When is cataract surgery needed? When cataracts reduce vision so that normal activities become difficult, it is time to consider surgery, which is the only way to remove cataracts.

It is primarily the patient who determines when surgery is needed. Some patients have mild cataracts but major problems with glare and halos that make it difficult to drive a car at night or fly a plane, for example. If it is determined that these complaints are due to cataracts, surgery can be considered. Other patients may have more advanced cataracts but few complaints. For example, a patient who no longer drives and only needs to watch TV and read with a bright light may have little difficulty, and so surgery would not be needed. The concept that the cataract is "ripe" or ready is no longer considered a valid indication for surgery.

What about safety and effectiveness? Today, cataract surgery with intraocular lens (IOL) implants usually takes less than an hour and results in vision improvement for most patients. Although any surgery carries risk, cataract-IOL surgery is uncomplicated and successful in more than 95 percent of patients.

Who does the surgery? An Eye M.D. (ophthalmologist) performs the surgery. It is important to discuss the surgery and the choice of an intraocular lens (IOL) implant to correct your vision with your Eye M.D. and to ask any questions you may have.

What happens during surgery?

• Topical or local anesthesia is used so that the operation will be painless. You will not need to be concerned about keeping your eye open during the procedure. You may notice light or movement but will not be able to see the surgery as it is performed.
• Phacoemulsification is the most effective and common cataract removal method in use today.  After the eye is numbed with anesthetic, a small incision is made in the side of the cornea (the front window of the eye). A tiny ultrasound instrument is inserted and used to break up the cloudy lens, which is then suctioned out of the eye. In rare cases another technique called extracapsular extraction of the cataract is required instead.
• Next, an IOL is inserted to replace the natural lens. Usually it is placed behind the iris, the colored part of the eye. Stitches are often not needed, but when used they dissolve naturally over time.

What to expect before and after surgery:

• To determine your IOL prescription, your eye’s length will be measured by ultrasound (the “A-scan”) and the cornea’s curvature will be measured by a process called keratotomy. If you have had LASIK or other laser refractive surgery, provide your pre-surgery vision correction prescription (PDF 650K) to your Eye M.D., if possible. The record of this prescription is also called the “K card”.
• Your Eye M.D. will review your eye health and overall medical history. Be sure to tell your doctor if you are currently or have ever used alpha-blocker medications such as Flomax®, Hytrin®, Uroxatral®  or Cadura®. These medications can cause the iris to move out of its normal position, which can lead to complications during cataract surgery. You can still have successful surgery if your surgeon knows you have taken these drugs and alters his or her surgical technique.  Also tell your Eye M.D. about any other medications you are taking.
• On the surgery day you may be asked to skip breakfast. Before surgery you’ll receive eyedrops and perhaps medication to help you relax.
• Your Eye M.D. will perform surgery on only one eye at a time. If both eyes need cataract removal and IOLs, the second procedure will usually take place within a few weeks. The interval allows your doctor to monitor your progress after the first surgery and make sure no complications arise, or to treat a complication in the unlikely event one does occur.
• After surgery, the doctor may place a shield over your eye. After a brief stay in the recovery room, you can go home. Since you will not be able to drive after surgery arrange for someone to take you home. You can resume most normal activities the same day.

Caring for your eyes after surgery:

• It is important to follow your Eye M.D.’s instructions to help your eyes heal and avoid complications.
  Apply eye drops properly:
  1. Tilt your head back.
  2. Pull your lower lid away from the eye to form a pocket.
  3. Let the drop fall into the pocket without touching the bottle to your eye or eyelid.
  4. Close your eye for three minutes, then blink and close the eye again.
  5. Wipe away unabsorbed drops and tears before opening the eye.
• If your doctor has given you more than one eye drop medication, wait three to five minutes between applying each medication.
• If prescribed by your doctor, wear an eye shield or eyeglasses to protect your eye during healing.
• Do not rub or press the eye as this can disturb healing and cause irritation.
• Resume your normal activities, with the exceptions of driving and strenuous exercise. Most Eye M.D.s ask their patients to take it easy for the first few days, and to refrain from bending over, picking up heavy objects, and swimming. Use good common sense, and avoid any circumstances where the eye could be hit or injured. More vigorous activities may be resumed after a week or two, with the approval of your Eye M.D.
• You will have follow-up visits with your Eye M.D. to insure proper healing and good vision.
• Get more information about vision correction with IOLs, eyeglasses or contact lenses.

In some cases the capsule that supports the IOL becomes cloudy months or years after cataract removal. Your Eye M.D. can correct this by using a laser to make an opening in the center of the membrane. This is called a posterior capsulotomy and can be done in about five minutes in the doctor’s office. No recovery period is needed.

Last reviewed and updated in May 2009,
by the American Academy of Ophthalmology.