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Why Doctors Remove Cataracts

Perhaps the first thing you'll notice is a glare from oncoming headlights at night. Usually, a haze surrounds the lights.

Then, you're likely to find reading more challenging. It's harder to see the letters, and they tend to blur together.

This is what happens when you develop cataracts.

A cataract is a clouding of the eye's lens, a clear, soft gelatinous structure behind the pupil that works much like a camera lens. The leading cause of cataracts is aging. Other contributing factors include:

  • Genetics

  • Sunlight

  • Metabolic diseases such as diabetes

  • Some medications, including lengthy use of corticosteroids such as cortisone or prednisone

When cataracts affect your ability to function, it's time to consider surgery.

Many people think surgeons take the cataract off the eye. Actually, the entire lens is removed and a synthetic lens, called an IOL or intraocular lens, is implanted. This new lens includes a prescription, much like eyeglasses. Still, you'll probably need prescription glasses, especially for reading.

In most cases, patients receive a sedative before surgery but remain awake throughout the procedure. Some surgeons give numbing injections around the eye, but anesthetic drops can be used instead.

Once the anesthetic is working, the surgeon makes an incision in the eye to help reach the cataract and implant the new lens. The surgeon usually uses ultrasound energy to liquefy the cataract-clouded lens (phacoemulsification). That lets them remove the remains of the lens through a tube in a suction-like process called aspiration.

The painless procedure takes about 15 to 30 minutes per eye. Complex cases are unusual but require more care.

If both eyes have cataracts, you're usually operated on at different times, generally weeks apart. This is done for your safety.

This is done to ensure that the first eye has healed without complications before performing surgery on the other eye. Patients go home the same day and wear a patch or shield to protect the eye. Then the eye is examined the next day, a week after the surgery, and a month later.