What is Glaucoma?
Glaucoma is a disease of the optic nerve, which is the part of the eye that carries the images we see to the brain. The optic nerve is made up of many nerve fibers. When damage to the optic nerve fibers occurs, blind spots develop. These blind spots usually go undetected until the optic nerve is significantly damaged. If the entire nerve is destroyed, blindness will occur.
Early detection and treatment are the keys to preventing optic nerve damage and blindness from glaucoma. This is one of the reasons yearly eye exams are so important.
Glaucoma is a leading cause of blindness in the United States, especially for older people. But loss of sight from glaucoma can often be prevented with early treatment.
Aqueous humor is the clear liquid that circulates inside the front portion of the eye. In a healthy eye, a small amount of this fluid is produced constantly while an equal amount flows out of the eye through a microscopic drainage system. This liquid is different from the tears on the outer surface of the eye.
If the drainage area for the aqueous humor (the drainage angles) is blocked, the excess fluid cannot flow out of the eye. Fluid pressure within the eye increases, pushing against the optic nerve and causes damage.
What are the Different Types of Glaucoma?
Chronic open angle glaucoma is the most common form of glaucoma in the United States. The risk of developing this type of glaucoma increases with age. With this type of glaucoma, the drainage angle of the eye becomes less efficient over time, and the pressure within the eye gradually increases, which can damage the optic nerve.
In its early stages, open angle glaucoma usually has no symptoms. As the optic nerve becomes damaged, blank spots start to appear in your field of vision. You typically would not notice these changes until the optic nerve has significant damage and these spots become large. If all the optic nerve fibers die, blindness will result.
Closed-angle glaucoma is another form of glaucoma. Some eyes are formed with the iris (the colored part of the eye) too close to the drainage angle. In these eyes, which are often small and farsighted, the iris can be pushed forward, blocking the drainage channel completely. Because the fluid can not exit the eye, pressure inside the eye builds up quickly and causes an acute closed-angle attack.
Symptoms may include:
- Blurred vision
- Severe eye pain
- Rainbow colored haloes around lights
- Nausea and vomiting
This is a true eye emergency. If you have any of these symptoms, call your ophthalmologist immediately. This type of glaucoma must be treated right away or blindness can result.
How is Glaucoma Treated?
Depending on the type, severity, and other eye conditions, treatment options may include eye drops, laser surgery or outpatient surgery.