WO2015168009A1

WO2015168009A1 - Apparatus for injecting an intraocular lens

Info

Publication number: WO2015168009A1
Application number: PCT/US2015/027775
Authority: WO
Inventors: Ravi Nallakrishnan; Takayuki Akahoshi
Original assignee: Ravi Nallakrishnan; Takayuki Akahoshi
Priority date: 2014-04-27
Filing date: 2015-04-27
Publication date: 2015-11-05

Abstract

An injector is disclosed for injecting an intraocular lens into an eye. The injector has a hollow housing for housing an intraocular lens, and has a length defining a housing axis. The housing has an interior surface Iocated radially outward from the housing axis. The injector has a plunger movable relative to the housing generally along the housing axis. The plunger has a distal end for moving an intraocular lens generally along the housing axis, and further has a proximal end for being forced by a user of the injector. The plunger further has an exterior surface. The injector has at least one control member Iocated between the housing interior surface and the plunger exterior surface configured to control at least one of: (a) a velocity of the plunger distal end; and (b) an acceleration of the plunger distal end.

Description

APPARATUS FOR INJECTING AN INTRAOCULAR LENS Field of the Invention

[0001] The present invention relates to an apparatus or injector that is used to inject an intraocular lens (hereinafter lOL") into an eye of a patient. An injector generaiiy of this type is shown in U.S. Patent No. 8,685,088 B2, the disclosure of which is hereby incorporated by reference.

Background of the Invention

[0002] A typical !OL injector has a housing into which an lOL is placed. The lOL is typically folded or otherwise placed in a compressed state within the housing. The injector housing is elongate and has a proximal end and a distal end. The distal end of the housing is located c!osest to a patient's eye. A plunger is retained within the housing and is movable with respect to the housing. Movement of the plunger through the housing is generally characterized as linear, along an axis defined by the housing. The plunger has a proximal end with a thumb plate or finger contacting member which may be pressed during use when the plunger is pushed forward toward the distal end of the housing. The housing has a gripping member or finger plate that enables the user of the injector to grip the injector, counterbalancing the force applied to the plunger finger contact member.

[0003] In operation of the injector, the lOL is pressed forward by a distal end of the plunger for insertion into a patient's eye. The !OL may further be compressed by a narrowed tip or nozzle that may be attached to the housing distal end, which enables the iOL to travel through a variety of incision sizes in the eye while the IOL is in the compressed state. The iOL will expand to an uncompressed state upon entering the eye and exiting the nozzle. Such a rapid expansion can lead to a release of potential energy and cause undesirable recoil or push back to the injector plunger and/or housing. This unfolding of the IOL has heretofore tended to cause the plunger to undesirably push back, giving the user a feedback sensation of unwanted motion to the particular physician inserting the IOL info the patient's eye. Such motion can conceivably cause damage to the patient's eye in the form of rupture to the capsule or even damage to the IOL itself. A user of typical injector may therefore fend to over-force or under-force the plunger in anticipation or surprise in response to this release of energy.

[0004] It would be desirable for an IOL injector to provide improved feedback to the user. It would further be desirable for an IOL injector to reduce or minimize over and under-forcing of the IOL It would further be desirable for such an injector to be cheap to manufacture and easy to assemble, and configured for disassembly to be sanitized for reusability.

Summary of the Invention

[0005] In accordance with the present invention, an injector is provided fo injecting an intraocular lens into an eye. The injector has a hollow housing configured to house an intraocular lens, and has a length that defines a housing axis. The housing has an interior surface located radially outward from the housing axis. The injector has a plunge movable relative to the housing generally along the housing axis. The piunger has a distal end and a proximal end. The plunger proximal end is for being forced by a user of the injector to move the plunger and the plunger distal end is for moving an intraocular lens generally along the housing axis. The piunger has an exterior surface. The injector further has at least one control member located between the housing interior surface and the plunger exterior surface, which is configured to control at least one of: (a) a velocity of the plunger distal end; and (b) an acceleration of the plunger distal end.

Brief Description of the Drawings

[0001] FIG. 1 is a perspective view of a first embodiment of an injector according to the present invention;

[0002] FIG. 2 is a perspective view of the injector illustrated in FIG. 1 , except FIG.

