WO2004041323A2 - Improved endocapsular tension ring and method of implanting same - Google Patents

Improved endocapsular tension ring and method of implanting same Download PDF

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Publication number
WO2004041323A2
WO2004041323A2 PCT/US2003/034296 US0334296W WO2004041323A2 WO 2004041323 A2 WO2004041323 A2 WO 2004041323A2 US 0334296 W US0334296 W US 0334296W WO 2004041323 A2 WO2004041323 A2 WO 2004041323A2
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WO
WIPO (PCT)
Prior art keywords
open loop
diameter
further
un
apparatus
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PCT/US2003/034296
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French (fr)
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WO2004041323A3 (en
Inventor
Jaime. Zacharias
Original Assignee
Yablon, Jay, R.
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Priority to US42212602P priority Critical
Priority to US60/422,126 priority
Priority to US48133903P priority
Priority to US60/481,339 priority
Application filed by Yablon, Jay, R. filed Critical Yablon, Jay, R.
Publication of WO2004041323A2 publication Critical patent/WO2004041323A2/en
Publication of WO2004041323A3 publication Critical patent/WO2004041323A3/en

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Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/14Eye parts, e.g. lenses, corneal implants; Implanting instruments specially adapted therefor; Artificial eyes
    • A61F2/147Implants to be inserted in the stroma for refractive correction, e.g. ring-like implants

Abstract

An improved endocapsular tension ring (36) and method of implanting same in a capsular bag (12) of a human eye (14). In one aspect of the invention, the improved endocapsular tension ring (10) includes an open-ended loop (36) formed of biocompatible material that is constructed to be resilient to compression in the radial direction within the capsular bag (12) to prevent shrinkage of the capsular bag (12) during and after intraocular surgery. The improved endocapsular tension ring (10) includes a plurality of anchoring points (40, 41) placed along the open loop extension allowing to transitorily place an inward bending element in the form of a running arc (72) or chord (48) during insertion of the capsular ring (10) into the eye (14). Methods and devices for implanting the improved endocapsular tension ring (10) in the capsular bag of a human eye are also disclosed.

Description

Improved Endocapsular Tension Ring and Method of Implanting Same

Field of the Invention

The present invention relates generally to eye implants for human eyes and, more particularly, to a capsular bag implant for stabilizing the capsular bag of a human eye during and after intraocular surgery.

Background of the Invention

The human eye is susceptible to various diseases and abnormalities that can lead to impaired vision in the eye. In severe cases of ocular disease or abnormality, near or total loss of functional vision may result which can only be restored through intraocular surgery.

For example, cataracts are caused by a gradual clouding of the lens and its surrounding material which, over an extended period, may result in complete loss of functional sight in the cataractous eye. Intracapsular cataract extraction includes complete removal of the lens, the capsular bag enveloping the lens, by section of the zonules connecting the capsular bag to the ciliary body near the scleral wall of the eye. Following this modality of cataract removal, an artificial intraocular lens (lOL) is then implanted in the anterior chamber of the eye, with the haptics of the IOL being received in the anterior chamber angle region between the iris and the cornea. Alternatively, the IOL can be fixated to the iris or to the scleral wall in the posterior chamber, with the haptics of the IOL resting between the iris and the ciliary body.

Extracapsular cataract extraction is performed to remove the cataractous lens while leaving the capsular bag and zonules intact within the posterior chamber of the eye. In this procedure, a capsulotomy incision is performed to remove a preferably circular mid-portion of the anterior capsule of the capsular bag in the way of a capsulorhexis, thereby leaving the posterior capsule, an annular anterior capsular flap and a generally circular anterior capsulorhexis edge.

The cataractous lens is removed from the residual capsular bag and replaced with an artificial IOL. The IOL has haptics to engage an inner peripheral surface of the residual capsular bag and centralize the IOL within the capsular bag. Those skilled in the art of ophthalmic surgical procedures will appreciate that the capsular bag is a delicate elastic membrane that envelops the lens. The capsular bag is connected to the ciliary body near the scleral wall of the eye through zonule fibers that function to centralize the lens behind the iris and in alignment with the pupil. In eye patients with missing or damaged zonules from trauma or disease, the position of the capsular bag within the posterior chamber of the eye is unstable, making removal of the enclosed cataractous lens difficult and implantation of the IOL challenging. In the past, capsular bag implants have been developed to stabilize the capsular bag during the extracapsular cataract extraction procedure and to generally centralize the capsular bag within the posterior chamber of the eye in patients having limited damaged or missing zonules. Known capsular bag implants, commercially available from Morcher GmbH of Stuttgart, Germany, under model designations Type 14, 14A and 14C, and from Ophtec, USA, under model designations Type PC-275 and PC-276 have been found to be successful in preventing shrinkage of the elastic capsular bag during the cataract extraction procedure and to improve stabilization of the intraocular environment in some patients with limited zonular dialysis or zonular weakness. The Morcher and Ophtec capsular bag implants (endocapsular tension rings or CTRs) comprise an open- ended loop of polymethyl methacrylate (PMMA) which is resilient to compression in the radial direction within the capsular bag. The capsular bag implants are adapted to be implanted in the residual capsular bag before or after the cataractous lens is removed, and to engage the inner peripheral surface of the residual capsular bag to prevent shrinkage.

