraocular lens 1.

[0040] As shown in Fig. 6, the intraocular lens 1 placed in the placement unit 130 has a base portion 6A of the front support portion 3A located to the right of the extrusion axis A (upper side in Fig. 6), and a base portion 6B of the rear support portion 3B located to the left of the extrusion axis A (lower side in Fig. 6). The intraocular lens insertion device 10A of this embodiment is a so-called preset type device in which the intraocular lens 1 is loaded in advance. However, the technology exemplified in the present disclosure can also be applied to an intraocular lens insertion device in which the intraocular lens 1 is loaded just before inserting the intraocular lens 1 into a patient's eye.

[0041] The user uses a syringe or the like to inject a filler (for example, a viscoelastic substance (a lubricant such as sodium hyaluronate), water, etc.) into the installation portion 130, and causes the plunger 300 to start moving forward.

[0042] As shown in FIG. 6, when the plunger 300 is pushed out, the plunger tip 302 located at the extrusion start position 300A starts to pass through the inclined surface 150 (interference portion), and the load on the plunger tip 302 increases due to the resistance force caused by the interference, causing it to be pushed out with a first extrusion load F1, and the extrusion speed slows down (the extrusion speed decreases) over a first distance D1 until the start of tacking of the rear support portion 3B.

[0043] 7, when plunger tip 302 reaches contact position 300B and starts tucking rear support portion 3B, plunger tip 302 passes inclined surface 150. Because inclined surface 150 does not interfere with pusher member 310 after plunger tip 302, the resistance disappears, the load temporarily decreases significantly to second push-out load F2, the acceleration momentarily switches to a large value, and the push-out speed temporarily increases (the push-out speed increases). Therefore, the sudden decrease in load allows the user to quickly tack the plunger over the second distance D2 without even realizing it.

[0044] When the plunger 300 is further pushed forward, the posterior support part 3B is pushed out by the plunger tip part 302 and moves in a direction approaching the optical part 2 (i.e., forward). Thereafter, the posterior support part 3B quickly deforms and moves onto the first surface 2A of the optical part 2 (the front side in the illustration of FIG. 7) and folds. Therefore, the tip part 8B of the posterior support part 3B, which is more susceptible to resistance from the filler, can quickly face forward. As a result, the posterior support part 3B is tacked normally.

[0045] Although not shown, as the plunger 300 is further pushed forward, the intraocular lens 1 reaches the nozzle 180 and enters the tapered inner wall of the tapered portion 189. The optical portion 2 of the intraocular lens 1 then begins to deform into a roll along the curved inner wall of the tapered portion 189. The front support portion 3A remains on the inner wall of the tapered portion 189 and approaches the optical portion 2 extruded by the extrusion member 310. The front support portion 3A then deforms and moves onto the first surface 2A of the optical portion 2 and is folded, with the tip portion 8A of the front support portion 3A facing backward. As a result, the front support portion 3A is tucked. As the plunger 300 is further pushed forward, the intraocular lens 1 is folded into a small size with the front support portion 3A and rear support portion 3B tucked together. As the intraocular lens 1 is pushed axially forward within the tapered portion 189 by the push-out member 310, the passage shape of the tapered portion 189 causes the tip portion 8A of the front support portion 3A and the tip portion 8B of the rear support portion 3B to bend onto the optical portion 2 in directions approaching each other, and the lens is folded so as to wrap around the front support portion 3A and the rear support portion 3B.

[0046] The intraocular lens 1 is then inserted into the eye from the inclined opening end face 183. Here, when the intraocular lens insertion device 10A inserts the insertion portion 182 into the crystalline lens bag, the opening of the inclined opening end face 183 is oriented to face the posterior capsule of the crystalline lens. When the intraocular lens 1 is dispensed from the inclined opening end face 183, the intraocular lens 1 behaves as follows. Just before being dispensed from the inclined opening end face 183, the tacked posterior support portion 3B of the intraocular lens 1 is sandwiched between the pushing member 310 and the inner wall of the nozzle 180, and the optical portion 2 begins to unfold to an open position (restoring position) while rotating around the axis of the extrusion axis A. Finally, when the posterior support portion 3B is dispensed from the inclined opening end face 183, the intraocular lens 1 is placed in the crystalline lens with the first surface 2A facing the anterior capsule and the second surface 2B facing the posterior capsule.

