Glaucoma is one of the leading causes of blindness in the world. In the United States alone, over 2 million people are diagnosed with the eye disease. While there is no cure for glaucoma, vision loss can be prevented or slowed by early detection, medication, and/or glaucoma surgery.
What is Glaucoma?
Glaucoma is a blanket term for a group of eye diseases that damage the optic nerve, a bundle of nerves at the back of the eye. The optic nerve transmits visual signals to the brain, which results in the images we see. Optic nerve damage can lead to vision loss and blindness.
What Causes Glaucoma?
The anterior chamber, an area at the front of the eye, is responsible for the passage of clear fluid that flows in and out of the chamber to nourish nearby tissue. In a normal, healthy, eye, the fluid exits the anterior chamber at the open angle of the cornea and iris. Once the fluid reaches this area, it drains out of the eye through the open angle.
In people with open-angle glaucoma, the most common type of glaucoma, the fluid is too slow to drain out of the eye. This results in a buildup of pressure inside the eye, as most of the fluid remains inside. High eye pressure levels put strain on the optic nerve, which can result in vision loss or permanent blindness over time.
Other Types of Glaucoma
Angle-Closure / Narrow-Angle Glaucoma. This form of glaucoma is caused by fluid buildup behind the iris. The accumulation of fluid causes a sudden, dangerous spike in eye pressure. Narrow-angle glaucoma is considered a medical emergency — if the pressure is not reduced quickly enough, permanent vision loss can occur. Symptoms of narrow-angle glaucoma include severe pain, sensitivity to light, and nausea.
Low-Tension / Normal-Tension Glaucoma. This form of glaucoma is unique in that patients experience optic nerve damage and vision loss despite having normal eye pressure levels. People with normal-tension glaucoma may be sensitive to normal eye pressure levels, or reduced blood supply to the optic nerve may play a role. More research needs to be done in order to fully understand the disease.
Secondary Glaucoma. Secondary glaucoma is caused by another eye condition such as uveitis, a tumor, or trauma to the eye. Certain drugs such as steroids, and advanced cases of cataracts or diabetes can also cause secondary glaucoma.
Congenital Glaucoma. Congenital glaucoma is a rare, hereditary form of glaucoma. It occurs primarily in babies and children and is caused by a defect in the eye’s drainage system.
Glaucoma Risk Factors
People who have a family history of glaucoma, diabetics, African Americans over age 40, and Hispanic people over the age of 60 are all at increased risk of developing glaucoma. Thin corneas, chronic eye inflammation, and medications that affect eye pressure levels also increase the likelihood of developing glaucoma.
Symptoms of Glaucoma
Open-angle glaucoma is often referred to as the “silent thief of sight” — there are no noticeable symptoms until significant vision loss has occurred. The disease also develops slowly, so vision loss may not happen for many years. By the time a patient notices changes to their sight, glaucoma has likely advanced to a more serious stage.
Closed-angle glaucoma, also referred to as angle-closure glaucoma or narrow-angle glaucoma, does have symptoms. If you experience any of the following, contact emergency services immediately:
Severe eye pain
Glaucoma Treatment Options
Common glaucoma treatment methods include:
Eye Drops. Medicated eye drops are often prescribed to open-angle glaucoma patients to help stabilize eye pressure levels.
Pills. Oral medications are also available to control eye pressure in glaucoma patients.
Laser Trabeculoplasty. An eye surgeon uses laser energy to fix the drainage angle of the eye, so fluid drains properly and eye pressure is reduced. This procedure is performed on open-angle glaucoma patients.
Laser Iridotomy and Iridectomy. These procedures are treatments for closed-angle glaucoma. A laser is used to create a small hole in the iris, which helps fluid travel out of the drainage angle.
Trabeculectomy. A small incision is made in the white part of the eye to remove some of the mesh tissue and help excess fluid drain out.
Shunts. Aqueous shunts are tiny devices that are implanted in the eye to drain fluid and reduce eye pressure. The two most common shunts are the Ahmed Glaucoma Valve and the Baerveldt Glaucoma Implant.
iStent. The iStent is a device designed to treat glaucoma by reducing eye pressure in adults with mild or moderate open-angle glaucoma and cataracts. The iStent is the only device approved by the FDA to treat glaucoma in conjunction with cataract surgery.
The material contained on this site is for informational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health care provider.