Abstract:
A device, providing enlargement and preventing collapse, of the pupil of the eye, during an ophthalmic surgical procedure. The device made of resiliently flexible material and configured as a ring, comprises plurality of notches at corners and flanges at sides. Notches engage the pupillary margin at different parts, pushing them apart, causing enlargement of the pupil. Consecutive flanges lie above and below the iris and bend the pupillary margin at the notches. The enlarged pupil allows a wide view of the structures deeper to the pupillary plane, previously obscured due to a small pupil. When the ring is manually expandable or self-expandable it is made of a combination of shape retaining and shape memory material that is selected from the group consisting of a self-enlarging material, a self-healing material, a self-reconfiguring programmable material, a biodegradable material, and/or drug-eluting material.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 14/379,684, filed Aug. 19, 2014, which is a §371/U.S. National Phase of International Patent Application No. PCT/IN2013/000457, filed Jul. 23, 2013, and claims the benefit of (i) the aforementioned U.S. and international patent applications; (ii) Indian Provisional Patent Application No. 225/KOL/2013, filed Feb. 27, 2013, (iii) Indian Provisional Patent Application No. 228/KOL/2014, filed Feb. 24, 2014, (iv) Indian Provisional Patent Application No. 841/KOL/2014, filed Aug. 13, 2014, and (v) Indian Provisional Patent Application No. 1319/KOL/2014, filed Dec. 17, 2014. The disclosures of all of the foregoing patent applications are incorporated by reference herein in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention is in the field of ophthalmic surgery and relates to an improvement in the device for mechanical enlargement or dilation of the pupil of the eye during surgery. 
         [0003]    During phacoemulsification surgery and vitreo-retinal surgery, when the pupil does not dilate with medicated drops, a device is required for mechanical enlargement of the pupil. Such a device has to maintain the pupil in the enlarged state and prevent it from collapsing for the entire duration of the surgery. Removal of the device returns the pupil to an unenlarged state to preserve its function and cosmesis. Eyes with non-dilating pupils are often also associated with floppiness of the iris, which poses additional difficulty during surgery. 
         [0004]    In phacoemulsification surgery for cataract, a 1.6 to 2.8 mm incision in the side of the cornea is required to insert a phaco probe. Smaller incisions result in secure and astigmatically neutral wounds translating into better visual outcomes. 
         [0005]    Vitreo-retinal surgery requires 0.6 mm or smaller incisions in the sclera to insert instruments into the eye. Since a corneal incision is not required, such an incision, only to insert a pupil-dilating device, should be as small as possible. 
         [0006]    Current devices in use for pupillary dilation require a 2.2 to 2.5 mm incision for insertion into the eye. They snag the incision because of gaps or pockets at the corners, which have a biplanar structure with a top and bottom part. Such snagging makes removal of the device difficult and causes damage to the cornea. They require precise alignment to engage the pupillary margin into the small narrow wedge shaped gaps or pockets at the corners. This is particularly difficult because the surgeon has a top view and the device itself obscures view of the narrow gap, which is at the side of the device. The gaps or pockets have two structural planes having an upper and lower part making the corners thick and bulky. The gaps or pockets hold the pupillary margin and iris tissue passively and the pupillary margin can easily disengage during surgical manipulations. 
         [0007]    Such continuous ring devices have been disclosed in U.S. Pat. No. 8,323,296, Dec. 4, 2012 by Malyugin, US Patent Application publication 2012/0269786, Nov. 15, 2012 by Dusek and US Patent Application publication 2013/0096386, Apr. 18, 2013 by Christensen &amp; Colvard. 
         [0008]      FIG. 1  shows an enlarged diagrammatic top perspective of the ring of the type disclosed in Malyugin U.S. Pat. No. 8,323,296, Dec. 4, 2012. The Malyugin ring  1  has a square configuration with four helical loops  2 ,  3 ,  4  and  5  formed by one complete turn of the strand and separated by sides  6 ,  7 ,  8  and  9 . The two ends  10  and  11 , of the ring have indented portions and are butt attached to each other by adhesive at the joint  12 . Each loop has a wedge shaped gap  13  and  14 , which faces the periphery of the ring, to receive and capture the iris tissue. The ring  1  maintains the pupil in an extended position while the central opening  15  provides a wide viewing area during surgery. 
         [0009]      FIG. 2  shows an enlarged diagrammatic side view of ring of the type disclosed in Malyugin U.S. Pat. No. 8,323,296, showing iris tissue  16  within the wedge shaped gaps  13  and  14  of the loops. The side  9  connects the bottom part of gap  13 , which is at one plane, to the top part of gap  14 , which is at another plane. 
         [0010]      FIG. 3  shows an enlarged diagrammatic top plan of the modified ring of the type disclosed in Dusek US Patent Publication 2012/0269786. The Dusek ring  17  has four sides  18 ,  19 ,  20  and  21 . Side  20  has the end butt joint  22  where a drop of adhesive secures the ends  23  and  24 . Side  19  is perpendicular to side  20 . The sides are joined by a corner portion  25  which has three distinct bends, namely, a first obtuse bend  26  (essentially 135° inward and to the left as viewed in  FIG. 3 ), second return bend  27  (essentially 180° inward and then down away from the viewer and then toward the right as viewed in  FIG. 3 ), and a third obtuse bend  28  (essentially 135° up and to the left as viewed in  FIG. 3 ). Corner portions  29 ,  30  and  31  are identical to corner portion  25 . 
         [0011]      FIG. 4  shows a perspective view of the ring of the type disclosed in Christensen &amp; Colvard US Patent Publication 2013/0096386. In the described embodiment of this disclosure, ring  32  has a square formation with rounded corners  33 ,  34 ,  35  and  36 . At each corner, there is a top plate  37 , which forms generally one plane of the ring and there is a bottom plate  38 , which forms generally a second plane of the ring. These planes are generally above and below the primary plane of the ring formed by connecting limbs  39 ,  40 ,  41  and  42 . Together, the outer periphery of the top plate and the bottom plate at each corner form a lip feature, which is the entrance of the pockets  43 ,  44 ,  45 , and  46  that contain a portion of the iris, which is supported in an open configuration. 
         [0012]    Though discontinuous ring devices have been disclosed in U.S. Pat. No. 5,163,419, Nov. 17, 1992 by Goldman, U.S. Pat. No. 5,267,553, Dec. 7, 1993 by Graether, U.S. Pat. No. 6,620,098, Sep. 16, 2003 by Milverton and U.S. Pat. No. 6,648,819, Nov. 18, 2003 by Lee, these devices have not found acceptance because of larger incision size required, cumbersome manipulations involved and loose engagement. 
         [0013]    A device, which can expand from a smaller contracted state, would be easier to place within the smaller non-dilated pupil. Such devices have been disclosed in U.S. Pat. Nos. 4,782,820, 5,299,564 &amp; 5,441,045 and US patent application publication No. US 2013/0267988 A1. All these devices have an outward facing cup or groove which receives the pupil margin. This outward facing cup or groove has a ‘C’ shaped cross section aligned perpendicular to the general plane of the device. This results in a bulky device with a larger vertical profile. This is not desirable since space in the anterior chamber of the eye is limited. Moreover, these devices do not provide controlled engagement and enlargement of the pupil margin. 
       OBJECTS OF THE INVENTION 
       [0014]    A principal object of the present invention is to provide a device to enlarge the pupil of the eye, which requires a very small incision for insertion into the eye. Another object of the invention is to provide a device with a mechanism to engage the pupillary margin that will not snag the incision during insertion or removal. A further object of the invention is to provide a device, with an easier mechanism to engage the pupillary margin that does not require precise alignment of the pupillary margin into the narrow wedge shaped gaps or pockets at the sides of the device. A further object of the invention is to provide a device, with corners that can engage the pupillary margin but are slim and strictly in the same plane of the device. A further object of the invention is to provide a device, which not only enlarges the pupil, but also remains securely, yet reversibly fastened to iris tissue so that surgical manipulations do not lead to its disengagement. A further object of the invention is to provide a device that reduces floppiness of the Iris, which is often associated with non-dilating pupils. 
         [0015]    Another object of the invention is to provide a device that requires a very small incision for insertion and removal. A further object of the invention is to provide a device that will not snag the incision during insertion or removal. A further object of the invention is to provide a device with corners that can engage the pupillary margin but are slim and generally in the same plane of the device. 
