Glaucoma is a silent vision killer. As glaucoma progresses, peripheral vision slowly deteriorates with no symptoms or pain. This is why it is so important to follow through on regular scheduled eye examinations.
There are two broad categories of glaucoma, open-angle glaucoma and angle-closure glaucoma. Both forms demonstrate vision loss due to optic nerve damage. The optic nerve is the structure that allows the visual signal to be transferred from the retina to the brain where the brain can interpret the information as sight and vision.
A special fluid called aqueous humor continually circulates through the anterior portion of the eye. This fluid is constantly being produced and eliminated at a constant rate. If the fluid is produced faster than it is eliminated, or the fluid is delayed in being eliminated, the intra-ocular pressure inside the eye (IOP) will increase. Just because the IOP is higher, however, doesn’t mean that a person has glaucoma or that glaucoma will develop. The “air-puff” test is one way to measure IOP, a high reading is a risk factor for developing glaucoma, but it is just one of the many risk factors considered.
Most glaucoma medications and glaucoma related surgeries are aimed at lowering IOP. The pressure inside the eye is said to be diurnal, meaning that it fluctuates between a high and low point and the key is to keep the “high” value in the lower range of normal.
Generally speaking, meaning there are many variables, visual loss begins in the peripheral vision of one eye. The brain overlaps images from the two eyes in order to appreciate depth perception. Because of this, if vision loss develops in one particular portion of the visual field of one eye, the brain will blend in the vision from the other eye and most often the vision loss will go unnoticed.
Eye care professionals use a visual field test to determine if there is visual field loss due to glaucoma. The test is performed with one eye only at a time, this ensures there is no overlap from the other eye.
Slowing vision loss related to glaucoma can only be accomplished with early detection and appropriate treatment. Maintaining annul eye exams is crucial in order to prevent vision loss related to glaucoma.