Posterior Capsular Opacification

Posterior capsular opacification (secondary cataract) is a clouding of the thin membrane (lens capsule) that surrounds your newly implanted IOL. It’s a common complication of cataract surgery that can occur months or years afterward, causing fuzzy vision. Your provider can easily treat a secondary cataract through a quick laser procedure.


What is posterior capsular opacification?

Posterior capsular opacification (secondary cataract) is a clouding of your eye’s lens capsule that can occur as a complication of cataract surgery. Cataract surgery is a common procedure that treats cataracts, or cloudy patches that form on your eye’s natural lens. Cataracts are a natural part of aging, and surgery is the only way to treat them.

During cataract surgery, an ophthalmologist removes your eye’s natural lens and replaces it with an intraocular lens (IOL). This new IOL is clear and restores your vision. Most people are happy with the results of their cataract surgery. However, one common (but easily treatable) complication is the development of a secondary cataract.

You might think that a secondary cataract means the cataract you had before has returned. This isn’t possible. The cloudy patches that healthcare providers call cataracts only form on a natural, crystalline lens. This is the lens in your eye that you were born with. Cataracts can’t form on artificial lenses (IOLs). Instead, with posterior capsular opacification, you develop cloudy patches on your lens capsule.

Your lens capsule is a thin membrane that surrounds your lens and provides its shape. Cataract surgery removes your lens but not the capsule. You can think of your lens capsule like a tiny apartment that receives a new tenant. When your natural lens moves out, your IOL moves in. The capsule is still there in your eye, and it’s still the same home. It’s made of cells and other natural materials, and it’s normally clear. But like your natural lens, it can develop cloudy patches over time.

These cloudy patches, or secondary cataracts, may form as part of your eye’s healing process after surgery. If this happens to you, your provider can remove the secondary cataract through a quick, outpatient laser procedure.

How long after cataract surgery can posterior capsular opacification occur?

A secondary cataract can develop months or years after your cataract surgery.

How common are secondary cataracts?

Secondary cataracts are the most common complication of cataract surgery. They affect up to 50% of people who have cataract surgery within five years of the surgery.


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Symptoms and Causes

What are the symptoms?

Posterior capsular opacification symptoms include:

  • Cloudy, blurred or fuzzy vision. It may seem like you’re looking through frosted glass.
  • Glare or haloes around lights.
  • Sensitivity to light.
  • Trouble reading.

These symptoms resemble typical cataract symptoms prior to surgery.

What causes posterior capsular opacification?

When your provider removes your eye’s natural lens during cataract surgery, there can still be some lens epithelial cells left over. These cells travel and collect on the surface of your lens capsule. Healthcare providers call this process cell migration, and it’s actually part of your body’s normal healing process. As these cells build up, they cause your capsule, which is normally clear, to grow cloudy.

If you think of your lens capsule as an apartment that houses your lens, then you can picture dirt gradually building up on your apartment window. This cloudiness affects your ability to see out your window (or your eye) as you normally would. So, you begin to experience the same symptoms that led you to have cataract surgery in the first place.

What are the risk factors for a secondary cataract?

Anyone who has cataract surgery faces the risk of a secondary cataract. However, your risk may be higher if you have any of the following conditions:

You may also face a higher risk if you had a complication (like eye swelling) during or soon after your cataract surgery.


Diagnosis and Tests

How is a secondary cataract diagnosed?

Eye care specialists diagnose posterior capsular opacification through a careful eye exam, which includes a slit lamp exam. This is a painless test that allows your provider to get a close look inside your eye. Your provider will also ask about your medical history and your history of eye surgery to reach a diagnosis.

Management and Treatment

What is the treatment for posterior capsular opacification?

Healthcare providers treat secondary cataracts with YAG laser capsulotomy (posterior capsulotomy). This is a laser surgery that your provider performs in-office. It only takes around five minutes. “YAG” is the name of the specific type of laser that your provider uses.

During this procedure, your provider numbs your eye with drops. Then, they use lasers to make a tiny hole in your cloudy lens capsule. This hole lets light pass through your IOL, as it should, and gives you back your clear vision.

How soon after treatment will I feel better?

It takes about one day for your vision to clear up after YAG laser capsulotomy. You may experience floaters for a couple of weeks before they dissipate. The floaters are debris removed during laser treatment, and they’ll naturally dissolve over time.

What are possible complications of treatment?

YAG laser capsulotomy has a low risk of serious complications. However, possible complications include:

  • Retinal detachment. You may face a higher risk if you have a high degree of nearsightedness.
  • Increased pressure in your eye. People who have glaucoma face a higher risk.
  • IOL dislocation. This means your IOL moves out of place.

Can posterior capsular opacification go away by itself?

No, you need treatment for a secondary cataract to see clearly again. You should see your provider if you develop symptoms.


Can secondary cataracts be prevented?

There’s nothing you can do to prevent a secondary cataract. However, researchers are looking into new surgical methods and IOL technologies that may lower a person’s risk. You may wish to talk to your provider about these latest advancements to learn more.

Outlook / Prognosis

Does posterior capsular opacification go away?

Yes, with treatment, secondary cataracts can quickly go away. You should feel better and see clearly again about 24 hours after your laser surgery.

Does posterior capsule opacification get worse over time?

Your symptoms may get worse over time as your lens capsule grows cloudier. It’s important to see your provider as soon as you notice new symptoms so they can diagnose and treat the problem.

What is the outlook for this condition?

Most people have an excellent outlook after treatment for secondary cataracts. Rarely, another secondary cataract can form on your lens capsule. If this happens, your provider can treat it again with the same laser procedure.

Living With

When should I call my healthcare provider?

Call your provider if you have symptoms of a secondary cataract. It’s important not to delay care since such symptoms (like changes in your vision) can signal many possible problems, aside from a secondary cataract. Your provider may ask you to come in for an exam so they can find out what’s wrong and give you the proper treatment.

When should I seek emergency care?

Go to the emergency room immediately if you have signs of retinal detachment:

  • Sudden, new onset of floaters.
  • Flashes of light that you can see with your eyes open or closed.
  • A shadow or curtain that seems to spread across your line of vision.

The sooner you receive medical care, the better your chances of successful treatment. Delay in care can lead to permanent vision loss.

What questions should I ask my doctor?

If you’re having cataract surgery, you may want to ask your provider:

  • What’s my risk for a secondary cataract?
  • What can you do to lower that risk?
  • When is a secondary cataract most likely to develop?
  • What symptoms should I look out for?

If you’re having laser surgery to treat a secondary cataract, ask your provider:

  • What can I expect during this surgery?
  • What’s the recovery like?
  • When will my vision return to normal?
  • What are the risks of this procedure for me?
  • What can you do to lower my risk of complications?
  • What are the chances of a secondary cataract forming again later on?

A note from Cleveland Clinic

No one wants to have a complication after surgery. And if one does occur, you may feel frustrated or upset. Rest assured that secondary cataracts are a common complication of cataract surgery. Healthcare providers know how to treat them, and they’re confident that you’ll quickly regain your clear vision and go on with life as normal.

Still, it’s important to talk to your provider about the risk of complications any time you have a procedure, including cataract surgery or laser surgery to treat secondary cataracts. Learning about the risks can ease your mind about what’s to come and also prepare you for any bumps in the road.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 02/14/2023.

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