What Is an Intraocular Lens Implant?

Medically Reviewed by Whitney Seltman, OD on August 21, 2022
3 min read

An intraocular lens implant is an artificial replacement for the lens of your eye. It's part of the surgery to fix cataracts.

Each eye has a lens -- a window made of clear protein and water that sits behind the pupil. The lens focuses light onto the retina, which sends it to your brain.

As you get older, the proteins change and parts of your lens turn cloudy. This is known as a cataract. It can make things look blurry or give them a brownish tint.

Cataracts are a leading cause of blindness, especially in older people. But they can be corrected through surgery -- a procedure that's done more than 2 million times a year in the United States.

An intraocular lens implant, or IOL, is made of a clear plastic, and it's about a third the size of a dime. There are several different types:

Monofocal IOL: This is the most common. Unlike your natural lens, which can stretch or bend to help your eye focus, this implant stays focused at one fixed distance. If yours focuses at a distance, you might be able to see things far away but need glasses to read or see close up.

Multifocal implant: Like glasses with bifocal or progressive lenses, this lens has areas that help you see things at different distances. It could take several months for your brain to adapt so your vision seems natural. It can sometimes cause more halos or glare around lights than a monofocal lens. 

Accommodating IOL: This flexible option acts more like your natural lens and focuses at more than one distance. It makes you less likely to need reading glasses.

Toric IOL: You'll get this if you have astigmatism, or a cornea that's more football-shaped than round. This can make vision blurry all over, not just close up or far away. This lens lessens astigmatism so you won't need glasses to correct it after your surgery.

If you have a cataract, you'll see an ophthalmologist for the surgery. This doctor specializes in eye surgery and problems. They'll probably tell you it's best to wait to remove the cataract until it starts to affect your daily life. They can do the surgery at a hospital or an outpatient clinic.

To get you ready, your doctor will:

  • Measure your eye. This will help them pick the right implant for you.
  • Give you medicated eye drops to take for a few days ahead of time
  • Ask you to stop taking some medicines or to skip wearing contact lenses for several days beforehand

On the day of surgery, they'll:

  • Numb your eye
  • Give you a drug to help you relax. You may see light during the procedure, but you should feel nothing or only a gentle pressure.
  • Make a tiny cut through your cornea to get to the lens
  • Break the lens up into pieces and remove it bit by bit
  • Put the implant in place
  • Let the cut heal by itself -- no stitches

You can usually go home in less than an hour, but you'll need someone else to drive.

Any surgery has a chance of complications. It's rare after an intraocular lens implant, but you might notice bleeding or get an infection. Redness or swelling are more common.

More serious risks include:

  • A detached retina, which happens when that layer of nerve cells separates from the back of your eye. This is a medical emergency.
  • Vision loss
  • Dislocation -- when the implant moves out of position

You may also develop an issue anywhere from weeks to years after surgery the tissue around your new lens gets cloudy and your eyesight blurs. This is called an get an after-cataract or Posterior Capsular Opacification. Your doctor can fix this with a painless laser procedure.

It'll take about 8 to 12 weeks to fully heal. During that time:

  • Keep your eye protected with sunglasses as much as possible, and sleep with your eye shield at night.
  • Don't rub or press your eye, even if it's itchy or oozes a bit of fluid.
  • Take the medicated eye drops your doctor prescribes. You'll use them for several weeks to help your eye heal.
  • Avoid most exercise or heavy lifting. The doctor will tell you when you can do those things again.