The general circular expansion of the capsular bag as provided by the capsular bag implant improves stabilization of the intraocular environment and lens centration during intraocular surgery in patients with limited zonular dialysis or generalized zonular weakness. The capsular bag implant may be sutured to the scleral wall of the eye by passing a loop around the endocapsular tension ring and then passing the suture through the annular anterior capsulorhexis flap or the peripheral edge of the capsular bag.

A modified endocapsular tension ring introduced by Cionni (US pat. 5,843, 184) provides a fixation element (referred to herein as a "Cionni fixation element") having one end fixed to the open-ended loop and a free end which preferably terminates in an eyelet. The eyelet of the fixation element is operable to receive a suture for attachment of the fixation element to the scleral wall of the eye and thereby stabilize and centralize the capsular bag within the posterior chamber of the eye.

Endocapsular tension rings are implanted through an eventually small incision (less than 3.3 mm wide). Capsular tension rings usually have one eyelet at each end of the open loop. The implantation process can be performed by direct manipulation of the endocapsular tension ring using delicate microsurgical forceps. As an alternative, dedicated endocapsular tension ring injectors that act in a syringe-like fashion, deliver the endocapsular tension ring inside the eye through a cannula upon compression of a plunger with a hook that holds the endocapsular tension ring by the trailing eyelet.

Regardless whether the endocapsular tension ring is manually implanted or implanted using currently available injectors, the ring is forced to follow the inner peripheral surface of the capsular bag guided by the same capsule. It is of common occurrence that the leading portion of the endocapsular tension ring travels within the eye at an angle excessively perpendicular to the inner peripheral surface of the capsular bag, inconvenient for a safe endocapsular delivery of the tension ring.

Notwithstanding the advancements made in the prior art in the field of endocapsular bag implants, there is a need for an endocapsular tension ring implant which facilitates the implantation process and improves safety during the same.

Summary of Invention

To these ends, the present invention sets forth an improved endocapsular tension ring and method of implanting same which is particularly adapted to facilitate implantation and to provide enhanced protection to the integrity of the capsular bag and zonular suspensory ligament during the implantation process. In one embodiment of the invention, the improved endocapsular tension ring includes an open-ended loop formed of biocompatible material.

The open-ended loop is constructed to be resilient to compression in the radial direction within the capsular bag to prevent shrinkage of the capsular bag during and after intraocular surgery and to allow elastic deformation during the implantation process. A novel aspect of the invention includes a series of intermediate inward bending element anchoring structures ("intermediate anchoring elements") placed along the open loop body each of them preferably comprising a suitably sized eyelet.

The inward bending element anchoring structures provide fixation points for at least one running inward bending element comprising in a preferred embodiment a blunt ended wire of a high memory flexible material such as nitinol or stainless steel. The open-ended loop of the improved endocapsular tension ring generally lies in a plane, and the inward bending element anchoring structures preferably extend inwardly from the loop towards the center of the plane. In an alternative embodiment, a running chord (such as but not limited to a suture chord) is threaded through the anchoring elements.

During an extracapsular cataract extraction, the improved endocapsular tension ring has to be carefully implanted inside the capsular bag. In one preferred method of implantation an inward bending element in the form of a high memory flexible wire is passed in sequence through the anchoring structures.

The inward bending element is retracted inside the lumen of an inserter cannula loaded with the endocapsular tension ring. The implantation process considers careful placement of the inserter cannula through a surgical wound into the eye. By pushing a plunger of the inserter, the endocapsular ring open loop is delivered together with the inward bending element in a reduced loop diameter, facilitating implantation and allowing an implantation process free of stress to the capsule and zonules.

To complete the implantation of the endocapsular ring into the capsular bag, the inward bending element is retracted inside the inserter cannula releasing the endocapsular ring. The endocapsular ring is released because the rim of the tip of the inserter cannula acts as a stopper preventing the ring to re-enter the cannula together with the inward bending element. In another method of implementation, a suture is passed through one eyelet and then sequentially passed through the other chord anchoring points and passed in reverse order back to the origin and tied forming a chord loop suitable to be tensioned. The implantation process initially considers tensioning the suture to reduce the loop diameter followed by careful placement of the reduced diameter endocapsular tension ring through a surgical wound into the eye facilitating implantation and allowing and implantation process free of stress to the capsule and zonules. By pulling the suture loop, the endocapsular ring open loop progressively reduces the loop diameter.

To complete the implantation of the endocapsular ring into the capsular bag, the running chord loop can be cut or untied for endocapsular ring expansion and tensing chord removal. Alternatively, a specially designed suitable injector can be used to automatically provide the adequate traction to the string loop during each step of the endocapsular tension ring delivery process. Regardless of embodiment, Instead of the open loop using the capsular bag inner peripheral surface as a guide for the final positioning, the loop expands in a centrifugal fashion inside the capsular bag to attain the final position only exerting radial force to the capsular bag equator. That is, the endocapsular ring then expands up to the capsule equator using its own elastic force.

The improved endocapsular tension ring is implanted to prevent shrinkage of the capsular bag. Transitory use of the anchoring points to pass an inward bending element or running chord or other equivalent element that reduces the open loop total diameter during implantation makes the implantation procedure controlled and safe.

