Design and fabrication of accommodating fluidic intraocular lens
accommodating intraocular lens (IOL) is designed to restore the vision of youth to the middle aged or elderly individuals affected by presbyopia and/or cataracts.Our mission is to provide a fluid based lens technology that solves clinical and lifestyle needs caused by these conditions thereby creating the most significant innovation in vision correction surgery since the invention of the IOL. The ciliary muscles that support the lens and capsule therefore are believed to act in a sphincter muscular mode. Within the eye, however, the capsule is connected around its circumference by approximately 70 tiny ligament fibers to the ciliary muscles, which in turn are attached to an inner surface of the eyeball. About 97 percent of cataract surgery patients receive intraocular lens implants, with the annual costs for cataract surgery and associated care in the United States being upwards of billion. In the United States, about 2.5 million cataract surgical procedures are performed annually, making it the most common surgery for Americans over the age of 65.
The crystalline lens, which is situated posterior of the pupil in a transparent elastic capsule supported by the ciliary muscles, provides about 15 diopters of power, and also performs the critical function of focusing images upon the retina. Isolated from the eye, the relaxed capsule and lens take on a spherical shape. Because the lens itself is composed of viscous, gelatinous transparent fibers, arranged in an “onion-like” layered structure, forces applied to the capsule by the ciliary muscles cause the lens to change shape.An accommodating intraocular lens is provided in which a deflectable lens element is anchored to a substrate along its optical axis to define a fluid filled space. IOLs are generally single element lenses made from a suitable polymer material, such as acrylics or silicones. It still further would be desirable to provide methods and apparatus that utilize pressure applied by the accommodating muscular action to deform an optical surface of the IOL.Fluid-filled haptics disposed in fluid communication with the space vary the fluid volume in the space responsive to forces applied by the ciliary muscles, thereby causing the periphery of the lens element to deflect relative to the substrate and changing the optical power of the intraocular optic comprising a flexible anterior element, a posterior element, an optical axis, the flexible anterior element is the most anterior aspect of the accommodating intraocular lens along the optical axis, the flexible anterior element and the posterior element at least partially defining an optic fluid chamber disposed between the flexible anterior element and the posterior element;a haptic portion peripheral to the optic and configured to deform in responsive to ciliary muscle movement, the haptic portion comprising at least one haptic fluid chamber in fluid communication with the optic fluid chamber; anda fluid disposed within the optic fluid chamber and the at least one haptic fluid chamber, wherein the fluid is adapted to be moved between the at least one haptic fluid chamber and the optic fluid chamber in response to deformation of the haptic portion, and wherein a periphery of the flexible anterior element is adapted to be displaced more than a portion of the flexible anterior element disposed along the optical axis in response to movement of the fluid. After placement, accommodation is no longer possible, although this ability is typically already lost for persons receiving an IOL. 5,443,506 to Garabet describes an accommodating fluid-filled lens wherein electrical potentials generated by contraction of the ciliary muscles cause changes in the index of refraction of fluid carried within a central optic portion. In particular, it would be desirable to provide an IOL in which muscular pressure may be applied through one or more actuators to obtain a mechanical advantage.