         [0016]    Another principal object of the present invention is to provide a device that can engage the pupil margin in a small contracted state and then be expanded in a controlled manner to a larger expanded state enabling controlled expansion of the pupil. Another object of the invention is to provide a device that can be contracted to a smaller state to facilitate insertion of the device through a small incision. A further object of the invention is to provide a device that can be contracted to a smaller state for compact nesting within a delivery or extraction system. A further object of the invention is to provide a device that can be easily removed through a small incision. A further object of the invention is to provide a device that has a very thin profile. 
         [0017]    Another principal object of the present invention is to provide a device that can engage the pupil margin in a small contracted state and then be expanded in a controlled manner to a larger expanded state enabling controlled expansion of the pupil. Another object of the invention is to provide a device that can be contracted to a smaller state to facilitate insertion of the device through a small incision. A further object of the invention is to provide a device that can be contracted to a smaller state for compact nesting within a delivery or extraction system. A further object of the invention is to provide a device that can be easily removed through a small incision. A further object of the invention is to provide a device that has a very thin profile. 
       SUMMARY OF THE INVENTION 
       [0018]    The present invention is a device to enlarge and prevent collapse, of the pupil of the eye, during surgery. The notches and flanges, on the same plane of a continuous or discontinuous ring, used to engage the pupillary margin, is the novelty of the present invention. The notches are at corners and alternate with side elements or flanges along the perimeter of the ring. The notches are open outwards with a blind receptacle inwards. Notches engage different parts of the pupillary margin and push them apart, resulting in sustained enlargement of the pupil. The flanges are formed from broad loops of the strand and are directed outwards. 
         [0019]    The device is made of a strand of any resiliently flexible material. Thermally treated 5-0 nylon suture (0.10 to 0.12 mm) is such. Notches temporarily straighten as they pass through the incision allowing the device to be inserted through a very small incision. The device, having no gaps or pockets, being entirely disposed in a single plane, passes through the incision without snagging. The device bends the pupillary margin and iris at the notches and flanges, somewhat like a paper clip, creating a secure engagement. The iris being flexible, can tolerate such bending without any damage. The flanges lying in front of the iris reduce its floppiness by restricting the billowing effect. 
         [0020]    Within the scope of the same inventive concept, variations in design are necessary, to allow the surgeon choices depending on the nature of the surgery, size of the eye, depth of the anterior chamber, associated co morbidity, size of incision, initial pupil size, desired pupil size etc. Variations in design are also necessary to suit different manufacturing capabilities. 
         [0021]    The continuous form of the ring is in the form of a polygon with at least three sides and can be with or without a joint. The ends are joined by knotting or tying of the ends, or by chemical, thermal or ultrasonic bonding of the ends or by any other method. When made by molding, stamping or other methods there is no joint. The discontinuous form of the ring has at least three sides, two corners and four notches. This form requires a much smaller incision for insertion. 
         [0022]    In one of the form of the invention, the ring has alternate side elements or flanges gently tilted backwards, enabling easy tucking of the flange under the iris. 
         [0023]    Notches are formed by an inward loop of the strand at the corners or by an inward loop of the strand between two outward digit shaped protruded loops of the strand. In one form of the invention, the corners of the ring have two adjacent notches. 
         [0024]    Positioning holes on the device help in manipulations of the device. When the device is made of expansible material, it enlarges to a larger size after insertion. 
         [0025]    The ring device is configured to adapt one or more selected configurations from a folded, extended or deformed configuration, allowing insertion through small incisions. 
         [0026]    The present invention further includes an expandable device to enlarge and prevent collapse of the pupil of the eye during surgery, wherein the novelty of the device is that it has a contracted state, multiple intermediate incrementally expanded states and a fully expanded state with pupil engaging parts aligned in the same general plane of the device resulting in a very thin profile. The device is made of a single strand or multiple pieces of single strand of resiliently flexible material. This strand may be solid or tubular. The device is a continuous ring formed either by interconnecting the two ends of a single strand or by interconnecting ends of the multiple pieces of single strand in series. The continuous ring forms a polygonal shape with at least three sides. At least one of the sides of the polygonal shape is expandable. Expansion of one or more connecting parts increases the circumference and the radial dimension of the device. Increase in radial dimension of the device causes the engaging parts to push the pupil margin radially away from the center. 
         [0027]    The device has plurality of pupil margin engaging parts and supporting parts. The pupil margin engaging parts are at the corners of the polygonal shape and the supporting parts form the sides of the polygonal shape. The pupil margin engaging parts and the supporting parts are disposed in the same general plane of the device. The pupil margin engaging part is a notch, formed by a short acute inward bend towards the center of the ring, a return outward bend followed by a third acute bend of the strand. At least one supporting part has an interlocking slip joint and is expandable. In the form of the device made of a tubular strand, such a slip joint is a telescoping type. In the form of the device made of a solid strand the slip joint is a non-telescoping sliding joint type. In one form of the device, the ring is made of a single strand with first end and second end interconnected at a supporting part in a manner that they can slide in relation to each other to result in an expanded state of the ring. In another form of the device, the ring is made of multiple single strand units in series with interconnected ends at more than one supporting part that can slide in relation to each other to result in an expanded state of the ring. In this form of the device, all the interconnected units are disposed in the same general plane of the device. In this form of the device, the second end of one unit and the first end of the consecutive unit in the series are interconnected. In one preferred form of the device, the ring is made of four single strand units in series with interconnected ends and has a substantially square configuration. 
         [0028]    In the form of the device made of single solid strand or multiple pieces of single solid strands in series, the strand has a circular cross section throughout except at the segment proximal to an end up to completion of the preceding notch. In this segment, immediately after the preceding notch the strand gradually flattens up to the end to form a thinner and broader leaf. In this segment, the cross section of the strand gradually changes from circular to elliptical to a narrow rectangle. Each leaf has a hole, gap or slit close to the end. At a sliding joint, the first end of a unit is threaded through the hole in the second end of the preceding unit and the second end of the preceding unit is threaded through the hole of the first end of the consecutive unit, resulting in an interlocking sliding joint. As the supporting part is expanded, the broader leaf may roll at the sides as it snugly fits in the hole of the other unit. Interconnecting the ends of consecutive units in such manner creates a continuous chain. Interconnecting the first end of the first unit and the second end of the last unit creates a continuous ring. A discontinuity created in the margin of the hole of either the first end of the first unit or the second end of the last unit allows this interconnection to be completed. After the continuous ring is formed, the discontinuity in the margin of the hole is closed with glue. 
         [0029]    In the form of the device made of a tubular strand, the strand has a polygonal cross-section. The area of the polygonal cross section varies in different parts. A telescopic slip joint interconnects the ends at the expandable supporting part. The polygonal cross section restricts axial rotation of the strands at the joint. In one preferred form, the tubular strand has a square cross section. An inward flange or tapering of the outer tube and an outward flange or flaring of the inner tube limits the extent of expansion at the supporting part. 
         [0030]    The present invention further includes an expandable device to enlarge the pupil of the eye during surgery. The novelty of the device is in the use of shape retaining pliant material, either wholly or partly in combination with resilient shape memory parts, to provide controlled expansion of the device from a deformed state to an undeformed state and vice versa. The shape memory resilient parts, when present, allow shape recovery and the shape retaining pliant parts allow controlled expansion of the device. The device comprises a strand formed as a ring at least partially enclosing a central space with plurality of pupil margin receiving parts connected by supporting parts shaped as flanges. The ring may be open or closed with at least three sides. When closed the ring forms a polygonal shape. The pupil margin engaging parts are at the corners and the supporting parts shaped as flanges are at the sides of the polygonal shape. In one embodiment of the invention, at least one of the pupil margin engaging parts at the corners is resiliently flexible and has shape memory and at least one of the supporting parts forming a flange, is pliant and shape retaining. Other embodiments have varying combinations of shape memory resiliently flexible pupil margin engaging parts at the corners and shape retaining supporting parts forming flanges. In another embodiment, the entire device is made of only shape retaining pliant material. Shape retaining and pliability properties of the pliant parts is such that manual instruments, automated instruments, other external or internal stimuli or forces can bend or straighten the pliant parts of the device inside or outside the eye but the constricting or dilating forces of the pupil of the eye cannot bend or straighten these parts. In other words, the shape retaining strength of the pliant parts is more than the constricting or dilating forces of the pupil margin. Each corner portion includes a blind end, a first limb connecting one flange to the blind end on one side, and a second limb connecting the next flange to the said blind end on an opposite side, to form a receiving means. In one embodiment, the blind end, the first limb and the second limb of a corner portion are all disposed in the same plane. In one embodiment, all corner portions are disposed in the same plane. In one embodiment, each flange is disposed entirely in a single plane. In one embodiment, all flanges are disposed in the same plane. In one embodiment, all corner portions and all flanges are disposed in the same plane. This embodiment has a very thin profile in the undeformed state. In different embodiments, in the contracted state, one or more pliant or resilient parts or both are bent or folded in a manner to reduce at least one radial dimension of the device. In some contracted states, the device remains in a thin single plane without any overlap of parts. In other contracted states, the parts of the device may overlap each other to reduce the radial dimensions of the device further. Such contracted states facilitate delivery of the device through a small incision or compact nesting of the device within a delivery system. The device in its expanded state is easily deformed to an elongated shape as it is removed from the eye by disengaging it from the pupil margin and pulling it out through a small incision. Alternatively, the device is removed through a small incision with or without an extraction device, in a contracted or expanded state. 
