Glaucoma is an eye condition that damages the optic nerve, the nerve which supplies visual information to your brain from your eyes. Glaucoma is usually a result of abnormally high pressure inside your eye.
The back of your eye continuously makes a clear fluid called aqueous humor. As this fluid is made, it fills the front part of your eye. The fluid then leaves your eye through channels in your iris and cornea. If these channels are blocked or partially obstructed, the natural pressure in your eye, which is called the intraocular pressure (IOP), may increase. As your IOP increases, your optic nerve may become damaged. As damage to your nerve progresses, you may begin losing sight in your eye.
What causes the pressure in your eye to increase isn’t always known. However, doctors believe one or more of these factors may play a role:
- genetic inheritance
- dilating eye drops
- blocked or restricted drainage in your eye
- medications, such as corticosteroids
- poor or reduced blood flow to your optic nerve
Over time, the increased pressure can erode your optic nerve tissue, which may lead to vision loss or even blindness. If it’s caught early, you may be able to prevent additional vision loss.
There are five major types of Glaucoma, and these types are categorised as follows:
Angle-closure Glaucoma: This type of Glaucoma, also called closed-angle Glaucoma or narrow-angle Glaucoma, is a less common form of the disease. It is a medical emergency that can cause rapid vision loss, and it occurs when the drainage angle in the eye (formed by the cornea and the iris) suddenly closes or becomes blocked. Many people who develop this type of Glaucoma are born with a very narrow drainage angle. With age, the lens in the eye becomes larger, pushing the iris forward and narrowing the space between the iris and the cornea. As this angle narrows, the fluid in the eye is blocked from the drainage system. So the fluid builds up, and eye pressure increases rapidly. Angle-closure Glaucoma can be chronic (progressing gradually) or acute (appearing suddenly). The acute form occurs when the iris completely blocks fluid drainage. When people with a narrow drainage angle have their pupils dilated, the angle may close and cause a sudden increase in eye pressure.
Primary open-angle Glaucoma: This is the most common form of Glaucoma. Damage to the optic nerve is slow and painless, but those affected can lose a large portion of vision before they notice any vision problems.
Secondary Glaucoma: This type of glaucoma forms as a result of trauma or disease. It may be caused by a variety of medical conditions, medications, physical injuries and eye abnormalities. Sometimes eye surgery can also lead to secondary Glaucoma.
Normal-tension or low-tension glaucoma: In this form of Glaucoma, eye pressure remains within the “normal” range, but the optic nerve is damaged nevertheless. The cause of this form of Glaucoma remains a mystery, but advances in Ophthalmology may provide us with answers soon.
Congenital Glaucoma. Children born with Glaucoma have a defect in the angle of their eye, which slows or prevents normal fluid drainage. Congenital Glaucoma usually presents with symptoms, such as cloudy eyes, excessive tearing, or sensitivity to light. Congenital Glaucoma can be hereditary.
The most common type of Glaucoma is primary open-angle Glaucoma. It has no signs or symptoms except for gradual vision loss. For that reason, you must schedule comprehensive eye examinations annually with Dr Boitumelo Khantsi Inc in Midrand, Johannesburg or Pretoria to monitor any changes to your eyes or vision. This is most important for people with family members with Glaucoma.
Acute-angle closure glaucoma, which is also known as narrow-angle Glaucoma, is a medical emergency. See your doctor immediately if you experience any of the following symptoms:
- severe eye pain
- redness in your eye
- sudden vision disturbances
- seeing coloured rings around lights
- sudden blurred vision
If you’ve experienced a loss of vision, please give Dr Boitumelo Khantsi in Midrand or Pretoria a call to schedule a comprehensive eye examination. The early treatment of Glaucoma could prevent additional vision loss and possibly save your eyesight, so you must see an Ophthalmologist as quickly as possible.