Intraocular lens

The intraocular lens, whether for implantation in the anterior or posterior chamber of the eye, embodies laterally extending non-radially oriented supporting loops which accommodate by bending compressive forces imposed thereon without flexing or bowing of the lens. The anterior chamber intraocular lens implants are fixated in the angle of the anterior chamber and locate the lens anterior of and in noncontacting relationship with the iris whether extracapsular or intracapsular surgery has been performed. The posterior chamber intraocular lens implants may be fixated in the groove posterior to the iris in an extracapsular eye or in the anterior chamber after penetration of the supporting loop segments through peripheral openings in the iris in an intracapsular eye; with either location of fixation, the lens anatomically replaces the surgically removed lens of the eye.

The present invention relates to intraocular lenses and, more particularly, 
to lenses having stable fixation members providing superior flexibility to 
minimize irritation of tissues and reduce postoperative complications. 
The visual rehabilitation of a patient afflicted with cataract has been a 
controversial topic within the cognoscente for decades. To understand the 
concept of intraocular lens implants, one must first have an intimate 
knowledge of the anatomy of the eye and the characteristics of a cataract. 
Referring to a cross-sectional diagram of an eye, light enters through the 
cornea. The cornea is a clear transparent tissue that serves as a window 
which allows entry of light and provides some amount of focusing 
capability. The light transverses the anterior chamber and penetrates the 
crystaline lens. The lens acts as a major focusing element for the light. 
The light, after being focused by the lens, continues on its path through 
the vitreous and impinges upon the retina. The impinging light is 
transformed into electrical impulses by the reaction of layers of complex 
specialized retinal nerves. The nerves transmit the electrical impulses to 
the brain which translates them into visual sensations. 
The word "cataract" refers to a clouding of the normally clear lens. The 
causes of cataract need not be reviewed except to say that senile cataract 
is an extremely common afflication of patients over the age of sixty and 
leads to varying amounts of significant visual disability. When a cataract 
is present, the light normally penetrating the crystaline lens for 
focusing is impaired by the clouded areas. When the cataract becomes 
severe enough, the only treatment available is surgical removal of the 
cataract which is equivalent to surgical removal of the crystaline lens. 
At the present time, there are no medicinal cures for most patients 
afflicted with cataract. 
Innumerable techniques for cataract removal have been described and are 
currently in practice. The techniques for cataract removal fall into one 
of two broad categories: (1) intracapsular cataract surgery involves 
removal of the entire cataract or crystaline lens together with its 
supporting capsular tissue. Removal is usually accomplished surgically 
with the aid of cryosurgery and the resulting eye is left with the 
vitreous cavity in intimate contact with the posterior surface of the 
iris. (2) extracapsular cataract surgery involves the removal of the 
cataract or crystaline lens interior while leaving the capsular tissue 
either partially or entirely intact within the eye. The important 
distinction between these two categories is that in extracapsular surgery 
the capsular tissue or outer envelope of the lens is left in place to 
separate part or all of the vitreous from the more anterior structures of 
the eye. 
With the surgical removal of the crystaline lens, the resulting eye is 
deficient in focusing power. In the early years of cataract surgery, this 
deficiency of focusing power was corrected by using a thick lens held in 
front of the eye by a spectacle frame. This thick lens did correct the 
focusing power in the central parts of a patient's field of view but was 
very poor in focusing upon objects that were offcenter and toward the 
periphery. As a result, the patients wearing these thick lenses had a type 
of tunnel vision; any objects that were not in the center vision were very 
much distorted or completely absent from view. Because the lenses were 
very thick, the spectacles were very difficult to fit properly, were 
constantly in need of adjustment and the cosmetic effect of the lenses was 
very poor. 
