ReSTOR®, Crystalens™, Tecnis® Multifocal & ReZoom™
Lens Replacement Surgery for Cataracts and Vision Correction
Reviewed by Leslie Doctor, M.D.
For the vast majority of patients wishing to minimize or eliminate their dependence on glasses or contact lenses, LASIK or Custom Wavefront LASIK will be the procedures of choice. If you are not a candidate for LASIK because you have certain LASIK contraindications, often PRK, LASEK or Epi LASIK are recommended by the LASIK surgeon. All of these Laser Eye Surgery procedures are performed by reshaping the cornea by using an Excimer Laser. These procedures are safe, effective and predictable in correcting nearsightedness, farsightedness and astigmatism. However, for patients in their 40's, corneal laser eye surgery may not be able to completely help them overcome their goal of eliminating glasses or contact lenses for arms length or near reading vision as this is the time when people begin to experience presbyopia. In the early phases of presbyopia, your LASIK surgeon may be able to offer you some intermediate and near vision correction through the use of monovision LASIK. With the continual progression of presbyopia, it becomes more and more difficult for patients to maintain their focusing ability for intermediate and near vision due to the gradual loss of accommodation. Presbyopia begins because of the natural loss of elasticity of the crystalline lens inside your eye. Thus, presbyopia is a problem of the lens, not the cornea, and therefore it is the lens that must be treated if someone truly suffers from presbyopia.
About Cataracts, Presbyopia & Lens Implants
Presbyopia also affects just about everyone who has cataracts. In the past, patients undergoing cataract surgery needed to wear eyeglasses, bifocals or reading glasses after cataract surgery in order to see things at intermediate distances or near distances. Lens Replacement Surgery with presbyopia near vision correcting lens implants such as ReSTOR®, ReZoom™, Tecnis® and Crystalens® can also offer cataract patients the opportunity to be less dependent or even free of eyeglasses, readers or bifocals after cataract surgery. Cataract surgery with presbyopia correcting lens implants allows most patients who have had their cataracts removed the flexibility of having clear vision for far away tasks such as driving and watching television, as well as for being able to read the newspaper, medicine bottles and their mail-without depending on glasses. This flexibility provides not just a solution to eliminating glasses, but a functional convenience that allows cataract patients to conduct their daily living activities in an unencumbered manner.
For some patients then, rather than having a corneal laser eye surgery procedure such as LASIK, Custom LASIK, PRK, LASIK, Epi LASIK or monovision LASIK, a different type of refractive surgery can be used to better help them achieve their goals of being less dependent on glasses or contact lenses for not only distance vision, but intermediate arms length and close near vision. This type of refractive surgery is called Lens Replacement Surgery which includes ReSTOR®, ReZoom™, Tecnis® and Crystalens®.
ReSTOR®, ReZoom™ & Crystalens™ Lens Replacement Surgery is performed in a similar manner to cataract surgery. It is performed in an outpatient surgery center. With ReSTOR®, ReZoom™ & Crystalens™ Lens Replacement Surgery, your surgeon will numb the eye with eye drops much like with LASIK. He or she will then make a very tiny incision at the outer edge of the cornea through which a microscopic instrument can be inserted. Using ultrasound from the tip of the microscopic instrument, your surgeon will actually be able to gently break the crystalline lens into pieces small enough to be washed away and drawn through the probe and removed from the eye. Once your natural crystalline lens has been removed, it can now be replaced by a new permanent Intraocular Lens Implant. The new lens is readily inserted and placed in position through the same tiny incision at the outer edge of the cornea through which the natural lens was removed.
In order to help you achieve your goal of being able to see at far, intermediate arms length and up close for reading vision, your surgeon will select from advanced intraocular lens technology available today which includes ReSTOR®, ReZoom™, Tecnis® and Crystalens®. Each of these advanced technology implantable lenses uses a slightly different optical design to help you achieve your goal of clear vision at all distances. Your surgeon and his or her staff will discuss their recommendation based on many factors in your consultation.
ReSTOR® is actually known by the technical name, AcrySof® ReSTOR® Apodized Diffractive IOL.
What is ReSTOR ®?
