An lens for correcting human vision, for example an IOL, contact lens or corneal inlay or onlay, that carries and interior phase or layer comprising a pattern of individual transparent adaptive displacement structures. In the exemplary embodiments, the displacement structures are actuated by shape change polymer that adjusts a shape or other parameter in response to applied energy that in turn displaces a fluid media within the lens that actuates a flexible lens surface. The adaptive optic means of the invention can be used to create highly localized surface corrections in the lens to correct higher order aberrations-which types of surfaces cannot be fabricated into and IOL and then implanted. The system of displacement structures also can provide spherical corrections in the lens.

Adaptive optic lens and method of making

Cataract is a significant cause of visual disability in the pediatric population worldwide and can significantly impact the neurobiological development of a child. Early diagnosis and prompt surgical intervention is critical to prevent irreversible amblyopia. Thorough ocular evaluation, including the onset, duration, and morphology of a cataract, is essential to determine the timing for surgical intervention. Detailed assessment of the general health of the child, preferably in conjunction with a pediatrician, is helpful to rule out any associated systemic condition. Although pediatric cataracts have a diverse etiology, with the majority being idiopathic, genetic counseling and molecular testing should be undertaken with the help of a genetic counselor and/or geneticist in cases of hereditary cataracts. Advancement in surgical techniques and methods of optical rehabilitation has substantially improved the functional and anatomic outcomes of pediatric cataract surgeries in recent years. However, the phenomenon of refractive growth and the process of emmetropization have continued to puzzle pediatric ophthalmologists and highlight the need for future prospective studies. Posterior capsule opacification and secondary glaucoma are still the major postoperative complications necessitating long-term surveillance in children undergoing cataract surgery early in life. Successful management of pediatric cataracts depends on individualized care and experienced teamwork. We reviewed the etiology, preoperative evaluation including biometry, choice of intraocular lens, surgical techniques, and recent developments in the field of childhood cataract.

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Pediatric cataract: challenges and future directions

Purpose of review The possibility of using a monofocal IOL with accommodative ability allows refractive cataract surgery with a clearly decreased potential of photic phenomena. Three IOLs of different designs and materials have demonstrated accommodative ability, but the degree of accommodative amplitude has been reported to different extents and variabilities. The plate-haptic CrystaLens has a hinged design that might permit forward movement of the optic as a result of pressure changes in the vitreous cavity. The 1CU has modified haptics that bend in the bag as the lens capsule contracts, which are supposed to cause anterior displacement of the lens optic. With the dual-optic one-piece Synchrony, springlike haptics separate a high-plus anterior lens from a posterior minus lens. With accommodative effort, the capsular bag expands and the springs express kinetic energy, which might allow the optics to separate as the anterior lens moves forward. Recent findings This article seeks to clarify and distinguish the concepts of true accommodation and pseudo accommodation. Current designs of accommodative IOLs are supposed to work by the focus-shift principle to allow true pseudophakic accommodation. Studies that biometrically assessed optic shift found no or only low amplitudes of forward movement. The amount of forward movement, if present, was highly variable between patients. To date, most studies present psychophysical data for the proof of concept, which alone seems insufficient. Capsule bag performance and posterior capsule opacification with accommodative IOLs seem worse than those with standard intraocular lenses. Summary The potential clinical benefits of accommodative IOL technology for both cataract patients and refractive patients may place accommodative IOLs in a competitive position with multifocal IOL technology.

Accommodative intraocular lenses: current status.

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. 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 lens.

Accommodating intraocular lens having peripherally actuated deflectable surface and method

Purpose of review To discuss current designs, indications, contraindications and controversies pertaining to capsular tension devices. Recent findings Capsular tension rings and other newer endocapsular support devices have become increasingly important in the management of zonular weakness during cataract extraction. They have been found to improve both intraoperative support during phacoemulsification and postoperative intraocular lens centration. Since the introduction of the original capsular tension rings in 1991, there has been a progressive evolution of this device to help deal with profound zonular weakness. These newer devices, which permit scleral-suture fixation, include the modified capsular tension ring and the capsular tension segment. Summary Continual advances in capsular tension device technology have allowed for increased safety and efficacy in performing cataract surgery in patients with zonular weakness with newer devices being evolved to manage more profound cases.

Capsular tension rings and related devices: current concepts.

Purpose: To evaluate the extent of capsular bag shrinkage after cataract surgery with intraocular lens (IOL) implantation and develop a regression formula to predict postoperative capsular bag size.

Setting: Eye Hospital, Johannes Gutenberg-University, Mainz, Germany.

Methods: The axial length (AL), anterior chamber depth, and corneal radius in 58 eyes were measured preoperatively. Cataract surgery was by phacoemulsification followed by implantation of a 3-piece, acrylic, posterior chamber IOL. The capsular bag diameter and anterior capsulorhexis were measured intraoperatively and 1 day and 1, 3, and 6 months postoperatively using a Koch capsule measuring ring (HumanOptics).

Results: The mean capsular bag size was 10.53 mm intraoperatively, 10.31 mm at 1 day, 9.62 mm at 1 month, 9.07 mm at 3 months, and 9.01 mm at 6 months. The mean capsular bag shrinkage over the entire postoperative period was 14.8% (P<.001). Of the parameters studied, only AL had a positive correlation with capsule shrinkage. The correlation was moderate but statistically significant (P = .001).

Conclusions: A correlation was found between capsular bag shrinkage and AL. Using preoperative biometric data, a regression formula of moderate validity was determined to predict capsular bag shrinkage.

Gudrun Pfirrmann

Papers

Capsule measuring ring to predict capsular bag diameter and follow its course after foldable intraocular lens implantation