Posterior capsular opacification, or secondary cataract, is a common complication of cataract surgery. It can get worse without treatment, but a quick laser procedure by an ophthalmologist can cure it.

Posterior capsular opacification (PCO) happens when the thin capsule surrounding the lens in the front of your eye becomes cloudy. It’s a common complication of surgery to treat cataracts and can cause symptoms similar to those of the original cataract. That’s why people often refer to PCO as secondary cataracts.

Doctors can treat PCOs with laser surgery to create a hole in your capsule. This surgery can usually improve your vision and has low rates of complications. People who have this surgery often experience symptom improvement within 24 hours.

Read on to learn more about secondary cataracts, including what causes them and how doctors treat them.

secondary cataract, also known as a posterior capsular opacificationShare on Pinterest
A PCO, or secondary cataract, can cause cloudiness in your vision after cataract surgery.
Copyright © 2005 El Saghir et al; licensee BioMed Central Ltd.CC BY 2.0

The development of a PCO is the most common complication of cataract surgery. It’s your body’s wound-healing response to the procedure.

During cataract surgery, a surgeon removes the lens at the front of your eye and replaces it with a synthetic lens. This replacement lens can’t develop another cataract since it’s not made from biologically active tissue. Instead, a PCO develops in the thin layer of tissue that surrounds the replacement lens and helps give it its shape.

Secondary cataracts are very common after cataract surgery. A 2021 analysis from the United Kingdom’s Royal College of Ophthalmologists found that PCOs occurred in:

  • 4% of people within the first year after cataract surgery
  • 18% of people within 3 years
  • 31.2% of people within 5 years

Children seem particularly likely to develop PCOs after surgery, with rates of nearly 100%. Cataracts can develop in children as a result of conditions such as:

  • traumatic eye injury
  • infections that transfer from a parent to a child during pregnancy
  • genetic conditions
  • atypical development of the lens before birth

Risk factors for the development of a secondary cataract after surgery seem to include:

Primary vs. secondary cataract

Primary cataracts are often simply called cataracts. They involve clouding of the clear lens at the front of your eye, which allows you to focus your vision at various distances. Eye injuries, smoking, and too much sun exposure can speed up cataract development.

Primary cataracts become more common with age and affect more than 20.5 million U.S. adults ages 40 years and older.

Secondary cataract is a possible complication of surgery to remove a primary cataract.

The symptoms of a PCO are similar to those of a cataract. The main symptom is cloudiness in your vision, which leads to reduced vision quality. Some people describe the clouding as being similar to looking through a frosted sheet of glass.

Other possible signs and symptoms include:

The primary treatment for a PCO is a surgical procedure called a YAG laser capsulotomy or posterior capsulotomy. (“YAG” stands for “yttrium aluminum garnet,” a material used in the laser.)

During this procedure, an eye doctor uses a laser to create an opening in your cloudy capsule that allows light to pass through.

According to the American Academy of Ophthalmology, you can undergo YAG laser capsulotomy in an ophthalmologist’s office or an outpatient surgical center. It takes about 5 minutes.

Here’s a general idea of what YAG laser capsulotomy involves:

  1. An ophthalmologist will numb your eyes with eye drops. They may also give separate drops to dilate your pupil.
  2. The ophthalmologist will point a special laser at your lens capsule to make a small opening. You shouldn’t feel any pain during the procedure.
  3. Afterward, you may need to use eye drop medications for a few days.

How many times can you get a secondary cataract?

PCOs generally develop only once. After you receive treatment to make a hole in your capsule, the PCO is highly unlikely to return.

In a 2019 case study, a researcher reported on a 70-year-old woman who needed a second surgery 7 months after her cataract surgery to treat the redevelopment of her secondary cataract.

The outlook for people who have a PCO and receive surgery is generally excellent. You’ll likely have vision improvement in about 24 hours after surgery if you don’t have any other vision problems.

Although complication rates for this surgery are low, it’s possible that you’ll develop side effects such as:

People who don’t have access to surgery can have severe vision loss that can disrupt their life.

How serious is a secondary cataract?

PCOs can be debilitating for people who don’t have access to corrective surgery. People who do receive surgery usually have excellent vision improvement.

Do secondary cataracts get worse?

PCOs tend to get progressively worse until they’re treated by an ophthalmologist.

What is the recovery time after YAG surgery?

Most people who have YAG laser capsulotomy experience vision improvements within 24 hours. You may have some vision changes for days to weeks after your procedure, such as “spider-like” floaters.

A PCO, or secondary cataract, is the most common complication of surgery to remove a cataract. It develops when the capsule around your lens becomes cloudy as part of your body’s wound-healing response.

Ophthalmologists can often successfully treat PCOs with YAG laser surgery to make a hole in your capsule. Many people who receive this surgery have vision improvement within 24 hours if they don’t develop complications.