A multifocal lens is an exciting new type of lens implant that allows clear vision at both near and far distances, hence reducing your dependence on reading glasses. The multifocal lens splits light rays into three different channels of vision within the lens implant. These three separate channels of vision provide your brain with information about far, intermediate, and near objects at the same time. Your brain can then decide to pay attention to either the near, intermediate, or distance targets; the brain automatically finds the correct image. Typically the intermediate vision is not quite as strong as the distance and near vision as noted in the diagram below.
The multifocal lens is implanted into the eye in the same fashion as the traditional monofocal lens. But unlike the traditional lens which only gives the ability to focus at one distance, the multifocal lens may improve your ability to see in the distance and to read up close without glasses most of the time.
You will find a simulation below of the simulated vision benefits of a monofocal or standard lens (A) versus a multifocal lens (B) after cataract surgery.
Image A demonstrates clear distance vision after a monofocal or standard lens implantation following cataract surgery. In Image A you can notice that intermediate distance at the dashboard and particularly near vision with the coffee cup are both somewhat blurry. In image B a multifocal lens implantation following cataract surgery demonstrates clear distance vision with the street signs, improved intermediate vision at the dashboard, and clear near vision with the coffee cup.
Not all patients achieve the same amount of success with the multifocal lens, and there can be variability between different patients and different eyes. Even though there is no guarantee that you will be able to read as well as you desire, the multifocal lens will give you a much better chance of spectacle independence than the traditional monofocal lens.
Can the multifocal lens completely eliminate my need for eyeglasses?
Being completely free of glasses is indeed possible, but not guaranteed. Nonetheless, the multifocal lens may reduce your dependence on glasses. Some patients find that certain circumstances such as dim lighting, very small print, and prolonged reading may be easier with reading glasses.
Are there any drawbacks to the multifocal lens implant?
Although the multifocal lens may reduce your dependence on glasses, its design may cause visual disturbances. It may cause you to see halos around lights in dimly lit conditions. The following image gives a simulation of night driving with the multifocal lens.
In this simulated image you will notice that there are halos around the headlights of oncoming cars. In addition there is a slightly “waxy” quality to the vision.
Most patients describe these halos as minor. In addition, as your brain adapts to the design of the multifocal lens, the sensation of halos typically decreases with time.
In addition, a small percentage of patients may have some residual near-sightedness or astigmatism after their cataract surgery. In order to optimize the effect of the multifocal technology and your vision, a separate and free-of-charge laser vision correction (i.e. LASIK or PRK) procedure may be needed a few months after your cataract surgery.
Am I a good candidate for the multifocal lens implant?
The decision to implant a multifocal lens should come with careful deliberation on the part of both the patient and the surgeon. At the Eye Treatment Center your compassionate cataract surgeon will take the time to understand your hobbies, occupation, vision requirements, and expectations. With this information, your surgeon will be better able to personalize your surgical plan. We take the responsibility of assessing your eye’s health to assure that there are no other abnormalities that would hinder your ability to maximize the benefits of the multifocal lens. For instance, certain patients with macular degeneration and advanced glaucoma are not good candidates for the multifocal lens.