         [0031]    In one embodiment of the invention, the resilient and pliant parts of the ring are continuous. In another embodiment of the invention, the resilient and pliant parts of the ring are seamlessly merged. In other embodiments, the ring may have one or more, fused, adhesive or any other joint between the resilient and pliant parts or within a resilient or pliant part. 
         [0032]    The present invention further includes a self-expanding device to enlarge the pupil of the eye. The novelty of the device is in its slow self-expansion from a smaller size to a predetermined expanded size and shape. In its expanded state, the device comprises a ring with sides and corners, at least partially enclosing a central space and having notches and flanges. Corner portions are connectively disposed between the flanges and form receiving means for receiving a portion of the pupillary margin. The said corner portions extend into said central space. Each corner portion includes a blind end, a first limb connecting one flange to the blind end on one side, and a second limb connecting the next flange to the said blind end on an opposite side, to form a receiving means. The receiving means includes a notch sized and shaped to receive a portion of the pupillary margin such that the pupil margin and adjacent iris passes over one flange and first limb of the corner portion and under the second limb of the corner portion and the next flange. The device may have a closed or open ring configuration. The closed ring configuration has a polygonal shape. The device is either made of shape memory material, self-enlarging material or a combination of both. These self-expanding devices expand over a period of few seconds or minutes to reach their fully expanded state. The shape of the contracted smaller state of the device may or may not have resemblance to the fully expanded state of the device. The notches or flanges may not be discernible in the contracted smaller state of the device. The device when fully expanded has sufficient mechanical properties to keep the pupil expanded. The device may be made of solid or tubular filamentous material. The device may have one or more joints. The shape memory self-expanding material either spontaneously expands on being released into the eye or expands in response to a stimulus. Such stimulus could be thermal, hydrational, exposure to body fluids/physiological saline/balanced salt solution/viscoelastic material, ionic (change in pH), osmotic, chemical, electrical, magnetic, optical, electromagnetic or any other external or internal, contact or non-contact stimulus. 
         [0033]    In one embodiment, the self-expanding device expands by moving from a first shape to a second shape, by shape memory effect. The first shape is small because of folding of one or more parts of the device. The second shape is larger than the first shape because of unfolding or straightening of part or whole of the device. The circumference of the ring of the second shape is same as that of the first shape. In this embodiment, the device is partly or completely made of one or more shape memory materials. These may be shape memory alloys, shape memory polymers, or any other material exhibiting shape memory effect or a combination of such materials. Such shape memory materials are also referred to as smart materials. 
         [0034]    In another embodiment, the self-expanding device expands by moving from a first shape and size to a second shape and size, by shape memory effect as well as self-enlargement of part or whole of the device. The circumference of the ring of the second shape is larger than that of the first shape. Such a device is partly or wholly, made of shape memory hydrogels or other material capable of growth in size in response to stimuli or changes in environment. Such hydrogels are stimuli responsive, tough, low swelling and with mechanical properties which may be tuneable. These tough hydrogels may be slip-link network hydrogels, nanocomposite hydrogels, double network hydrogels, multifunctional crosslinked hydrogels, homogeneous hydrogels or hybrid ionic-covalent interpenetrating polymer network (IPN) hydrogels. These hydrogels may also be nanocomposite smart gels, DNA Hydrogels or Hybrid Hydrogels. 
         [0035]    In another embodiment, the self-expanding device is made of a self-healing and/or self-reconfiguring programmable material with mechanical properties. The device is delivered into the eye in a solid, semisolid or liquid state. The device is delivered into the eye as a closed ring or an open ring. In one form of the device, the open ring forms a closed ring inside the eye, spontaneously or in response to external or internal stimuli or when the ends are approximated. In one form, the device is delivered as multiple pieces into the eye, and these pieces either spontaneously join or are joined together inside the eye to form an open or closed ring. 
         [0036]    In one embodiment, the device is removed from the eye in its expanded size. In another embodiment, it is removed after contraction to a smaller size. In another embodiment, it is removed in smaller pieces. In another embodiment, it is removed after liquefaction or dissolving in a solvent. 
         [0037]    In another embodiment, the self-expanding device is made of a biodegradable material, which is spontaneously degraded and removed from the eye after a defined period of minutes, hours, days or months. Such a device is useful when the pupil does not dilate with medications but frequent examination of the structures deeper to the pupillary plane is desired for diagnostic or therapeutic purposes. Such a device would be helpful in children with Retinopathy of Prematurity (ROP) or adults with Diabetic Retinopathy. Such a device eliminates the effort and complications associated with removal of the device. 
         [0038]    In another embodiment, the self-expanding device is made of a biocompatible material designed as a long term prosthetic for prolonged expansion of the pupil over days, months, years or even permanently. 
         [0039]    In another embodiment, the self-expanding biodegradable or non-biodegradable device, carries and delivers drugs into the eye (i.e., is formed from a drug-eluting material). The device may be loaded with one or more drugs at initial placement and/or be topped up with one or more drugs at intervals. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0040]      FIG. 1  is an enlarged diagrammatic top perspective of the ring of the type disclosed in Malyugin U.S. Pat. No. 8,323,296, Dec. 4, 2012. 
           [0041]      FIG. 2  is an enlarged diagrammatic side view of ring of the type disclosed in Malyugin U.S. Pat. No. 8,323,296, showing iris tissue within the wedge shaped gaps of the loops. 
           [0042]      FIG. 3  is an enlarged diagrammatic top plan of the modified ring of the type disclosed in Dusek US Patent Publication 2012/0269786. 
           [0043]      FIG. 4  is a perspective view of the ring of the type disclosed in Christensen &amp; Colvard US Patent Publication 2013/0096386. 
           [0044]      FIG. 5  is an enlarged diagrammatic top view of one form of the device of the present invention, showing a square shaped continuous ring with a joint. 
           [0045]      FIG. 6  is an illustration of the pupil maintained in an enlarged position by the device of  FIG. 5 . 
           [0046]      FIG. 7  is an enlarged diagrammatic side view showing the relation of iris tissue to the notches. 
           [0047]      FIG. 8  is an illustration of the insertion of the ring device into the eye and engagement of the pupillary margin with the first notch of the device of  FIG. 5 . 
           [0048]      FIG. 9  is an illustration of the stretched pupillary margin after engagement by the second notch of the device of  FIG. 5 . 
           [0049]      FIG. 10  is an illustration of the pupil fully enlarged after engagement by all four notches of the device of  FIG. 5 . 
           [0050]      FIG. 11  is an enlarged diagrammatic top view of one form of the device of the present invention, showing a discontinuous ring with five sides, four corners and six notches. 
           [0051]      FIG. 12  is an illustration of the pupil maintained in an enlarged position by the device of  FIG. 11 . 
           [0052]      FIG. 13  is an enlarged diagrammatic top perspective of one form of the device of the present invention, showing alternate flanges of the device of  FIG. 11 , gently tilted backwards. 
           [0053]      FIG. 14  is an enlarged diagrammatic top view of one form of the device of the present invention, showing plurality of positioning holes on a hexagon shaped continuous ring with no joint. 
           [0054]      FIG. 15  is an enlarged diagrammatic top view of one form of the device of the present invention, showing engagement of the pupillary margin by notches formed by an inward loop of the strand between two outward digit shaped protruding loops of the strand of a square shaped continuous ring with no joint. 
           [0055]      FIG. 16  is an enlarged diagrammatic top view of one form of the device of the present invention, showing engagement of the pupillary margin by two adjacent notches at the corners of a square shaped continuous ring with no joint. 
           [0056]      FIG. 17  is an enlarged diagrammatic top view of another form of the device of the present invention made of four solid single strand units, showing a square shaped continuous ring in its contracted state with four pupil-engaging parts or notches and four expandable supporting parts with interlocking sliding joints. 
           [0057]      FIG. 18  is an enlarged diagrammatic top view of the device of  FIG. 17  showing the square shaped continuous ring in its expanded state. 
