Glaucoma, the leading cause of preventable blindness in the United States, affects approximately 2.2 million Americans age 40 and older. Known as the “silent thief” of sight, it can quietly steal your vision by damaging the optic nerve and causing vision, often without warning. In fact, more than half of the people who have glaucoma do not even realize that they have the disease.
Like a cable wire, the optic nerve is responsible for carrying the images we see to the brain. The optic nerve can be damaged when the pressure within the eye increases, usually due to a build-up of a aqueous fluid within the eye. Blind spots develop within the field of vision. These blind spots usually go undetected by the person who has glaucoma, until the optic nerve has suffered significant damage and some peripheral and central vision has been lost. The damage caused by untreated glaucoma can result in irreversible blindness. A visual field evaluation can detect glaucoma damage in its very early stages—another very good reason to have regular eye exams.
Types of Glaucoma
Chronic open-angle glaucoma
In the most common type of glaucoma, the drainage “angle” (where fluids in the eye drain) is open but working less efficiently, much like an air filter that gathers dust over time and eventually becomes too clogged to work properly. The inability to drain causes pressure within the eye to rise, and results in a gradual loss of side vision.
Acute angle-closure glaucoma
This type of glaucoma occurs when the drainage angle is completely blocked, often by the eye’s iris. This prevents any fluid from draining from the eye. Pressure within the eye suddenly and dramatically rises, causing blurred vision, headaches, severe eye pain, and the appearance of halos around lights.
Chronic angle-closure glaucoma
This more gradual and painless type of angle closure occurs most frequently in people of African or Asian descent.
This type of glaucoma, which progresses in much the same way as chronic open-angle glaucoma, occurs when scar tissue blocks the drainage angle. The first symptom is loss of side vision.
This birth defect affects the drainage angle and must be treated shortly after birth to prevent blindness. Symptoms include enlarged eyes, a cloudy cornea, light sensitivity, and excessive tearing.
Glaucoma Treatment Options
Have you been told by your eye doctor that you have high intraocular pressure and might have glaucoma? Don’t be discouraged—our doctors specialize in helping people who have glaucoma. In fact, our board certified surgeon leads the area in advanced procedures that may reduce your dependency on glaucoma medications. He or one of our optometrists may recommend one or more of these treatment options:
- Medication: Glaucoma is usually treated with daily eye drops that decrease eye pressure either by slowing the amount of fluid produced within the eye or by improving drainage of that fluid.
- Surgery: Options vary based on patient needs. See below.
Dr. Fischer currently offers several surgical glaucoma treatments to lower pressure within the eye:
Selective Laser Trabeculoplasty (SLT)
This non-invasive, low-energy procedure heats an area of the eye to help open the drainage system by targeting cells in the trabecular mesh system of the eye.
This is a more involved procedure for individuals who have already had cataract surgery. Dr. Fischer lasers the cilliary muscle where the aqueous fluid is produced to decrease flow.
This procedure is more commonly used after other treatments have not been successful in lowering pressure. It involves creating a tiny passageway from the inside to the outside of the eye to help fluid drain better from areas where it is not currently draining.
Endoscopic Cyclophotocoagulation (ECP)
ECP is a technique that reduces the amount of fluid produced in the eye and thus lowers pressure within the eye (intraocular pressure or IOP). ECP is often performed at the same time as cataract surgery for patients who suffer from both cataracts and glaucoma. Recent studies show that patients who undergo the combined ECP/cataract surgery need fewer glaucoma medications over the long term.The result is a lower, healthier pressure within the eye. Many patients who undergo ECP will sometimes no longer need eyedrops or other glaucoma medications after treatment.
An innovative approach to treating glaucoma for those who have both cataract and glaucoma is the iStent®. iStent® is the smallest medical device ever approved by the FDA, and is placed in the eye during cataract surgery. It is so small, you won’t be able to see or feel it after surgery, but it works continuously to help reduce eye pressure by improving outflow of fluid from the eyes. After implantation, many patients are able to control their eye pressure. In a U.S. clinical trial, iStent patients who achieved a target pressure of < 21 were more likely not to need their medications than patients with cataract surgery only.