You have had your cataract surgery several months or even years ago. Yet recently, you realize your vision is getting blurry and cloudy again, like how it was previously before you had your cataracts removed. 

What is going on? 

This phenomenon is known as posterior subcapsular opacification (PCO),a common occurrence after successful cataract surgery, also known as an after-cataract. Developing PCO should not be a cause of concern as it is a normal degenerative process. Fortunately, you do not require another surgery. 

A simple, painless, quick laser procedure is all it takes to make your vision clear again. Here is a quick comprehensive guide on PCO or ‘after-cataract’.

What causes blurred vision after surgery?

Picture of a patient's eye suffering from PCO

For those who are unaware, cataracts occur when our natural crystalline lens becomes cloudy or opaque due to the natural ageing process. The process of cataract formation can also be accelerated by other environmental factors, such as UV exposure, medications, trauma, etc.

The lens in our eye is surrounded by a capsule. During cataract surgery, an opening is created on the anterior capsule to allow access and removal of the natural lens of the eye. It is then replaced by an artificial lens known as an intraocular lens (IOL). This IOL is placed inside your eye’s lens capsule which used to house your natural lens.

Illustration of the cataract surgery 2

Posterior Subcapsular Opacification (PCO) occurs due to cell proliferation from the microscopic cells within the lens capsule. Over time, these cells will cause the back of the lens capsule to wrinkle and become cloudy. As a result, there will be increased light scattering causing blurry vision and glare. It is likened to looking through a frosted glass window instead of a clear glass window. 

These symptoms are very similar to when you had cataracts previously, hence, PCO is commonly termed as “after-cataracts’’. If you have had cataract surgery in both eyes, PCO can affect both eyes, but each eye may be affected at different times, depending on the speed of cell proliferation in your eye.

How common is PCO after cataract surgery?

It is found that age plays a significant role in the occurrence of PCO. The younger you are when you do your cataract surgery, the likelihood of getting PCO rises. Other factors that can cause PCO to occur are trauma, underlying inflammation of the eye after cataract surgery or if you have underlying eye conditions such as uveitis. However, it is not unusual to develop PCO even if you don’t have any of these conditions.

How do I treat PCO after cataract surgery?

PCO can be easily treated by a procedure called YAG laser capsulotomy. Through the use of a specialized low energy laser in my clinic, I will create an opening in the cloudy lens capsule to allow a clear pathway of light to pass through. This treatment is easily done in my clinic and the painless procedure takes about 15 minutes to complete. There is no downtime and you can regain your clear vision almost immediately after the laser, allowing you to resume any daily activities you have planned for that day.

Picture of a patient eyes after YAG laser

What are the risks of YAG laser capsulotomy?

With the advent of modern technology, the laser used for YAG laser capsulotomy is extremely safe. The risk of YAG laser capsulotomy causing retinal tear or detachment and inflammation are very low. As this is a non-invasive procedure, there is no risk of infections from the laser as the laser light beam travels through the front of your eye without requiring any incisions or wounds. The procedure is extremely safe and all of my patients have undergone this procedure without any complications.

What can I expect on the day of the laser treatment?

When you come into my clinic for your appointment, some eye drops will be instilled into your eye to dilate your pupil. Once your pupils have been sufficiently dilated, a numbing eye drop will be used to anaesthetize the front of your eye so that you do not feel any discomfort. 

I will then use a special contact lens to keep your eye and eyelids in the right position. You may then see some flashes of light and hear some clicking sounds when the laser in being used to remove the opacification. There is no pain or discomfort during the procedure. After clearing the opacification, my assistant will help to rinse your eye with saline water to clean and lubricate the eye.

Dr Claudine Pang serving the patient

Most of my patients are able to see clearly almost immediately after the laser, just as how their vision was after their cataract surgery. It is normal to see some minute floaters after the laser, which will settle over time and become less noticeable. Your near vision will still be a little blurry due to the dilation eye drops and will return to normal after a few hours. You will be able to resume your usual activities after the laser.

Will the PCO return? 

Generally, you only need to do the laser treatment once. It is very rare for PCO to develop again in the same eye.


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