2 shows the injector in a moved position;

[0003] FIG. 3 is an exploded view .of the injector illustrated in FIG. 1 ;

[0004] FIG. 4 is a partial perspective view of the plunger distal of the injector illustrated in FIG, 1 ;

[0005] FIG. 5 is an exploded view of a second embodiment of an injector according to the present invention; and

[0008] FIG. 6 is a partial, cross-sectional view of the injector illustrated in FIG. 5.

Detailed Description of the Preferred Embodiments

[0007] A first embodiment of an iOL injector in accordance with the present invention is illustrated in FIGS. 1-4 and is generally referred to by numeral 20. Referring first to FIG. 3, the injector 20 has a hollow housing 30 with an interior surface 32 that is configured to contain an IOL or cartridge containing an IOL (not iliustrated). The housing 30 is elongate, having distal end 34, a proximal end 38, and a length therebetween defining a housing axis. The housing has an aperture 38 at a distal end 34 for receiving a cartridge containing an IOL (not illustrated). The housing aperture 38 has at least one locking feature for retaining the IOL cartridge during the operation of injector 20. The housing proximai end 36 has a finger plate 40 for providing a gripping surface for the user of the injector 20, which will be discussed in detail below. The finger plate 40has the form of a partial disc, although it will be appreciated that the finger plate 40 may have other forms such as a square, or other polygon, an indentation, or irregular protrusion extending from the housing 30. The housing is preferably molded from a polycarbonate plastic.

Still referring to FIG. 3, the first illustrated embodiment of the injector 20 has a plunger, which may be unitary or comprised of multiple components, and which is inserted into the housing 30 and is movable relative to the housing 30 generally along the housing axis 100. The plunger is elongate and has a proximal end 50 and a distai end 52. The plunger has a slot or guide 51 (as best seen in FIG. 4) for cooperating with a slot or guide (not visible) inside of the housing 30 to prevent relative rotation of the plunger with respect to the housing 30. The proximal end 50 of the plunger is adapted to be forced by a thumb of the user of the injector 20, counterbalancing the force of the user's fingers against the housing finger plate 40. The balanced forces result in movement of the operative, distal end 52 of the plunger, which is configured to move the 101 from a location within the housing 30 to a location outside of the housing 30, aiong the axis. The proximal end 50 of the plunger has a thumb plate 54 secured to the plunger proximal end 52 by an attachment means, such as a press fit, adhesive, weld, or screw 55. A gripping ring 58 is attached to the thumb plate 54 for retaining a user's thumb against the proximal end 52 of the plunger. An end cap 44 is threadably secured, or otherwise removably secured, to the housing proximal end 36 for retaining the plunger proximal end 50 within the housing 30.

It will be understood that the plunger may be unitary or may be comprised of several components. The distal end 52 is preferably a slender metallic shaft that is attached to a rigid plastic body, preferably Nylon 6, 50% glass filled, of the plunger proximal end 50. It will be appreciated that the plunger may be unitari!y molded or formed of a unitary metallic part. The metallic shaft has a flaring distal end. The plunger components may be press-fit, threaded, adhered, or welded together, or any other means of attachment.

] The plunger distal end 52 has a reduced thickness compared to the plunger proximal end 50, for allowing the plunger distal end 52 to push the lOL through a narrowed nozzle (not illustrated) during injection of the lOL into the eye. The thickened proximal end 50 of the plunger has one or more, and preferably two, annular recesses or grooves for retaining a plurality of control members 70 made of silicone rubber (the operation of which wiil be discussed in detail below). [00011] Referring to FIGS. 1 and 2, the injector has a compression spring 60 for biasing the plunger to a first, unactuated position where the plunger proximal end 50 extends a furthest distance from the housing proximal end 36, and the plunger distal end 52 remains within the housing 30. The spring 80 provides linear resistance against the force applied to the plunger as it moves along the housing axis toward the distal end 34 of the housing and the stored lO^'L When compressed, the plunger moves to a second, actuated position where the plunger distal end 52 extends from the housing 30.

