U.S. patent application number 10/213546 was filed with the patent office on 2002-12-19 for iol insertion apparatus with iol engagement structure and method for using same.
This patent application is currently assigned to Allergan Sales, Inc.. Invention is credited to Brady, Daniel G., Glick, Robert E., Ott, Robert D..
Application Number | 20020193805 10/213546 |
Document ID | / |
Family ID | 25208354 |
Filed Date | 2002-12-19 |
United States Patent
Application |
20020193805 |
Kind Code |
A1 |
Ott, Robert D. ; et
al. |
December 19, 2002 |
IOL insertion apparatus with IOL engagement structure and method
for using same
Abstract
An IOL insertion apparatus including a cartridge with an
IOL-receiving chamber, a handpiece into which the cartridge is
loaded, and a plunger rod that extends through a lumen in the
cartridge to reliably engage the IOL therein. The chamber has a
recess in one wall that creates a space adjacent the proximal edge
of the IOL positioned therein. A lip or projection on the plunger
rod is aligned with the space to extend underneath the proximal
edge of the IOL. The plunger rod may define a forked end with a
groove into which the proximal edge of the IOL is captured. The
cartridge may be of the type that folds the IOL therein. The recess
may continue the entire length of the cartridge to guide the
plunger rod therethrough. The cartridge lumen may converge so that
the IOL is further compressed therealong. An inwardly-directed wall
portion in the cartridge may help guide the lip of the plunger rod
into the recess.
Inventors: |
Ott, Robert D.; (Irvine,
CA) ; Glick, Robert E.; (Lake Forest, CA) ;
Brady, Daniel G.; (San Juan Capistrano, CA) |
Correspondence
Address: |
STOUT, UXA, BUYAN & MULLINS LLP
4 VENTURE, SUITE 300
IRVINE
CA
92618
US
|
Assignee: |
Allergan Sales, Inc.
Irvine
CA
|
Family ID: |
25208354 |
Appl. No.: |
10/213546 |
Filed: |
August 6, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10213546 |
Aug 6, 2002 |
|
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|
09812054 |
Mar 19, 2001 |
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6447520 |
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Current U.S.
Class: |
606/107 |
Current CPC
Class: |
A61F 2/1678
20130101 |
Class at
Publication: |
606/107 |
International
Class: |
A61F 009/00 |
Claims
What is claimed is:
1. An apparatus for inserting an intraocular lens through an
incision into an eye, comprising: a cartridge having a longitudinal
lumen, the cartridge including an injection tube on a distal end
with a mouth opening to the lumen, and an intraocular lens chamber
on a proximal end sized to contain an intraocular lens and forming
part of the lumen, the intraocular lens having a proximal edge and
a distal edge, the intraocular lens chamber being configured with
at least a portion having a non-circular cross-section such that,
with the intraocular lens positioned therein, a space along one
wall is created adjacent to the proximal edge of the intraocular
lens; a housing adapted to hold the cartridge and having a lumen
generally aligned with the cartridge lumen; and a plunger rod
adapted to be linearly displaced along the housing lumen and into
the cartridge lumen, the plunger rod being generally aligned with
the cartridge lumen and having an engaging head with a distal lip
aligned with the space, wherein displacement of the plunger rod in
a distal direction causes the distal lip to enter the space
adjacent the proximal edge of the intraocular lens such that the
engaging head reliably engages the intraocular lens.
2. The apparatus of claim 1, wherein the chamber opens at a hinge
so that the intraocular lens can be folded therein.
3. The apparatus of claim 1, wherein the longitudinal lumen
converges from the chamber to the distal mouth such that the
intraocular lens is compressed in size upon passage
therethrough.
4. The apparatus of claim 1, wherein the space is defined by a
recess formed in the one wall, the recess continuing as a
longitudinal channel through at least a portion of the longitudinal
lumen.
5. The apparatus of claim 4, wherein the channel continues through
the entire longitudinal lumen.
6. The apparatus of claim 4, wherein the cartridge further defines
an axially extending wall portion that projects inwardly to the
chamber opposite from the recess, and wherein the distance between
the innermost edge of the wall portion and the one wall of the
chamber is such that the wall portion may contact the engaging head
and align the distal lip with the recess.
7. The apparatus of claim 1, wherein the space is defined by a
recess formed in the one wall only at the proximal end of the
cartridge.
8. The apparatus of claim 7, wherein the recess is a chamfer
extending radially outward of the one wall.
9. The apparatus of claim 1, wherein a raised area extends inward
from the one wall of the cartridge such that the proximal edge of
the intraocular lens positioned thereon is lifted above the one
wall to define the space.
10. The apparatus of claim 1, wherein the engaging head of the
plunger rod has a forked end defined by the distal lip and another
lip spaced therefrom, with a groove formed therebetween for
capturing the proximal edge of the intraocular lens.
11. The apparatus of claim 10, wherein the engaging head has a
flattened oval-shaped body, with an axially-extending projection on
one wide side that terminates in the distal lip.
12. The apparatus of claim 10, wherein one of the lips extends
axially farther than the other.