The above features and advantages of the present invention will be better understood with reference to the accompanying figures and detailed description.

Brief Description of Drawings

The features of the invention believed to be novel are set forth in the appended claims. The invention, however, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawing(s) summarized below.

FIG. 1 (Prior Art) is a top plan view of a capsular tension ring corresponding to the prior art. FIG. 2 (Prior Art) is a top plan view of a capsular tension ring comprising the Cionni fixation element of

US Patent 5,843, 184. FIG. 3 (Prior Art) is a top plan view of a capsular tension ring of the prior art partially emerging from a capsular tension ring injecting device.

FIG. 4 is an illustration of a human eye, partially in cross-section, showing an already implanted improved endocapsular tension ring of the present invention in a residual capsular bag in its final position. FIG. 5 is a top plan view of the main embodiment of the improved endocapsular tension ring of the present invention shown in resting position.

FIG. 6 is an expanded view of one embodiment of a single inward bending element anchoring structures of an endocapsular ring of the present invention.(A.-side view, B.- top plan view and C- sectional view).

FIG. 7 is an expanded view of another embodiment of a single inward bending element anchoring structures of an endocapsular ring of the present invention. (A.-side view, B.- top plan view and C- sectional view). FIG. 8 is an expanded view of a terminal eyelet designed to act as an inward bending element anchoring structure of an endocapsular ring of the present invention.( A.- top plan view and B.-side view).

FIG. 9 is a top plan view of an alternative embodiment of the improved endocapsular tension ring shown in FIG. 5 here applied to a capsular ring with the Cionni modification (US pat. 5,843,184). FIG. 10 shows a custom designed intracapsular tension ring injector device specially suited for intraocular injection of the intracapsular tension ring of the present invention. (A.- general side view and B.-distal end expanded view).

FIG. 1 1 shows the distal end of a custom designed endocapsular tension ring injector device specially suited for intraocular injection of the endocapsular tension ring of the present invention during four different stages of the endocapsular delivery process.

FIG. 12 is a top plan view of the improved endocapsular tension ring of FIG. 5 shown with tension applied to the tensing chord.

FIG. 13 is a top plan view of the improved endocapsular tension ring of FIG. 5 shown at four different stages of the endocapsular delivery process using a specially designed endocapsular tension ring injector device. FIG. 14 is a fragmentary top view of a residual capsular bag following a capsulorhexis procedure, showing an already implanted improved endocapsular tension ring of the present invention and an artificial intraocular lens in the capsular bag.

FIG. 15 is a plan view illustrating the actual injection of the endocapsular tension ring into the eye using the injector of FIG. 13, and in particular shows in views A and B how the reduced diameter eliminates any stress on the capsular equator during insertion, and view C shows the safe radial expansion of the endocapsular tension ring to support the equator after insertion.

FIG. 16 is a plan view illustrating the manipulation of the endocapsular tension ring using a positioning instrument such as, but not limited to, a Kuglen Iris Hook / Lens Manipulator.

FIG. 17 is a plan view illustrating an alternative embodiment of the invention in which some or all of the circumferential length of the endocapsular tension ring is hollow, effectively creating an infinite number of anchoring elements running along the inner circumference of the hollow regions.

Figure Numerals: endocapsular tension ring 10, capsular bag 12, human eye 14, posterior chamber 16, iris 18, pupil 20, ciliary body 22, zonules 24, scleral wall 25, anterior capsule 26, posterior capsule 28, capsular flap 30, capsulorhexis edge 32, surgical incision 33, artificial intraocular lens (IOL) 34, open-ended loop 36, terminal (spaced) ends 38, terminal eyelets 40, intermediate eyelets 41 , inner peripheral surface 42, Cionnni fixation element 44, inter-eyelets loop arcs 46, chord 48, injector tube 50, chord knot 52, fixation element free end 56, eyelet 57, fixation element end 58, haptic members 60, injector tube 70, flexible wire 72, blunt tip 74, injector body 76, injecting device 80, injector tip rim 82, plunger 84, spring 86, widening 88, positioning instrument 160.

Detailed Description With reference to FIG. 4 , an improved endocapsular tension ring 10 in accordance with one embodiment of the present invention is shown implanted in a capsular bag 12 of a human eye 14.

As will be described in more detail below, the improved endocapsular tension ring 10 of the present invention is particularly adapted to improve easiness of insertion and safety, particularly in patients that suffer from weak, missing or damaged zonules. In a normal human eye, the lens of the eye (not shown) is enveloped in the capsular bag 12 which is positioned centrally in the posterior chamber 16 of the eye behind the iris 18 and aligned with the pupil 20.

The capsular bag 12 is an elastic membrane or pouch having a generally circular cross-section taken along a horizontal plane, and is attached to the ciliary body 22 of the eye through a series of zonules 24. The ciliary body 22 is attached to the scleral wall 25 of the eye. The zonules 24 are thin fibers that function to centralize the capsular bag 12 and its enveloped lens in a normal anatomic position within the posterior chamber 16 of the eye.

