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3930 Hoyt Avenue
Everett, WA 98201
ph 425.259.2020
fax 425.259.2801
www.lasikdrs.com
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Traditional Lens Implants
Traditional lens implants are “single focus” lenses, which are generally selected for distance vision. They may be made of a highly polished and very stable plastic material called PMMA (polymethyl methacrylate), or of silicone or flexible acrylic material that allows folding of the lens and placement through a smaller incision. They are made with a central optic (lens) and two opposing flexible spring-like haptics, which press against the sides of the lens capsule to keep the implant centered in the eye.
These lenses are usually fully covered by Medicare and private insurers. Some “new technology” traditional lenses such as the Tecnis Z-9000 (AMO, Inc.), the AcrySof SN60WF (Alcon ) and the SofPort AO (Bausch & Lomb) have special aspheric designs, which may provide better focus under conditions such as fog, rain, or dim light. All of these lenses typically provide excellent distance vision, but most people who have these lenses need reading glasses for near vision. All of these lenses have a tried and proven design and are the type most commonly used for modern cataract surgery.
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Presbyopia-Correcting Lens Implants
New lens implants that provide enhanced near vision, in addition to good distance vision, have recently been developed. These new lens implants may eliminate or greatly reduce dependence on reading glasses after cataract surgery. They correct near vision by either a multifocal design or by an accommodative design. Multifocal lenses include the AcrySof ® ReSTOR® by Alcon and the ReZoom ™ by AMO. These lenses are designed with diffractive concentric rings of lenslets, or optical zones, which alternate between near and far focus and are placed on the surface of the lens implant. Typically, 80% to 90% of people who have these lenses in both eyes are free of the need for glasses for any range of vision. This expanded range of focus comes at a cost; the brain must learn to screen out a foggy secondary image through a process called neuroadaption. Still, the vast majority of patients who have these lenses in both eyes are ecstatic with their vision and freedom.
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The Crystalens® implant by Bausch & Lomb is the first lens implant approved by the FDA that provides near vision by accommodation, using the natural near focus system of the eye. This implant has a smooth, single-focus lens supported with hinges, which allow the lens to shift in position in response to focusing effort. This approach provides a seamless, full range of vision and avoids some of the issues associated with multifocal design, which may include reduced contrast vision and halos around light sources at night. In 2003, Dr. Lueth became the first practicing ophthalmologist to have the Crystalens® implants placed in his own eyes when he underwent lens surgery at age 49.
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These new lenses are more expensive than a traditional lens and the added near function is considered a refractive benefit, which is not covered by Medicare and most private insurances. These additional charges are usually an out-of-pocket expense. Treatments for astigmatism and refinement of the distance vision by laser PRK are usually included with these lenses if needed.
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