13. An apparatus for inserting an intraocular lens through an
incision into an eye, comprising: a cartridge for receiving an
intraocular lens in a proximal chamber, the cartridge including a
distal injection tube having a lumen in communication with the
chamber along a common axis, the chamber further including a
generally tubular wall and being configured such that, with the
intraocular lens positioned therein, a space along the wall is
created adjacent to the proximal edge of the intraocular lens; and
a handpiece for mounting the cartridge, the handpiece including a
plunger rod adapted to be displaced generally along the axis, the
plunger rod including a bifurcated distal end having a pair of lips
separated by a groove sized to receive the proximal edge of an
intraocular lens, wherein one lip of the plunger rod is aligned
with the space adjacent to a proximal edge of the intraocular lens
positioned in the chamber such that displacement of the plunger rod
reliably captures the proximal edge within the groove.
14. The apparatus of claim 13, wherein the chamber opens at a hinge
so that an intraocular lens can be folded therein.
15. The apparatus of claim 13, wherein the lumen converges from the
chamber through the injection tube such that an intraocular lens is
compressed in size upon passage therethrough.
16. The apparatus of claim 13, wherein the space is defined by a
recess formed in the wall, the recess continuing as a longitudinal
channel through at least a portion of the lumen.
17. The apparatus of claim 16, wherein the channel continues
through the entire lumen.
18. The apparatus of claim 16, wherein the cartridge further
defines an axially extending wall portion that projects inwardly to
the chamber opposite from the generally tubular wall, and wherein
the distance between the innermost edge of the wall portion and the
wall of the chamber is such that the wall portion contacts or is in
close proximity to the distal end of the plunger rod and may align
the one lip with the space.
19. The apparatus of claim 13, wherein the space is defined by a
recess formed in the wall only at the proximal end of the
cartridge.
20. The apparatus of claim 19, wherein the recess is a chamfer
extending radially outward of the wall.
21. The apparatus of claim 13, wherein a raised area extends inward
from the wall of the cartridge such that the proximal edge of the
intraocular lens positioned thereon is lifted above the wall to
define the space.
22. The apparatus of claim 13, wherein the plunger rod defines an
engaging head on a distal end with a flattened oval-shaped body and
an axially-extending projection on one wide side that terminates in
said one lip.
23. The apparatus of claim 13, wherein the lip of the plunger rod
that is aligned with the space extends axially farther than the
other lip.
24. A method of inserting an intraocular lens into an eye,
comprising: providing a cartridge including a chamber for receiving
an intraocular lens and a delivery lumen defining an axis and
extending distally therefrom through an insertion tube; providing a
housing for mounting the cartridge; providing a plunger rod axially
slidable within the housing and having a length sufficient to
extend completely through the cartridge when mounted in the
housing, the plunger rod having an engaging head on its distal end
with an axially extending lip; placing an intraocular lens within
the cartridge, the chamber being configured such that a space is
created adjacent a proximal edge of an intraocular lens positioned
therein; mounting the cartridge with the intraocular lens therein
in the housing with the plunger rod retracted in a proximal
direction; positioning the insertion tube within an eye; axially
advancing the plunger rod in a distal direction such that the lip
enters the space prior to contact between the engaging head and the
proximal edge of the intraocular lens; further axially advancing
the plunger rod such that the engaging head contacts the proximal
edge of the intraocular lens; and fully axially advancing the
plunger rod to expel the intraocular lens from the delivery lumen
into the eye.
25. The method of claim 24, wherein the chamber opens at a hinge,
and wherein the method comprises placing an unfolded intraocular
lens in the open chamber and folding the intraocular lens by
closing the chamber.
26. The method of claim 24, wherein the space is defined by a
recess formed in one wall of the cartridge.
27. The method of claim 26, wherein the recess is defined by a
chamfer formed in the wall only at the proximal end of the
cartridge facing the plunger rod.
28. The method of claim 26, wherein the recess continues as a
longitudinal channel through at least a portion of the lumen, and
wherein the plunger rod is guided along the delivery lumen by the
engagement of the lip within the channel.
29. The method of claim 28, wherein the cartridge further includes
an axially-extending wall portion directed into the chamber
opposite from the channel, wherein the method includes guiding the
lip into the channel upon contact of the engaging head of the
plunger rod with the wall portion.
30. A method of inserting an intraocular lens into an eye,
comprising: providing a cartridge including a chamber for receiving
an intraocular lens and a delivery lumen defining an axis and
extending distally therefrom through an insertion tube; providing a
housing for mounting the cartridge; providing a plunger rod axially
slidable within the housing and having a length sufficient to
extend completely through the cartridge when mounted in the
housing, the plunger rod having an engaging head on its distal end
with bifurcated lips separated by a groove; placing an intraocular
lens within the cartridge with a proximal edge of the lens
extending proximally from the cartridge chamber; mounting the
cartridge with the intraocular lens therein in the housing with the
plunger rod retracted in a proximal direction; positioning the
insertion tube within an eye; axially advancing the plunger rod in
a distal direction such that the bifurcated lips surround the
proximal edge of the intraocular lens and cause the proximal edge
to enter and be captured by the groove prior to the plunger rod
entering the chamber; and further axially advancing the plunger rod
and captured lens into the chamber and thereafter expelling the
intraocular lens from the delivery lumen into the eye.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to apparatus and methods for
inserting an intraocular lens through a small incision into an eye.