As shown in FIG. 4, the improved endocapsular tension ring 10 of the present invention is particularly adapted to be implanted in the capsular bag 12 for long term stabilization of the capsular bag 12 during and after intraocular surgery. The capsular bag 12 of FIG. 4 is illustrated as a residual capsular bag which remains following a capsulorhexis procedure commonly performed during intraocular surgery to remove a cataractous lens. During the capsulorhexis surgical procedure, an incision is made in the anterior capsule 26 of the capsular bag 12 to remove a generally circular mid-portion of the anterior capsule 26. Following this procedure, the residual capsular bag 12 includes a posterior capsule 28, an annular anterior capsular flap 30, and a generally circular capsulorhexis edge 32 as shown most clearly in FIG. 4.

As described in detail below, the residual capsular bag 12 is able to retain the improved endocapsular tension ring 10 and an artificial intraocular lens (IOL) 34 (FIG. 14) within the capsular bag 12 following the capsulorhexis procedure.

Referring now to FIGS. 5-14, the improved endocapsular tension ring 10 according to several embodiments of the present invention includes an open-ended loop 36 of biocompatible material having spaced ends 38, 38 terminating in respective terminal anchors, e.g., eyelets 40, 40. One or more anchoring elements e.g., intermediate eyelets 41 are spaced along open loop 36 acting as anchoring points for an inward bending element to be discussed further below.

The open-ended loop 36 is adapted to be safely implanted in the residual capsular bag 12 of eye 14 to prevent shrinkage of the capsular bag 12 during and after intraocular surgery. One embodiment of intermediate eyelets 41 is depicted in FIG. 6. Radial view (FIG. 6A), top plan view (FIG. 6B) and sectional view (FIG. 6C). This configuration is suitable for passage of inward bending element 72 parallel to the plane of endocapsular tension ring 10.

A preferred embodiment of intermediate eyelets 41 is depicted in FIG. 7. Radial view (FIG. 7A), top plan view (FIG. 7B) and sectional view (FIG. 7C). This configuration is suitable for passage of inward bending element 72 and also suitable for use as anchoring points for positioning instruments usually acting perpendicular to the plane of endocapsular tension ring 10.

This embodiment is also easier to manufacture using current ring manufacturing techniques. A preferred embodiment for terminal eyelets 40 is depicted in an expanded view in FIG. 8. This design (FIG. 8A top plan view and FIG. 8B side view) allows eyelet 40 to act as an inward bending element anchoring structure and as an instrument anchoring point.

It is clear from FIGS. 7 and 8 that the embodiments illustrated in these figures comprise a passageway with components both parallel to and perpendicular to a plane of open loop 36. More particularly, the open-ended loop 36 is implanted between the posterior capsule 28 and the annular anterior capsular flap 30 to engage an inner peripheral surface 42 proximate the equator of the capsular bag 12 and to maintain a predetermined diameter of the capsular bag 12. The open-ended loop 36 is generally flexible to resist compression in a radial direction within the capsular bag 12 (FIG. 14).

Preferably, the open-ended loop 36 has an un-flexed diameter of about 12 mm and a radially inward flexed diameter of about 10 mm when implanted properly in final position, although other diameters of open-ended loops 36 are possible without departing from the spirit or scope of the present invention.

The open-ended loop 36 is preferably made of polymethylmethacrylate (PMMA), although those skilled in the art will appreciate that other biocompatible materials suitable for implantation in a capsular bag 12 can also be considered. During intraocular surgery to remove a cataractous lens, and in accordance with a preferred implantation method of the present invention, a capsulorhexis procedure is first performed to form the residual capsular bag 12 having the posterior capsule 28, annular anterior capsular flap 30 and capsulorhexis edge 32.

In a preferred mode for implantation, a specially designed capsular tension ring injecting device 80 (FIGS. 10-1 1) can be used for intraocular delivery of capsular tension ring 10. Injecting device 80 has a plunger 84 acting against a spring 86 to displace a high memory flexible wire 72 made of a material such as nitinol or stainless steel extended inside an injector tube.

Flexible wire 72 is contained within an injector tube 50 extended into a near linear configuration. When flexible wire 72 is displaced outside distal end 70 it is free to curve to achieve its pre-shaped small diameter curve. The memory shape has been calculated to provide a small diameter circular shape with the proper force to inward bend the open loop of endocapsular tension ring 10 to a desired diameter preferably between 4 and 10 mm.

Flexible wire 72 has a distal blunt tip 74 to prevent damage to intraocular structures. The bending effect is obtained when outside of injector tube lumen because flexible wire 72 has been threaded through anchoring elements 40 and 41. Endocapsular tension ring 10 is loaded inside injector tube 70 with flexible wire 72 threaded through anchoring elements 40 and 41. The loaded injector 80 is inserted through a surgical incision 33 inside the capsular bag 12. A widened section 88 of flexible wire 72 prevents passage through trailing eyelet 40. In this way pushing plunger 84 of inserter 80 delivers endocapsular tension ring 10 in a reduced diameter inside capsular bag 12.

Releasing plunger 84 of injector 80 totally retracts flexible wire 72 inside injector tube 70 in a way that endocapsular tension ring 10 remains inside the capsular bag free to expand. Injector tube 70 is then withdrawn from the eye.