Improvements in visual rehabilitation came with the availability of contact 
lenses. A contact lens is located on the surface of the cornea and 
compensates for the deficiency in focusing power. With the contact lens in 
place, the patient does not have the difficulties of tunnel vision, the 
peripheral vision is very much improved and the distortion attendant the 
thick lenses is absent. The difficulties and detriments attendant contact 
lenses are well known. In example, many people cannot tolerate the feel or 
sensation of a contact lens on their eye; lens hygiene is a constant 
problem and the patient must be meticulous about constant cleaning; 
contact lenses are easily lost. The most significant drawback of contact 
lenses is the fact that a patient with a cataract is very often a patient 
in advanced years who does not have the manual dexterity for proper 
handling of the contact lens. 
A third alternative of visual rehabilitation is the use of an intraocular 
lens implant (IOL). An IOL is a small piece of manufactured plastic that 
is inserted into the eye at surgery. The difficulties enumerated above 
attendant thick lenses and contact lenses are completely eliminated. 
Moreover, the patient has no sensation of the presence of the IOL and if 
the implant is successful, the IOL is in the eye permanently to replace 
the lost focusing power of the removed crystaline lens. 
An intraocular lens falls into one of three broad categories depending upon 
its position within the eye. An anterior chamber intraocular lens is 
placed within the anterior chamber in front of the iris. Its fixation is 
dependent on various styles of loops that are supported in the angles of 
the anterior chamber, whereby the iris tissue is allowed to move freely. 
From a technical standpoint, the anterior chamber IOL's are the easiest to 
implant. The difficulties with prior art anterior chamber IOL's include: 
(1) deficient manufacturing methods which leave rough edges on the implant 
and result in chronic irritation (iritis), elevated intraocular pressure 
(glaucoma) and bleeding within the anterior chamber (hyphema); (2) the 
lens support structure is of solid plastic construction, rather than 
flexible loop construction, which can lead to blockage of the normal 
aqueous flow within the eye (pupillary block glaucoma); (3) the lack of 
sufficient flexibility of the support structure leads to difficulties with 
tenderness on touching of the eye and normal movements during one's daily 
activities can lead to chronic irritation within the eye; (4) the prior 
art anterior chamber IOL's have to be matched in size to the patient's eye 
which increases IOL inventory problems. More importantly, without accurate 
measurements of the patient's eyes, an inflexible or insufficiently 
flexible IOL that is too small results in increased movement of the 
implant that can lead to chronic irritation while an implant that is too 
large tends to distort the eye, cause discomfort and lead to chronic 
irritation. The major advantage of an anterior chamber IOL is that it may 
be used after either intracapsular or extracapsular surgery. 
An iris supported IOL is an implant that depends on iris tissue or a 
combination of iris tissue and capsular tissue for its support. It has 
significant disadvantages because of its lack of uniplanar design, and its 
constant iris contact. As the present invention is not an iris supported 
IOL, further discussion of the prior art pertinent to iris supported IOL's 
need not be undertaken. 
A posterior chamber IOL is inserted behind the iris to position the lens in 
the exact anatomical position of the previously removed cataract or 
crystaline lens. The major disadvantage of prior art posterior chamber 
IOL's is that the cataract must be removed by extracapsular techniques. 
The advantages attendant posterior chamber IOL's in general include: (1) 
fixation at the posterior capsule provides good stability to the eye; (2) 
as no iris fixation is present, the pupil behaves normally; (3) the 
implant is uniplanar and therefore is generally easy to insert without 
damaging other structures; (4) dislocation is rare but if it should occur, 
the implant does not dislocate anteriorly to damage the cornea; and (5) 
the patient is visually rehabilitated as nearly as is physiologically 
possible since the implant is in the exact location as the previously 
removed crystaline lens. 
Historically, the earliest posterior chamber IOL implants were performed by 
Harold Ridley in the late 1940's. The Ridley biconvex lens was about the 
same shape as, but had approximately 1 mm smaller diameter than, the 
normal human lens. Its weight in air was 112 mg, an extremely heavy weight 
for an object to be implanted in the eye. The weight and relatively large 
diameter caused the Ridley lens to exert undue pressure on the ciliary 
body, the annular structure on the inner surface of the eye surrounding 
the lens and including the ciliary muscle and the ciliary process to which 
the zonules are connected. Other adverse side effects occurred: glaucoma 
was noted; in some instances, the lens became loose and fell into the back 
of the eye; and, many cases of downward decentration were noted, wherein 
the lens shifted downwardly so that its axis was no longer centered with 
respect to the pupil. For all of these reasons, the Ridley IOL soon was 
abandoned. 
