How Do I Know Which Lens to Choose?
When your cataract is removed, a new lens is placed inside of your eye. This makes cataract surgery an exciting time because patients who had been nearsighted or farsighted can now be made to have excellent vision without glasses. 20 years ago all patients receive the same type of lens with their cataract surgery. Over the last 10 years, manufacturing companies have developed new lens technologies. These lens options can give you additional benefits, but also more choices that need to be made in determining your lens implant type. Because of these multiple options, lens selection can be a frustrating process. The problem with intraocular lenses inserted with cataract surgery is that there is no way to try them before surgery to see which one you like the best. There are 2 important things to consider when choosing the artificial lens to be used in your cataract surgery: the type of lens and the power of the lens. Choosing a cataract lens depends on many personal factors, including
- What activities do you do during the day and which ones would you like to do without glasses if possible?
- Are you able to pay extra money for a lens that does more than the standard lens covered by your insurance company?
- At what distances would you like to see most clearly without glasses – near (reading), intermediate (computer screen), or far (driving)?
In order to determine the power of the lens implant, a series of eye measurements is performed. These measurements are then used in complex mathematical equations to calculate the power of your new lens. Because of variability in biological systems (not every eye is the same), there can be inaccuracies in the formulas.
There are now many different lens options available to patients. You and Dr. DeBry will work together to determine the perfect lens for you. Currently, the following types of lenses are available…
- Standard lens (monofocal) – This high-quality, clear lens delivers excellent vision at only one distance. The focal point or distance at maximum clarity can be set to distance (driving, golfing, watching TV), intermediate (grocery store shelves, computer, car dashboard), or near (reading, hobbies). There is no extra out-of-pocket cost with a monofocal lens.
- Multifocal lens – Designed to reduce your need for eyeglasses for both distance and near vision, this lens gives you clear vision at several distances. This is a special lens and is not fully covered by insurance so there would be an extra payment for this lens.
- Toric lens – Designed to treat astigmatism and deliver excellent vision at a single distance. This special lens is also not fully covered by insurance.
- Accommodating lens (Crystalens) – Designed with hinges intended to allow this lens to shift its position inside to focus at varying distances.
- Aspheric lens – Designed to improve contrast sensitivity and visual clarity under certain circumstances.
- Monovision – this implant technique uses a monofocal lens with a different power in each eye so that you don’t have to use glasses for most of your daily activities. Your dominant eye is generally set for distance, and the other eye is set for near. Many people successfully use monovision with contact lenses. Successful monovision requires cataract surgery for each eye.
Am I a good candidate for a Multifocal Lens?
With a standard monofocal lens implant, the vision will be very clear in the distance but very blurry up close (for reading) without glasses. Some patients have even complained that they could not see their food at the dinner table without using reading glasses. Multifocal lenses were developed to allow patients to see well at several distances WITHOUT GLASSES after cataract surgery. Multifocal lenses offer benefits above and beyond those of standard lenses. They are not covered by insurance and require an additional out-of-pocket expense. Therefore, it is important to evaluate the following considerations when determining whether a multifocal lens is right for you.
Eye diseases, such as glaucoma, diabetic retinopathy, diabetic macular edema, or macular degeneration, can negatively affect the health of the eyes and the quality of the vision. These diseases, even in the early stages, could cause problems with premium lenses. A multifocal lens is not recommended if you have one of these eye diseases.
Visual needs should also be considered when deciding on a multifocal lens. The technology contained in these lenses that allow you to read without glasses may lead to mild symptoms such as glare, halos, or decreased contrast sensitivity in certain conditions, such as night driving or dim restaurant lighting. Some patients rarely notice visual effects related to the lens implant. Others notice the effects but are not significantly bothered by them. If you feel you would not be able to adapt to these visual symptoms, you probably are not an ideal candidate for a multifocal lens.
Motivation to not wear glasses should also be determined when selecting a multifocal lens. These lenses are designed for patients who are motivated to not have to wear glasses after their cataract surgery. Some patients are accustomed to wearing glasses and do not mind using them after surgery. The additional cost of a multifocal lens would not be a reasonable investment for these patients. For other patients, eliminating the need for glasses is a strong desire. Paying the additional out-of-pocket cost for a special lens would make much more sense for these patients, as these lenses would give them the best option to achieve their goal to be free from glasses.
In summary, ideal candidates for multifocal lenses are patients with healthy eyes, little to no astigmatism, motivation to be less dependent on eyeglasses or contact lenses, and willingness to adapt to minor visual effects from the lens. Patients selecting a multifocal lens can reasonably expect to have good vision for reading and driving. Because no current technology is perfect there may still be circumstances where glasses are required to achieve a comfortable vision.
Tell me more about astigmatism!
To review, Astigmatism means that the cornea or front window of your eye has an oblong shape and curvature similar to a football. A normal cornea has a more rounded shape similar to a basketball. People with astigmatism do not have clear vision unless they are wearing glasses or contact lenses. During cataract surgery, astigmatism can be treated, resulting in clearer vision. Many people who have astigmatism treated during their cataract surgery can see clearly without glasses for the first time in their life. Low amounts of astigmatism are treated with corneal incisions (limbal relaxing incisions). Using a calibrated diamond blade, very small incisions are placed in the cornea to change the shape of the cornea. Larger amounts of astigmatism are corrected by implanting a special intraocular lens, called a toric lens. Astigmatism treatments are considered by most insurance companies to be an elective component in addition to the cataract procedure and therefore have additional out-of-pocket costs.