           [0058]      FIG. 19  is a diagrammatic view showing a unit of the device of  FIG. 17  and its cross sections at different parts. 
           [0059]      FIG. 20  is a diagrammatic view of a step in forming the interlocking sliding joint of the device of  FIG. 17  showing the first end of a unit being threaded through the hole of the second end of the preceding unit. 
           [0060]      FIG. 21  is a diagrammatic view of another step in forming the interlocking sliding joint of the device of  FIG. 17  showing first end of a unit being threaded through the hole of the second end of the preceding unit and first end of the preceding unit being threaded through the hole of the first end of the consecutive unit. 
           [0061]      FIG. 22  is a diagrammatic view of the final step in forming the interlocking sliding joint of the device of  FIG. 17  showing two consecutive units of the device of  FIG. 17  interconnected at an interlocking sliding joint at the supporting part. 
           [0062]      FIG. 23  is an enlarged diagrammatic top view of the telescopic sliding joint at the supporting part of one form of the device of the present invention made of a tubular strand with square cross section. 
           [0063]      FIG. 24  is a diagrammatic longitudinal section through the telescopic interlocking sliding joint of the device of  FIG. 23  showing an inward flange of the outer tube and an outward flange of the inner tube. 
           [0064]      FIG. 25  is a top view of the device of  FIG. 17 , in use in a non-dilated pupil of the eye. 
           [0065]      FIG. 26  is a top view of the device of  FIG. 17 , in an expanded state in an enlarged, or dilated, pupil. 
           [0066]      FIG. 27  is an enlarged diagrammatic top perspective of a square closed ring of the present invention in its expanded undeformed state with shape memory resilient notches and shape retaining pliant flanges. 
           [0067]      FIG. 28  is an enlarged diagrammatic top perspective of a hexagonal closed ring of the present invention in its expanded undeformed state with shape memory resilient notches and shape retaining pliant flanges. 
           [0068]      FIG. 29  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , with all four notches and all four flanges deformed. 
           [0069]      FIG. 30  is an enlarged diagrammatic top perspective view of a contracted state of the device of  FIG. 27 , compactly nested in a delivery device, with all four notches and all four flanges deformed. 
           [0070]      FIG. 31  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , after expulsion from the delivery device of  FIG. 30 , with all four notches undeformed and all four flanges still deformed. 
           [0071]      FIG. 32  is an enlarged diagrammatic top view of the device of  FIG. 27 , being enlarged manually from the contracted state of  FIG. 31 , with two Kuglen hooks. 
           [0072]      FIG. 33  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , with all four notches and only two flanges deformed. 
           [0073]      FIG. 34  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , after expulsion from a delivery device, after having been in a contracted state of  FIG. 33 , with all four notches undeformed and two flanges deformed. 
           [0074]      FIG. 35  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , with two Kuglen hooks, causing deformation of the two previously undeformed flanges of  FIG. 34 , to enable the notches, receive the non-dilating pupil margin. 
           [0075]      FIG. 36  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , with deformation of two flanges as in  FIG. 35 , and use of Kuglen hooks to straighten the loops of the other two flanges, to expand the device and cause expansion of the pupil. 
           [0076]      FIG. 37  is an enlarged diagrammatic top perspective of one embodiment of the expanded state of a self-expanding square closed ring of the present invention made of shape memory material. 
           [0077]      FIG. 38  is an enlarged diagrammatic top perspective of one embodiment of the expanded state of a self-expanding hexagonal closed ring of the present invention made of shape memory material. 
           [0078]      FIG. 39  is an enlarged diagrammatic top view of the device of  FIG. 37  showing the contracted state. 
           [0079]      FIG. 40  is an enlarged diagrammatic top perspective view of the device of  FIG. 39 , compactly nested in a delivery device. 
           [0080]      FIG. 41  is an enlarged diagrammatic top view of the device of  FIG. 37 , in a partially self-expanded state. 
           [0081]      FIG. 42  is an enlarged diagrammatic top view of another embodiment of the contracted state of the device of  FIG. 37 . 
           [0082]      FIG. 43  is an enlarged diagrammatic top view of the device of  FIG. 42 , compactly nested within a tubular sleeve. 
           [0083]      FIG. 44  is an enlarged diagrammatic top view of the device of  FIG. 42 , in nearly fully self-expanded state. 
           [0084]      FIG. 45  is an enlarged diagrammatic top view of a contracted state of a device of the present invention made of shape memory self-enlarging material. 
           [0085]      FIG. 46  is an enlarged diagrammatic top view of the fully expanded state of the device of  FIG. 45 . 
           [0086]      FIG. 47  is an enlarged diagrammatic top view of a contracted and open ring state of a device of the present invention made of self-enlarging, self-healing and self-reconfiguring programmable material. 
           [0087]      FIG. 48  is an enlarged diagrammatic top view of a fully expanded and closed ring state of a device of the present invention formed by self-enlargement, self-healing and self-reconfiguration of the device of  FIG. 47 . 
           [0088]      FIG. 49  is an enlarged perspective view of an alternative embodiment of the invention. 
           [0089]      FIG. 50  is an enlarged perspective view of another alternative embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0090]    The relevant features of existing devices and the novelty of the present invention, is illustrated in the accompanying drawings, throughout which, like reference numerals indicate corresponding parts in the various figures. 
         [0091]      FIG. 5  shows an enlarged diagrammatic top view of the ring of the present invention used for enlargement and prevention of collapse of the pupil. The ring  47  is made of any resiliently flexible strand, for example, thermally treated 4-0 nylon suture. It is a continuous ring, has a square configuration and has four sides  48 ,  49 ,  50  and  51 , joined by corner portions. Side  50  has ends  52  and  53  joined at the butt joint  54  with adhesive. Each one of the corner portions  55 ,  56 ,  57  and  58 , forms a notch, same numerals representing the notches. Corner portion  56  joins side  49  to side  50 , which are perpendicular to each other. At the corner portion  56 , the strand loops inwards to form a notch. Three distinct bends of the strand in the same plane form the notch. A first acute bend  59 , second rounded return bend  60 , and a third acute bend  61 . The notch has a narrow outward opening  62 , which allows iris tissue to enter the notch. Inwards, the notch has a blind, bulbous receptacle  63 , which engages the pupillary margin and iris tissue gently. Corner portions  55 ,  57  and  58  are identical to corner portion  56 . Parts  64  and  65  of corner portions  57  and  58  respectively, along with side  51 , form an outward flange. Sides  48 ,  49  and  50 , form similar flanges. The ring comprises alternate notches and flanges, all being in the same plane and enclosing a space  66 . 
         [0092]      FIG. 6  shows an illustration of the pupil maintained in an enlarged position by the ring  47  of  FIG. 5 . The notches at corners  55 ,  56 ,  57  and  58 , engage the pupillary margin  67  at different parts and push them apart, causing enlargement of the pupil. The flanges at sides  48  and  50  remain in front of the Iris  68 . The flanges at sides  49  and  51  remain behind the Iris and are not visible. The alternate notches and flanges cause bending of the pupillary margin and iris tissue somewhat like a paper clip. This results in a secure yet reversible engagement. The central opening  66 , allows wide view of the structures deeper to the pupillary plane. 
         [0093]      FIG. 7  shows an enlarged diagrammatic side view of the relation of iris tissue to the notches. This side view is at a vertical plane passing through the middle of any two adjacent notches of  FIG. 6 . The device distinctly bends the iris tissue  68 , four times, as it passes through the two notches. From the left as viewed in  FIG. 7 , the iris  68  passes above the side element  69  and outer limb  70  of the notch  71 . The first bend is at an obtuse angle as it passes downwards around the outer limb  70  of the notch  71  and through the notch. The second bend is at an obtuse angle to pass under the inner limb  72  of the notch  71 . Iris  68  then makes a third bend at an obtuse angle as it passes upwards around the inner limb  73  of the notch  74  and through the notch. The final fourth bend is at an obtuse angle to pass above the outer limb  75  of the notch  74  and side element  76 . As viewed in  FIG. 7 , side element  69 , outer limb  70  of the notch  71 , the notch  71 , inner limb  72  of the notch  71 , inner limb  73  of the notch  74 , the notch  74 , outer limb  75  of the notch  74  and side element  76 , all lie in the same plane. 