A related IOL designed by Strampelli for use in the anterior chamber was 
tried in the early 1950's. This IOL seated in the angle of the eye, where 
the cornea and iris are joined. Because of poor peripheral design, the use 
of such IOL's often caused destruction of the endothelium, a very thin 
layer of live cells on the interior of the cornea. This is a very serious 
complication, and use of this form of anglefixated anterior chamber IOL 
soon was stopped. 
Other attempts have been made to accomplish the objective of fixation 
without suturing. The Choyce Mark VIII anterior chamber IOL is a thin, 
generally flat unitary structure having the appearance, when viewed 
frontally, of an elongated rectangle with rounded corners and notched 
ends. The rounded corners seat in the angle and center the planoconvex or 
biconvex optical portion in front of the pupil. The IOL is easy to implant 
and thus has gained acceptance by many surgeons However, cases of CME have 
been noted with these IOL's. Also, because of inflexibility tension is 
placed on the angle, resulting in tenderness and irritability to the eye, 
particularly when rubbed. 
Another form of self-centering IOL was developed by Barraquer, initially 
for anterior chamber use and later adapted for placement in the posterior 
chamber. This IOL includes a pair of hook-shaped flexible loops extending 
from opposite sides of the optical portion. Since one end of each loop is 
free, the loops would flex sufficiently to snap in place. When installed 
in the anterior chamber, the hooks seated in the angle. 
Shearing adapted the Barraquer design for use in the posterior chamber. 
With extracapsular extraction, the hooks may be implaced within the cleft 
of the capsule. However, during implantation the hooks are held under 
tension, and when released may fly up behind the iris and seat directly 
against the ciliary body. Alternatively, with extracapsular extraction, 
the hooks may intentionally be installed against the ciliary body. A 
disadvantage of such an implant is that the hooks continuously exert 
tension on the ciliary body. An increase in the occurrence of retinal 
detachments has been noted amongst patients having such Shearing or 
Barraquer posterior chamber IOL's. It is likely that the retinal 
detachments are associated with the tension exerted on the side of the eye 
in the vicinity of the ciliary sulcus. Furthermore, tenderness also is 
noted with such an IOL when the eye is rubbed. 
A further form of posterior chamber IOL was developed by Pearce. This IOL 
generally resembles a three-bladed airplane propeller, the blades of which 
are inserted into the fornix of the capsule after extracapsular 
extraction. The disadvantage of the IOL is that it is of fixed size and 
therefore the surgeon must take several different sizes into the operating 
room; if the first does not fit, he must remove it from the eye and insert 
another of smaller or larger size. It is also recommended to be sutured 
for centration. The surgical procedure itself is made unnecessarily 
complex. 
Still another form of prior art IOL that is advantageously used with 
extracapsular surgery is the Binkhorst iridocapsular lens. This is a 
variant of Binkhorst's iris clip lens, but it does not have anterior 
loops. The optical portion itself is centered in the pupil with the rim of 
the lens lightly touching the front of the iris. The single pair of loops, 
bent slightly rearward, lie behind the lens and are buried in the 
iridocapsular cleft. After the surgery, the capsule fibroses or develops 
iridocapsular adhesions which embed part of the posterior loops, thereby 
giving extra stability to the implanted lens. 
