The Silent Thief of Sight
Glaucoma is one of the leading causes of blindness. It often has no symptoms – especially in its early stages – earning the descriptor, “the silent thief of sight”.
Let’s learn more.
Glaucoma is a condition characterized by damage to the delicate fibers that make up the optic nerve of the eye. Left untreated, it can result in permanent loss of vision. Eye pressure plays a major role in damaging the delicate nerve fibers of the optic nerve. In addition to the normal age-related loss of fibers, there is accelerated fiber damage when glaucoma is present. When a significant number of nerve fibers are damaged, blind spots develop in the field of vision. Most people don’t notice these blind areas until much of the damage has already occurred and some vision has been permanently lost. This is the reason why glaucoma is often called “the silent thief of sight”.
The exact cause of glaucoma is not known. But the technical answer is that the passages that normally allow fluid within your eye to drain become clogged or blocked. Fluid then builds up and increases pressure on the optic nerve. The nerve fibers and blood vessels in the optic nerve are easily damaged by this pressure, resulting in vision loss.
Worldwide, glaucoma is the second-leading cause of irreversible blindness. Within the United States, over 3 million people are estimated to have glaucoma. Unfortunately, about half of the people who have glaucoma don’t even know it! This is because the intraocular pressure can build up and destroy sight without causing obvious symptoms. For this reason, awareness and early detection of glaucoma are extremely important. Glaucoma can usually be successfully treated when diagnosed early.
The presence or risk of glaucoma can be easily determined by a comprehensive eye exam with specialized testing.
At Eye Medical Clinic, our patients are routinely checked for glaucoma and other eye diseases. We encourage everyone to have an annual comprehensive eye exam that includes a glaucoma screening. Additional testing is available for those patients in whom glaucoma is suspected.
Glaucoma does appear to run in families and the tendency for developing glaucoma may be inherited. But just because someone in your family has glaucoma does not mean that you will necessarily develop the disease. High IOP is the most important risk factor for developing glaucoma.
Glaucoma appears most frequently in people over the age of 40. Additionally, glaucoma occurs more frequently in African Americans than in Caucasians.
While everyone is at risk for glaucoma, certain people are at a much higher risk and need to be checked more frequently by their eye doctor. The major risk factors for glaucoma include age over 40 years, family history of glaucoma, diabetes, African American ancestry, nearsightedness, farsightedness, history of injury to the eye, certain infections and tumors in and around the eye, and certain medications (especially steroids).
In most cases, glaucoma does not have any symptoms other than slow vision loss. For this reason, a glaucoma test is an essential part of a routine eye exam. Glaucoma tests are designed to test your eyes for increased eye pressure, one of the key signs of the disease. However, only a comprehensive eye exam can reveal whether or not you have glaucoma.
One common glaucoma test administered at Eye Medical Clinic involves using a special device to measure eye pressure. While elevated eye pressure is a key component of the disease, about 30-40% people with field loss from glaucoma do not have elevated eye pressures. For reasons that are not clear, Asian populations are especially susceptible to Normal Tension Glaucoma. Therefore, the only reliable way to detect glaucoma is to have a detailed, comprehensive eye exam that includes dilation of the pupils.
There are actually several types of glaucoma, but the two main types are open-angle and angle-closure glaucoma. These are marked by an increased IOP, or pressure inside the eye. Open-angle glaucoma is the most common form of glaucoma, accounting for at least 90% of all glaucoma cases, according to the Glaucoma Research Foundation.
While there is no cure for glaucoma at this time, it can be controlled and stabilized by maintaining the eye pressure in a safe range. Contrary to previous assumptions, there is no magic or standard cutoff value for safe eye pressure. Instead, it is an individualized number or range, which depends on the severity of glaucoma damage, age and corneal thickness as well as a host of other factors. All current glaucoma treatments are directed toward lowering the eye pressure.
At Eye Medical Clinic, each glaucoma patient’s treatment plan will vary depending on the type of glaucoma diagnosed, the degree to which the glaucoma has progressed, underlying risk factors and many other variables.