Light enters the eye through the cornea. The iris is the part of the eye that expands and shrinks in order to change the size of the pupil so that the correct amount of light enters the eye. The light is focused on the back part of the eye, called the retina. The retina has nerve fibers and transmits visual data to the brain by way of electrical signals along the optic nerve. The front part of the eye has a clear fluid that exerts an internal pressure. There are risks associated with this pressure becoming too high, as it can cause damage to the optic nerve.
Angle-Closure Glaucoma
Angle-closure glaucoma is associated with a sudden increase in eye pressure. Normally, there is some drainage of the fluid from the front part of the eye. When this drainage is completely blocked, eye pressure can increase suddenly. There can be severe pain in the eye and eyebrow and nausea as a result. Also, the eye can redden and vision can become blurred. Headaches may develop. Halos can be seen around lights, and there can be sensitivity to lights, even lights that have low intensities. This condition is considered a medical emergency, and medical attention should be sought. As with all forms of glaucoma, loss of vision is a risk.
Open-Angle Glaucoma
A slowly increasing eye pressure will gradually increase the pressure on the optic nerve. This pressure can damage the nerve and eventually lead to loss of vision. There can be a gradual loss of peripheral vision. There will be a visual effect of looking through a tunnel with objects to the sides not being visible. The loss of peripheral vision can progress until blindness results.
Treatment
High eye pressure can be treated. These treatments reduce the risks associated with high eye pressure. There are medicines that help fluid drain from the eye. Other medicines cause the eye to produce less fluid. A procedure called laser trabeculoplasty will help fluid drain from the eye and reduce the pressure. Also, a conventional surgical procedure can introduce a new way from fluid to drain from the eye, helping to reduce the pressure.
