What is Glaucoma?
Glaucoma is a disease of the optic nerve. The optic nerve carries the vision signals from the retina to the brain. It is made up of many nerve fibers, just like a telephone cable is made up of phone wires. Glaucoma means the optic nerve is losing nerve fibers. If enough nerve fibers are lost, blind spots develop. It is usually a subtle process and people are often unaware of these blind spots until significant vision loss has occurred. If this condition is diagnosed early, it can be treated and blindness prevented.
What Causes Glaucoma
The eye is a closed system which makes and drains its own fluid. This clear fluid occupies the front part of the eye and carries nutrients and oxygen to the cells. The amount of fluid produced and drained is usually in balance and maintain a healthy level of pressure inside the eye. If the drain fails to work as well as it should, the pressure increases and the optic nerve becomes damaged by losing nerve fibers. Although most optic nerves can tolerate a normal pressure, some are more delicate and can lose vision at what would be considered normal levels of pressure.
Types of Glaucoma
- Open-angle glaucoma is the most common type. Although the anatomy appears normal, the drain meshwork does not function as it should. Since the fluid production is constant, if the drain doesn’t work properly the pressure inside the eye increases. This increase in pressure causes damage to the nerve and vision loss results. It is usually a slow process much like your sink drain becoming slowly plugged so it seems to drain slower and slower. Once the vision is lost, it’s gone. Treatment is necessary to prevent further vision loss.
- Narrow-angle or angle-closure glaucoma is a problem of anatomy. If the iris is positioned too close to the inside of the cornea, the iris can physically block fluid access to the drain. This causes a sudden build-up of pressure in the eye much like putting a stopper in your sink drain causes the sink to rapidly fill.
Unfortunately, there are usually no early symptoms of chronic open-angle glaucoma. That is why it is often referred to as the ‘silent thief of sight.’ You may not detect a change in your vision until you have significant, permanent vision loss. This is another reason why regular eye exams are so important; eye exams will detect glaucoma so you can begin treatment immediately.
In contrast, an acute glaucoma attack is an eye emergency. It needs to be treated without delay or blindness can result. Symptoms may include:
- blurred vision
- Eye pain
- halos around lights like looking through a steamy shower door
- Nausea and vomiting
If you are noticing several of these changes in your vision you should see an ophthalmologist or go to your emergency room. Dr. Stephen H. Johnson can provide an examination for open-angle or narrow-angle glaucoma in Newport Beach and recommend glaucoma treatment options for you.