AcrySof® IQ® Intraocular Lens (IOL)

The Natural Crystalline Lens

The crystalline lens is a refractive structure within the eye consisting of a transparent membrane filled with a transparent protein. The crystalline lens is responsible for approximately 40% of the eye's focusing power and can change its curvature in order to focus images of nearby objects in our environment. As part of the normal aging process, the crystalline lens progressively loses its clarity and elasticity. This hardening of the natural lens begins very early in life, but tends not to interfere with clear near vision until after the age of 40. At this approximate age, when the lens tissue has hardened and lost its ability to change its curvature sufficiently enough to focus for reading vision, the condition is called presbyopia. When presbyopia occurs, individuals require reading spectacles to fine-tune vision for near tasks such as reading or sewing.

Another aging process that occurs within the natural lens is the progressive loss of transparency in the transparent protein. When the lens opacity begins to impair an individual's functional vision or block vision, we describe the condition as cataract, which can be surgically extracted. However, once the lens tissue is removed, spectacles, contact lenses or an intraocular lens (IOL) implant must replace the lost optical power of the natural lens to achieve visual correction. Today, ophthalmologists use the intraocular lens device as the most typical method of restoring optical power after natural lens extraction. NOTE: Cataracts may also develop as the result of exposure to ultraviolet (UV) rays, eye trauma, medications, disease, genetics or infection prior to birth. 

Restoring Optical Power & the AcrySof IQ Intraocular Lens

Considering the importance of an IOL's refractive properties, Gimbel Eye Centre uses the AcrySof IQ IOL, a design proven to give most patients the best potential for quality vision. By analyzing human corneal curvature characteristics, Alcon Laboratories has developed the AcrySof IQ to reduce image distortion caused by the cornea. Without increasing the IOL's edge thickness, the AcrySof IQ has an improved aspheric curvature that brings light rays to a single, ideal focal point.

In addition to its refractive role, the crystalline lens is also responsible for filtering UV radiation and high-energy blue light. Fortunately, when the natural lens tissue yellows, the yellow tint actually protects the macula (i.e., the portion of the retina responsible for detailed central vision) by filtering the near UV blue light transmitted within the sun's rays and artificial light. When the lens tissue is removed during lens extraction surgery, the eye loses this yellow lens tint and becomes vulnerable to the effects of UV and near UV blue light exposure. It may be more difficult for the eye to handle these wavelengths as we get older - when circulation is less efficient. Some researchers believe that while some of the blue light at the beginning of the visible range of the light spectrum contributes to color perception, near UV blue light may be harmful to the macula and may contribute to macular degeneration and loss of vision. 

Until now, the most commonly manufactured IOL implants were lenses that filter UV radiation only. This means, after lens extraction and implantation of a traditional IOL that absorbs UV rays only, a patient is still vulnerable to the transmission of near UV blue light in the environment. Applying the principle of yellow tinting as an effective near UV blue light filter as well as advances in optical design technology, Alcon Laboratories has developed the AcrySof IQ IOL to provide individuals with maximized visual acuity as well as protection from UV and near UV blue light after natural lens extraction. NOTE: The AcrySof IQ IOL provides the same monofocal refractive correction as provided by a traditional monofocal IOL, offering a fixed-range of focus only. This means, after lens extraction and implantation of the AcrySof IQ IOL (a monofocal lens), a patient is reliant upon spectacles to fine-tune some ranges of focus (i.e., near, intermediate and/or distance vision) - depending on patient prescription, preference, healing, etc. NOTE: Monofocal refers to a single focal point for light as compared to two focal points (i.e., bifocal) or a spreading out of the focal point (i.e., multifocal).

Basic Information About the AcrySof IQ Intraocular Lens

• The patented yellow color of the AcrySof IQ IOL is biocompatible due to its electrically bonded structure (i.e., covalently bound structure).

• At this time, the AcrySof IQ IOL cannot correct astigmatism.

• The yellow tinting of the AcrySof IQ intraocular lens, approximates the natural discoloration (i.e., natural yellowing) of a healthy adult crystalline lens; therefore, there is no significant negative impact on color perception, contrast sensitivity or night driving after implantation of the yellow-tinted AcrySof IQ IOL.

• The AcrySof IQ is compatible with secondary cataract treatment (i.e., Nd: YAG laser treatment), if required.

• The long-term effects of filtering blue light and the clinical efficacy of that filtering on the retina have not been conclusively established.

For further information, please do not hesitate to contact a Gimbel Eye Centre representative.