         [0094]      FIG. 8  refers to the usage of the invention, is an illustration of the insertion of the ring  47  of  FIG. 5 , into the eye and engagement of the pupillary margin  67  with the first notch  55  of the ring. A forceps (not shown here) carries the device or an injector (not shown here) delivers the device through the incision  77 , into the anterior chamber of the eye. The flexible square ring  47  adopts a rhomboid configuration as it negotiates through a much smaller incision  77 . The notches  56  and  58  open up and temporarily straighten out as the device passes through the incision. The leading first notch  55  hooks and engages the pupillary margin  67  pushing it in an outward direction. The pupillary margin  67  is lifted with a Hirschman hook (not shown here) to tuck the flange  49  under the pupillary margin  67  and iris  68 . 
         [0095]      FIG. 9  refers to the usage of the invention in further detail, is an illustration of the stretched pupillary margin after engagement by the second notch  56  of the device  47  of  FIG. 5 . The resiliently flexible ring  47  has now returned to its square configuration. Notches  55  and  56  have engaged the pupillary margin  67  at two different points and pushed them apart. Flange  49  (not visible here), remains tucked under the pupillary margin  67 , while flanges  48 ,  50  and  51 , remain in front of the iris  68 . As the pupillary margin is hooked again with an iris or hirschman hook, introduced through a side port (not shown here), a forceps introduced through another side port (not shown here), holds the flange  51  and tucks it under the pupillary margin  67  and iris  68 . 
         [0096]      FIG. 10  refers to the usage of the invention in further detail, is an illustration of the pupillary margin  67 , fully enlarged and adopting a square configuration after engagement by all four notches  55 ,  56 ,  57  and  58  of the device  47  of  FIG. 5 . The flanges  48  and  50  remain in front of the Iris  68 . The flanges at sides  49  and  51  remain behind the iris and are not visible. The central opening  66 , allows wide view of the structures deeper to the pupillary plane. On completion of surgery, the device is easily disengaged from the pupillary margin and pulled out with a forceps. The device exits the eye without snagging the incision because notches are in the same plane as the flanges and are capable of straightening temporarily. 
         [0097]      FIG. 11  is an enlarged diagrammatic top view of another form of the device of the present invention, showing a discontinuous ring  78  with ends  79  and  80 , which are blunt or olive shaped to prevent damage to delicate structures of the eye. The discontinuous ring  78  has five sides  81 ,  82 ,  83 ,  84  and  85 , which are shaped like flanges. Corner portions joining these sides are internally obtuse angled. The four corner portions  87 ,  88 ,  89  and  90 , form four notches, same numerals representing the notches. Notch  86  is at the first end and notch  91  is at the second end of the ring. In the device of  FIG. 11 , the angles at corner  87  and  90  are equal to each other and the angles at corner  89  and  90  are equal to each other. The first side  81  and the fifth side  85  are parallel to each other, giving the device a flat top house shape. The central space  92 , is closed on five sides by the device, and open on one side. In another form of the device of  FIG. 11  (not shown here), the first side  81  and the fifth side  85 , are unparallel, such that the distance between the ends  79  and  80 , is more than that between the first corner  87  and fourth corner  90 , giving the device the shape of a flat top tower. 
         [0098]      FIG. 12  is an illustration of the pupil maintained in an enlarged position by the device of  FIG. 11 . The notches  86 ,  87 ,  88 ,  89 ,  90  and  91 , engage the pupillary margin  67  at different parts and push them apart, causing enlargement of the pupil. Ends  79  and  80 , and flanges  82  and  84  remain in front of the Iris  68 . The flanges  81 ,  83  and  85  remain behind the Iris and are not visible. The constricting force of the pupil draws the notches at the ends  79  and  80  of the discontinuous ring closer and the resultant shape of the central space  92  of the device and that of the pupil is a hexagon. The central space  92 , allows wide view of the structures deeper to the pupillary plane. While the device of  FIG. 11  may be inserted into the eye, in the manner described above for the device of  FIG. 5 , the device may alternatively be inserted end first, into the eye, through a much smaller side port incision. The entire device is inserted into the anterior chamber and placed on the iris. The pupillary margin is hooked with an iris or hirschman hook, introduced through one side port incision, while a forceps introduced through another side port, holds flange  83  and tucks it under the pupillary margin  67 . Similarly, flanges  81  and  85  are tucked under the pupillary margin. 
         [0099]      FIG. 13  is an enlarged diagrammatic top perspective of one form of the device of the present invention, showing alternate flanges of the device of  FIG. 11 , gently tilted backwards. Device  93  allows easier tucking of the flanges under the pupillary margin. Flanges  81 ,  83  and  85 , shown in dotted lines, represent the previous straight position of flanges. Flanges  94 ,  95  and  96  represent the backward tilted flanges, respectively. The flanges are tilted all the way up to the centre of the notch or only at the peripheral edge. The position of flanges  82  and  84 , which remain in front of the pupillary margin, is unaltered. Although tilted flanges are shown on the device of the present invention of  FIG. 11 , it is understood that such flanges may be present on all the forms of the device. 
         [0100]      FIG. 14  is an enlarged diagrammatic top view of one form of the device of the present invention, showing plurality of positioning holes on a hexagon shaped continuous ring with no joint. Holes  98  and  99  are shown on a flange and notch respectively on the device  97 . These holes are partial thickness or full thickness. These holes allow easy manipulation of the device inside the eye with the help of a pointed instrument called dialler. Although positioning holes or eyelets are shown on the device of the present invention of  FIG. 14 , it is understood that such positioning holes or eyelets may be present on all the forms of the device. 
         [0101]      FIG. 15  is an enlarged diagrammatic top view of one form of the device of the present invention, showing engagement of the pupillary margin  67  by notches formed by an inward loop of the strand between two outward digit shaped protruding loops of the strand of a square shaped continuous ring with no joint. The ring  100  has four side elements  101 ,  102 ,  103  and  104 . Corner portions  105 ,  106 ,  107  and  108 , join the side elements. Corner portion  108  joins side  101  to side  104 , which are perpendicular to each other. At the corner portion  108 , the strand makes three distinct loops in the same plane to form a notch. Loops  115  and  116  are outward digit like protrusions. Notch  117 , is formed by an inward loop between these two outward looped protrusions. Corner portions  105 ,  106  and  107  are identical to corner portion  108  and form notches  118 ,  119  and  120  respectively. The pupillary margin  67  has a square configuration as it is engaged by the notches  117 ,  118 ,  119  and  120 , as it passes behind the elements  110 ,  111 ,  114  and  115 , and in front of elements  112 ,  113 ,  116  and  109 . The enclosed space  121 , allows wide view of the structures deeper to the pupillary plane. 
         [0102]      FIG. 16  is an enlarged diagrammatic top view of one form of the device of the present invention, showing engagement of the pupillary margin  67  by two adjacent notches at the corners of a square shaped continuous ring with no joint. The ring  122  has four side elements  123 ,  124 ,  125  and  126 . Corner portions  127 ,  128 ,  129  and  130 , join the side elements. Corner portion  127  joins side  123  to side  124 , which are perpendicular to each other. At the corner portion  127 , the strand makes three distinct loops in the same plane to form two adjacent paired notches or a double notch. Paired notches  131  and  132  are formed by two loops directed inwards. A digit like structure  139 , is formed between these two notches by a loop directed outwards. Corner portions  128 ,  129  and  130 , are identical to corner portion  127  and form paired notches  133 ,  134  and  135 ,  136  and  137 ,  138  respectively. The pupillary margin  67  has a square configuration, engaged by the notches  131 ,  132 ,  133 ,  134 ,  135 ,  136 ,  137  and  138 . The pupillary margin  67  passes behind side elements  123 ,  124 ,  125  and  126 , and in front of elements  139 ,  140 ,  141  and  142 . The enclosed space  143 , allows wide view of the structures deeper to the pupillary plane. The pupillary margin  67  could alternately pass (not shown here) in front of side elements  123 ,  124 ,  125  and  126 , and behind elements  139 ,  140 ,  141  and  142 . 
         [0103]      FIG. 17  shows an enlarged diagrammatic top view of one form of the device of the present invention in its contracted state. The device  31 ′ is a square shaped continuous ring entirely disposed in a single plane made of resiliently flexible material comprising four solid single strand units  32 ′,  33 ′,  34 ′ and  35 ′. The device has four pupil-engaging notches (loops)  36 ′,  37 ′,  38 ′ and  39 ′ and four expandable supporting parts  40 ′,  41 ′,  42 ′ and  43 ′ with interlocking sliding joints  44 ′,  45 ′,  46 ′ and  47 ′. At the interlocking sliding joint  46 ′ the second end  48 ′ of unit  33 ′ passes through the hole  49 ′ in the first end  50 ′ of unit  34 ′ and the first end  50 ′ of unit  34 ′ passes through the hole  51 ′ in the second end  48 ′ of unit  33 ′. The device  31 ′ encloses a space  52 ′. 
