Will multifocal LASIK eye surgery do away with your bifocals?
If you are in your 40s, you are probably starting to feel the frustration of being unable to read books and menus up close. When you find yourself buying your first pair of reading glasses, you can blame presbyopia. As you get older, your eye loses the ability to focus properly. Presbyopia is unavoidable, although a number of procedures and devices have been developed to help deal with it. Until recently, however, LASIK eye surgery has not been available to fix presbyopia. Multifocal LASIK surgery may provide an easy solution for presbyopia.
In standard LASIK eye surgery the shape of the cornea is changed permanently in an attempt to correct the patient’s vision. The ophthalmologist makes a small cut in the cornea to expose the stroma, the middle section of the cornea. A laser is then used to reshape the curvature of the stroma, allowing the eye to bring things into sharper focus. Standard LASIK surgery, however, cannot fix presbyopia because is still leaves the cornea with a uniform curvature. The eye is still unable to refocus on different objects with the ease it did when the patient was young.
In multifocal LASIK surgery the cornea is given multiple curvatures. This allows different parts of the cornea to focus differently. In a sense, the surgery is designed to create bifocals directly on the patient’s corneas.
Multifocal LASIK surgery can provide an obvious benefit for the over 100 million Americans who suffer from presbyopia: freedom from bifocals! It is provides an alternative to more evasive procedures such as lens replacement surgery. In lens replacement surgery, the patient’s natural lens is replaced with an artificial lens. In multifocal LASIK surgery, the natural lens is just reshaped.
Multifocal LASIK eye surgery is still a relatively new procedure. However, a number of trials in the United States and Canada have returned promising results. In one study, conducted by Dr. Bruce Jackson of Ottawa, patients received standard LASIK on one eye, and multifocal LASIK on the other. All the patients in the study were happy with their long distance vision, and 86% were satisfied with the sharpness and clarity of their vision.
LASIK surgery is a permanent procedure. However, if the patient is not fully satisfied with his or her standard LASIK surgery, the patient can undergo secondary enhancement surgery. This secondary surgery attempts to reshape the corena a second time to account for any problems the patient may experience with the initial surgery. Between 5 and 20% of LASIK surgery patients require secondary enhancement surgery. Secondary enhancement surgery, however, cannot be performed on patients who underwent multifocal LASIK surgery. This means that as many as 20% of multifocal patients will be unsatisfied with their surgery, but unable to easily fix their vision.
While the idea of fixing presbyopia with multifocal LASIK is promising, anyone thinking of using this procedure should strongly consider his or her other options. Indeed, despite promising trials, the FDA has not yet approved the use of multifocal LASIK surgery in the United States.