More particularly, the invention relates to such apparatus and
methods utilizing a plunger to displace an intraocular lens through
a tubular insertion apparatus, wherein the intraocular lens is
reliably and safely engaged by the plunger.
[0002] An intraocular lens (IOL) is implanted in the eye, for
example, as a replacement for the natural crystalline lens after
cataract surgery or to alter the optical properties of (provide
vision correction to) an eye in which the natural lens remains.
IOLs often include an optic, and preferably at least one flexible
fixation member or haptic, which extends from the optic and becomes
affixed in the eye to secure the lens in position. The optic
normally includes an optically clear lens. Implantation of such
IOLs into the eye often involves making an incision in the eye.
Making the incision as small as possible reduces trauma and speeds
healing.
[0003] IOLs are known which are foldable (deformable) so that the
IOL can be inserted into the eye through an incision smaller than
the diameter of the lens.
[0004] Some of the most generally accepted insertion apparatus
employ a hollow insertion tube having a diameter which permits the
folded IOL to pass freely through the tube without permanent
deformation, and without causing the surgeon to apply excessive
force to overcome friction between the walls of the insertion tube
and the IOL. Excessive force can result in the premature ejection
of the IOL before the surgeon is ready to position it within the
patient's eye. It would be advantageous to provide IOL insertion
apparatus and methods which facilitate the passage of a folded IOL
through the apparatus and the insertion of the IOL in the eye in
easy, effective and controlled manner while avoiding damage to the
IOL and undue trauma to the patient.
[0005] A very useful technique for inserting an IOL into the eye
includes the use of an IOL injector or cartridge, such as the IOL
injector described in Bartell, U.S. Pat. No. 4,681,102, and also in
Brady, U.S. Pat. No. 5,702,402. These IOL injectors include a load
chamber which is connected to an injection tube. The load chamber
includes a lumen for receiving the IOL and is hinged so that the
side walls thereof can be opened like a book. Closure of this lumen
folds the IOL and maintains the IOL in a folded state. The
injection tube includes a small diameter distal tip which is
insertable into the incision within the eye. The cartridge is held
in a handpiece which is coupled to a plunger rod. The plunger rod
moves distally through the load chamber and injection tube to urge
the IOL to pass through the tube and into the eye. The IOL is thus
transferred from the load chamber through the injection tube and
into the eye. As the IOL moves from the load chamber distally
though the injection tube, its folded configuration is further
compressed by a narrowing of the injection lumen. These IOL
injectors simplify the placement of the IOL within the eye and
reduce chances of surgeon error.
[0006] Although the IOL can pass freely through the injection tube,
it must first be secured by the engaging end of the plunger rod.
Because the plunger rod extends fully through the cartridge, its
engaging end must be sized small enough to pass through the
narrowest lumen of the cartridge, at the distal end of the
injection tube. At the same time, the load chamber is relatively
larger than the injection lumen so that the surgeon can easily
place the IOL therein for folding. Therefore, there is a relatively
large space surrounding the plunger rod engaging end as it enters
the load chamber. Additionally, most plunger rods are not rigidly
guided along an axis, but are relatively loosely coupled to a drive
mechanism so that there is some radial play at the engaging end.
Moreover, the IOL and cartridge are made of materials that interact
to produce a coefficient of friction therebetween that must be
overcome when urging the IOL through the tube, even with the
introduction of a lubricating medium. The loose fit of the plunger
rod in the load chamber in conjunction with the friction between
the IOL and cartridge often causes the plunger rod to fail to
engage the proximal edge of the IOL. That is, unless the plunger
rod squarely contacts the proximal edge of the IOL, it may miss
completely or deform the edge and ride up over the IOL, with the
end result that the IOL remains in place while the plunger rod
passes therethrough.
[0007] An intraocular lens insertion apparatus that attempts to
address this problem is disclosed in Brown, et al., U.S. Pat. No.
6,010,510, and includes an injector plunger having a blunt, rounded
tip offset from the centerline of the plunger rod. The offset tip
assures that the tip is biased downward against the bottom of the
cartridge bore to help ensure proper engagement of the intraocular
lens therein. However, there is still a possibility that the
plunger tip might ride underneath or otherwise fail to engage the
intraocular lens.
[0008] There is thus a need for a more effective and safe means for
engaging and displacing an intraocular lens from within an
insertion apparatus.
SUMMARY OF THE INVENTION
[0009] The present invention provides an improved apparatus for
inserting an intraocular lens through an incision into an eye. The
apparatus operates in an environment that is similar to existing
systems, with a cartridge being loaded into a handpiece, and
plunger rod of the handpiece extending through a lumen in the
cartridge to push an intraocular lens from an injection tube of the
cartridge through an incision in the eye. The apparatus of the
present invention provides structure within the cartridge and on
the plunger rod that ensures positive engagement between the
plunger rod and the intraocular lens to more reliably advance the
intraocular lens into the eye in the desired orientation.
