Glaucoma is a group of eye diseases that affect the optic nerve, which connects the eye to the brain. It often affects both eyes, usually to varying degrees.
In New Zealand, it's estimated more than 91,000 people have glaucoma but as many as 50 percent do not know they have the condition.
Glaucoma can be treated but early detection is important. If left untreated, glaucoma can cause visual impairment and damage that cannot be reversed.
Specsavers Optometrist Ian Russel talks to AM about different types of glaucoma, risk factors and ways to manage the condition. Watch the video above to learn more.
This article was created for Specsavers.