January is Glaucoma Awareness Month, the number 2 cause of blindness. Our guest blogger Meredith Rogers from geriatricnursing.org has some facts about glaucoma that you should know. Read below:
Key Facts You Should Know About Glaucoma
Glaucoma refers to is an eye disease that develops from a buildup of pressure that damages the optic nerve. Glaucoma, if untreated can create vision loss and irreversible blindness.
In functioning and healthy eyes, there is a constant creation and drainage of fluid. This clear fluid covers the front of the eye and is known as the aqueous humor. The aqueous humor nourishes and protects the front of the eye. The aqueous humor flows through the different parts of the eye, through the pupil, and then is drained through channels known as the trabecular meshwork. The trabecular meshwork sits at an angle called the eye’s drainage angle.
When the ciliary body of the eye produces too much of the aqueous humor fluid, or when the trabecular meshwork becomes clogged, strained or blocked, the pressure in the eye, the intraocular pressure, becomes too high. This can result in damage to the optic nerve. This damage is known as glaucoma.
There are two major types of glaucoma. The first is called Primary Open-Angle Glaucoma. Primary Open Angle Glaucoma is the most common form of the disease. It refers to a gradual accumulation of the intraocular pressure. The eye’s drainage system isn’t completely stopped up, but it doesn’t drain as well as it should. The pressure builds slowly, and damage to the optic nerve isn’t noticeable at first. This accounts for the nickname for glaucoma, “the sneak thief of sight.” The pressure is painless at first, and the person suffering from this type of glaucoma won’t notice vision issues at first.
The second major type of glaucoma is known as Closed Angle Glaucoma or Narrow Angle Glaucoma. When the eye’s iris is close to the drainage angle of their eyes, the iris itself can block the drainage of the aqueous humor fluid. Eventually, the iris completely covers the drainage angle and eye pressure builds up suddenly and dramatically. Glaucoma of this type is known as an acute attack and can cause eye damage and blindness. Closed angle glaucoma that develops slowly over time is known as chronic angle-closure glaucoma.
There are a few other, less common types of glaucoma as well. Congenital glaucoma occurs during development before a person is born. With congenital glaucoma, babies are born with an incorrect angle in their eye that can interfere with fluid drainage. Babies are born with light sensitivity, eye cloudiness, and overly-watery eyes. If completed in time, surgery can save the baby’s vision.
Secondary glaucomas are glaucomas that happen as a symptom, side effect, or complication of another medical issue or condition. High blood pressure, diabetes, cataracts, tumors, inflammation and irritation, injury or other eye conditions can be causes of secondary glaucoma. Other glaucomas can include pigmentary glaucoma, where glaucoma is derived from the eye’s iris shedding and blocking the drainage of fluid or pseudoexfoliation glaucoma where extra tissues or materials are made by the eye and then, as they shed off the eye’s surface or internal structures, blocks the drainage of fluid.
If your eye doctor suspects you may have glaucoma, they will put you through rigorous testing to confirm their diagnosis. They’ll first dilate your eyes then give you an examination which usually includes testing your ability to see at different distances, known as a visual acuity test. They’ll give you a visual field test which measures your peripheral vision abilities. After dilating your eyes, they’ll give you a dilated-eye exam in which they look at your eye through magnification to see if there’s any visual damage to your optic nerve, retina, or drainage. They’ll use a Tonometer to measure your eye’s internal pressure, since many forms of glaucoma come with increased pressure in the eye. Finally, they’ll measure the thickness of your cornea, known as Pachymetry. Pachymetry uses ultrasonic waves to measure your cornea’s thickness.
If your tests for glaucoma lead to a positive diagnosis, your doctor will then talk to you about a treatment plan. Open angle glaucoma, if found in the early stages, can be slowed down with treatment, so having regular vision checks is an important part to maintaining your vision.
Glaucoma, depending on the type, can be a progressive disease or an abrupt one. Having your vision regularly checked and telling you doctor about any changes in your sight can be the difference between losing your ability to see or keeping it.