Types of Glaucoma

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.

Common types

Open Angle

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.  

Acute Angle Closure

Only about 10% of the population with glaucoma has this type.   Acute angle closure occurs because of an abnormality of the structures in the front of the eye.   In most of these cases, the space between the iris and cornea is more narrow than normal, leaving a smaller channel for the aqueous to pass through.   If the flow of aqueous becomes completely blocked, the IOP rises sharply, causing a sudden angle closure attack.

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.

Secondary Glaucoma

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.

Congenital

This is a rare type of glaucoma that is generally seen in infants. In most cases, surgery is required.