Glaucoma, commonly referred to as the"sneak thief of sight," steals the vision of thousands of people every year. Glaucoma is a leading cause of blindness in people over 40.
The sad thing is it doesn't have to happen. If glaucoma is diagnosed early, before it has done major damage, it can be treated and, in most cases, the vision loss stopped through medications and/or surgery. Damage that has already taken place, however, cannot be reversed. That's why early detection is so important in treating glaucoma.
Although there are different types of glaucoma, all of which involve a build-up of pressure inside the eye, the two most common are chronic and acute. In both forms abnormal pressure cause damage to the optic nerve, the bundle of fibers that carry sight messages to the brain. Left untreated, the result is impaired vision and blindness.
Acute glaucoma appears suddenly with severe pain and sharply reduced vision, and often with nausea and vomiting. An urgent visit is usually required to relieve the pressure and prevent further damage to the eye.
Open Angle Glaucoma
Chronic glaucoma, by far the most common form, is painless and develops slowly without symptoms. Most people who have it are unaware that they are being robbed of their eyesight because the vision loss is so gradual. There are no warning signs, only irreversible damage to the optic nerve by the time vision problems are noticed.
The onset of glaucoma usually occurs at age 35 or older. Two out of every 100 people in this age group have vision threatened by this disease.
There are many tests available to assist in diagnosing glaucoma, or monitoring for possible progression of the condition. Our office employs the latest glaucoma technology available.
Visual Field Test - This test uses white flashes of light to evaluate the peripheral vision in each eye. A person looks into a bowl-shaped surface and stares at a central target point. A computer-driven program flashes small lights at different locations within the bowl's surface, and the person being tested presses a button when he or she sees the small lights in their periphery. This allows detection of subtle changes to the vision of which you may not be aware and allows for monitoring of changes over time.
Digital Photographs of the Optic Nerves - This provides three-dimensional photographs of the surface of the optic nerves to look for signs of damage from glaucoma.
Ocular Blood Flow Analyzer - Our office utilizes the Paradigm-Dicon Pulsatile Ocular Blood Flow Analyzer (OBFA). The OBFA is also a quick, painless test that measures what level of eye pressure the blood vessels serving the optic nerve can withstand before becoming weak and causing decreased blood flow to the nerve. This can be especially helpful in diagnosing patients who have"normal tension glaucoma". This is a difficult type of glaucoma to diagnose where vision is lost in eyes that have eye pressures within what is generally considered to be the normal range.
Pachymetry - A quick, painless, test that measures the thickness of the cornea, which has been found to affect the accurate measurement of eye pressure.
Nerve Fiber Analysis - The GDx VCC Nerve Fiber Analyzer uses scanning laser technology to provide a computer generated three-dimensional map of the surface of the optic nerve to look for signs of damage from glaucoma. The test is comfortable, does not require eye drops or pupil dilation and provides results in minutes. Optic nerve fiber damage can be measured up to six years before it can be detected with visual fields.
These instruments as well as many others in our office allow us to manage glaucoma with the most state of the art technology in the industry.
Glaucoma is sometimes controlled with eye drops, given 1 to 3 times a day, or by pills. These medications reduce the pressure in the eye by either assisting the flow of fluid out of the eye or by decreasing the flow into the eye. Taking the medications will probably be a lifetime routine. In other cases, a laser procedure is able to lower the pressure, sometimes delaying or preventing the need for medications.
Laser Treatment for Glaucoma
Selective Laser Trabeculoplasty (SLT): By using advanced lasers focused onto the filtering drain of the eye, your ophthalmologist may be able to cause a reduction in eye pressure. Laser surgery for chronic glaucoma is typically painless and usually takes only 5 to 10 minutes to complete. Prior to the procedure, eye drops will be given to prepare the eye for treatment. The laser applications are applied through a special microscope similar to the ones used for eye exams. A lens is placed over the eye to direct the light to the filtering meshwork.
SLT typically lowers the pressure in the eye about 85% of the time. The results of the SLT tend to decrease over time, but this procedure can be repeated, often with excellent results. While it may take a few weeks to see the full pressure-lowering effect of this procedure, during which time you may have to continue taking your medications, many patients are eventually able to discontinue some of their medications. Eye pressure may drop as quickly as a day after the procedure. In certain people with advanced glaucoma for whom SLT does not sufficiently reduce eye pressure, glaucoma surgery may be necessary.
Laser Peripheral Iridotomy (LPI): For patients with narrow-angle, or acute glaucoma. A small hole is made in the iris so that the fluid inside the eye can properly circulate and encourage fluid drainage to lower the eye pressure. Before the laser treatment, anesthetic eye drops will be applied to numb the eye. A lens lubricated with a gel-like substance will then be placed on the eye to help keep your eyelids from blinking and to allow the doctor to focus the laser onto the iris.
The only defense against chronic glaucoma is early screening as part of regular eye examinations. Glaucoma is dangerous. It can steal your vision without warning. If you're over 40 and have not had a glaucoma check within the past three years, we suggest you get one soon.