Glaucoma is a disease of the optic nerve. Glaucoma is caused by the drainage passage inside the eye being mechanically blocked or not functioning correctly. This causes a build up of clear fluid called aqueous humor which subsequently causes a rise in intraocular pressure. This pressure can damage the optic nerve over time and cause a loss of peripheral vision and eventually central vision. Even when the intraocular pressure is not above average, it may still be high enough to cause optic nerve damage. The average intraocular pressure in adults is 15 mmHg, but normal intraocular pressure is different for each individual. The higher the intraocular pressure, the more likely is the possibility of progressive glaucoma damage.
Unfortunately, the common kinds of glaucoma have no early symptoms. Once the loss of vision is noticed by a patient, the damage is usually very severe and irreversible. Elevated pressure cannot be felt unless the pressure is very high. In order to preserve vision, glaucoma must be diagnosed early. Glaucoma is a lifelong disease but can be controlled.
It is estimated that more than 2 million Americans have some type of glaucoma and half of them do not know it. With rare exceptions, glaucoma has no symptoms. There is no pain or discomfort to the eye, only a gradual loss of vision. This change may occur over weeks, months, or even years before you realize you are losing vision. But take heart, Eye Center of Texas utilizes several sophisticated instruments that can detect glaucoma before symptoms even occur.
In most cases, glaucoma is caused by elevated pressure inside the eye. Yet pressure is not the only risk factor. There are many patients with normal pressures who still have the disease. That’s why it’s important to visit the Eye Center of Texas on a regular basis to determine if you have glaucoma. Aqueous humor flows out of the eye through the Trabecular Meshwork (TM), near the edge of the iris. If the TM is blocked, restricting drainage, the pressure inside the eye increases. This elevated eye pressure results in damage to the optic nerve and vision loss occur.
Measurement of eye pressure, optic nerve health and peripheral vision testing all provide valuable information in establishing a diagnosis of glaucoma. The Eye Center of Texas uses an Ocular Coherence Tomographer (OCT), one of the most sensitive devices to measure the thickness of the retinal nerve fiber layer and the size of the cup (depression) of the optic nerve, which is the tissue directly affected by glaucoma. The screening is comfortable and convenient. A computer maps the nerve fibers and instantly compares them to a database of normal readings. Thin nerve fiber readings indicate the onset of glaucoma and the need for further testing.
The Dr. Wade and Mayo at the Eye Center of Texas may recommend medication for treatment. This is usually in the form of eye drops. Medication won’t cure the disease but can keep it under control. For patients who don’t want to use drops daily due to side effects, expense or the hassle of using a medication daily, a laser is an option. The laser (SLT) is a 5-minute outpatient procedure that is painless and is as effective as drops. 80% of people respond to laser and the average duration of effect is 3-5 years. With the SLT laser treatment can be repeated if the effect wears off with time.
Drs. Wade and Mayo at the Eye Center of Texas have successfully performed thousands of these procedures. We recommend you click this link for more information on treatment options http://www.glaucomaslt.com/wt/page/glaucoma_treatment and http://www.glaucomaslt.com/wt/page/faqs. In patients who don’t respond to laser or medication, surgery is recommended to help preserve vision. The surgery is an outpatient procedure that takes 20-30 minutes to perform under light IV sedation.
Filtration surgery is done when medication and/or laser eye surgery is unsuccessful at controlling the intraocular pressure. During this procedure, a new drainage channel is created to allow aqueous humor to drain from the eye. It is important to understand these are all treatments for glaucoma but there is no cure. It is very important each patient continues to see their eye doctor for pressure checks every 3-6 months depending on the severity of glaucoma and the pressure response to treatment.