REFERENCE TO RELATED APPLICATIONS

This application is a 371 national phase entry of Patent Cooperation Treaty Patent application no. PCT/CA2019/051206 filed 29 Aug. 2019 entitled A HYBRID ACCOMMODATING INTRA-OCULAR LENS AND METHOD OF USE THEREOF, which claims priority to Canadian patent application No. 3016143 filed 30 Aug. 2018. Both of the foregoing applications are hereby incorporated by reference in their entireties for all purposes. The present invention relates to the applicant's inflatable lens/lens retainer as disclosed in international application publication no. WO 2009/021327 entitled INFLATABLE INTRA-OCULAR LENS/LENS RETAINER published Feb. 19, 2009, as well as international application publication no. WO 2014/021391 published Aug. 14, 2014 entitled EXPANDABLE SUSPENSION SYSTEMS FOR INTRA-OCULAR LENSES and international application publication no. WO 2009/021326 entitled PNEUMATIC INTRA-OCULAR LENS published Feb. 19, 2009.

TECHNICAL FIELD

The invention relates to intra-ocular lenses that can change curvature in response to tension exerted by the ciliary muscle/zonule/lens capsule complex upon the natural lens space within the eye.

BACKGROUND

Intra-ocular lenses that have an ability to re-engage the natural kinetics of the ciliary muscle/suspensory ligament/lens capsule complex after lens extraction, allowing the presbyopic eye to recover its ability to shift focus from distance to near, have emerged. Within this competitive field, much attention has focused upon an ability to insert these new lens types through small corneal incisions within the eye.

Presently, liquid-filled intra-ocular lenses, such as the investigational device manufactured by Power Vision Corporation called the Fluid Lens™, exhibit a variety of limitations. Liquid lodged inside these lens types is compressed and transferred to various regions of the device during the daily routine of the eye shifting focus from near to distance. This repetitive action leaves the sealed edges that hold the device together vulnerable to rupture over time. This proclivity is heightened by the tendency of the liquid to erode and weaken the adhesive bonds holding the sealed edges of the device together. Further to this, liquid-filled intra-ocular lenses tend to be bulky and cumbersome to insert, leaving them particularly prone to damage during the insertion process, which entails that they be compressed and shunted through a narrow tubule before being released into the natural lens space within the eye.

Air-filled intra-ocular lenses are thinner than fluid-filled intra-ocular lenses, and as a result are generally easier to insert. They have no liquid to interfere with the integrity of adhesive bonds holding their structural components together; however, they are inherently plagued by internal reflection and glare. In addition to this annoyance, their refractive properties can be potentially altered by even small changes of barometric pressure. In light of the limitations confronting today's accommodating intra-ocular lens design options, there is need for improvement.

The foregoing examples of the related art are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.

SUMMARY

The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.

According to one embodiment, a hybrid intra-ocular lens is provided which includes both solid optical elements and fluid-filled optical elements, such as air filled and which converts from a solid optical element to a partially liquid or air-filled optical element during accommodation. According to one embodiment a partially air-filled intra-ocular lens comprises a hollow air-filled lens compartment encased on one side by a relatively non-deformable optical element which is met at its convex apex by a second optical element that is relatively deformable. The shape profile of the surface of the deformable optical element that contacts the apex of the non-deformable optical element can be of various configurations: flat, convex, concave, multi-focal or aspherical, provided that an air space resides between the remaining portions of the optical elements when the device is in its habitual resting state. The haptics of the two optical elements converge to connect with each other and are bonded together around their perimeters, thereby defining the size and shape of a hollow, air-filled compartment. Just as it is with the two optical elements, the air-filled compartment thereby comprises an optical region and a haptic region.

When the peripheral regions of the optical regions of the two optical elements are pressed together by opposing external force, the deformable optical element bends to conform to the shape of the non-deformable optical element. During this process, the air which normally occupies the space between the two optical regions is displaced outwardly toward the air space between the haptics. When sufficient opposing force is delivered to the optical regions of the two optical elements, their inner surfaces align and connect, with the ability to subsequently separate without adhesion. At this moment, two aspects of the invention are achieved. Firstly, the optical region of the lens pair no longer has an air interface to create internal reflection and glare. Secondly, the eye can remain focused upon distant objects without being influenced by changes of barometric pressure. This process can be achieved with one or both optical elements having deformable properties.

Radial slots may be provided in the lower surface of the deformable optical element surrounding the perimeter of the optical region of the deformable optical element, connected to a circumferential channel in the deformable optical element, to allow air to circulate freely between the optical region and the haptic region of the air-filled compartment. This channel and network of radial slots is an optional feature of the design, which also provides a means for controlling material distortions that can occur when a spherical shell is forced to alter its shape. The width of the radial slots can be selected to alter the flow of air as required.

More particularly, according to one embodiment there is provided a partially air-filled intra-ocular lens comprising a first non-deformable optical element which is sealed around its perimeter to a second deformable optical element forming a sealed air-filled collapsible cavity, the first non-deformable optical element and the second deformable optical element each having central optical regions and first and second haptic regions associated with respective ones of the first non-deformable optical element and the second deformable optical element and each sealingly connected to the other to form the sealed perimeter. The first optical element has a convex shape upon its inner surface with the apex of the convex inner surface pressing against the central region of the deformable optical element leaving a sealed collapsible air space in the remaining area between the optical regions of the first and second optical elements.

According to a further aspect the sealed air-filled collapsible cavity may comprise an optical region, located between the optical regions of the first and second optical elements, and a haptic region located between the optical region and the sealed perimeter of the haptic regions, wherein the air-filled collapsible cavity has at least one opening communicating between the optical region and the haptic region whereby when external force generated by ciliary muscle tension is directed upon the perimeter of the optical regions of the optical elements, the optical region of the air-filled cavity is compressed, thereby evacuating the air within it toward the haptic region of the air-filled cavity through the communicating channels and the optical surfaces of the first and second optical elements, which are thereby compressed against one another, thereby focusing the eye upon distant objects, and whereby the elasticity of the deformable optical element causes the compression to be reduced when the ciliary muscle tension is reduced. According to a further aspect the at least one opening communicating between the optical region and the haptic region may comprise a circular channel interconnecting with a plurality of radial channels.

According to a further aspect a method of providing an accommodating intra-ocular lens for replacement in the lens capsule of an eye is provided by providing a lens having the foregoing features in combination with an intra-ocular structure for transferring the ciliary muscle tension to the lens.

With this present optical configuration, the only moment whereby this lens design is subject to internal reflection and glare is when air enters back into the space between the two optical elements. This glare potential can be reduced when the internal optical surfaces of the two optical elements are constructed with relatively short radii of curvature. It can be further reduced by optical elements oriented within the eye such that the non-deformable optical element is positioned anterior to the deformable optical element.

In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions. While air is described as the gas contained in the compartment of the hybrid lens, other transparent gases or liquids, referred to collectively as fluids, could be substituted with resulting variation in the refractive indices.