[0010] In one particular embodiment, the present invention provides
an intraocular lens insertion apparatus including a cartridge
having a longitudinal lumen extending through an injection tube and
terminating in a mouth on a distal end thereof. An intraocular lens
chamber sized to contain an intraocular lens is defined on a
proximal end of the cartridge and forms part of the lumen. The
intraocular lens has a proximal edge and a distal edge with respect
to the cartridge, and at least a portion of the chamber is
configured with a non-circular cross-section such that, with the
intraocular lens positioned therein, a space along one wall is
created adjacent to the proximal edge of the lens. The apparatus
further includes a housing adapted to hold the cartridge and having
a lumen generally aligned with the cartridge lumen. A plunger rod
having an engaging head is provided that can be linearly displaced
along the housing lumen into the cartridge lumen with a distal lip
of the engaging head aligned with the space. Displacement of the
plunger rod in a distal direction causes the distal lip to enter
the space adjacent the proximal edge of the intraocular lens such
that the engaging head reliably engages the intraocular lens. In a
preferred embodiment, the chamber opens at a hinge so that the
intraocular lens can be folded therein. Also, the engaging head of
the plunger rod may have a forked end defined by the distal lip and
another lip spaced therefrom, with a groove formed therebetween for
capturing the proximal edge of the intraocular lens. The space may
be created by a recess in one wall of the cartridge, the recess
being formed only at the proximal end of the cartridge or extending
longitudinally in a channel. Alternatively, a raised area in one
wall of the cartridge is provided with the proximal edge of the
lens being elevated above the wall to create the space.
[0011] In another aspect of the invention, an intraocular lens
insertion apparatus comprises a cartridge for receiving an
intraocular lens in a proximal chamber. The cartridge defines a
distal injection tube having a lumen in communication with the
chamber along a common axis. The chamber further includes a
generally tubular wall and being configured such that, with the
intraocular lens positioned therein, a space along the wall is
created adjacent to a proximal edge of the lens. The apparatus also
includes a handpiece for mounting the cartridge and having a
plunger rod adapted to be displaced generally along the axis. The
plunger rod includes a bifurcated distal end with a pair of lips
separated by a groove and sized to receive a proximal edge of the
intraocular lens. One lip of the plunger rod aligns with the space
such that displacement of the plunger rod reliably captures the
proximal edge of an intraocular lens within the groove. The space
may be created by a recess in the wall of the cartridge, the recess
being formed only at the proximal end of the cartridge or extending
longitudinally in a channel. Alternatively, a raised area in the
wall of the cartridge is provided with the proximal edge of the
lens being elevated above the wall to create the space. Desirably,
the lumen converges from the chamber distally through the injection
tube such that an intraocular lens is compressed in size upon
passage therethrough. The plunger rod may define an engaging head
on a distal end with a flattened oval-shaped body and an
axially-extending projection on one wide side that terminates in
the lip aligned with the space. Optionally, the cartridge may
include an axially extending wall portion projecting inwardly to
the chamber opposite the wall to help guide the distal end of the
plunger rod such that the one lip extends into the space.
[0012] Another aspect of the invention is a method of inserting an
intraocular lens into an eye including providing a cartridge, a
housing, and plunger rod. The cartridge has a chamber for receiving
an intraocular lens and a delivery lumen defining an axis and
extending distally therefrom through an insertion tube. The
cartridge mounts in the housing, and the plunger rod axially slides
within housing and completely through the cartridge. The plunger
rod has an engaging head on its distal end with an axially
extending lip. The method includes placing an intraocular lens
within the cartridge, the chamber being configured such that a
space is created adjacent a proximal edge of an intraocular lens
positioned therein. The method further includes mounting the
cartridge in the housing with the plunger rod retracted in a
proximal direction, positioning the insertion tube within the eye,
and axially advancing the plunger rod in a distal direction. First,
the lip on the plunger rod enters the space prior to contact
between the engaging head and the proximal edge of intraocular
lens. Further advancement of the plunger rod causes the engaging
head to contact the proximal edge of the intraocular lens. Full
advancement of the plunger rod expels the intraocular lens from the
delivery lumen into the eye. Desirably, the chamber opens at a
hinge and the method includes placing an unfolded intraocular lens
in the open chamber and folding the intraocular lens by closing the
chamber. Also, the chamber may be larger than the delivery lumen
such that intraocular lens is compressed in size upon passage from
the chamber to the delivery lumen. Finally, the cartridge may
include an axially-extending wall portion directed into the
chamber, wherein the method includes guiding the lip into the space
upon contact of the distal end of the plunger rod with the wall
portion.
[0013] In another method, an intraocular lens is positioned within
a cartridge chamber such that a proximal edge of the lens extends
beyond a proximal end of the cartridge. A plunger rod having a
bifurcated engagement head is distally advanced such that the
proximal edge of the lens is captured in a groove of the engagement
head prior to entry of the plunger rod into the cartridge chamber.
The captured lens is then urged through the chamber and from the
injection tube into a patient's eye.
