Glaucoma is a disease caused by increased intraocular pressure (IOP) resulting either from a malformation or malfunction of the eye’s drainage structures. Left untreated, an elevated IOP causes irreversible damage the optic nerve and retinal fibers resulting in a progressive, permanent loss of vision. However, early detection and treatment can slow, or even halt the progression of the disease.
The eye constantly produces aqueous, the clear fluid that fills the anterior chamber (the space between the cornea and iris). The aqueous filters out of the anterior chamber through a complex drainage system. The delicate balance between the production and drainage of aqueous determines the eye’s intraocular pressure (IOP). Most people’s IOPs fall between 8 and 21. However, some eyes can tolerate higher pressures than others. That’s why it may be normal for one person to have a higher pressure than another.
Open angle (also called chronic open angle or primary open angle) is the most common type of glaucoma. With this type, even though the anterior structures of the eye appear normal, aqueous fluid builds within the anterior chamber, causing the IOP to become elevated. Left untreated, this may result in permanent damage of the optic nerve and retina. Eye drops are generally prescribed to lower the eye pressure. In some cases, surgery is performed if the IOP cannot be adequately controlled with medical therapy.
While patients with open angle glaucoma don’t typically have symptoms, those with angle closure glaucoma may experience severe eye pain accompanied by nausea, blurred vision, rainbows around lights, and a red eye. This problem is an emergency and should be treated by an ophthalmologist immediately. If left untreated, severe and permanent loss of vision will occur in a matter of days.
This type occurs as a result of another disease or problem within the eye such as: inflammation, trauma, previous surgery, diabetes, tumor, and certain medications. For this type, both the glaucoma and the underlying problem must be treated.
This is a rare type of glaucoma that is generally seen in infants. In most cases, surgery is required.