         [0104]      FIG. 18  is an enlarged diagrammatic top view of the device  31 ′ of  FIG. 17  showing the square shaped continuous ring in its expanded state. Supporting parts  40 ′,  41 ′,  42 ′ and  43 ′ have expanded because of sliding between the second end of the preceding unit and the first end of the consecutive unit at the interlocking joints  44 ′,  45 ′,  46 ′ and  47 ′. Because of expansion of the supporting parts, there is an increase in the circumference of the device, increase in the radial dimension of the device and increase in the size of the enclosed space  52 ′. The interlocking arrangement at the joints limits the expansion of the supporting parts and hence limits the size of the expanded state of the device. 
         [0105]      FIG. 19  is a diagrammatic view of unit  32 ′ of the device  31 ′ of  FIG. 17 . The unit has a first end  53 ′ with a hole  54 ′, the pupil engaging notch  36 ′ and the second end  55 ′ with a hole  56 ′. After completion of the notch  36 ′, the strand gradually flattens into a broader and thinner leaf. The cross sections at planes  57 ′,  58 ′ and  59 ′ are round  60 ′, ellipse  61 ′ and narrow rectangle  62 ′ respectively. 
         [0106]      FIG. 20  is a diagrammatic view of the first step in forming the interlocking sliding joint of the device of  FIG. 17 , showing two consecutive units  32 ′ and  33 ′ of the device  31 ′. The first end  63 ′ of unit  33 ′ is threaded through the hole  56 ′ of the second end  55 ′ of the preceding unit  32 ′. 
         [0107]      FIG. 21  is a diagrammatic view of the next step in forming the interlocking sliding joint of the device of  FIG. 4  showing two consecutive units  32 ′ and  33 ′ of the device  31 ′. As shown in  FIG. 20  the first end  63 ′ of unit  33 ′ is threaded through the hole  56 ′ of the second end  55 ′ of the preceding unit  32 ′. Then the first end  53 ′ of unit  32 ′ is bent towards its second end  55 ′ and threaded through the hole  64 ′ of the first end  63 ′ of the consecutive unit  33 ′. 
         [0108]      FIG. 22  is a diagrammatic view of the final step in forming the interlocking sliding joint of the device of  FIG. 17  showing consecutive units  32 ′ and  33 ′ of the device  31 ′. The interlocking sliding joint  45 ′ at the supporting part  40 ′ connects the second end  55 ′ of unit  32 ′ to the first end  63 ′ of unit  32 ′. The supporting part  40 ′ expands as units  32 ′ and  33 ′ are drawn apart bringing the ends  55 ′ and  63 ′ close together. 
         [0109]      FIG. 23  is an enlarged diagrammatic view of a telescopic slip joint of one form of the device of the present invention. The inner tube  65 ′ telescopes into the outer tube  66 ′ at joint  67 ′. The inner tube  65 ′ has a square cross section  68 ′ with area less than that of the outer tube  66 ′, which also has a square cross section. The square cross section prevents axial rotation of the tubes. 
         [0110]      FIG. 24  is a diagrammatic longitudinal section through the telescopic interlocking slip joint of the device of  FIG. 23 . The outer tube  66 ′ has an inward flange  69 ′ and the inner tube  65 ′ has an outward flange  70 ′, which restricts the limit of expansion of the supporting part. 
         [0111]      FIG. 25  refers to the usage of the invention, is an illustration of the placement of the device  31 ′ of  FIG. 17 , within the non-dilated pupil  71 ′ of the eye. A forceps (not shown here) carries the device or an injector (not shown here) delivers the device through an incision in the cornea into the anterior chamber of the eye. The flexible square ring is held with a forceps and the notches are engaged to the pupil margin  72 ′. 
         [0112]      FIG. 26  is an illustration of usage of the invention in further detail, and shows the device  31 ′ in an expanded state and engaged to the pupil margin, resulting in an expanded pupil. The device  31 ′ is engaged to the pupil margin  72 ′ by notches  36 ′,  37 ′,  38 ′ and 39′. Supporting parts  40 ′ and  42 ′ are pushed apart using two Kuglen hooks (not shown here) to expand supporting parts  41 ′ and  43 ′. Supporting parts  40 ′ and  42 ′ are tucked under the pupil margin  72 ′. Supporting parts  41 ′ and  43 ′, lying anterior to the pupil margin are also pushed apart to expand the supporting parts  40 ′ and  42 ′. Expansion of the enclosed space  52 ′ results in expansion of the pupil  71 ′. The pupil is expanded to the desired size. Supporting parts  40 ′ and  42 ′ are tucked under the pupil margin  72 ′ and iris  73 ′ and are not visible. Supporting parts  41 ′ and  43 ′ and joints  44 ′ and  46 ′ lying anterior to the iris  73 ′ are visible. 
         [0113]      FIG. 27  is an enlarged diagrammatic top perspective of a square closed ring  23 ″ of the present invention, in its expanded undeformed state showing shape memory resilient notches  24 ″,  25 ″,  26 ″ and  27 ″ and shape retaining pliant flanges  28 ″,  29 ″,  30 ″ and  31 ″. Flange  28 ″ has a first end  32 ″ and a second end  33 ″. Flange  29 ″ has a first end  34 ″ and a second end  35 ″. Notch  24 ″ has a first limb  36 ″, which connects the second end  33 ″ of flange  28 ″ to the blind end  37 ″ of the notch. Second limb  38 ″ of notch  24 ″ connects the blind end  37 ″ to the first end  34 ″ of flange  29 ″. Limb  39 ″ of notch  25 ″, connects second end  35 ″ of flange  29 ″ to blind end  40 ″. Limb  41 ″ connects blind end  40 ″ of notch  25 ″ to first end  42 ″ of flange  30 ″. Limb  43 ″ of notch  26 ″, connects second end  44 ″ of flange  30 ″ to blind end  45 ″. Limb  46 ″ connects blind end  45 ″ of notch  26 ″ to first end  47 ″ of flange  31 ″. Limb  48 ″ of notch  27 ″, connects second end  49 ″ of flange  31 ″ to blind end  50 ″. Limb  51 ″ connects blind end  50 ″ of notch  27 ″ to first end  32 ″ of flange  28 ″. In the enlarged and undeformed state, the ring  23 ″ encloses a space  52 ″. Notches  24 ″,  25 ″,  26 ″ and  27 ″ receive and engage different parts of the pupil margin. In one method of engagement, the pupil margin and adjacent iris pass over limb  51 ″, flange  28 ″, limb  36 ″, limb  41 ″, flange  30 ″ and limb  43 ″ and under limb  38 ″, flange  29 ″, limb  39 ″, limb  46 ″, flange  31 ″ and limb  48 ″. In an alternate method of engagement, the pupil margin and adjacent iris pass under limb  51 ″, flange  28 ″, limb  36 ″, limb  41 ″, flange  30 ″ and limb  43 ″ and over limb  38 ″, flange  29 ″, limb  39 ″, limb  46 ″, flange  31 ″ and limb  48 ″. The enclosed square space, with blind ends  37 ″,  40 ″,  45 ″ and  50 ″ as the corners, represents the expanded pupil and provides visualization and access to structures lying deeper to this plane. 
         [0114]      FIG. 28  is an enlarged diagrammatic top perspective of a hexagonal closed ring  53 ″ of the present invention, in its expanded undeformed state showing shape memory resilient notches  54 ″,  55 ″,  56 ″,  57 ″,  58 ″ and  59 ″ and shape retaining pliant flanges  60 ″,  61 ″,  62 ″,  63 ″,  64 ″ and  65 ″ and enclosing a space  66 ″. Notches  54 ″,  55 ″,  56 ″,  57 ″,  58 ″ and  59 ″ receive and engage different parts of the pupil margin. In one method of engagement, the pupil margin and adjacent iris pass over flanges  60 ″,  62 ″, and  64 ″ and under flanges  61 ″,  63 ″ and  65 ″. In an alternate method of engagement, the pupil margin and adjacent iris pass under flanges  60 ″,  62 ″, and  64 ″ and over flanges  61 ″,  63 ″ and  65 ″. Blind ends  66 ″,  67 ″,  68 ″,  69 ″,  70 ″ and  71 ″ of notches form the six corners of an enclosed hexagonal space, which represents the expanded pupil and provides visualization and access to structures lying deeper to this plane. 