The AcrySof ReSTOR® Apodized Diffractive Optic Posterior Intraocular Lens is a permanent artificial lens. The ReSTOR® lens is convex on both sides and made of a soft plastic. It is folded and inserted into the eye through a tiny incision smaller than the optic diameter of the lens. After insertion, the lens gently unfolds to ReSTOR® vision. The supporting arms of the lens maintain proper positioning within the eye.
How does it work?
The AcrySof ReSTOR® Intraocular Lens replaces the natural lens. It has a patented optic design using apodization, diffraction and refraction technologies. The apodized diffractive optic design gives it the ability to focus light correctly on the retina for images at various distances without mechanical movement of the lens.
Apodization is a gradual reduction or blending of the diffractive step heights.
This unique technology optimally manages light energy delivered to the retina because it distributes the appropriate amount of light to near and distant focal points, regardless of the lighting situation.
Apodized diffractive optics are designed to improve image quality while minimizing visual disturbances. The result is an increased range of quality vision that delivers a high level of spectacle freedom.
When is ReSTOR® used?
The AcrySof ReSTOR® Intraocular Lens is used in adult patients with and without presbyopia, who desire near, intermediate and distance vision with increased independence from glasses and contact lenses. It is FDA approved for use after cataract surgery.
What will ReSTOR® be able to accomplish?
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.
When should ReSTOR® not be used?
There are no known contraindications. However, based on the FDA clinical trials, Alcon, the lens manufacturer, has indicated the following types of patients possibly should not have the AcrySof ReSTOR ® Apodized Diffractive Intraocular Lens:
Patients that are hypercritical with unrealistic expectations
Patients with excessive complaints about their prescription
Patients who drive at night for a living or whose occupation or hobbies depend on good night vision
Patients who are amateur or commercial airline pilots
Patients who have life long complaints about glare
Patients who are happy wearing glasses
Patients who want guarantees on surgical outcomes
Who is a good candidate for the ReSTOR® Intraocular Lens?
Virtually everyone who has cataracts and is in good general health may be candidate for implant surgery, but people with chronic infections, uncontrolled diabetes, or other health problems may have to wait until these conditions are under control prior to surgery.
People who have had prior laser eye surgery including LASIK, Custom LASIK, PRK, LASEK, Epi LASIK or any other corneal Laser Eye Surgery may be acceptable candidates for ReSTOR® implantation as long as their eyes are in good health. After a thorough examination and consultation, your surgeon will be able to better advise you if you qualify for the ReSTOR ® implant.
Crystalens™, is a single-focus accommodating intraocular lens. It was developed to address the loss of intermediate and near focusing ability. Crystalens™ is manufactured from a proprietary and specially formulated solid silicone called Biosil™. Crystalens™ is a cataract replacement lens that works naturally with your eyes' muscles to give you the quality of vision you enjoyed when you were younger.
The revolutionary design element that makes Crystalens™ the state-of-the-art replacement lens are "hinges" which are designed to allow the lens to move, or accommodate to focus on objects near, far and all distances in-between seamlessly.
Unlike old-style fixed focal lenses, which didn't move, Crystalens™ has the ability to move, thus focusing as your eye's natural lens did when you were younger. Your surgeon will take precise measurements to insure the correct lens power selection for your eye.
Upon having your cataract removed, it is now possible for your surgeon to replace the lens with Crystalens™ in order to help you regain the ability to see not only at distance, but also see intermediate and near objects-without dependence on glasses.
After your surgery and the placement of Crystalens™, you will "relearn" how to focus your vision with your doctor's help and instruction. After a brief time of adaptation, it is expected that you will be able to perform most tasks-far, intermediate and near-without dependence on glasses.
On June 26,2008 the U.S. Food and Drug Administration (FDA) approved the fourth generation Crystalens™ called the Crystalens HD™. The Crystalens HD™ is the latest generation of the only FDA approved accommodating lens and offers improvement in near vision for many patients along with its well proven improvement in intermediate vision.. The first generation Crystalens ™ accommodating intraocular lens (IOL) was approved by the FDA in November 2003.
ReZoom™ Multifocal Intraocular Lens
The ReZoom™ Multifocal Intraocular Lens is an option for the treatment of both cataracts and presbyopia. It is designed to provide patients multifunctional vision if they have a strong desire for greater independence from glasses or contacts. The ReZoom™ Multifocal Lens has a patented lens design called Balanced View Optics™ Technology. This lens design creates multiple focal points so patients can see well at a variety of distances, be it near, mid-distance, or far.
