Cataracts

Light rays enter the front of your eye and are interpreted by your brain as images.  Light rays first enter your eye through the cornea, the “window” of your eye.  The cornea is a clear dome.  The cornea and lens in your eye work together to help you focus.  The lens is a clear curved disc.  The ciliary muscles adjust the curve in the lens to focus clear images on the retina.  The retina is located at the back of your eye.  Information from the retina is transmitted along nerve pathways to your brain, where you process and perceive vision.

A cataract results from a clouding of the lens that affects vision.  The lens is made of mostly water and protein.  Ordinarily, the protein in the lens is arranged so that light can pass through it.  Cataracts form when the proteins move together and cloud an area of the lens.  Cataracts are a brown-yellow color, which may affect a person's color vision.  Cataracts are slow growing, but they can gradually grow large enough to make it difficult to see. 
 
Cataracts are a common condition in older adults.  The tendency to have cataracts may be inherited.  Smoking, alcohol use, diabetes, eye injury, radiation, certain medications, and toxic substances may contribute to cataract formation.  Babies of mothers with certain risk factors may be born with cataracts or develop them in childhood.

Cataracts are a slow growing progressive condition.  A cataract can develop in one eye or both eyes.  It does not spread from one eye to the other.  Cataracts do not typically cause pain, and you may not realize you have them at first.
 
As a cataract grows, you may notice symptoms.  A cataract may make it difficult for you to see at night or read.  You may experience double vision or multiple images in just one eye.  Your eyes may be sensitive to glare.  You may see halos around lights.  Your vision may be blurred, cloudy, fuzzy, or filmy as a cataract decreases the amount of light that enters your eye.  As the lens gradually turns a brown-yellow color, it may be difficult to distinguish blues and purples.

Your doctor can diagnose a cataract by reviewing your medical history and conducting a thorough eye examination.  You should tell your doctor about your symptoms.  Your doctor will dilate your pupils and view your inner eye structures with special lighted equipment, a slit lamp and ophthalmoscope.  Tonometry is used to measure the pressure in your eyes.  A visual acuity test is used to determine how well you see at different distances.  Imaging tests may be used to produce pictures of your inner eye.  Ultrasound, also referred to as echography, uses high frequency sound waves to produce images of the internal eye structures.

The symptoms of an early cataract may be relieved with new glasses, anti-glare sunglasses, and over-the-shoulder lighting for reading.  A cataract only needs to be removed when vision loss interferes with your everyday activities.  However, some people never need cataract surgery.  If you have cataracts in both of your eyes that need to be removed, your surgeon will remove them one at a time.  The second cataract may be removed a few weeks after the first one.
 
Cataract surgery is one of the most common surgery procedures in the United States.  It is a short procedure with minimal pain and minimal risk.  The surgery is perfomed on an outpatient basis.  You may stay awake for the surgery with anesthesia to numb the area or you may use a general anesthesia to put you to sleep for a short time.  You will need to have another person drive you home following your procedure.
 
Cataract surgery involves surgically removing the lens in the eye and replacing it with an artificial one.  There are two main types of cataract surgery.  Phacoemulsification, also called phaco or small incision cataract surgery, uses a tiny inserted probe that emits sound waves to break up the lens.  The lens is removed with suction.  Extracapsular surgery involves removing the cloudy part of the lens in one piece and removing the rest of the lens by suction.  The phacoemulsification method is used most frequently.  Your doctor will discuss the surgeries in detail and help determine which method is the best for you.
 
After the cataract is removed, the lens is replaced with an artificial intraocular lens (IOL).  The IOL is made of clear plastic or silicone.  It is carefully measured and fitted just for you.  The IOL is a permanent part of your eye and requires no care.  You will not be able to see or feel it.  Select people may not be able to receive an IOL because of eye disease or problems from surgery.  Instead, they may use a soft contact lens or high magnification glasses. 
 
Initially, you will wear a patch over your eye to protect it.  You will need to wear an eye shield or protective glasses as your eye heals.  Your doctor may prescribe eye drops to promote healing and reduce the chance of infection.  You should avoid bending at the waist, heavy lifting, or heavy chores while your eye heals. 
 
Your surgeon will monitor your healing progress with follow-up appointments.  Complete healing usually takes about eight to ten weeks.  The majority of people have excellent results with cataract surgery.