         [0115]      FIG. 29  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , showing all four notches  24 ″,  25 ″,  26 ″, and  27 ″ and all four flanges  28 ″,  29 ″,  30 ″ and  31 ″, in a deformed state. Limbs  36 ″ and  38 ″ of notch  24 ″ are approximated to each other and the notch is narrowed. Similarly, notches  25 ″,  26 ″ and  27 ″ are narrowed. Flange  28 ″ is folded to form loop  72 ″. Flange  29 ″ is folded to form loop  73 ″. Flange  30 ″ is folded over itself to form loop  74 ″. Flange  31 ″ is folded over itself to form loop  75 ″. Such folding of the notches and flanges results in obliteration of the enclosed space  52 ″. 
         [0116]      FIG. 30  is an enlarged diagrammatic top perspective view of a contracted state of the device  23 ″ of  FIG. 27 , showing it compactly nested in a delivery device  76 ″, with all four notches  24 ″,  25 ″,  26 ″, and  27 ″ and all four flanges  28 ″,  29 ″,  30 ″ and  31 ″ deformed. The delivery device  76 ″ comprises an outer tube  77 ″ and a plunger  78 ″. Outer tube  77 ″ carries the device  23 ″ through a corneal incision into the eye. Forward motion of the plunger  78 ″ expels the device  23 ″ into the anterior chamber of the eye. 
         [0117]      FIG. 31  is an enlarged diagrammatic top view of a contracted state of the device  23 ″ of  FIG. 27 , after expulsion from the delivery device into the eye, showing all four notches  24 ″,  25 ″,  26 ″, and  27 ″ undeformed and all four flanges  28 ″,  29 ″,  30 ″ and  31 ″ still deformed. The resilient limbs  36 ″ and  38 ″ of notch  24 ″, having shape memory, have moved apart and the notch has returned to its undeformed shape. Similarly, notches  25 ″,  26 ″, and  27 ″ have also returned to their undeformed states. The pliant flanges  28 ″,  29 ″,  30 ″ and  31 ″ being shape retaining, remain deformed. This contracted state of the device allows the notches to engage the margin of the non-dilating pupil without any stretching. 
         [0118]      FIG. 32  is an enlarged diagrammatic top view of the device of  FIG. 27 , showing the contracted ring  23 ″, being enlarged manually using two Kuglen hooks  79 ″ and  80 ″. One Kuglen hook  79 ″ engages the first end  47 ″ of flange  31 ″, and a second Kuglen hook  80 ″ engages the second end  49 ″ of flange  31 ″. As the two Kuglen hooks are moved apart, the loop  75 ″ of shape retaining pliant flange  31 ″ gradually straightens in a very controlled manner. Similarly, loops  72 ″,  73 ″ and  74 ″, are straightened one by one to produce controlled expansion of the device and enlargement of the enclosed space  52 ″ and expansion of the pupil. As the device is expanded, the pupil margin and adjacent iris passes either over or under opposite flanges. 
         [0119]      FIG. 33  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , showing all four notches  24 ″,  25 ″,  26 ″, and  27 ″ and only two flanges  29 ″ and  31 ″ deformed. Limbs  36 ″ and  38 ″ of notch  24 ″ are approximated to each other and the notch is narrowed. Similarly, notches  25 ″,  26 ″ and  27 ″ are narrowed. Flange  29 ″ is folded to form loop  81 ″ and flange  31 ″ is folded to form loop  82 ″. Flanges  28 ″ and  30 ″ remain undeformed. This results in contraction of the device breadth wise to facilitate easy insertion through a small incision. This contracted state also facilitates compact nesting within a delivery device. 
         [0120]      FIG. 34  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , after expulsion from a delivery device, after having been in a contracted state of  FIG. 33 , showing all four notches  24 ″,  25 ″,  26 ″, and  27 ″ undeformed and two flanges  29 ″ and  31 ″ still deformed. The device is merely placed in the anterior chamber of the eye and the notches do not receive the pupil margin at this stage. 
         [0121]      FIG. 35  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , showing deformation of the two previously undeformed flanges  28 ″ and  30 ″ of  FIG. 34 . Kuglen hooks  83 ″ and  84 ″ engage notches  24 ″ and  27 ″ respectively and draw them towards each other causing flange  28 ″ to be deformed. Kuglen hooks  85 ″ and  86 ″ engage notches  25 ″ and  26 ″ respectively and draw them towards each other causing flange  30 ″ to be deformed. This brings the four notches  24 ″,  25 ″,  26 ″, and  27 ″ close to each other and enables the notches receive the non dilating pupil margin without any stretching. As flanges  28 ″ and  30 ″ are deformed they remain over the iris. 
         [0122]      FIG. 36  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 27 , showing deformation of flanges  28 ″ and  30 ″ as in  FIG. 35 . Notches  24 ″,  25 ″,  26 ″, and  27 ″ receive the pupil margin in a manner that the pupil margin and adjacent iris pass under flanges  28 ″ and  30 ″, over first end  34 ″ and second end  35 ″ of flange  29 ″, and over first end  47 ″ and second end  49 ″ of flange  31 ″. Kuglen hook  83 ″ now engages the first end  34 ″ of flange  29 ″ and Kuglen hook  85 ″ now engages the second end  35 ″ of flange  29 ″ to straighten the loop  81 ″ of flange  29 ″. Similarly, Kuglen hook  86 ″ now engages the first end  47 ″ of flange  31 ″ and Kuglen hook  84 ″ now engages the second end  49 ″ of flange  31 ″ to straighten the loop  82 ″ of flange  31 ″. The loops  81 ″ and  82 ″ are straightened in a manner that the pupil margin and adjacent iris pass over the straightened flanges  29 ″ and  31 ″ and under the straightened flanges  28 ″ and  30 ″. This causes expansion of the device and in effect expansion of the pupil. 
         [0123]      FIG. 37  is an enlarged diagrammatic top perspective of a square closed ring  23 ′″ of the present invention made of shape memory material, in its expanded state showing notches  24 ′″,  25 ′″,  26 ′″ and  27 ′″ and flanges  28 ′″,  30 ′″ and  31 ′″. Flange  28 ′″ has a first end  32 ′″ and a second end  33 ′″. Flange  29 ′″ has a first end  34 ′″ and a second end  35 ′″. Notch  24 ′″ has a first limb  36 ′″, which connects the second end  33 ′″ of flange  28 ′″ to the blind end  37 ′″ of the notch. Second limb  38 ′″ of notch  24 ′″ connects the blind end  37 ′″ to the first end  34 ′″ of flange  29 ′″. Limb  39 ′″ of notch  25 ′″, connects second end  35 ′″ of flange  29 ′″ to blind end  40 ′″. Limb  41 ′″ connects blind end  40 ′″ of notch  25 ′″ to first end  42 ′″ of flange  30 ′″. Limb  43 ′″ of notch  26 ′″, connects second end  44 ′″ of flange  30 ′″ to blind end  45 ′″. Limb  46 ′″ connects blind end  45 ′″ of notch  26 ′″ to first end  47 ′″ of flange  31 ′″. Limb  48 ′″ of notch  27 ′″, connects second end  49 ′″ of flange  31 ′″ to blind end  50 ′″. Limb  51 ′″ connects blind end  50 ′″ of notch  27 ′″ to first end  32 ′″ of flange  28 ′″. In the enlarged and undeformed state, the ring  23 ′″ encloses a space  52 ′″. Notches  24 ′″,  25 ′″,  26 ′″ and  27 ′″ receive and engage different parts of the pupil margin. In one method of engagement, the pupil margin and adjacent iris pass over limb  51 ′″, flange  28 ′″, limb  36 ′″, limb  41 ′″, flange  30 ′″ and limb  43 ′″ and under limb  38 ′″, flange  29 ′″, limb  39 ′″, limb  46 ′″, flange  31 ′″ and limb  48 ′″. In an alternate method of engagement, the pupil margin and adjacent iris pass under limb  51 ′″, flange  28 ′″, limb  36 ′″, limb  41 ′″, flange  30 ′″ and limb  43 ′″ and over limb  38 ′″, flange  29 ′″, limb  39 ′″, limb  46 ′″, flange  31 ′″ and limb  48 ′″. The enclosed square space, with blind ends  37 ′″,  45 ′″ and  50 ′″ as the corners, represents the expanded pupil and provides visualization and access to structures lying deeper to this plane. 
