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Accommodative intraocular lenses: current status.

Abstract

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.

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BibTeXRIS

H Burkhard Dick. 2005. Accommodative intraocular lenses: current status.. https://doi.org/10.1097/00055735-200502000-00004

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Synchrony dual-optic accommodating intraocular lens. Part 2: pilot clinical evaluation.

PURPOSE: To evaluate the clinical outcomes of an accommodating dual-optic intraocular lens (IOL). SETTING: Private practice and university centers. METHODS: A prospective noncomparative case series with retrospective control comprised 21 patients (26 eyes) scheduled for small-incision extracapsular cataract extraction by phacoemulsification with implantation of the Synchrony dual-optic accommodating IOL (Visiogen) (accommodating IOL group) and 10 patients who had small-incision extracapsular phacoemulsification with implantation of a monofocal, single-optic IOL at least 6 months previously (control group). Patients were examined 1, 3, 6, and 12 months after surgery. Defocus curves in the accommodating IOL group were compared with those in the control group. The main outcome measures were postoperative distance uncorrected and best corrected visual acuity; near uncorrected, distance corrected, and near corrected visual acuity; and accommodative range based on defocus curves. RESULTS: Twenty-four eyes were available at the 6-month follow-up visit. All eyes had best corrected distance visual acuity of 20/40 or better, and 19 eyes (79%) had an uncorrected distance visual acuity of 20/40 or better. Uncorrected near visual acuity was 20/40 or better in all eyes. With distance correction, 23 eyes (96%) had an acuity of 20/40 or better at near. Defocus curve analysis suggested a mean accommodative range of 3.22 diopters (D) +/- 0.88 (SD) (range 1.00 to 5.00 D) in the accommodating IOL group and 1.65 +/- 0.58 D in the control group (range 1.00 to 2.50 D) (P<.05). CONCLUSION: The Synchrony dual-optic IOL shows promise as an option to provide accommodative function in pseudophakic patients.

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