The ReZoom™ Multifocal Lens has carefully proportioned visual zones that provide it with the ability to provide patients with vision at varying distances. Each ReZoom™ Multifocal Lens is divided into five different zones with each zone designed for different light and focal distances. Unlike other earlier multifocal lens designs, the ReZoom™ Multifocal Lens has proportioned the size of its zones to provide for good vision in a range of light conditions. For instance, some zones have been designed to offer greater low light-distance vision during night driving whereas others provide better bright light-near vision for close vision activities.
If you have been diagnosed as having cataracts and are experiencing one or more of the following vision problems, you may be a candidate for the ReZoom™ Multifocal lens:
Difficulty seeing close objects
Difficulty seeing to drive, especially at night
Changing glasses prescriptions
Common Questions About the ReZoom™ Multifocal Intraocular Lens
Will I still need to wear glasses if my surgeon recommends a ReZoom™ Multifocal lens?
The results will vary depending upon your vision, lifestyle and the anatomy of your eyes. Most people find that they need glasses to read small type or drive at night. Most people, however, can go to the store or conduct many of their day's activities without depending on glasses.
How is the ReZoom™ Multifocal Lens different from traditional single-vision intraocular lenses?
The ReZoom™ IOL is a multifocal intraocular lens. Unlike traditional single-vision lens implants, the ReZoom™ Multifocal lens provides quality vision both at a distance and up close. Traditional single-vision lenses usually provide good vision only at a distance with limited ability to see objects that are near without glasses.
How does the ReZoom™ Multifocal lens replace the cataract?
The natural lens inside the eye is gently removed through a small micro-incision in the periphery of your eye's cornea. The cataract-impaired lens is then removed through this incision and the lens implant is inserted in its place to permanently replace it. The procedure usually takes about 15 to 45 minutes and vision is usually improved immediately.
How long after surgery until I see my best?
Like most procedures, this depends upon the overall health of your eye. For most people, vision is noticeably better immediately and continues to improve during the first few weeks after the procedure.
Does the ReZoom™ Multifocal lens require an adjustment period?
Yes. For most people there is a period of weeks when your brain is learning to "see" up close and at a distance with the new lens. This adjustment period is usually complete within 6 to 12 weeks. Also, like all multifocal lenses, some people report halos or glare around lights. Again, for most people this diminishes over time. For some, it becomes less troublesome but never completely goes away. Most people report that the ability to see near and far outweighs any visual side effects associated with the lens.
Are there any risks of having the ReZoom™ Multifocal lens procedure?
Yes. With any surgical procedure there are risks. The biggest risk with any cataract procedure is infection. Less than one percent of patients having a lens implant procedure ever get an infection and most are treated successfully with medications. Infections, however, can cause a severe or total loss of vision.
Tecnis® Multifocal Intraocular Lens Implant
The Tecnis® Multifocal Intraocular Lens Implants is an, ultraviolet light-absorbing posterior chamber artificial lens for implantation in the eye to restore vision after a clouded natural lens or Cataract is removed. It is made of a silicone material that is foldable so that it can be inserted into the eye through a very small incision that is actually smaller than the diameter of the lens itself.
The Tecnis® Multifocal IOL is based on an aspheric optical design which was engineered to reduce the spherical aberration of an average cornea. The Tecnis® Multifocal IOL is based on a principle of diffraction—as is the AcrySof®ReSTOR® IOL with the Tecnis® Multifocal IOL having its diffractive rings on its back surface of the lens. The rings start very close to the center of the lens and then continue out toward the periphery, usually with an increasing distance between the rings. As a result, the lens achieves its multifocal effects with minimal dependence on the size of the pupil so that even in the presence of relatively small pupils, the Tecnis® Multifocal can provide excellent near vision.
The Tecnis® Multifocal IOL has been shown in a clinical study to provide good near, intermediate and distance vision and thereby reduce eyeglass dependence in patients who have undergone cataract surgery.
Whether you are considering LASIK, Custom LASIK or any type of Laser Eye Surgery, the ultimate decision as to which type of surgery-corneal Laser Eye Surgery or ReSTOR®, Crystalens™ or ReZoom™ Lens Replacement Surgery-is best for you, can only be made after a thorough examination and consultation.