[0047] <Embodiment 2> Next, a second embodiment will be described with reference to Figures 10 and 11. The configuration of the interference portion is not limited to the mode in which the inclined surface 150 is provided on the inner surface of the main body portion 100. Although the second embodiment differs in the configuration of the interference portion, the other configurations are substantially the same as those of the first embodiment. Therefore, the same reference numerals will be used to designate the same configuration as the first embodiment, and the description thereof may be omitted.

[0048] As shown in Figures 10 and 11, in the intraocular lens insertion device 10B of embodiment 2, the interference portion is provided at a position from the extrusion start position 300A to the abutment position 300B (see Figure 11) within the installation section 130, and is configured as a protruding surface 152 that protrudes toward the inner diameter side of the passage through which the plunger tip portion 302 passes.

[0049] As shown in Figure 10, when the plunger tip 302 begins to pass through the protruding surface 152 (interference portion), the load on the plunger tip 302 increases due to the resistance force caused by the interference, causing it to be pushed out with a first pushing load F1, and the pushing speed slows down (the pushing speed decreases) over a first distance D1 until the rear support portion 3B starts to tack.

[0050] 11, when tucking of the rear support part 3B begins, the plunger tip 302 passes the protruding surface 152. Because the protruding surface 152 does not interfere with the pusher member 310 after the plunger tip 302, the resistance force disappears, the load temporarily decreases significantly to the second push-out load F2, the acceleration momentarily switches to a large value, and the push-out speed temporarily increases (the push-out speed increases). Therefore, the sudden decrease in load allows the user to quickly perform tucking of the second distance D2 without even realizing it.

[0051] In this way, the protruding surface 152 functions as a mechanism for folding the rear support portion 3B by changing the extrusion speed of the plunger 300 due to the load difference between the first extrusion load F1 and the second extrusion load F2 (first extrusion load F1 > second extrusion load F2). As a result, the protruding surface 152 (interference portion) functions as a mechanism for increasing the extrusion load by applying resistance to the movement of the plunger 300 in the extrusion direction.

[0052] <Embodiment 3> Next, a third embodiment will be described with reference to Figures 12 and 13. The configuration of the interference portion is not limited to the form in which the inclined surface 150 and the protruding surface 152 are provided on the inner surface of the main body 100. Although the third embodiment differs in the configuration of the interference portion, the other configurations are substantially the same as those of the first embodiment. Therefore, the same reference numerals will be used to designate the same configurations as the first and second embodiments, and descriptions thereof may be omitted.

[0053] 12 and 13, in the intraocular lens insertion device 10C according to the third embodiment, the interference portion may be provided on the plunger 320 side. That is, it is configured as a protrusion 324 that protrudes radially outward from the outer peripheral surface of the plunger tip portion 322.

[0054] As shown in Figure 12, when the plunger tip 322 begins to pass through the passage from the extrusion start position 320A to the abutment position 320B (see Figures 12 and 13) within the installation section 130, the load on the plunger tip 322 increases due to the resistance force caused by the interference of the protrusion 324, causing it to be pushed out with a first extrusion load F1, and the extrusion speed slows down (the extrusion speed decreases) over the first distance D1 until the start of tacking of the rear support section 3B.

[0055] As shown in Figure 13, when the rear support part 3B starts to tack, the protrusion 324 of the plunger tip part 322 is released from interference. After the rear support part 3B tacks, the protrusion 324 no longer interferes, so the resistance disappears and the load temporarily decreases significantly to the second pushing load F2, causing an instantaneous change in acceleration and a temporary increase in the pushing speed (the pushing speed increases). Therefore, the sudden drop in load allows the user to quickly perform the tack of the second distance D2 without even realizing it.

