Extending the range of vision using diffractive intraocular lens technology.

PURPOSE: To describe and to experimentally assess a new intraocular lens (IOL) design using new diffractive technology.

SETTING: AMO Groningen b.v., Groningen, Netherlands.

DESIGN: Experimental study.

MATERIALS AND METHODS: The basic principles of the new diffractive technology are described. The new IOL comprises two diffractive technologies; one is designed to extend the range of vision by elongating the focus, and the other increases the retinal image contrast by correcting chromatic aberration. To assess the potential visual performance, simulations were carried out in clinically verified eye models to predict the clinical defocus curves (visual acuity). The optical performance of the new lens design was evaluated by optical measurements in a model eye. The model eye had a cornea having the spherical aberration and chromatic aberration of an average cataract patient. The measurements were performed in white light and monochromatic light.

RESULTS: The simulations suggested an increase in visual acuity of 0.27 logMAR as compared to an aspherical monofocal IOL in the range from -1 to -3 diopter defocus. The white light modulation transfer function in the far focus was identical to that of a monofocal IOL. The new lens demonstrated negative chromatic aberration, therefore showing the capability to actively reduce ocular chromatic aberration. The experiments also show retinal image characteristics of an extended light source that suggest that dysphotopsias (halos) of the new IOL are comparable to those associated with monofocal IOLs.

CONCLUSIONS: The application of new IOL diffractive technology enabled optical characteristics that suggested that an extended range of vision can be obtained without compromising distance vision.

FINANCIAL DISCLOSURE: All authors are employees of Abbott Medical Optics, Inc.