Many people today choose to correct their refractive errors with techniques other than wearing eyeglasses or contact lenses. Surgeries such as laser-assisted in situ keratomileusis, or LASIK, can improve vision by permanently changing the shape of the cornea to redirect how light focuses on the retina. However, in some cases, instead of reshaping the cornea, the focusing power of the eye’s natural lens is enhanced by implanting a special kind of intraocular lens (IOL), called a phakic IOL, to treat myopia (nearsightedness). Currently, phakic IOLs are not yet approved to treat hyperopia (farsightedness). They are especially useful in cases when a patient has thin corneas or requires a large correction that may not be readily achievable using other refractive procedures.
The surgical procedure usually takes about 15 to 30 minutes and is performed on an outpatient basis. The procedure actually begins one week before the surgery, when your surgeon uses a special laser called a YAG laserto create two tiny holes in periphery of your iris (the colored part of your eye) to reduce one of the rare complications of this procedure, called pupillary block glaucoma. At the time of surgery, eyedrops are instilled in the eye to increase pupil size if the lens is to be placed behind the iris or to reduce pupil size if the lens is to be placed in front of the iris. Drops to numb the eyes are administered as well. Your ophthalmologist (Eye M.D.) then makes an incision and inserts the IOL either in front of the iris or between the iris and your natural lens, depending on the type of phakic IOL being used. To close the incision, your ophthalmologist makes tiny stitches, which are either dissolvable or may need to be removed in the future. You will also be fitted with an eye shield to wear for a short time following surgery.
After the procedure, vision is usually instantly improved, although you may experience some mild discomfort. You will need to return for an exam the day after surgery, and you will have a series of routine follow-up visits as well. Most patients are able to drive and return to work the next day. You will need to use antibiotic and steroid eyedrops several times a day, usually for the first week following surgery.
Reversibility appears to be a big advantage of phakic IOLs over many other forms of refractive surgery. The implant can be removed if complications occur or the correction no longer is effective.
Complications are rare but can occur following implantation of phakic IOLs. Risks associated with implanting IOLs include overcorrection or undercorrection, infection, increased “floaters” or retinal detachment, cataracts, dislocation of the implant, halos and glare, dry eye, decreased contrast sensitivity, swelling in the cornea, damage to the optic nerve, and loss of vision.
Phakic IOLs are a relatively new technology; long-term effects and potential risks of lens implantation are unknown.
You and your ophthalmologist should decide together if phakic IOLs are the best treatment option for your specific condition.
(c) 2007 The American Academy of Ophthalmology
This post was written by Rob Schertzer