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EP-4238537-B1 - INTRAOCULAR LENS INSERTION INSTRUMENT

EP4238537B1EP 4238537 B1EP4238537 B1EP 4238537B1EP-4238537-B1

Inventors

  • INOUE, Youta
  • NAGASAKA, SHINJI
  • HISHIDA, Takahiro
  • KAMIYA, TOMOAKI

Dates

Publication Date
20260506
Application Date
20230301

Claims (6)

  1. An intraocular lens insertion instrument comprising: a tubular main body portion (100) where an intraocular lens (1) is placed; a rod-like pushing member (310) inserted into the main body portion (100) and configured to press the intraocular lens (1) from a back toward a front of the main body portion (100) in an axial direction, thereby push the intraocular lens (1) in a folded state from a distal end of the main body portion (100) to the outside, and then insert the intraocular lens (1) into an eye; and a cylindrical insertion portion (182) placed in the distal end of the main body portion (100) to be inserted into the eye, wherein the insertion portion (182) includes a stress concentrated area (185y, 185z, 187y, 187z) where stress to be generated upon the folded intraocular lens (1) passing through the insertion portion (182) is concentrated, the insertion portion (182) includes, in a distal end thereof, an inclined opening end surface (183) inclined relative to a virtual plane orthogonal to the central axis of the insertion portion (182), and the insertion portion (182) includes: an opening tip portion (185) located at an extreme tip of the inclined opening end surface (183); and a slit (187) cut backward in the axial direction from an end surface located at a backmost end of the inclined opening end surface (183), characterized in that the insertion portion (182) includes a thick-walled structure in at least a part thereof, in which a thickness of the stress concentrated area (185y, 185z, 187y, 187z) of the insertion portion (182) is set to be relatively greater than a thickness of an area of the insertion portion (182) outside the stress concentrated area (185y, 185z, 187y, 187z) as the insertion portion (182) is viewed in a direction of a central axis thereof, and the thick-walled structure is formed on at least one of a side surface of a portion, which serves as the opening tip portion (185), of the insertion portion (182), and a side surface of a portion, which serves as the slit (187), of the insertion portion (182).
  2. The intraocular lens insertion instrument according to claim 1, wherein the stress concentrated area (185y, 185z, 187y, 187z) of the insertion portion (182) is an area where the stress is concentrated in response to a repulsive force generated in a direction where the folded intraocular lens (1) recovers an original shape thereof.
  3. The intraocular lens insertion instrument according to claim 1 or 2, further comprising a tapered portion (189) continuous with a back of the insertion portion (182) in the axial direction, the tapered portion (189) having a hollow passage shape where a passage through which the intraocular lens (1) passes gradually reduces in area toward a distal end thereof, wherein the intraocular lens (1) includes: a disc-shaped optical portion (2); a front support portion (3A) extending outward in a radial direction from an outer edge portion (2C) of the optical portion (2), the front support portion (3A) being located on a front side in the axial direction, which is a side closer to the insertion portion (182), in the tapered portion (189); and a back support portion (3B) extending outward in the radial direction from the outer edge portion (2C) of the optical portion (2), the back support portion (3B) being located on a back side in the axial direction, which is opposite to the insertion portion (182), in the tapered portion (189), as the intraocular lens (1) is pushed forward in the axial direction by the pushing member (310) in the tapered portion (189), the intraocular lens (1) becomes folded in such a manner that, adjusting to the passage shape of the tapered portion (189), a distal end portion of the front support portion (3A) and a distal end portion of the back support portion (3B) are folded onto the optical portion (2) in a direction of moving closer to each other and the optical portion (2) wrap the front support portion (3A) and the back support portion (3B), and the stress concentrated area (185y, 185z, 187y, 187z) is an area where the stress is concentrated in response to a repulsive force generated in a direction where the back support portion (3B) of the folded intraocular lens (1) recovers the original shape.
  4. The intraocular lens insertion instrument according to any one of claims 1 to 3, wherein the thick-walled structure is formed on each of the side surface of the portion, which serves as the opening tip portion (185), of the insertion portion (182), and the side surface of the portion, which serves as the slit (187), of the insertion portion (182).
  5. The intraocular lens insertion instrument according to claim 4, wherein the thick-walled structure is formed in such a manner that the side surface of the portion, which serves as the opening tip portion (185), of the insertion portion (182) is different in thickness from the side surface of the portion, which serves as the slit (187), of the insertion portion (182).
  6. The intraocular lens insertion instrument according to claim 4, wherein the thick-walled structure is formed in such a manner that the side surface of the portion, which serves as the opening tip portion (185), of the insertion portion (182) is equal in thickness to the side surface of the portion, which serves as the slit (187), of the insertion portion (182).

