---
title: What is posterior capsule clouding?
description: "Posterior capsule clouding, also known as posterior capsule opacification (PCO), is a common late complication after [cataract surgery](https://bluefinvision.com/cataract-surgery/). It occurs when the thin membrane behind the lens implant becomes hazy. ## Why It Happens Residual lens cells left behind at…"
url: "https://bluefinvision.com/knowledge-base/topics/conditions-diseases/what-is-posterior-capsule-clouding/"
updated: "2025-12-11"
category: "Conditions & Diseases"
---

# What is posterior capsule clouding?

Posterior capsule clouding, also known as posterior capsule opacification (PCO), is a common late complication after [cataract surgery](https://bluefinvision.com/cataract-surgery/). It occurs when the thin membrane behind the lens implant becomes hazy.

## Why It Happens

Residual lens cells left behind at surgery can grow and migrate across the capsule, forming a cloudy layer. This scatters light in a similar way to the original cataract.

- Symptoms include blurred vision, glare, and reduced contrast
- PCO may develop months or years after surgery
- It is not a 're-growth' of the cataract but a membrane change

## Treatment

PCO is usually treated with a quick outpatient YAG laser capsulotomy, which creates a small opening in the cloudy capsule. This allows light to pass freely again and often restores vision rapidly.

## Further Information

The Blue Fin Vision® blog article on [blurred vision after cataract surgery](https://bluefinvision.com/blog/blurred-vision-2-years-after-cataract-surgery-causes-and-solutions/) explains how PCO is identified and managed.