[0014] These and other aspects of the present invention will become
apparent in the following detailed description and claims,
particularly when considered in conjunction with the accompanying
drawings in which like parts bear like reference numerals.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a perspective view of a general insertion
apparatus of the present invention;
[0016] FIG. 2 is a schematic perspective drawing showing the
placement of an insertion tube of the insertion apparatus of FIG. 1
in the eye;
[0017] FIG. 3A is a frontal perspective view of a foldable
cartridge of the present invention;
[0018] FIGS. 3A and 3B are rear perspective views of foldable
cartridges of the present invention;
[0019] FIGS. 4A and 4B are side and rear elevational views,
respectively, of the foldable cartridge of FIG. 3B in its folded
state;
[0020] FIGS. 5A and 5B are side and rear elevational views,
respectively, of the foldable cartridge of FIG. 3B in its unfolded
state;
[0021] FIGS. 6A and 6B are plan and elevational views,
respectively, of a plunger rod of the present invention;
[0022] FIG. 7 is a perspective view of an IOL engaging portion of
the plunger rod of FIG. 6;
[0023] FIGS. 8A-8C are several views of the IOL engaging portion of
FIG. 7;
[0024] FIG. 9 is a perspective view of an alternative IOL engaging
portion of a plunger rod of the present invention;
[0025] FIGS. 10A-10C are several views of the IOL engaging portion
of FIG. 9;
[0026] FIG. 11A is a longitudinal sectional view through an
insertion apparatus of the present invention prior to engagement of
an IOL within the foldable cartridge by the plunger rod;
[0027] FIG. 11B is a view taken a long line 11B-11B in FIG. 11A
showing the rear end of the foldable cartridge with an IOL folded
therein;
[0028] FIG. 11C is a longitudinal sectional view similar to FIG.
11A and showing engagement of a rear edge of the IOL by the plunger
rod;
[0029] FIG. 12A is a longitudinal sectional view through an
insertion apparatus showing an IOL positioned within an alternative
foldable cartridge that creates a space below a proximal edge of
the IOL to facilitate engagement by a plunger rod;
[0030] FIG. 12B is a longitudinal sectional view through an
insertion apparatus showing an IOL positioned within a further
alternative foldable cartridge that creates a space below a
proximal edge of the IOL to facilitate engagement by a plunger rod;
and
[0031] FIG. 13 is a longitudinal sectional view through an
insertion apparatus showing an IOL desirably positioned within a
conventional foldable cartridge so that a proximal edge of the IOL
extends beyond the cartridge to facilitate engagement by a plunger
rod.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] FIG. 1 illustrates an IOL insertion apparatus, shown
generally as 10, in accordance with the present invention. The
apparatus 10 comprises a distal housing 12, a proximal housing 14
and a folding cartridge 16. Distal housing is operatively coupled
to proximal housing 14. Distal housing 12 includes a through
opening 20 through which the folding cartridge 16 can be placed.
Distal housing 12 includes a forward opening 22 through which the
injection tube 24 of folding cartridge 16 extends distally.
Proximal housing 14 includes two oppositely disposed finger
supports 26 which extend outwardly from the outer peripheral
surface 28 of the proximal housing.
[0033] Apparatus 10 also includes a plunger rod 30 which includes
an enlarged proximal end 32 effective to push plunger rod 30
through proximal housing 14, as will be discussed hereinafter.
[0034] Before proceeding to describe the operation of insertion
apparatus 10, a brief description of the operation of folding
cartridge 16 is provided. With reference to FIG. 2, the IOL is to
be placed in the eye 40 into an area formerly occupied by the
natural lens of the eye. With the IOL in its folded position within
apparatus 10, as described below, injection tube 24 is ready for
insertion through an incision 42 in the sclera 44 of eye 40.
Capsular bag 46 protects the posterior segment of the eye 40 and as
one of the eye's constituent parts which is not injured by the
insertion of the IOL with the injection tube 24 inserted within the
eye 40 and the distal end properly positioned, the surgeon advances
plunger rod 30 by manually pushing the plunger rod 30 relative to
proximal housing 14. This action moves IOL distally into injection
tube 24. If needed, IOL can be repositioned in the eye by a small,
bent needle or similar tool inserted into the same position.
[0035] FIG. 2 shows the sclera 44 having an incision through which
the distal end portion of the injection tube 24 is passed.
Alternately, the incision may be made through the cornea. Injection
tube 24 preferably has a sufficiently small cross-section to pass
into the eye 40 through an incision of about 3.5 mm or about 3.0 mm
in the sclera 44. Once IOL is properly positioned in eye 40, and
apparatus 10 is withdrawn from the eye, the incision in the sclera
may be closed, for example, using conventional techniques. After
use, folding cartridge 13, which is made of a polymeric material,
such as polypropylene, preferably is disposed of. Remaining
portions of apparatus 10, which preferably are made of metal, such
as surgical grade stainless steel. may be reused after
sterilization and disinfection. Any suitable material or materials
of construction may be employed in the various components of the
apparatus in accordance with the present invention.
[0036] With reference now to FIGS. 3-5, one specific embodiment of
a foldable cartridge 50 of the present invention will be described.
