One of my patients, a 65-year-old female, had cataract surgery on her right eye about six months ago. She has been complaining of reduced vision, especially for reading, generally misty vision, and glare around lights at night time. She has 6/12 in her right eye and 6/6 in her left eye. I can’t see a cause for her right eye problems. What is going on?

This sounds like posterior subcapsular thickening following right eye cataract surgery. It is also often known as posterior capsular opacification (PCO).

Posterior capsule thickening can occur in up to 20% of patients over the weeks or months after cataract surgery. Usually, if a person is going to get PCO it will have happened within two years of the cataract surgery, most commonly within the first six months after surgery.

During cataract extraction, the surgeon will carefully remove the cataract from the affected eye, and replace it with an artificial intraocular lens (IOL). The lens is located within a very thin membrane ‘bag’ called the capsule. The front of the capsule must be opened to remove and insert the intraocular lens. The back or ‘posterior’ of the capsule remains intact to support the new lens. In some patients, the outer cells of the old crystalline lens remain and grow on the capsule. The growth of these cells causes the capsule to become hazy or clouded along the visual axis, which results in blurred vision.

The condition is sometimes referred to as a ‘secondary cataract’, although a genuine cataract cannot reoccur after cataract surgery.

The treatment for posterior capsule opacity is simple, quick, and safe and is conducted as an outpatient (walk in, walk out) procedure. A YAG laser is used to remove the layer of cell growth. The moment the cells are removed the visual acuity improves and the other symptoms disappear.

Your patient needs to be referred to an eye specialist with access to a YAG laser.

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