The lens of the eye is normally transparent. If a cloudy area develops in the lens, it is called a cataract. Vision becomes increasingly poor as light passing through the cataract is decreased and scattered. Early symptoms include glare and sensitivity to bright light. Later, as the cataract continues toworsen, haloes may appear around lights. Vision often becomes blurred, hazy and foggy.
Cataracts develop as a normal part of aging. They usually develop slowly and at a different rate within each eye. Some years may pass before the cataract interferes with vision enough for a person to seek expert advice. By the age of 70, nearly everyone has some degree of cataract formation. Diabetes, various eye diseases, eye injury or excessive exposure to ultraviolet light may also cause cataracts.
Surgery is needed to remove the cloudy lens and replace it with a permanently implanted artificial lens, called an intraocular lens (IOL). This transparent plastic disc has a similar shape to the natural lens. Many different types of IOL are available to suit different cases.
YOUR MEDICAL HISTORY
Your ophthalmologist needs to know your medical history to plan the best treatment for you. Tell your ophthalmologist about any health problems you have. Some may interfere with surgery, anaesthesia, recovery and ongoing medical treatment following recovery.
A DECISION TO HAVE CATARACT SURGERY
As you make the decision whether to have surgery, make sure that you understand the risks, benefits and limitations of surgery. If you do not have surgery, your symptoms and condition may continue to worsen. Once a lens becomes cloudy, it will not recover its normal clarity.
Only you can decide if surgery is right for you. If you have any questions, ask your ophthalmologist.
Cataract surgery is usually performed under local anaesthesia and light sedation.
Different types of cataract surgery include:
Phacoemulsification – the surgeon makes a small incision near the border of the cornea and sclera, or in the cornea. A small vibrating probe is inserted into the lens capsule to divide the lens into pieces. The pieces are gently suctioned away. The IOL is inserted.
Extracapsular cataract extraction – the surgeon makes a 10–12mm incision near the border of the cornea and the sclera, or in the cornea. The lens is removed from the lens capsule. The IOL is inserted.
Intracapsular extraction – the surgeon removes the entire lens and lens capsule, and then inserts the IOL. Your ophthalmologist will usually wait until your first eye has healed before operating on your second eye.
POSSIBLE RISKS AND COMPLICATIONS
Cataract surgery is safe but does have risks of complications. These are outlined in the complete RANZCO patient education pamphlet and should be discussed with your ophthalmologist.