The foldable cartridge 50 may be used in the manner as described
above for the folding cartridge 16 shown in FIGS. 1 and 2. The
foldable cartridge 50 comprises a generally tubular body 52
defining an axis, with an injection tube 54 extending axially from
a distal end thereof. The injection tube 54 is smaller in exterior
dimension than the tubular body 52, and a convergence section 56 is
provided therebetween. The distal end of the injection tube 54
defines a delivery mouth 58 on the distal end of the foldable
cartridge 50, while the proximal end of the tubular body 52 defines
an opening 60 leading to an IOL load chamber 62. The IOL load
chamber 62 extends substantially the length of the tubular body 52,
and continues in a delivery lumen 64 that gradually reduces in size
through the convergence section 56 and terminates at the delivery
mouth 58. A continuous axial chamber or lumen is thus defined
through the foldable cartridge 50.
[0037] A portion of the tubular body 52 can be folded open as seen
in FIGS. 5A and 5B. Specifically, a pair of planar wings 70a, 70b
projecting radially from the tubular body 52 in its folded state,
as seen in FIGS. 3-4, may be separated so that a half section 74a
of the tubular body 52 opens from another half section 74b about an
axially oriented hinge 76. Desirably, the foldable cartridge 50 is
molded from a polymer such that the hinge 76 may be formed by a
thin connecting portion (i.e., a living hinge) between the two half
sections 74a, 74b. In the folded state of the cartridge 50, the
interior walls of the two half sections 74a, 74b together define
the IOL load chamber 62. In a preferred embodiment, one of the two
half sections 74a, 74b is continuous and fixed with respect to the
tubular body 52, while only the other of the half sections pivots
about the hinge 76. This can be seen best in FIG. 5B.
[0038] With reference to the perspective views of FIG. 3B and the
end elevation of view of FIG. 4B, the opening 60 has an irregular
shape for receiving and folding IOL therein, defined by a pair of
curvilinear sidewalls 80a, 80b and a bottom wall 82 opposite the
radially extending wings 70a, 70b. The bottom wall 82 is
interrupted by a centrally located recess 84. As seen in FIG. 3B,
the recess 84 may continue as a longitudinal channel 86 throughout
all or portion of the tubular body 52, and further may continue
through the delivery lumen 64, as seen in FIG. 3A. The purpose of
the recess 84 will be described below when use of the present
invention is explained. It should be noted that the recess 84
creates a non-circular cross-section for the opening 60 into the
load chamber 62. Specifically, the circular cross-section is
interrupted by the outwardly-directed relief created by the recess
84.
[0039] FIG. 3C illustrates the alternatives foldable cartridge 50'
that is in many ways identical to the foldable cartridge 50, and
thus like elements will be given the same number with a prime (')
designation. The foldable cartridge 50' differs from the earlier
embodiment because it has an axially extending wall portion 90
projecting into the IOL load chamber 62' from one of the wings
70a', 70b'. The function of the wall portion 90 is to help guide a
plunger rod passing through the foldable cartridge 50', as will
become clearer from the usage description below.
[0040] FIGS. 6-8 illustrate one specific embodiment of a plunger
rod 100 of the present invention to be used in conjunction with the
foldable cartridge 50. The plunger rod 100 is a thin, elongate
member having a proximal handle 102, a distal extension rod 104,
and an IOL engaging head 106 on a distalmost end. As seen best in
FIG. 7, the IOL engaging head 106 comprises a neck 108 diverging
from the extension rod 104 to a generally flattened oval body 110
having a longitudinal projection 112 on one of the wide sides
thereof. As best seen in FIG. 8B, the head 106 defines a bifurcated
end 114 wherein a groove 116 is formed between a pair of projecting
lips 118a, 118b. The bifurcated end 114 thus has a generally forked
configuration. One of the lips 118a defines the end of the
projection 112.
[0041] FIGS. 9-10 show an alternative IOL engaging head 120 that
also exhibits a neck 122 diverging from the extension rod 104 and
leading to a somewhat less flattened oval body 124 in comparison to
the body 110 of FIGS. 6-8. As before, the body 124 exhibits a
longitudinal projection 126, and terminates in a bifurcated
(forked) end 128 defining a groove 130 between two lips 132a, 132b.
The less flattened shape of the oval body 124 provides a little
more clearance to the side of the body within the cartridge chamber
to accommodate the fixation members or haptics of the IOL.
[0042] It should be noted that the bifurcated end of either of the
IOL engaging heads described above can take a variety of forms. As
illustrated, the depth of the groove between the two lips is
approximately the same as, or slightly less than, the separation
distance of the two lips. Of course, the depth of the groove can be
more shallow, and can be other than the rounded V-shape as shown.
The idea is to space the lips apart farther than the IOL edge
thickness so that the edge can be captured within the groove.
Further in this regard, the surfaces that contact the IOL are
desirably rounded to prevent scoring or otherwise damaging the
IOL.