Various United States patents directed to various types of IOL's include 
the following. U.S. Pat. Nos. 3,906,551 and 3,971,073 illustrate examples 
of iris supported lenses. U.S. Pat. No. 4,079,470 describes an iris 
supported IOL and is particularly directed to the material of lenses and 
coatings therefor. U.S. Pat. No. 4,077,071 is directed to increasing the 
bouyancy of an IOL implant. U.S. Pat. No. 4,170,043 is also primarily 
directed to coatings for IOL implants. U.S. Pat. No. 4,168,547 is related 
primarily to materials for IOL implants. U.S. Pat. No. 4,110,848 is 
directed to an only slightly flexible posterior chamber IOL implant which 
must be used in an extracapsular eye. U.S. Pat. No. 4,244,060 describes a 
posterior chamber IOL implant which employs numerous filaments for 
supporting the implant. U.S. Pat. No. 4,092,743 is directed to a posterior 
chamber IOL implant of solid loop material which has no flexibility and 
the implant can only be used in an extracapsular eye. A variant of the 
invention, an anterior chamber IOL implant is depicted in FIG. 7 and 
illustrates an implant presently in production and in use. Either of the 
types of implants described depend upon three point fixation which method 
of fixation has been severely criticized in the scientific literature 
because of an often resulting tilting of the lens. Moreover, with three 
point fixation, one of the ends of the implant can work its way through a 
peripheral iridectomy and lead to a very unstable lens having only a two 
point fixation. Little flexibility is available from the implants 
described and the problems resulting therefrom and enumerated above occur. 
U.S. Pat. No. 4,174,543 describes an anterior chamber IOL implant, which 
implant is intended to have flexible support members. However, the 
configuration and orientation of the support members either preclude 
flexibility in response to forces exerted radially inwardly within certain 
angular orientations or within certain relatively significant arcs, 
depending upon the configuration under examination. The limitations of 
flexibility of the support members and the resulting lack of 
compressibility of the proximal segments is a severe limitation on the 
size of the eye in which any given IOL may be implanted. 
The intraocular lens implants embodied by the present invention, whether 
for implantation in the anterior or posterior chamber, incorporate 
supporting legs or loops of one or more segments At least a segment of 
each loop is curved and none of the segments of any loop is coincident 
with a radial of the lens. Thereby, any compressive force exerted radially 
by the eye upon a point along opposed supporting loops will be 
accommodated by a bending of one or more segments of each supporting loop. 
The anterior chamber intraocular lenses may be used after either 
intracapsular or extracapsular surgery and the points of fixation of the 
supporting loops are supported in the angle of the anterior chamber. The 
posterior chamber intraocular lenses are inserted posterior to the iris in 
the exact anatomical position of the previously removed cataract, which 
cataract may be removed by either intracapsular or extracapsular surgery. 
The points of fixation of the supporting loops are entirely posterior to 
the iris and anterior to the remaining lens capsule in an extracapsular 
eye. In an intracapsular eye, at least one of the supporting loops is 
maneuvered from the posterior chamber to the anterior chamber through a 
peripheral opening of the iris and fixated in the peripheral portion of 
the anterior chamber. Manipulation holes or grooves are provided in the 
proximal segment of the supporting loops and in the lens portion to 
provide grip for pronged tip forceps prior to and during fixation. The 
configuration of the supporting loops permit a single size of anterior 
chamber intraocular lens or posterior chamber intraocular lens to fit any 
eye size. 
It is therefore a primary object of the present invention to provide 
supporting loops for both anterior and posterior chamber intraocular 
lenses which are sufficiently flexible to accommodate normal imposed 
compressive forces without any discomfort. 
Another object of the present invention is to provide a single sized 
anterior or posterior chamber intraocular lens which may be used in any 
sized eye within a large range of eye sizes. 
Still another object of the present invention is to provide an anterior and 
posterior chamber intraocular lens implant which has a maximum width of 
six millimeters, the diameter of the lens itself. 
Yet another object of the present invention is to provide an anterior or 
posterior intraocular lens implant which has a maximum dimension of 131/2 
millimeters and which is compressible to a dimension of 11.5 millimeters 
with no lens bowing anteriorly or posteriorly. 
Yet another object of the present invention is to provide anterior and 
posterior chamber intraocular lens implants which are physically free of 
the iris and permit normal pupillary movement. 
