You may have heard of glaucoma but are you aware of how glaucoma affects your eye health and vision? Over 450,000 Canadians are affected by glaucoma and it is one of the leading causes of blindness. Known as ‘the silent thief of sight’, glaucoma can progress without symptoms or loss of vision during the early stages. Read further to learn more.
What is glaucoma?
Glaucoma is an eye disease characterized by a degeneration of the optic nerve.
The optic nerve, at the back of the eye, carries visual information to the brain. The amount and quality of this information decreases as the fibres that make up the optic nerve are damaged. This can cause vision loss.
What is the cause of glaucoma and who is affected?
The exact cause of glaucoma is not known.
If you have any of the following, then you may at an increased risk of developing glaucoma: elevated eye pressure, are over the age of 40, have a family history of glaucoma, have physical injury or surgery to the eye, cardiovascular conditions (such as high blood pressure, low blood pressure, heart conditions, etc), certain eye-related conditions (such as decreased optic nerve tissue, retinal detachment, eye tumour, eye inflammation, etc.), or diabetes.
What are the symptoms of glaucoma?
Glaucoma is often referred to as ‘the silent thief of sight’ because there are no symptoms in its early stages.
Depending on the type of glaucoma, symptoms may include blurry vision, eye redness, eye pain, light sensitivity, halos around lights, tearing, nausea, vomiting, headache, and rapid progression to vision loss.
The different types of glaucoma
- Primary open-angle glaucoma often develops painlessly and gradually with no early warning signs. This type of glaucoma accounts for approximately 90% of all glaucoma cases and can gradually destroy your vision without you knowing it.
- Angle-closure glaucoma may have symptoms such as nausea, eye pain, red eyes, blurred vision, and haloes around light. This condition can occur chronically or acutely.
- Normal-tension glaucoma is the term used for people who have developed glaucoma but have ‘normal’ eye pressure.
- Secondary glaucoma can form when an injury, infection, or tumor in or around the eye causing the pressure inside the eye to rise.
How does glaucoma affect my vision?
As glaucoma progresses, people may experience the loss of side vision or peripheral vision, eventually progressing to tunnel vision. Central vision loss takes place during the late stages of the disease. The loss of vision may interfere with daily tasks such as driving.
If left untreated, permanent vision loss can occur.
How is glaucoma detected?
As glaucoma can progress with or without symptoms, having a comprehensive eye exam is essential.
Early-stage glaucoma can be detected through a routine eye exam. Early detection and treatment are crucial in preventing the progression toward vision loss.
During an eye exam, the eyes’ internal pressure is measured using a painless procedure called tonometry. Our optometrists will also look directly inside the eye to inspect for any damage to the optic nerve and retinal layers. Your field of vision or peripheral vision will be measured; this can aid in diagnosing glaucoma.
Further imaging and testing may be conducted to measure functional vision loss and structural changes in the eye.
How is glaucoma treated?
Treatment will depend on the severity and progress of the disease. It cannot be cured, but rather controlled. Medication, generally in the form of eye drops, can be prescribed to reduce elevated eye pressure. Several surgical procedures are available to reduce eye pressure if treatment with medication is not enough.
Once vision is lost due to glaucoma, it cannot be restored. Since the disease can progress and change silently, routine eye exams and compliance with treatment are essential.
If you have further questions regarding glaucoma or your eye health, it is best to visit your optometrist.