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Presbyopia and Presbyopia Correcting Implants

Dr. Khater is proud to offer two different styles of presbyopia correcting implants: ReZoom and ReSTOR.


bulletPresbyopia is a term used to describe the loss of near or reading vision due to changing.
bulletPresbyopia affects nearly every adult over the age of 50.1
bulletPresbyopia is caused in part by a gradual hardening of the natural crystalline lens of the eye. As the lens gets harder and less flexible, the eye�s ability to switch from seeing objects at a distance (driving) to seeing objects that are near (reading) is compromised. (See image at right.)

bulletThe most commonly prescribed treatments for the loss of near or reading vision from presbyopia are reading glasses or bifocals.
bulletToday, depending upon the lifestyle and eye health needs of an individual, a person with cataracts and presbyopia can be treated with a new generation of presbyopia-correcting intraocular lens implants.
bulletOn May 3, 2005, CMS (Centers For Medicare and Medicaid Services) published a ruling that made presbyopia-correcting intraocular lens technology accessible to a broad range of people.

Intraocular Lenses: An Overview

bulletIntraocular lenses (IOLs) are small devices � with an optic usually about 6.0 mm in diameter � that are used to replace the natural crystalline lens of the eye when the lens of the eye becomes clouded due to a cataract and light can no longer pass clearly through the eye to focus on the retina.
bulletApproximately 14 million IOLs are implanted worldwide each year.
bulletPrior to FDA approval of multifocal IOLs that correct for distance, intermediate and/or near vision, IOLs provided correction of vision at one plane � usually distance vision. Patients were required to wear glasses, bifocals or trifocals for intermediate and near vision.
bulletIntraocular lenses are implanted by ophthalmologists, highly trained medical doctors who have completed a four- to five-year residency program following medical school.


The Crystalens accommodating IOL

Crystalens is an accommodating intraocular lens that, unlike a standard IOL, can treat both a person's cataracts and presbyopia�loss of near and intermediate vision. You probably noticed in your forties that you started to lose some of your up-close vision and had to start wearing reading glasses. Crystalens not only treats your cataracts (a clouding or hardening of your lens), but can also reduce or eliminate your dependence on glasses. It does so by recreating accommodation similar to your eye's natural lens. The unique Crystalens can reduce or eliminate glasses for most activities, including: reading a book, working on the computer, and driving a car.

Crystalens was modeled after the human eye. Like the natural lens, it uses the eye muscle to flex and accommodate in order to focus on objects in the environment at all distances. Crystalens dynamically adjusts to your visual needs.

Crystalens is designed to allow the optic, or the central circular part of the lens that you see through, to move back and forth as you constantly change focus on images around you. Crystalens flexes as you focus your vision.

Crystalens is:

bulletThe first and only FDA-approved accommodating intraocular lens
bulletThe only FDA -pproved intraocular lens that uses the natural focusing ability of the eye
bulletThe only FDA-approved presbyopia correcting IOL for cataract patients that provides a single focal point throughout a continuous range of vision

Few patients with Crystalens have experienced problems with glare, halos and night vision. Crystalens focuses only one image to the back of the eye, unlike a multifocal lens that projects multiple images, requiring your brain to �adjust� to the differences.

The effectiveness of Crystalens was proven in clinical trials:

bulletSignificantly more patients implanted with a Crystalens (88.4%) could see better at all distances than patients implanted with a standard IOL (35.9%).
bulletMost patients have continued to report excellent vision 7 years after implantation with Crystalens. More than 100,000 Crystalens implants have been implanted worldwide, and that number is growing daily.

Crystalens accommodates like the natural lens. After implantation of Crystalens, most patients will see brighter and clearer from distance, intermediate to near like they did when they were younger.

ONLY FDA-Approved accommodating IOL

Crystalens was the first presbyopia correcting IOL introduced into the United States market and is currently the only FDA-approved accommodating IOL. Crystalens addresses the limitations of standard monofocal IOLs and multifocal IOLs by providing the following advantages to patients:

bulletProvides a Broad Range of Vision: Crystalens moves and changes shape using the eye's natural focusing mechanism, instead of remaining fixed and stationary within the eye. This movement, or accommodation, allows the eye to focus on objects across a broad range of distances to reduce or eliminate dependence on glasses. In particular, this accommodation provides significant advantages in addressing intermediate vision.
bulletMaintains Clarity of Vision: Unlike multifocal lenses, Crystalens directs all available light received by the eye to a single focal point, comparable to that of a healthy natural lens.
bulletPatient Adjustment Not Required: Crystalens produces a single image consistent with normal vision, meaning patients do not need to neuroadapt to viewing multiple images. Patients also do not need to tolerate or adjust to high levels of halos and glare often associated with multifocal IOLs.


The ReZoom� Multifocal IOL (Lens)

bulletThe ReZoom� Multifocal Lens is implanted in the eye and replaces the cataractous natural crystalline lens of the eye. The lens is normally implanted in both eyes.
bulletThe ReZoom� Multifocal Lens is designed to provide:
- Sharp distance vision (driving, golfing, walking)
- Critical intermediate vision (computer use, cooking, talking face-to-face)
- Crisp near vision (reading)
bullet92% of people receiving the ReZoom� Multifocal Lens technology function independent of glasses in most daily situations (see chart at right).

bulletThe ReZoom� Multifocal Lens, featuring Balanced View Optics� technology (see illustration below), is designed to deliver a full range of vision � near, intermediate and distance.
bulletThe ReZoom� Multifocal Lens is indicated for the correction of cataracts in adult patients with or without presybopia.

For More Information, please see the ReZoom IOL Patient Information Brochure.

The ReSTOR � Apodized Diffractive IOL

Apodization is the gradual tapering of the diffractive steps from the center to the outside edge of a lens to create a smooth transition of light between the distance, intermediate and near focal points. Diffraction involves the bending or spreading of light to multiple focal points as it passes through the lens. On the AcrySof� ReSTOR� IOL, the center of the lens surface consists of an apodized diffractive optic. This means that the series of tiny steps in that center area work together to focus light for near.

The refractive region of the AcrySof� ReSTOR� IOL bends light as it passes through the lens to a focal point on the retina. This outer ring of the AcrySof� ReSTOR� IOL surrounds the apodized diffractive region and is dedicated to focusing light for distance vision.

The AcrySof ReSTOR � Intraocular Lens has been shown in a clinical study to provide good near, intermediate and distance vision with increased independence from glasses.


For More Information, please see the ReSTOR IOL Patient Information Brochure.



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West Texas Eye Associates
Tim Khater, M.D., Ph.D.

Lubbock's Eyecare Center for Excellence

Copyright 1999 Tim Khater, M.D., Ph.D..  For information, please contact drkhater@wtxeye.com

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Last updated January 11, 2009 .
This page designed and created by Tim Khater, M.D., Ph.D..  (yes, the doctor really created the web page, ...without any help from his kids...)

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