Description

BACKGROUND 1. Technical Field The present disclosure relates to an intraocular lens insertion instrument. 2. Related Art As one of methods of cataract surgery, a method for inserting a soft foldable intraocular lens into the eye instead of the crystalline lens is generally used. Moreover, an intraocular lens may be inserted forward of the crystalline lens to correct the refractive power of the eye. An intraocular lens insertion instrument called an injector may be used to insert an intraocular lens into the eye. Such an injector is disclosed in, for example, Japanese Patent JP 5 658 992 B2. In a form described in Japanese Patent JP 5 658 992 B2, an intraocular lens is pushed, by means of a pushing shaft, in a nozzle having a hollow passage that allows passage of the intraocular lens therethrough and that gradually reduces in area toward a distal end thereof. Consequently, the intraocular lens is folded into a small size, and ejected to the outside from the distal end of the nozzle. An injector such as described in Japanese Patent JP 5 658 992 B2 is inserted into the eye through the wound of an incision made in the cornea. In recent years, the trend toward micro-incision surgery is accelerating in cataract surgery. In other words, it is desired to make an insertion portion, which is the nozzle end of the injector, narrow in response to a demand for micro-incision surgery. WO 2012 / 086 797 A1 discloses an intraocular lens insertion instrument having the features in the preamble of claim 1. EP 2 641 568 A1 and WO 98 / 37 830 A2 disclose further prior art. SUMMARY An intraocular lens insertion instrument including: a tubular main body portion where an intraocular lens is placed; a rod-like pushing member inserted into the main body portion and configured to press the intraocular lens from a back toward a front of the main body portion in an axial direction, thereby push the intraocular lens in a folded state from a distal end of the main body portion to the outside, and then insert the intraocular lens into an eye; and a cylindrical insertion portion placed in the distal end of the main body portion to be inserted into the eye, in which the insertion portion includes a stress concentrated area where stress to be generated upon the folded intraocular lens passing through the insertion portion is concentrated, and the insertion portion includes a thick-walled structure in at least a part thereof, in which a thickness of the stress concentrated area of the insertion portion is set to be relatively greater than a thickness of an area of the insertion portion outside the stress concentrated area as the insertion portion is viewed in a direction of a central axis thereof. Further, in the intraocular lens insertion instrument, the insertion portion includes, in a distal end thereof, an inclined opening end surface inclined relative to a virtual plane orthogonal to the central axis of the insertion portion. The insertion portion includes: an opening tip portion located at an extreme tip of the inclined opening end surface; and a slit cut backward in the axial direction from an end surface located at a backmost end of the inclined opening end surface. The thick-walled structure is formed on at least one of a side surface of a portion, which serves as the opening tip portion, of the insertion portion, and a side surface of a portion, which serves as the slit, of the insertion portion. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an entire perspective view illustrating an intraocular lens insertion instrument;Fig. 2 is a perspective view illustrating a plunger;Fig. 3 is a plan view of an intraocular lens;Fig. 4 is a right side view of the intraocular lens;Fig. 5 is a side view illustrating a placement portion and a nozzle of the intraocular lens insertion instrument;Fig. 6 is a plan view illustrating the placement portion and the nozzle of the intraocular lens insertion instrument;Fig. 7 is an enlarged view illustrating an enlarged insertion portion of the nozzle of the intraocular lens insertion instrument;Fig. 8 is a cross-sectional view taken along line VIII-VIII of Fig. 7;Fig. 9 is a cross-sectional view taken along line IX-IX of Fig. 7;Fig. 10 is across-sectional view taken along line X-X of Fig. 7;Fig. 11 is a schematic explanatory diagram illustrating a state where the intraocular lens is placed in the placement portion;Fig. 12 is a schematic explanatory diagram illustrating a state where a pushing member has started pushing the intraocular lens;Fig. 13 is a schematic explanatory diagram illustrating a state where the intraocular lens has moved toward the nozzle;Fig. 14 is a schematic explanatory diagram illustrating a state where the intraocular lens has started making an entry into the nozzle;Fig. 15 is a schematic explanatory diagram illustrating a state where the intraocular lens deforms in the nozzle;Fig. 16 is a schematic explanatory diagram illustrating a state where the intraocular lens has deformed further