On another method for implantation eyelets 40 and 41 can be used as anchoring points for one or more positioning instruments 160 used to produce an inward bending of inter-eyelet loop arcs 46 to facilitate introduction of endocapsular tension ring 10 inside capsular bag 12.

On yet another alternative method for implantation (FIG. 12) a running chord 48 is threaded through eyelets 40, 41 preferably in sequence from one terminal eyelet 40 to the terminal eyelet 40 of the opposite end and then threaded back to the origin passing through intermediate eyelets 41. Running chord 48 may be composed of suture material such as nylon 1 1-0 monofilament. It will be appreciated that other suture diameters and materials are possible without departing from the spirit or scope of the present invention. Open ended loop 36 maintains its un-flexed radial diameter while running chord 48 is kept un-tensed.

Progressively tensing running chord 48 flexes radially open ended loop 36 coiling around itself and progressively reducing its diameter down to 8 millimeters and below. After running chord 48 has been tensed to achieve a desired open loop 36 diameter below the unflexed diameter that is adequate for easy implantation into an eye 14 capsular bag 12, running chord 48 loop is locked by tying a knot 52 as shown in FIG. 12 or by using other locking mechanisms such as displacement of a tight sleeve surrounding the suture ends.

In this way the reduced diameter of open loop 36 is kept stable during implantation. The endocapsular tension ring 10 is delivered into an eye 14 through a surgical incision 33 by carefully dialing in a first terminal end 38 and continuing with the rest of the open loop 36 until complete introduction into the eye 14.

Once capsular tension ring 10 is in suitable position, tension is relieved from running chord 48 by sectioning or untying producing the radial expansion of the open loop 36 inside the capsular bag 12 that remains with a slight degree of radial inward flexion produced by contact with inner peripheral surface 42 of capsular bag 12. Running chord 48 is removed from the eye 14 after capsular tension ring 10 delivery by softly puling one end of the loose tensing chord 48 to un-thread it from all eyelets 40, 41.

On yet another method of implantation a specially designed ring injector (FIG. 13) pushes capsular tension ring 10 out of a cannula into an eye 14 while maintaining a variable degree of tension on a threaded tensing chord 48 during the delivery process. A variable calculated tension applied to tensing chord 48 has been calculated to regulate the amount of radial inward flexion of the open loop 36 inside the eye 14 during insertion, and preferably to obtain a spiral or tight circular path of displacement of the open loop 36 into the capsular bag 12 that facilitates atraumatic capsular tension ring 10 delivery.

The improved endocapsular tension ring 10 is implanted in the residual capsular bag 12 of eye 14 between the posterior capsule 28 and the annular anterior capsular flap 30. The open-ended loop 36 is operable to generally prevent shrinkage of the capsular bag 12 as the loop 36 engages the inner peripheral surface 42 of the capsular bag 12.

Where the natural lens (not shown) is to be replaced by an IOL, the IOL 34 shown in FIG. 14 is implanted in the capsular bag 12 which is stabilized by the improved endocapsular tension ring 10. The IOL 34 typically includes haptic members 60 which engage the inner peripheral surface 42 of the capsular bag 12.

Modified capsular tension rings such as the one described in US. PAT 5.843.184 (Cionni) are not suitable for insertion using standard injectors. This because a Cionni fixation element 44 is fixed to open loop 36 and has a free end 56 terminating in an eyelet 57 to be sutured to a scleral wall 25.

Cionni fixation element 44 impedes full loading of the capsular tension ring into an injector for intraocular delivery. FIG. 9 shows such a Cionni-modified endocapsular tension ring 10 with the addition of the intermediate open loop 36 chord anchoring eyelets 41 which are embodiments of the present invention.

The use of a bending wire 72 or of a tensing chord 48 threaded across eyelets 41 to reduce the radial diameter during endocapsular insertion of this modified ring yields results particularly helpful for implantation.

Those skilled in the art will readily appreciate that the improved endocapsular tension ring 10 of the present invention advantageously facilitates intraocular implantation and prevents shrinkage of the capsular bag 12 during and after intraocular surgery. From the above disclosure of the general principles of the present invention and the preceding detailed description of preferred embodiments, those skilled in the art will readily comprehend the various modifications to which the present invention is susceptible.

For example, intermediate inward bending element anchoring structures 41 may be conformed by eyelets of different configurations, size and orientation. The number of intermediate anchoring points 41 may vary, as well as their relative position in the open ended loop 36.

Alternative anchoring elements may be used instead of eyelets such as hooks, spirals or others of varying configurations and composition to facilitate inward bending element placement, displacement and removal. The composition, shape and structure of the inter-eyelet loop arcs 46 may vary in a same device to provide differential elastic and compression characteristics along the loop full arc to produce different patterns of radial inward flexion of the open loop.

FIG. 17 illustrates one such embodiment in which some or all of the circumferential length of the endocapsular tension ring is hollow 208, effectively creating an infinite number of anchoring elements running along the inner circumference of the hollow regions. In this embodiment, for example, inward bending element 72 (e.g., flexible memory wire) is introduced inside the tube opening for insertion, and later removed (withdrawn) after ring 10 has been properly inserted into the capsular bag 12. This tube-shaped ring can be open at one (as shown) or both ends for introducing inward bending element 72 and can have added optional fenestrations 210 such as slits, holes, etc. along the ring loop for improved fluid circulation. The tube-like portion may comprise a single hollow 208 (as shown) or be divided into a plurality of tube shaped segments. In such an embodiment, the anchoring elements 41 are maximized to cover to the full extent of the inner circumference of the inner wall 204 of the tube ring.