A further object of the present invention is to provide a true posterior 
chamber intraocular lens with no dependence on the pupillary sphincter and 
useable after either intracapsular or extracapsular cataract removal. 
A still further object of the present invention is to provide a posterior 
chamber intraocular lens which may be fixated within the anterior chamber 
peripherally. 
A yet further object of the present invention is to provide a posterior 
chamber intraocular lens which is fixated entirely posterior to the iris 
and anterior to the remaining lens capsule in an extracapsular eye. 
A yet further object of the present invention is to provide a posterior 
chamber intraocular lens implant which is useable in any sized 
intracapsular or extracapsular eye. 
These and other objects of the present invention will become apparent to 
those skilled in the art as the description thereof proceeds.

Referring to FIG. 1, a normal eye will be briefly described. Cornea 12 is a 
clear transparent tissue which acts as a transmissive element for light. 
It also has some capability for focusing the transmitted light upon the 
retina (not shown). The light transmitted through the cornea passes 
through anterior chamber 14 and the fluid disposed therein and impinges 
upon a crystaline lens 16. The lens acts as a major focusing element for 
the light penetrating therethrough upon the retina. A fluid known as 
vitreous humor is a light transmitting medium intermediate the lens and 
the retina. Lens 16 is encased within a capsule 18. Iris 20 is disposed 
anterior of lens 16 and serves in the nature of a diaphragm to regulate 
the amount of light impinging upon the lens. 
When cataract occurs, clouded areas form within the lens These clouded 
areas affect the transmissivity of light therethrough and impair sight. 
When the cloud becomes sufficiently severe, the only treatment available 
is surgical removal of the lens itself. Such removal is referred to as 
extracapsular cataract surgery (extracapsular eye) when capsule 18 remains 
either partially or entirely intact within the eye. Removal of the lens 
together with the supporting capsular tissue or capsule 18 is referred to 
as intracapsular cataract surgery (intracapsular eye). 
FIGS. 2 through 7 illustrate various anterior chamber intraocular lens 
implants and FIGS. 9 and 10 illustrate a posterior chamber intraocular 
lens implant, any of which may be used to replace a lens 16 removed by 
either intracapsular or extracapsular cataract surgery. Each of these 
implants includes an optical portion having a plano-convex surface with 
the convex surface facing anteriorly. Nominally, the optical portion is 6 
millimeters in diameter. Supporting loops having a nominal width of 0.25 
millimeters extend in generally diametrically opposed directions from the 
optical portion. These supporting loops and the optical portion may be of 
one piece construction or separate pieces with the supporting loop firmly 
inserted into the optical portion at a predetermined angle and 
orientation. The major dimension across the implant diameter is nominally 
13.5 millimeters and the width is no more than that of the lens, 6 
millimeters. The material of the implants may be of polymethylmethacrylate 
or other nonabsorbable nontoxic sterile material. 
Referring to FIG. 2, there is shown a lens portion 30 retained in place by 
supporting loops 32 and 34. The supporting loops are mirror images of one 
another in both configuration and size. Each segment 36 is curved and 
extends from a point essentially tangential to optical portion 30. Segment 
38 is curved interiorly toward the optical portion from between fixation 
points 40 and 42, the latter also being the junction with segment 36. Both 
fixation points are smoothly rounded to preclude abrading and irritating 
the point of contact with the eye. By inspection, it will become apparent 
that any compressive force imposed upon any two points of fixation will 
result in bending of any intermediate segments and compliance with any 
such imposed compressive force does not depend upon compression or 
elongation of a segment along its longitudinal axis. 
FIG. 3 illustrates a lens portion 44 having supporting loops 46, 48 
extending tangentially from diametrically opposed locations on the lens 
portion. Since the supporting loops are identical but reversely oriented, 
a description of one will apply to the other. Segment 50 of supporting 
loop 46 extends tangentially from the edge of lens portion 44 and 
thereafter curves somewhat concentrically with the lens portion through a 
substantial arc whereafter it extends exteriorly in general parallel 
laterally offset relationship with a radial of the lens portion bisecting 
the curved part of the segment. Segment 52 extends perpendicularly from 
the extremity of segment 50 for a distance approximately equal with the 
diameter of the lens portion. The junction between the two segments and 
the extremity of segment 52 are curved smooth surfaced and define fixation 
points 54, 56. 