         [0124]      FIG. 38  is an enlarged diagrammatic top perspective of a hexagonal closed ring  53 ′″ of the present invention made of shape memory material, in its expanded state, showing notches  54 ′″,  55 ′″,  56 ′″,  57 ′″,  58 ′″ and  59 ′″ and flanges  60 ′″,  61 ′″,  62 ′″,  63 ′″,  64 ′″ and  65 ′″ and enclosing a space  66 ′″. Notches  54 ′″,  55 ′″,  56 ′″,  57 ′″,  58 ′″ and  59 ′″ receive and engage different parts of the pupil margin. In one method of engagement, the pupil margin and adjacent iris pass over flanges  60 ′″,  62 ′″, and  64 ′″ and under flanges  61 ′″,  63 ′″ and  65 ′″. In an alternate method of engagement, the pupil margin and adjacent iris pass under flanges  60 ′″,  62 ′″, and  64 ′″ and over flanges  61 ′″,  63 ′″ and  65 ′″. Blind ends  66 ′″,  67 ′″,  68 ′″,  69 ′″,  70 ′″ and  71 ′″ of notches form the six corners of an enclosed hexagonal space, which represents the expanded pupil and provides visualization and access to structures lying deeper to this plane. 
         [0125]      FIG. 39  is an enlarged diagrammatic top view of a contracted state of the device of  FIG. 37 , showing all four notches  24 ′″,  25 ′″,  26 ″, and  27 ′″ and all four flanges  28 ′″,  29 ′″,  30 ′″ and  31 ′″, in a deformed state. Limbs  36 ′″ and  38 ′″ of notch  24 ′″ are approximated to each other and the notch is narrowed. Similarly, notches  25 ′″,  26 ′″ and  27 ′″ are narrowed. Flange  28 ′″ is folded to form loop  72 ′″. Flange  29 ′″ is folded to form loop  73 ′″. Flange  30 ′″ is folded over itself to form loop  74 ′″. Flange  31 ′″ is folded over itself to form loop  75 ′″. Such folding of the notches and flanges results in obliteration of the enclosed space  52 ′″. 
         [0126]      FIG. 40  is an enlarged diagrammatic top perspective view of a contracted state of the device  23 ′″ of  FIG. 39 , showing it compactly nested in a delivery device  76 ′″, with all four notches  24 ′″,  25 ′″,  26 ′″, and  27 ′″ and all four flanges  28 ′″,  29 ′″,  30 ′″ and  31 ′″ deformed. The delivery device  76 ′″ comprises an outer tube  77 ′″ and a plunger  78 ′″. Outer tube  77 ′″ carries the device  23 ′″ through a corneal incision into the eye. Forward motion of the plunger  78 ′″ expels the device  23 ′″ into the anterior chamber of the eye. 
         [0127]      FIG. 41  is an enlarged diagrammatic top view of a partially expanded state of the device  23 ′″ of  FIG. 39 , after expulsion from the delivery device into the eye, showing all four notches  24 ′″,  25 ′″,  26 ′″, and  27 ′″ and all four flanges  28 ′″,  29 ′″,  30 ′″ and  31 ′″ having partially regained their shape due to shape memory. This partially expanded state of the device allows the notches to be engaged to the margin of the non-dilating pupil without any stretching. The device self-expands by moving from the shape of  FIG. 39  to the shape of  FIG. 37  due to shape memory. 
         [0128]      FIG. 42  is an enlarged diagrammatic top view of another embodiment of the contracted state of the device of  FIG. 37 , showing the notches and flanges of ring  23 ′″ folded to result in shape that is smaller in size. Notches  24 ′″,  25 ′″,  26 ′″ and  27 ′″ are narrowed and flanges  28 ′″,  29 ′″,  30 ′″ and  31 ′″ are folded in a zigzag manner. The central space  52 ′″ is much smaller in this contracted state. 
         [0129]      FIG. 43  is an enlarged diagrammatic top view of a contracted state of the device  23 ′″ of  FIG. 42 , showing it compactly nested within a sleeve  79 ′″, with all four notches and flanges folded. The sleeve  79 ′″ carries the device  23 ′″ through a corneal incision into the eye. 
         [0130]      FIG. 44  is an enlarged diagrammatic top view of the device of  FIG. 42 , in nearly fully self expanded state showing the four notches  24 ′″,  25 ′″,  26 ′″, and  27 ′″ fully expanded and the flanges  28 ′″,  29 ′″,  30 ′″ and  31 ′″ nearly straightened. The central space  52 ′″ is also expanded. The device self-expands by moving from the shape of  FIG. 42  to the shape of  FIG. 37  due to shape memory. 
         [0131]      FIG. 45  is an enlarged diagrammatic top view of a contracted state of a device of the present invention made of shape memory self-enlarging material. The device  80 ′″ is a small closed ring formed from a tortuous strand. The notches and flanges are not discernible due to the tortuosity of the strand. 
         [0132]      FIG. 46  is an enlarged diagrammatic top view of a fully expanded state of the device of  FIG. 45 , showing notches  81 ′″,  82 ′″,  83 ′″, and  84 ′″ and straightened flanges  85 ′″,  86 ′″,  87 ′″ and  88 ′″. The device encloses a space  89 ′″. The circumference of the device of  FIG. 46  is larger than that of the device of  FIG. 45 . 
         [0133]      FIG. 47  is an enlarged diagrammatic top view of a contracted and open ring state of a device of the present invention made of self-enlarging, self-healing and self-reconfiguring programmable material showing device  90 ′″ with free ends  91 ′″ and  92 ′″. Sides  97 ′″,  98 ′″ and  99 ′″, connect notches  93 ′″,  94 ′″,  95 ′″ and  96 ′″. The device  90 ′″ partially encloses a space  100 ′″. 
         [0134]      FIG. 48  is an enlarged diagrammatic top view of a fully expanded and closed ring state of a device of the present invention formed by self-enlargement, self-healing and self-reconfiguration of the device  90 ′″ of  FIG. 47 , showing the free ends  91 ′″ and  92 ′″ coming together in a programmed manner and joining by self healing at joint  101 ′″ to form flange  102 ′″. The device completely encloses the space  100 . Notches  93 ′″,  94 ′″,  95 ′″ and  96 ′″ and flanges  97 ′″,  98 ′″ and  99 ′″ of the device of  FIG. 14  are larger than the corresponding notches and flanges of  FIG. 47 . 
         [0135]      FIG. 49  is an enlarged perspective view of a device  200  having four flanges  201 ,  202 ,  203  and  204 , all of which define a first plane. The four flanges  201 ,  202 ,  203  and  204  define four blind corners  205 ,  206 ,  207  and  208 , as illustrated in  FIG. 49 . All of the blind corners  205 ,  206 ,  207  and  208  define a second plane 0.1 to 0.5 mm above the first plane defined by the flanges  201 ,  202 ,  203  and  204 . Though not contained entirely in a single plane, the device  200  does not snag the incision because the notches defined by the blind corners  205 ,  206 ,  207  and  208  can completely straighten out as the device  200  negotiates the incision. The advantage of this embodiment is that the device conforms to the anterior convexity of the crystalline lens and iris. 
         [0136]      FIG. 50  is an enlarged perspective view of a device  300  having four flanges  301 ,  302 ,  303  and  304 . Flanges  301  and  303  define a first plane, while flanges  302  and  304  define a second plane, e.g., 0.1 to 0.5 mm above the first plane. The four flanges  301 ,  302 ,  303  and  304  define four blind corners  305 ,  306 ,  307  and  308 , as illustrated in  FIG. 50 . The blind corners  305 ,  306 ,  307  and  308  lie at either the first plane or second plane, or in between these planes. Though not entirely in a single plane, the device  300  does not snag the incision because the notches defined by the blind corners  305 ,  306 ,  307  and  308  can completely straighten out as the device negotiates the incision. The advantages of this embodiment are that alternate flanges are at a lower plane and are easily tucked under the pupil margin and there is less bending of the iris. 
         [0137]    In an alternate embodiment, the device may be employed as a long-term and/or permanent prosthetic. More particularly, the device may be placed in the eye as a prosthetic to achieve long-term pupil dilation. 
         [0138]    Although different ways of deforming the device have been described and illustrated, it is understood that the device may be deformed in other ways to serve the purpose. Although a square shaped configuration is described, it is understood that the present invention may have any polygonal shape, including a rectangular shape and a hexagonal shape. Although a closed ring configuration is described, it is understood that the present invention may be a closed ring, which can be converted to an open ring. It is also understood that the device may have an open ring configuration or an open ring configuration which can be converted to a closed ring. It is understood that the present invention may be placed in the eye using a forceps, Kuglen hook, or a delivery device like an Injector, Shooter or a Carrier, with or without the use of a cartridge. 
         [0139]    Those ordinarily skilled in the art can make changes in the embodiments described and illustrated, without altering the concepts of the present invention. Hence, it is to be understood that the invention is not limited to the descriptions, illustrations and examples, but includes all modifications within the scope of this invention.