[00012] Referring to FIG. 3, the injector 20 further has at least one, and preferably a plurality of control members 70 for controlling the velocity of the plunger distal end 52 and/or the acceleration of the plunger distal end 52. The control members ZOare located between the housing interior surface 32 and an exterior surface of the plunger, preferabl the thickened proximal end 50. In the illustrated embodiment, the injector 20 has two control members 70 in the form of resilient G-rings carried in the recesses 52 of the plunger proximal end 50. It will be understood that the control members 70 may alternatively be carried in one or more recesses in the housing 30; and further that the control members 70 need not be O-rings. The control members 70 may be resilient, elastic sleeves, beads, or elongate protrusions that resist movement of the plunger relative to the housing 30. in the illustrated first embodiment of the injector, the two O-rings are located proximal a connection point between the metallic plunger distal end 52 and the plastic proximal end 50 of the plunger. [00013] The inventor has discovered that the IOL injector 20 according to the illustrated first embodiment can allow for user-specified control of the plunger and/or control of the potential energy released by insertion of the !OL. The control members 70 of the injector 20 serve to limit the forcing capability of the user of the injector 20, thus reducing the risk of over-riding and under-riding of the IOL insertion. Reduced risk of rupturing of the capsule of the eye may also be achieved. By limiting the velocity and/or the acceleration of the plunger distal end 52, the injector 20 disclosed herein may increase patient safety and operation reliability and consistency. As the plunger distal end 52 contacts the IOL, which may travel along a narrow passage or nozzle, and the IOL is released into the eye, a recoiling force or rocketing force may tend to suddenly push the plunger proximal end 50 back toward the user. The control members 70 may limit such recoil of the plunger upon unfolding of the SOL at the surgical site.

[00014] FIGS. 5-6 illustrate a second embodiment of an injector 20A according to the present invention. The second embodiment of the injector 20A functions in the same manner as the first embodiment of the injector 20 discussed above. However, the second embodiment 20A separates the control members 70A, in the form of two O-rings, along a greater distance on the plunger proximal portion 50A, for providing increased stability and control of the plunger as it moves through housing 20A. Furthermore, the second embodiment of the injector 20A has a seal member 90A located between the proximal end 50A of the plunger and the housing 30A for sealing between a plunger exterior surface and the housing inner surface 32A. [00015] Housing 30A has a finger recess 31 A for allowing the user to grip the housing 30A, as an alternative to the finger plate 40 in the first embodiment. End cap 44A has a pin for engaging a slot in the proximal end of the housing 30A for allowing removal of the plunger from the housing 30A.

[00018] Another feature of the plunger of the injector 20A is that it is further separated into a multitude of elongate components. Distal end 52A of the plunger is secured within a proximal sleeve 84A and proximal end 50A of the plunger by a set screw 88A. A plunger proximal rod 80A is press fit into an aperture of the proximal sleeve 84A. The modular construction of the plunger in the second embodiment of the irjecfor 20A allows for complete disassembly and sanitization/replacement of specific plunger components for re-use of the injector 20A.

Claims

CLAM:

1. An injector for injecting an intraocular lens into an eye, said injector comprising:

A hollow housing configured to house an intraocular lens, said housing having length defining a housing axis, said housing having an interior surface located radially outward from said housing axis;

A plunger movable relative to said housing generally along said housing axis, said plunger having a distal end and a proximal end, said plunger proximal end for being forced by a user of said injector, said plunger distal end for moving an intraocular !ens generally along said housing axis, said plunger having an exterior surface: at least one control member located between said housing interior surface and said plunger exterior surface, said at least one control member configured to control at least one of: (a) a velocity of said plunger distal end; and (b) an acceleration of said plunger distal end.

2. The injector of claim 1 wherein said control member is resilient,

3. The injector of claim 2 wherein said control member is an O-ring.

4. The injector of claim 1 wherein said control member defines a sliding seal between said housing interior surface and said plunger exterior surface.

5. The injector of claim 1 wherein said control member is attached to said plunger.

6. The injector of claim 5 wherein said control member is attached to said plunger at a location closer to said plunger distal end than said plunger proximal end.

7. The injector of claim 1 wherein said contro! member is attached to said housing.

8. The injector of claim 1 wherein said injector comprises at ieast two control members.

9. The injector of claim 1 wherein said injector has a plurality of control members, at least one of said plurality of control members located on a thickened portion of said plunger.

10. The injector of claim 1 wherein said injector has two control members located within two annular grooves on said plunger exterior surface.

11. The injector of claim 1 wherein said plunger is an assembly of a plurality of elongate members.

12. The injector of claim 11 wherein said plunger has at Ieast (i) a proximal member for contacting the at Ieast one control member, and (ii) a distal member separable from said proximal member, said distal member for contacting an intraocular lens.

13. The injector of claim 1 wherein said plunger is removable form said housing proximal end.

14, The injector of claim 1 further comprising a spring member for biasing said plunger with respeci to said housing.