[0043] In a specific alternative to the plunger rods illustrated,
the lower lip 118b, 132b of each can be extended axially beyond the
upper lip 118a, 132a, as seen respectively at 134 in FIGS. 8B and
136 in FIG. 10B. These extensions 134, 136 help ensure that the
lower lip 118b, 132b travels underneath the IOL so that the IOL is
captured in the rod grooves 116, 130. The extensions 134, 136 also
serve as a sled of sorts during displacement of the IOL through the
injection tube of the cartridge. The IOL and cartridge are made of
materials that interact to produce a coefficient of friction
therebetween that must be overcome when urging the IOL through the
tube. As mentioned above, this frictional contact is a factor in
causing the plunger rod to fail to engage the proximal edge of the
IOL. By interposing the extensions 134, 136 under the IOL, the
shared contact area between the IOL and cartridge is reduced, and
the metal (e.g., stainless steel) of the extensions acts as a sled
relative to the cartridge material to facilitate movement of the
IOL through the cartridge.
[0044] In use, and with reference to FIGS. 11A-11C, an IOL 140 is
placed within the cartridge 50 (or 50'). Preferably, the cartridge
folds the IOL when the wings 70a, 70b are brought together, but the
present invention is not limited to cartridges that deliver IOLs in
folded configurations. That is, the reader will understand that the
solution described herein to more reliably and safely engage an IOL
with a plunger rod is equally applicable to non-folding
embodiments.
[0045] With reference to the illustrate folding embodiment, the IOL
140 is placed within the half sections 74a, 74b with the wings 70a,
70b separated as seen in FIGS. 5A-5B. Upon bringing the wings 70a,
70b together, the half sections 74a, 74b come together to fold the
IOL and define the IOL load chamber 62, as seen from the end in
FIG. 11B. With the IOL 140 thus properly positioned within the
foldable cartridge 50, the cartridge is positioned within a
handpiece 142. The cartridge 50 is inserted through a longitudinal
slot or opening 144 in the handpiece 142, and advanced distally
until at least the injection tube 54 projects from a distal end 146
of the handpiece. In particular, the opening 144 aligns with a
longitudinal slot (not numbered) ending at a stop surface 148 that
contacts one of the wings 70 to prevent further advancement of the
cartridge 50.
[0046] Once the cartridge 50 is properly positioned within
handpiece 142, the plunger rod 100 (or 120) is axially advanced to
the position shown in FIG. 11A. The plunger rod 100 is generally
aligned with the proximal opening 60 of the cartridge 50, and the
lower lip 118a of the IOL engaging head 106 aligns with the recess
84.
[0047] Further advancement of the plunger rod 100, as indicated by
the arrow 150 in FIG. 11C, causes the IOL engaging head 106 to
capture a proximal edge 152 of the IOL 140. That is, the bifurcated
or forked configuration of the IOL engaging head 16 captures the
proximal edge 152 in its groove 116 (FIG. 8B). To ensure reliable
capture of the IOL 140 by the plunger rod 100, the lower lip 118a
slides through the recess 84 so as to always pass underneath the
proximal edge 152 of the IOL 140.
[0048] As seen in FIG. 11B, the recess 84 creates a space 154
underneath the IOL 140 into which the lower lip 118a extends. In
this regard, the present invention is most suitable for use with
IOLs that can be folded within the cartridge load chamber 62
without substantially deforming into the recess 84, so as to ensure
a sufficient space 154 into which the lip 118a fits. As mentioned
above, the separation distance between the lower lip 118a and the
upper lip 118b is sufficient to always surround the proximal edge
152. In this manner, the proximal edge 152 is guided into the
groove 116, thus capturing the IOL by the plunger rod 100.
Subsequently, the IOL 140 may be distally advanced through the
cartridge 50 and out the delivery mouth 158 into the capsular bag
of the eye.
[0049] As described above, the recess 84 may continue
longitudinally in a channel 86 that extends the entire length of
the cartridge 50. This is seen in the cross sections of FIGS. 11A
and 11C. The channel 86 guides the projection 112 of the IOL
engaging head 106 during passage through the cartridge 50. In
addition, the converging cross-section of the lumen through the
cartridge from the IOL load chamber 62 to the delivery lumen 64 can
also be seen.
[0050] If the cartridge 50' incorporates the inwardly projecting
wall portion 90, seen in FIG. 3C, the IOL engaging head 106 is
constrained in relation to the IOL load chamber 62 such that the
projection 112 remains within the channel 86. In particular, the
distance between the innermost edge of the wall portion 90 and the
bottom wall 82 (see FIG. 4B) of the IOL load chamber 62 is such
that the wall portion may contact the IOL engaging head 106 and
align the lip 118a with the recess. Stated another way, the wall
portion 90 provides additional structure to ensure that the lower
lip 118a passes into the space 154 (FIG. 11B) below the IOL 140.
The relevant dimensions are such, however, that at least a small
amount of clearance remains for uninhibited passage of the IOL
engaging head 106 through the load chamber 62, and subsequently
through the lumen 86. The wall portion 90 is desirably beveled on
its leading edge so that any misalignment of the plunger rod 100
can be corrected prior to the IOL engaging head 106 reaching the
IOL 140.
