About Cataracts
A cataract occurs when the lens of the eye becomes cloudy, usually due to the effects of aging. The lens is a clear disk behind the colored iris. The lens plays a part in clear vision by focusing images on the light-sensitive retina at the back of the eye. The retina then sends the visual images through the optic nerve to the brain. If a cloudy lens prevents a sharp image from reaching the retina, vision will be blurry or distorted. More than half of all people in the United States have a cataract or have had cataract surgery by the time they reach age 80, according to the National Eye Institute. Cataracts worsen over time, and in the early stages, it may still be possible to read, drive and perform other tasks. As clouding progresses, the lens may become brown, affecting color vision and making reading more difficult. Surgery may be needed when functional vision is significantly impaired, according to All About Vision.
Preparing for Surgery
During surgery, the cloudy lens is removed from the eye and replaced with an intraocular lens (IOL) implant. Patients choose from a single-vision implant or a presbyopia-correcting intraocular lens. Presbyopia occurs when the lens loses some of its focusing ability, which makes it hard to see near objects. The condition is associated with aging and worsens over time, according to Medline Plus. Use of a presbyopia-correcting intraocular lens corrects this problem, permitting clear vision at any distance after surgery. Patients who choose single-vision implants will still have difficulty seeing close objects clearly if they don't use reading glasses, bifocals or progressive lenses.
Some medications must be stopped before and immediately after cataract surgery to avoid surgical complications. Alpha-blocker medication used to treat prostate problems can cause a condition called intraoperative floppy iris syndrome (IFIS). When IFIS occurs, the pupil suddenly constricts, hindering a surgeon's ability to successfully complete the operation, according to All About Vision.
Cataract Surgery
Before surgery begins, the eye is thoroughly cleaned and a local anesthetic is applied to the eye area. The cloudy lens is removed through a small slit made in the eye near the cornea, the clear covering over the iris. Special instruments inserted into the eye break up the cloudy lens and remove the lens fragments from the eye. The posterior capsule, the back membrane of the lens, is usually left in place to support the implant. The implant is inserted through the incision, replacing the natural lens. The incision usually heals on its own and doesn't require stitches. If surgery is needed on both eyes, surgery will usually be scheduled a few days to a few weeks after the initial surgery to allow the first eye to heal, according to All About Vision.
Recovery
After cataract surgery, an eye shield will be applied to the eye. The shield must be worn while sleeping or napping for a week after surgery. Care must be taken to avoid pressing or rubbing on the eye while it heals. Vision may not be immediately clear. The healing eye needs time to adjust to the implant so that it can focus properly with the other eye, according to the NEI. It may also take some time to adjust to clear vision if vision has been affected by a discolored lens.
