Glaucoma is an eye disorder that causes damage to the optic nerve. Eye pressure is a major indicator of glaucoma, present in most forms of the disease, though it is not always present when glaucoma develops.
Abnormally high pressure is referred to as ocular hypertension. If this condition goes without treatment, glaucoma will first cause peripheral vision loss and eventually lead to blindness. Glaucoma is the second leading cause of blindness in the United States.
The most common form of glaucoma is open-angle glaucoma (OAG). The term “angle” in its name is referring to the drainage angle inside the eye that controls the outflow of the fluids (aqueous) that the eye produces. Glaucoma is “open-angle” when the aqueous is able to reach the drainage angle.
There are various forms of open angle glaucoma: Primary open-angle glaucoma, acute angle-closure glaucoma, normal-tension glaucoma, pigmentary glaucoma, secondary glaucoma and congenital glaucoma.
Primary open-angle glaucoma (POAG) is the most common form of glaucoma. It will reduce your peripheral vision without any other symptoms. This is extremely unfortunate because once you have realized there is an issue the damage is already done (and vision cannot be restored). Late diagnosis of open-angle glaucoma are often the direct result of the patient experiencing tunnel vision (peripheral vision loss) and realising something is wrong.
Acute angle-closure glaucoma is also referred to as narrow-angle glaucoma. This is when the drainage angle is blocked and the aqueous cannot reach it. This form of glaucoma has symptoms that develop suddenly, including:
If these symptoms do occur then medical attention is required immediately. This attack can last a few hours and keep coming back. Every time this occurs it can cause more vision loss each time.
Normal-Tension glaucoma is very much like primary open-angle glaucoma. The difference is that a person’s IOP (intraocular pressure) remains within normal range. The cause for this form is still unknown, but doctors believe it could be from poor blood flow to the optic nerve.
Pigmentary glaucoma is a rare form of glaucoma that is caused by clogging of the drainage angle by pigment that has broken off from the iris of the eye. Symptoms usually go unnoticed, although there could be some pain and blurred vision.
Secondary glaucoma is glaucoma that occurs after injuring the eye. This can occur from an eye infection, inflammation, a tumor or can be a side effect from a cataract.
Congenital glaucoma is the inherited form of glaucoma. It is present at birth. Children are born with narrow angles or a different defect in the drainage angle. This type of glaucoma is generally diagnosed during the child’s eye exam, as young children with congentical glaucoma cannot articulate what they are experiencing.
During routine eye exams the Optometrist will conduct a test that will measure the IOP of each eye. This test uses a tonometer to test the IOP. If the test comes back with an abnormally high IOP reading in the eye, our Optometrist will then outline a management program.
Glaucoma, while a serious vision-threatening disease, is successfully managed in most cases. Strict adherence to the treatment regimen is required in order to ensure vision is not lost.
Learn more about glaucoma management here.