Optional fenestrations 210 can be added to the walls of this hollow, tube-shaped ring embodiment to allow improved exchange of fluid with the inner portion or lumen of the tube ring. The exchange of fluids can be helpful in a plurality of ways. For example it can avoid the presence of a sequestered cavity by providing oxygen and immune system cells to prevent the growth of germs which otherwise could lead to an intraocular infection. The fenestrations also facilitate the introduction and withdrawal of the inward bending memory wire into the ring lumen by reducing conditions that could lead to a pressure (introduction) or vacuum (withdrawal) effect. Also, this tube-shaped ring embodiment may be loaded with and used as a vehicle for the slow release of a therapeutic agent 212, with a suitable disposition of fenestrations 210 regulating a desired rate of release of this therapeutic agent 212 into the aqueous humor of the eye. Finally, fenestrations 210 may also serve as anchoring elements in the same way as the intermediate eyelets 41, particularly so for, but not limited to, positioning instruments 160.

The invention in its broader aspects is therefore not limited to the specific details and illustrative example shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of Applicant's general inventive concept. The features of the invention believed to be novel are set forth in the appended claims. The invention, however, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawing(s) summarized below.

Claims

Claims: 1. An endocapsular tension ring apparatus, comprising: an open loop (36) comprising terminal ends (38) thereof and an un-flexed diameter thereof; and at least one intermediate anchoring element (41 ) fixed to said open loop (36) and displaced from each of said terminal ends (38) wherein tension applied to said at least one intermediate anchoring element (41) is capable of reducing a diameter of said open loop (36) to a flexed diameter below said un-flexed diameter to for insertion of said open loop (36) into a capsular bag ( 12).
2. The apparatus of claim 1 , wherein: said diameter of said open loop (36) is enabled to expand toward said un-flexed diameter by relieving said tension after said reduced-diameter open loop (36) is inserted into said capsular bag ( 12).
3. The apparatus of claim 1 , further comprising: terminal anchoring elements (40) fixed to and terminating said terminal ends (38) of said open loop (36).
4. The apparatus of claim 1 , said at least one intermediate anchoring element (41) comprising a plurality of intermediate anchoring elements (41 ).
5. The apparatus of claim 4, said plurality of intermediate anchoring elements (41) comprising a hollow (208) within at least part of a circumferential length of said open loop (36).
6. The apparatus of claim 5, said open loop (36) further comprising a plurality of fenestrations (210).
7. The apparatus of claim 6, further comprising a therapeutic agent (212) loaded within said hollow (208) and released through said fenestrations (210).
8. The apparatus of claim 1 , further comprising: at least one Cionni fixation element (44) fixed at a first end thereof to said open loop (36) and comprising a second free end thereof.
9. The apparatus of claim 8, further comprising: at least one said intermediate anchoring element (41) fixed to said open loop (36) where said at least one Cionni fixation element (44) is also fixed to said open loop (36).
10. The apparatus of claim 1 , said at least one intermediate anchoring element (41 ) comprising an eyelet.
1 1. The apparatus of claim 1 , said at least one intermediate anchoring element (41 ) comprising at least one fenestration (210).
12. The apparatus of claim 1 , said at least one intermediate anchoring element (41 ) directed inwardly with respect to a circumference of said open loop (36).
13. The apparatus of claim 10, said eyelet comprising: a passageway substantially perpendicular to a plane of said open loop (36).
14. The apparatus of claim 10, said eyelet comprising: a passageway substantially parallel to a plane of said open loop (36).
15. The apparatus of claim 10, said eyelet comprising: a passageway with components both parallel to and perpendicular to a plane of said open loop (36).
16. The apparatus of claim 1 , said at least one intermediate anchoring element (41) comprising a hook.
17. The apparatus of claim 1, said at least one intermediate anchoring element (41) comprising a spiral.
18. The apparatus of claim 3, said terminal anchoring elements (40) comprising eyelets.
19. The apparatus of claim 18, said eyelet comprising: a passageway with components both parallel to and perpendicular to a plane of said open loop (36).
20. The apparatus of claim 1 , further comprising: a running chord (48) threaded through said at least one intermediate anchoring element (41).
21. The apparatus of claim 3, further comprising: a running chord (48) threaded through said at least one intermediate anchoring element (41 ) and said terminal anchoring elements (40).
22. The apparatus of claim 20, further comprising: tension applied to said running chord (48) reducing said diameter of said open loop (36) below said un- flexed diameter.
23. The apparatus of claim 22, said tension applied to said running chord (48) comprising a variable tension calculated to regulate an inward flexion of said open loop (36) below said un-flexed diameter.
24. The apparatus of claim 20, further comprising: tension relieved from said running chord (48) enabling said diameter of said open loop (36) to expand toward said un-flexed diameter.
25. The apparatus of claim 1 , further comprising: an inward bending element (72) threaded through said at least one intermediate anchoring element (41).
26. The apparatus of claim 3, further comprising: an inward bending element (72) threaded through said at least one intermediate anchoring element (41) and said terminal anchoring elements (40).
27. The apparatus of claim 25, further comprising: tension in said inward bending element (72) reducing said diameter of said open loop (36) below said un- flexed diameter.