[0056] In this way, the protrusion 324 functions as a mechanism for folding the rear support portion 3B by changing the extrusion speed of the plunger 320 due to the load difference between the first extrusion load F1 and the second extrusion load F2 (first extrusion load F1 > second extrusion load F2). As a result, the protrusion 324 (interference portion) functions as a mechanism for increasing the extrusion load by applying resistance to the movement of the plunger 320 in the extrusion direction.

[0057] The protruding surface 152 (interference portion) in the second embodiment and the protrusion 324 (interference portion) in the third embodiment may be made of a material different from that of the main body 100 and the plungers 300 and 320. For example, they may be made of a material such as soft resin or rubber that is softer than that of the main body 100 and the plungers 300 and 320. In such a case, when the protruding surface 152 (interference portion) and the protrusion 324 (interference portion) function as an interference portion, they can exert resistance as they deform or increase in the coefficient of friction. This allows the configuration to change the extrusion speed of the plungers 300 and 320 due to the load difference, thereby suitably improving the tacking accuracy of the rear support portion 3B. Furthermore, they may be made of a hard resin that is harder than that of the main body 100 and the plungers 300 and 320. In such a case, when the protruding surface 152 (interference portion) and the protrusion 324 (interference portion) function as an interference portion, they can exert resistance as they are crushed (deformed). As a result, the tacking accuracy of the rear support portion 3B can be suitably improved by changing the extrusion speed of the plungers 300, 320 depending on the load drop.

[0058] As described above, according to the intraocular lens insertion devices 10A, 10B, and 10C according to the first to third embodiments of the present disclosure, the tacking accuracy of the rear support portion 3B of the intraocular lens 1 can be improved.

[0059] Furthermore, by configuring the inclined surface 150, protruding surface 152, and protrusion 324 as interference portions at positions from the extrusion start positions 300A, 320A to the contact positions 300B, 320B, it becomes easier to control the extrusion load that applies resistance to the movement of the plungers 300, 320. Therefore, it becomes easier to control the change in the extrusion speed of the plungers 300, 320 by the load difference.

[0060] Furthermore, the inclined surface 150 acting as an interference portion applies resistance to the movement of the plungers 300, 320, thereby increasing the extrusion load, and the rear support portion 3B can be folded while being moved onto the optical portion, thereby further improving the tacking accuracy of the rear support portion 3B in the intraocular lens 1.

[0061] Furthermore, the protruding surface 152 as an interference portion can suitably improve the tacking accuracy of the rear support portion 3B of the intraocular lens.

[0062] Furthermore, the distance from when the plunger tips 302, 322 start to contact the contact positions 300B, 320B until the posterior support part 3B is folded onto the optical part is further ensured. Therefore, the tip part 8B of the posterior support part 3B, which is likely to experience resistance from the viscoelastic material filled in the main body part 100, can be directed forward more quickly. This further prevents the tip part 8B of the posterior support part 3B from being affected by the resistance of the viscoelastic material and being folded in a bent or twisted state, thereby improving the tacking accuracy of the posterior support part 3B.

[0063] Furthermore, even if the interference portion is made of a material different from the material that the main body portion 100 and the plungers 300, 320 are made of, the tacking accuracy of the rear support portion 3B can be suitably improved.

[0064] Although the embodiments of the present disclosure have been described above, the intraocular lens insertion device of the present disclosure is not limited to the above-described embodiments and can be embodied in various other forms.