By inspection, it will become apparent that any compressive force imposed 
intermediate the fixation points of supporting loop 46 and 48 will result 
in bending of two or more of the segments. Moreover, compliance with such 
compressive force is not dependent upon compression or elongation of any 
segment along its longitudinal axis. It may be noted that upon application 
of a compressive force intermediate fixation points of supporting loops 46 
and 48, some counter-clockwise rotation of lens 44 may occur. Such 
rotation has no effect upon the optics of the lens portion and the patient 
will be unaware of it. 
FIG. 4 illustrates a lens portion 58 having diametrically opposed 
supporting loops 60, 62. Each supporting loop includes a pair of 
exteriorly oppositely curved segments 64, 66. The segments are terminated 
by bulbous ends which serve as fixation points 68, 70, respectively. The 
configuration of the segments of supporting loops 60 and 62 provide 
compliance with any compressive force exerted intermediate any two 
fixation points by bending of the intermediate segments. The overall 
flexibility of this implant may be somewhat less than that of the implants 
described above because of the diametrically opposed junctions in 
combination with the radially centered disengaging orientation of each 
pair of segments. 
The implant illustrated in FIG. 5 is a direct variant of that shown in FIG. 
4. Herein, lens portion 72 includes a pair of diametrically opposed 
supporting loops 74, 76. Each loop includes segments 78, 80 diverging from 
a junction. Each segment includes a curved section and a straight section 
extending from the extremity of the curved section and along a line 
parallel to and offset of a radial of the lens portion passing through the 
junction of the relevant supporting loop. The bulbous end of each straight 
section of segments 78, 80 serves as a fixation point 82, 84. 
FIG. 6 illustrates an anterior chamber intraocular lens implant which 
includes a lens portion 82 retained in place by a supporting loop 32 of 
the type described with respect to FIG. 2. A second supporting loop, 
located in diametrically opposed relationship thereto may be of the 
configuration of supporting loop 60 shown in FIG. 4 or supporting loop 74 
shown in FIG. 5. 
FIG. 7 illustrates an anterior chamber intraocular lens having a lens 
portion 84 supported by a supporting loop 46 of the type described with 
respect to FIG. 3. The diametrically oriented opposed supporting loop may 
be either supporting loop 60 shown in FIG. 4 or supporting loop 74 shown 
in FIG. 5. 
Referring to FIG. 8, there is shown an anterior chamber intraocular lens 
implant 90 located within eye 10. The selection of implant 90 may be any 
one of the type illustrated in FIG. 2 through 7, the selection of which is 
dependent upon various criteria not presently germain. To insure a 
noncontacting relationship between the implant and iris 20, a vault of 
approximately 0.5 millimeters is formed between the planoposterior surface 
94 of lens portion 92 and posterior surfaces 96, 98 attendant the 
extremities of supporting loops 100, 102. As illustrated, implant 90 is 
supported by the fixation points 104, 106 in angles 108, 109 within the 
anterior chamber. It may be noted that eye 10 is illustrated as having 
undergone intracapsular cataract surgery although it is to be understood 
implantation could as easily have been accomplished had the eye undergone 
extracapsular cataract surgery. 
Referring jointly to FIGS. 9 and 10, there is shown a posterior chamber 
intraocular lens implant 110. The structure of this implant permits 
implantation within the posterior chamber of any sized eye and 
irrespective of whether the cataract has been removed by extracapsular or 
intracapsular surgery. A pair of supporting loops 112, 114, extend 
tangentially in opposed directions from the perimeter of lens portion 116. 