28. The apparatus of claim 25, further comprising: retraction of said inward bending element (72) from said open loop (36), enabling said diameter of said open loop (36) to expand toward said un-flexed diameter.
29. The apparatus of claim 25, said inward bending element (72) comprising a flexible memory wire for reducing said diameter of said open loop (36) below said un-flexed diameter.
30. The apparatus of claim 1 , further comprising: at least one positioning instrument (160) anchoring to said at least one intermediate anchoring element (41) and used to reduce said diameter of said open loop (36) below said un-flexed diameter.
31. The apparatus of claim 3, further comprising: at least one positioning instrument (160) anchoring to said at least one intermediate anchoring element (41) and said terminal anchoring elements (40) and used to reduce said diameter of said open loop (36) below said un- flexed diameter.
32. The apparatus of claim 20 in combination with an injecting device (80): said injecting device (80) containing said open loop (36) and said running chord (48) threaded therethrough.
33. The combination of claim 32, further comprising: tension applied to said running chord (48) to maintain said diameter of said open loop (36) below said un- flexed diameter while pushing said open loop (36) and said running chord (48) together out of said injecting device (80), during an injection of said open loop (36) into said capsular bag (12).
34. The combination of claim 33, said tension applied to said running chord (48) comprising a variable tension calculated to regulate an inward flexion of said open loop (36) below said un-flexed diameter.
35. The combination of claim 33, said injecting device (80) further comprising: said tension relieved from said running chord (48) enabling said diameter of said open loop (36) to expand toward said un-flexed diameter, following said injection of said open loop (36) into said capsular bag (12).
36. The apparatus of claim 25 in combination with an injecting device (80): said injecting device (80) containing said open loop (36) and said inward bending element (72) threaded therethrough.
37. The combination of claim 36, further comprising: tension provided by said inward bending element (72) to maintain said diameter of said open loop (36) below said un-flexed diameter while pushing said open loop (36) and said inward bending element (72) together out of said injecting device (80), during an injection of said open loop (36) into said capsular bag (12).
38. The combination of claim 37, further comprising: retraction of said inward bending element (72) from said open loop (36) to relieve said tension, enabling said diameter of said open loop (36) to expand toward said un-flexed diameter, following injection of said open loop (36) into said capsular bag (12).
39. A endocapsular tension ring apparatus, comprising: an open loop (36) comprising terminal ends (38) thereof and an un-flexed diameter thereof; and a flexible memory wire reducing said diameter of said open loop (36) to a flexed diameter below said un- flexed diameter to for insertion of said open loop (36) into a capsular bag (12).
40. The apparatus of claim 39, wherein: said diameter of said open loop (36) is enabled to expand toward said un-flexed diameter by retracting said flexible memory wire after said reduced-diameter open loop (36) is inserted into said capsular bag (12).
41. A method of inserting an endocapsular tension ring apparatus into a capsular bag (12), comprising the steps of: providing an open loop (36) comprising terminal ends (38) thereof and an un-flexed diameter thereof; reducing a diameter of said open loop (36) to a flexed diameter below said un-flexed diameter by applying tension to at least one intermediate anchoring element (41) displaced from each of said terminal ends (38); and inserting the reduced-diameter open loop (36) into said capsular bag (12).
42. The method of claim 41 , further comprising the step of: enabling said diameter of said open loop (36) to expand toward said un-flexed diameter by relieving said tension after inserting said reduced-diameter open loop (36) into said capsular bag (12).
43. The method of claim 41 , further comprising the step of: applying said tension to said terminal ends (38) via terminal anchoring elements (40) fixed to and terminating said terminal ends (38) of said open loop (36).
44. The method of claim 41 , said step of reducing said diameter further comprising the step of: applying said tension to a plurality of intermediate anchoring elements (41 ) displaced from each of said terminal ends (38)
45. The apparatus of claim 44, said step of reducing said diameter further comprising the step of: applying said tension to said plurality of intermediate anchoring elements (41) comprising a hollow (208) within at least part of a circumferential length of said open loop (36).
46. The apparatus of claim 45, further comprising the step of: providing a plural ity of fenestrations (210) of said open loop (36).
47. The apparatus of claim 46, further comprising the steps of: loading a therapeutic agent (212) loaded within said hollow (208); and releasing said therapeutic agent (212) through said fenestrations (210).
48. The method of claim 41 , further comprising the step of: providing at least one Cionni fixation element (44) fixed at a first end thereof to said open loop (36) and comprising a second free end thereof.
49. The method of claim 48, further comprising the step of: applying said tension to at least one said intermediate anchoring element (41) fixed to said open loop (36) where said at least one Cionni fixation element (44) is also fixed to said open loop (36).
50. The method of claim 41 , said at least one intermediate anchoring element (41) comprising an eyelet.
51. The method of claim 41 , said step of reducing said diameter further comprising the step of: applying said tension to said at least one intermediate anchoring element (41) comprising at least one fenestration (210).
52. The method of claim 41 , further comprising the step of: providing said at least one intermediate anchoring element (41) directed inwardly with respect to a circumference of said open loop (36).
53. The method of claim 50, further comprising the step of: directing a passageway of said eyelet substantially perpendicular to a plane of said open loop (36).
