Tecnis® Intraocular Lenses

The Tecnis® intraocular lens is the first intraocular lens based on the wavefront data that makes modern LASIK procedures more accurate than in the past. When your eye's natural crystalline lens is removed during cataract surgery, it is replaced with an artificial lens. The type of intraocular lens used to replace your natural lens will determine what your vision is like after cataract surgery.

Traditional monofocal lenses used to replace your natural lens generally only gave good distance vision. This meant that you could often drive a car without glasses, but close-up vision required reading glasses. The Tecnis® intraocular lens is designed to give you good vision both at a distance and up-close with reasonably functional intermediate vision. This is what is described as giving "improved functional vision." In addition, Tecnis® has been shown in clinical studies to give you better vision for driving and low-light situations compared to monofocal lenses.

How Tecnis® Works

Your eye’s natural lens allows you to see at different distances through a process of accommodation. In this process, the natural lens changes shape to focus on objects at different distances. Tecnis® is not an accommodating lens – like Crystalens® and Synchrony® – it uses a different process to let you see objects at varying distances.

Tecnis® is a multifocal lens, which focuses light from different distances on the retina simultaneously. The light hitting the retina is about one-half from distant objects and one-half from near objects, creating images of different focal clarities. When you want to look at a particular object, the brain picks the clearest image of that object and you see it. It may seem complicated, but your brain does this kind of visual trick all the time. After a short adjustment period, most people have no difficulty sorting out the different images.

The Tecnis® Design

The Tecnis® intraocular lens is designed to do two things: reduce spherical aberrations and give good vision both up-close and at a distance. Ideally, the eye's cornea and lens should be spherical to give the best focus of light on the retina, but most people's eyes have some degree of aberrations from spherical, known as spherical aberrations.

Understanding the significance of spherical aberrations came as a result of wavefront data. Vision is sharpest when spherical aberrations are at their minimum, and wavefront data showed this occurred when patients were at age 19. Wavefront data showed that spherical aberrations increased in the lens as a patient aged, but not in the cornea, which remained stable. The Tecnis® intraocular lens was designed to counteract the spherical aberrations constant in the cornea to give a net spherical aberration of zero.

To give good up-close and distance vision, the Tecnis® lens was designed to focus light onto the cornea from both up close and far away, giving the Tecnis® user clear images from both distances. It does not have vision zones like the ReZoom intraocular lens, so quality of vision is not dependent on the level of light. The mixed-focus approach also allows for Tecnis® users to have reasonable intermediate vision.

Risks of Tecnis® Intraocular Lens

Cataract surgery, whether you select the Tecnis® intraocular lens or any other replacement lens, carries risks. Some of the risks include the possibility of infection or hemorrhage, retinal detachment, and macular edema.

There are two main risks specific to the Tecnis® intraocular lens. First, although most people adjust quickly to multifocal lenses, a small percentage of people never adapt. This may result in visual defects that lead to dizziness, disorientation, and vertigo, among other effects, and some people elect to have the lens removed and replaced with a monofocal lens.

Second, although AMO (the manufacturer of Tecnis®) has won approval from the FDA to claim that Tecnis® improves the user's ability to drive after cataract surgery, this is in comparison with monofocal lenses and not with other multifocal lenses. There is some data to suggest that nighttime visual artifacts like glares and halos may be significant, possibly even worse than other multifocal intraocular lenses.

The only way to decide which intraocular lens is right for you is through a consultation with an ophthalmologist with experience in placing many different intraocular lenses. Please schedule a multifocal IOL consultation with a local doctor today.