In the embodiment illustrated, the supporting loops are mirror images of 
one another and only one of them will be described in detail. Supporting 
loop 112 includes a segment 118 which is curved interiorly toward lens 
portion 116. A further segment 120 extends from the extremity of segment 
118 and is folded back upon it; this segment is also curved interiorly 
toward lens portion 116 and may be concentric therewith. It may be curved 
as shown to provide an infinite number of fixation points. As particularly 
illustrated in FIG. 10, supporting loops 112 and 114 may lie in the same 
plane as the plane of the plano-convex lens portion 116. Alternatively, 
the supporting loops may be set at an angle of approximately 10.degree. 
with respect to the posterior plane of the lens portion, as illustrated in 
FIG. 12. 
The fixation of implant 110 in an extracapsular eye is particularly 
illustrated in FIG. 11. Herein, there is depicted an eye 122 upon which 
extracapsular surgery has been performed leaving posterior capsule 126. 
Supporting loops 112, 114, extending from lens 116 of implant 110 are 
fixated anterior to capsule 126 within a sulcus or groove 130 posterior of 
iris 20 and at the pupillary periphery; it does not affect pupillary 
movement. 
FIG. 12 illustrates a posterior chamber intraocular lens implant 140 having 
supporting loops 142, 144 extending in diametrically opposed directions 
from lens 146. The loops extend forwardly, that is toward the convex 
surface of the lens, at an angle of approximately 10.degree. with respect 
to the plane defined by the planar surface of the lens. Implant 140 is 
shown fixated within an eye 148 which has undergone intracapsular surgery. 
The segments are either fixated posteriorly with the aid of a 
non-absorbable fixation suture through iris tissue in the periphery or the 
segments are manipulated from the posterior chamber to the anterior 
chamber through a peripheral iridotomy for fixation in the anterior 
chamber. Segments 120 (see FIG. 9) of supporting loops 142, 144 have been 
maneuvered from the posterior chamber to the anterior chamber through a 
peripheral opening of the iris (iridotomy or iridectomy) and fixated in 
the peripheral portion of the anterior chamber. In either case, the 
optical portion of the implant remains in the posterior chamber and the 
points of fixation are at or in proximity to the pupillary periphery to 
avoid affecting the pupillary movement. It is to be understood that the 
description above is also applicable to posterior chamber intraocular lens 
implants in which the supporting loop are not angulated. 
As particularly noted in FIG. 9, apertures 150 are disposed in segments 118 
of the supporting loops; alternatively, the apertures may be replaced by a 
radially inwardly oriented depression or groove 152, as shown on segment 
118a. These apertures or grooves, in combination with apertures 154 in the 
lens, are engageable with pronged tips of forceps to permit compressing of 
the supporting loops to ease manipulation of the implant into the 
posterior chamber. 
While the posterior chamber intraocular lens implant is illustrated in 
FIGS. 11 and 12 as being generally vertically oriented (note FIG. 9), 
horizontal orientation is possible Moreover, horizontal orientation for 
intracapsular eyes positions segments 120 such that penetration through 
the iris occurs at the ten and two o'clock positions of the eye. 
Upon fixation of the posterior chamber intraocular lens implant, 
essentially all of segments 120 are disposed in the anterior chamber while 
essentially all of segments 118 are disposed posterior of iris 20 such 
that the junction between the segments is coincident with the respective 
peripheral openings in the iris. 
A primary advantage of the posterior chamber intraocular lens implant 
described with particular reference to FIGS. 9 through 12 is that it 
provides a single sized uniplanar implant that can be used in any sized 
eye. Furthermore, it retains all of the advantages of a posterior chamber 
intraocular lens implant and is also suitable for use in an eye which has 
undergone either extracapsular surgery or intracapsular surgery. Moreover, 
the disadvantages inherently attendant either anterior chamber intraocular 
lens implants or iris supported lenses are avoided. 
While the principles of the invention have now been made clear in an 
illustrative embodiment, there will be immediately obvious to those 
skilled in the art many modifications of structure, arrangement, 
proportions, elements, materials, and components, used in the practice of 
the invention which are particularly adapted for specific environments and 
operating requirements without departing from those principles.