1. Primary open-angle glaucoma 

This is the most common type of glaucoma. It happens gradually, where the eye does not drain fluid as well as it should (like a clogged drain). As a result, eye pressure builds up and starts to damage the optic nerve. This type of glaucoma is painless and causes no vision changes at first. Some people have optic nerves that are sensitive to normal eye pressure. This means their risk of getting glaucoma is higher than normal. Regular eye exams are important to find early signs of damage to their optic nerve. This is called low tension glaucoma. 

2. Angle-closure glaucoma (also called ‘closed-angle glaucoma’ or ‘narrow-angle glaucoma’) 

This type of glaucoma happens when someone’s iris is very close to the drainage angle in their eye. The iris can end up blocking the drainage angle. You can think of it like a piece of paper sliding over as sink drain. When the drainage angle gets completely blocked, eye pressure rises very quickly. This is called an acute glaucoma. It is a true eye emergency, and you should call your ophthalmologist right away or you might go blind. 

3. Low-tension glaucoma 

In low-tension glaucoma, the optic nerve gets damaged despite the patient having normal eye pressure. This also requires treatment. 

Here are the signs of an acute angle-closure glaucoma attack :

• Your vision is suddenly blurry 

• You have severe eye pain 

• You have a headache 

• You feel nauseous 

• You are vomiting 

• You see rainbow-colored rings or halo’s around lights 

Many people with angle-closure glaucoma develop it slowly. This is called chronic angle-closure glaucoma. There are no symptoms at first, so they don’t know they have it until the damage is severe or they have an acute attack. 

Angle-closure glaucoma can cause blindness if left untreated. 

Treatment of Glaucoma is of the utmost importance. The damage caused by glaucoma can’t be reversed, but treatment and regular checkups can help slow or prevent vision loss, especially if you catch the disease in its early stages. 

Glaucoma is treated by lowering your eye pressure (intraocular pressure). Depending on your situation, your options may include prescription eyedrops, oral medication, laser treatment, surgery or a combination of any of these.