What Is Glaucoma?
Glaucoma occurs when the optic nerve becomes increasingly damaged, usually as a result of high pressure inside the eye. Our optic nerve is responsible for transmitting visual information from our eyes to our brain. Though glaucoma is typically related to high intraocular pressure, it can also occur even when the intraocular pressure is within the normal range.
Though there are many different types of glaucoma, the 3 most common are:
Open-angle glaucoma is the most common form of the disease, with over 250,000 Canadians managing its symptoms.
It occurs when your intraocular pressure rises due to blockages in your eye’s drainage canals (trabecular meshwork), but the drainage angle between your iris remains open. Because your eyes internal fluids (aqueous humour) aren’t draining at a normal rate, your intraocular pressure rises and damages your optic nerve, leading to vision loss.
Closed-angle glaucoma, or acute angle-closure glaucoma, is less common than its open-angle counterpart but is much more damaging to your vision.
This disease occurs when the drainage angle between your iris and cornea closes, resulting in the rapid rise of intraocular pressure, leading to vision loss. Closed-angle glaucoma can also cause other symptoms like:
- Eye pain
- Blurry vision
- Light halos
- Red eyes
Closed-angle glaucoma is considered to be a medical emergency and requires immediate attention.
Normal-tension glaucoma is unique in its ability to damage your optic nerve without raising your intraocular pressure. Experts still are not sure what causes the disease, but routine comprehensive eye exams can detect it.