[0051] FIG. 12A illustrates an alternative foldable cartridge 160
in accordance with the present invention having a cartridge chamber
162 for receiving an intraocular lens 164. As before, the cartridge
160 is adapted to be inserted and secured within a handpiece 166
such that a plunger rod 168 is aligned with and can translate
through the cartridge chamber 162. The plunger rod 168 may be as
described above, with a bifurcated or "scooped" front end for
engaging a proximal edge of the intraocular lens 164 and urging the
lens through the cartridge 160.
[0052] A recessed region 170 is formed on the end of the cartridge
chamber 162 facing the plunger rod 168 that creates a space 172
below the proximal edge of the intraocular lens 164. In the
illustrated embodiment, the recessed region 170 comprises a linear
chamfer, although other recessed configurations such as a
curvilinear chamfer will work. The region 170 is recessed radially
outward from one wall of the chamber 162, in this embodiment a
"bottom wall" opposite the radially extending wings of the folding
cartridge (described above). The bottom wall is typically tubular
and contacts a main portion of the intraocular lens 164, such that
the space 172 is defined radially outward of the bottom wall and
renders the wall non-circular.
[0053] The intraocular lens 164 must be positioned within the
cartridge 160 such that the proximal edge projects over the
recessed region 170. Upon advancement of the plunger rod 168, the
bifurcated end more reliably captures the proximal edge of the
intraocular lens 164 because of the space 172. That is, the lower
lip of the bifurcated end extends within the space 172 and under
the proximal edge of the intraocular lens 164. This configuration
ensures engagement of the plunger rod 168 with the intraocular lens
164.
[0054] FIG. 12B illustrates a further foldable cartridge 180 having
a load chamber 182 for receiving an intraocular lens 184. Again, a
handpiece 186 holds the cartridge 180 such that a plunger rod 188
is aligned with the chamber 182 for advancement of the intraocular
lens 184. To facilitate engagement of the plunger rod 188 with the
proximal edge of the intraocular lens 184, one side of the
cartridge chamber 182 is provided with a ramp or raised area 190.
The intraocular lens 184 is positioned such that the proximal edge
lies on the raised area 190 and is lifted above the side wall of
the chamber 182, and a space 192 is created therebelow. In this
manner, the bifurcated end of the plunger rod 188 more reliably
captures the proximal edge of the intraocular lens 184. The raised
area 190 projects radially inward from one wall of the chamber 162
(i.e., the "bottom wall") and is desirably curved or otherwise
ramped to prevent binding of the plunger rod 188. As before, the
bottom wall is typically tubular and contacts a main portion of the
intraocular lens 184, and the space 192 may be aligned with the
bottom wall or may be defined radially outward of the bottom wall.
The raised area 190 thus creates a non-circular cross-section for
the load chamber 182.
[0055] FIG. 13 illustrates an advantageous arrangement of a
conventional intraocular lens insertion system that facilitates
engagement of a plunger rod 200 with a proximal edge 202 of an
intraocular lens 204. As before, a foldable cartridge 206 having a
chamber 208 for receiving the lens 204 inserts within a handpiece
210. The intraocular lens 204 is deliberately positioned within the
cartridge 206 such that the proximal edge 202 extends beyond the
cartridge in the direction toward the plunger rod 200. The extent
of projection of the proximal edge 202 is shown as distance A, and
is sufficient to promote engagement of the bifurcated end of the
plunger rod 200 with the proximal edge. With this arrangement, a
conventional intraocular lens insertion system can be adapted such
that the plunger rod more reliably engages the lens.
[0056] The present invention provides a cartridge that is designed
to produce a space or recess underneath the proximal edge of the
IOL to facilitate engagement by the plunger rod. It should be
understood, however, that a small space may exist underneath both
the proximal and distal edges of the IOL in its folded
configuration within a conventional circular cross-section load
chamber. A majority of IOLs have a bi-convex optic that includes a
generally planar, disk portion perpendicular to the optical axis,
and oppositely directed convex portions projecting from the disk
portion along the optical axis in the anterior and posterior
directions. In its relaxed, unfolded state, with one of the convex
portions placed on a flat surface, the surrounding edges are
naturally elevated from that surface. When folded within a
conventional load chamber, this edge elevation is reduced somewhat,
but a small space may still exist, as indicated schematically by
the curvature of the folded IOLs in the figures. This can be
visualized by the informal characterization of the folded IOL as
being the shape of a taco shell.
[0057] The height of the space at the proximal edge of the folded
IOL produced by the normal convexity thereof may be up to 0.015
inches, typically between 0.003-0.015 inches. The various cartridge
embodiments of the present invention increase this existent space
to an extent that insures engagement by the plunger rod. For
example, the space created under the IOL in the embodiment shown
FIGS. 11A and 11C may be double the space created by the normal
convexity of the IOL. Specifically, the space created under the
proximal edge of the IOL by the present invention is increased to
between 0.003-0.020 inches, and preferably between 0.005-0.015
inches. In contrast, an exemplary plunger rod includes a bifurcated
engaging head having forwardly directed lips spaced apart by about
0.040 inches, the lips having rounded distal tips having a radius
of about 0.002 inches.
[0058] While this invention has been described with respect of
various specific examples and embodiments, it is to be understood
that the invention is not limited thereto and that it can be
variously practiced within the scope of the following claims.
* * * * *