[0065] For example, the interference portion is not limited to being formed in a position from the extrusion start position 300A, 320A to the abutment position 300B, 320B. Here, in the first and second embodiments, an aspect in which the inclined surface 150 and the protruding surface 152 (interference portion) are provided on the plunger tip portion 302 of the ejection member 310 in the plunger 300 has been described. Furthermore, in the third embodiment, an aspect in which the protrusion 324 (interference portion) is provided on the plunger 320 has been described. These embodiments are examples of a configuration in which "at least one of the inner surface of the plunger or the main body has an interference portion that applies resistance to the movement of the plunger by the time the plunger tip portion reaches the abutment position from the extrusion start position, thereby increasing the extrusion load." In other words, it is sufficient that the interference portion functions by the time the plunger tip portion reaches the abutment position from the extrusion start position. For this reason, for example, an inclined surface, a protruding surface, a protrusion, or the like may be provided as an interference portion on the sliding surface between the outer peripheral surface of the shaft base 350 of the plunger 300, 320 and the inner surface of the tubular main body portion 110 of the main body portion 100. The interference portion may also be configured as a combination of an inclined surface, a protruding surface, a protrusion, or the like. Alternatively, the interference portion may be configured on both the plunger 300, 320 and the inner surface of the main body portion 100. These embodiments can also suitably improve the tacking accuracy of the rear support portion 3B. [Explanation of symbols]

[0066] 1. Intraocular lenses 2 Optical Department 2A 1st page 2B 2nd side 2C Outer edge 3 Support part 3A Front support part 4A Connection part 6A Base part 8A tip part 3B Rear support part 4B Connection part 6B Base part 8B Tip part 10A Intraocular lens insertion device 100 Main body 110 Main body cylindrical part 111 Tsuba 130 Installation section 132 Top plate 134 Installation unit main body 136 bottom 150 Inclined surface (interference area) 180 nozzles 182 Insertion section 183 Slanted opening end face 185 Opening tip 187 Slit 189 Tapered section 300 Plunger 300A extrusion start position 300B Contact position 302 Plunger tip 310 Extrusion member 350 shaft base 370 Pressing section A Extrusion shaft (center shaft) L optical axis F1 1st extrusion load F2 2nd extrusion load D1 First distance D2 2nd distance 10B Intraocular lens insertion device 152 Protruding surface (interference part) 10C Intraocular lens insertion device 320 Plunger 320A Extrusion start position 320B Contact position 330 Extrusion member 322 Plunger tip 324 Protrusion (interference part)

Claims

1. An intraocular lens insertion device that inserts an intraocular lens into an eye by pushing an intraocular lens installed in a cylindrical main body from a rear side of the main body to a front side of the main body in an axial direction using a rod-shaped plunger inserted into the main body, and by pushing the intraocular lens in a small folded state outward from a tip side of the main body, The intraocular lens installed in the main body portion includes a disk-shaped optical portion and a pair of support portions extending radially outward from an outer peripheral edge of the optical portion, and one of the support portions, a front support portion, is disposed forward of the optical portion in the axial direction, and the other support portion, a rear support portion, is disposed rearward of the optical portion in the axial direction, an interference portion that applies resistance to the movement of the plunger and increases the pushing load on at least one of the plunger and the inner surface of the main body portion from the pushing start position where the tip end of the plunger starts to be pushed out to the contact position where the tip end of the plunger contacts the rear support portion, Based on the interference portion, a first pushing load until the plunger tip is positioned at the abutment position is greater than a second pushing load until the plunger tip starts to abut at the abutment position and the rear support portion is folded onto the optical portion, and an intraocular lens insertion device having a mechanism for changing the pushing speed of the plunger based on this load difference to fold the rear support portion.

2. The intraocular lens insertion device according to claim 1, The interference portion is configured at a position from the extrusion start position to the abutment position in the intraocular lens insertion device.

3. The intraocular lens insertion device according to claim 2, The interference portion is an intraocular lens insertion device having an inclined surface along which the tip of the plunger moves in the thickness direction of the optical portion.

4. The intraocular lens insertion device according to claim 2 or 3, The interference portion is configured as a protruding surface that protrudes toward the inner diameter side of the passage through which the plunger tip portion passes.

5. The intraocular lens insertion device according to any one of claims 1 to 4, An intraocular lens insertion device configured such that a first distance at which the first pushing load is generated is shorter than a second distance at which the second pushing load is generated.

6. The intraocular lens insertion device according to any one of claims 1 to 5, The interference portion is made of a material different from the material of the main body portion and the plunger, and when the plunger passes through the interference portion, resistance force is applied due to deformation of the interference portion or change in the friction coefficient, thereby changing the extrusion speed of the plunger due to load drop.

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