PCO: Posterior Capsular Opacification
- Jan 13
- 2 min read
Updated: Feb 23
A complication that can occur after cataracts-removal surgery (also known as phacoemulsification), is Posterior Capsular Opacification (PCO).
This is not an uncommon issue, and while the layman explanation for it is "some dirt left behind", here's a more scientific explanation - still in simple terms that you can understand:
What is PCO?
Posterior Capsule Opacification is the most common late complication after cataract surgery. It is sometimes called a “secondary cataract,” although it is not a true cataract.
Why does it happen?
During cataracts surgery,
- The cloudy lens is removed
- The thin clear capsule that held the natural lens is left in place
- The artificial lens (IOL) sits inside this capsule
Over time, residual lens cells can grow and spread across the back of the capsule, causing it to become cloudy or thickened, therefore affecting how light travels through the eye (and therefore your vision).
Symptoms of PCO
Gradual blurring of vision after the initial improvement post-cataracts-surgery
Glare or halos, especially in bright light
Reduced contrast or clarity, with difficulty reading fine print
These symptoms can appear months or even years after surgery.
How is PCO treated?
PCO is treated with a YAG laser capsulotomy, which:
- Is a quick, painless outpatient procedure
- Takes only a few minutes for the laser itself
- Uses a laser to create a small opening in the cloudy capsule
- Restores clear vision almost immediately in most patients
No incision is made, and recovery is usually very fast, with patients being discharged in the day itself. The effects of the eye drops used may take several hours to gradually wear off, and driving is to be avoided in the meantime.
Fun fact: YAG stands for yttrium aluminum garnet, a crystalline material used in the production of the laser used to treat PCO.
Can PCO come back?
PCO does not usually recur after laser treatment.
Most patients need the procedure only once to treat PCO.
Still unsure? Come visit us and we will make it clear. Schedule an appointment by contacting us here.