54. The method of claim 50, further comprising the step of: directing a passageway of said eyelet substantially parallel to a plane of said open loop (36).
55. The method of claim 50, further comprising the step of: directing a passageway of said eyelet both parallel to and perpendicular to a plane of said open loop (36).
56. The method of claim 41 , said at least one intermediate anchoring element (41 ) comprising a hook.
57. The method of claim 41 , said at least one intermediate anchoring element (41) comprising a spiral.
58. The method of claim 43, said terminal anchoring elements (40) comprising eyelets.
59. The method of claim 58, further comprising the step of: directing a passageway of said eyelet both parallel to and perpendicular to a plane of said open loop (36).
60. The method of claim 41 , further comprising the step of: threading a running chord (48) through said at least one intermediate anchoring element (41 ).
61. The method of claim 43, further comprising the step of: threading a running chord (48) through said at least one intermediate anchoring element (41) and said terminal anchoring elements (40).
62. The method of claim 60, said step of reducing said diameter by applying tension further comprising the step of: reducing said diameter of said open loop (36) below said un-flexed diameter by tensing said running chord (48).
63. The method of claim 62, said step of tensing said running chord further comprising the step of: applying a variable tension to said running chord (48) calculated to regulate an inward flexion of said open loop (36) below said un-flexed diameter.
64. The method of claim 60, further comprising the step of: enabling said diameter of said open loop (36) to expand toward said un-flexed diameter, by relieving tension from said running chord (48).
65. The method of claim 41 , further comprising the step of: threading an inward bending element (72) through said at least one intermediate anchoring element (41 ).
66. The method of claim 43, further comprising the step of: threading an inward bending element (72) through said at least one intermediate anchoring element (41) and said terminal anchoring elements (40).
67. The method of claim 65, said step of reducing said diameter by applying tension further comprising the step of: reducing said diameter of said open loop (36) below said un-flexed diameter using tension in said inward bending element (72).
68. The method of claim 65, enabling said diameter of said open loop (36) to expand toward said un-flexed diameter, by retracting said inward bending element (72).
69. The method of claim 65, said inward bending element (72) comprising a flexible memory wire for reducing said diameter of said open loop (36) below said un-flexed diameter.
70. The method of claim 41 , further comprising the steps of: anchoring at least one positioning instrument (160) to said at least one intermediate anchoring element (41); and using the anchored positioning instrument (160) to reduce said diameter of said open loop (36) below said un-flexed diameter.
71. The method of claim 43, further comprising the steps of: anchoring at least one positioning instrument (160) to said at least one intermediate anchoring element (41) and said terminal anchoring elements (40); and using the anchored positioning instrument (160) to reduce said diameter of said open loop (36) below said un-flexed diameter.
72. The method of claim 60, further comprising the step of: containing said open loop (36) and said running chord (48) threaded therethrough in an injecting device (80).
73. The method of claim 72, further comprising the step of: maintaining said diameter of said open loop (36) below said un-flexed diameter while pushing said open loop (36) and said running chord (48) together out of said injecting device (80), during an injection of said open loop (36) into said capsular bag (12), by tensing said running chord (48).
74. The method of claim 73, said step of tensing said running chord further comprising the step of: applying a variable tension to said running chord (48) calculated to regulate an inward flexion of said open loop (36) below said un-flexed diameter.
75. The method of claim 73, further comprising the step of: enabling said diameter of said open loop (36) to expand toward said un-flexed diameter, following said injection of said open loop (36) into said capsular bag (12), by relieving said tension from said running chord (48).
76. The method of claim 65, further comprising the step of: containing said open loop (36) and said inward bending element (72) threaded therethrough in an injecting device (80).
77. The method of claim 76, further comprising the step of: maintaining said diameter of said open loop (36) below said un-flexed diameter while pushing said open loop (36) and said inward bending element (72) together out of said injecting device (80), during an injection of said open loop (36) into said capsular bag (12), using tension provided by said inward bending element (72).
78. The method of claim 77, further comprising the step of: enabling said diameter of said open loop (36) to expand toward said un-flexed diameter, following said injection of said open loop (36) into said capsular bag (12), by retracting said inward bending element (72).
79. A method of inserting an endocapsular tension ring apparatus into a capsular bag (12), comprising the steps of: providing an open loop (36) comprising terminal ends (38) thereof and an un-flexed diameter thereof; reducing a diameter of said open loop (36) to a flexed diameter below said un-flexed diameter using a flexible memory wire; and inserting the reduced-diameter open loop (36) into said capsular bag (12).
80. The method of claim 79, further comprising the step of: enabling said diameter of said open loop (36) to expand toward said un-flexed diameter by retracting said flexible memory wire after inserting said reduced-diameter open loop (36) into said capsular bag (12).
PCT/US2003/034296 2002-10-30 2003-10-30 Improved endocapsular tension ring and method of implanting same WO2004041323A2 (en)

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