Glaucoma.

Glaucoma is a group of diseases characterized by high pressure within the eye, damage to the optic nerve, and loss of peripheral vision. It is a leading cause of blindness in the United States. Although there is no cure, there are several treatment options, including medication, laser surgery, and traditional surgery, that can control the condition.
An Introduction to Glaucoma
Glaucoma is a group of diseases sharing certain features, commonly including high pressure within the eye (intraocular pressure), damage to the optic nerve, loss of peripheral (side) vision, and possibly blindness.

Nearly 3 million people have glaucoma. Approximately 80,000 Americans become blind each year because of it. The condition causes another 900,000 people to lose partial vision.

However, with early treatment, you may be able to protect your eyes against serious vision loss.

Understanding the Eye
The cornea is the clear outer covering of the eye. Separating it from the iris (the colored part) is the anterior chamber, a space filled and inflated by aqueous humor. This clear fluid (unrelated to the tears which bathe the outside surface of the cornea) starts in the ciliary body just behind the iris. It circulates in the anterior chamber, nourishing the eye's delicate tissue and keeping it from collapsing. To maintain equilibrium, the aqueous humor drains through a porous tissue in the angle in front of the iris, where it meets the cornea, called the trabecular meshwork.

If the aqueous humor cannot drain properly, either because the drainage canals become clogged (as in open angle glaucoma) or because the iris is pushing against the cornea (as in angle closure glaucoma), it backs up, putting pressure on the gel in the vitreous cavity at the center of the eye. Eventually, the building pressure affects the delicate optic nerve at the rear of the eye. Since the optic nerve transmits visual images to the brain, any damage to it reduces vision.

The optic nerve is a bundle of more than one million nerve fibers. It connects the retina to the brain. The retina is the light-sensitive tissue at the back of the eye. A healthy optic nerve is necessary for good vision.

Diagnosing glaucoma.

Your eye doctor has a variety of diagnostic tools which aid in determining whether or not you have glaucoma -- even before you have any symptoms. Let us explore these tools and what they do.

The Tonometer
The tonometer measures the pressure in your eye. Your doctor places a numbing eye drop in your eye. Then you sit at a slit-lamp, resting your chin and forehead on a support that keeps your head steady. The lamp, which lets your doctor see a magnified view of your eye, is moved forward until the tonometer, a plastic prism, barely touches the cornea to measure your IOP. The test is quick, easy and painless.

The Pachymeter
The pachymeter measures central corneal thickness (CCT). Like the tonometer, your doctor will first anesthetize your eyes. Then a small probe will be placed perpendicular to the central cornea.

CCT is an important measure and helps your doctor interpret your IOP levels. Some people with thin central corneal thickness will have pressures that are actually higher than when measured by tonometry. Likewise, those with thick CCT will have a true IOP that is lower than that measured. Measuring your central corneal thickness is also important since recent studies have found that thin CCT is a strong predictor of developing glaucoma in patients with high IOP.

Childhood glaucoma .....

.....is an unusual eye disease and significant cause of childhood blindness. It is caused by disease related abnormal increase in intraocular pressure. The multiple potential causes fall into one of two categories and may be primary or secondary to some other disease process. Primary congenital glaucoma results from abnormal development of the ocular drainage system. It occurs in about 1 out of 10,000 births in the United States and is the most common form of glaucoma in infants. Secondary glaucomas result from disorders of the body or eye and may or may not be genetic. Both types may be associated with other medical diseases.
Ten percent of primary congenital glaucomas are present at birth, and 80 percent are diagnosed during the first year of life. The pediatrician or family first notice eye signs of glaucoma including clouding and/or enlargement of the cornea. The elevated intraocular pressure (IOP) can cause the eyeball itself to enlarge and injury to the cornea. Important early symptoms of glaucoma in infants and children are poor vision, light sensitivity, tearing, and blinking.

Pediatric glaucoma is treated differently than adult glaucoma. Most patients require surgery and this is typically performed early. The aim of pediatric glaucoma surgery is to reduce IOP either by increasing the outflow of fluid from the eye or decrease the production of fluid within the eye. One operation for pediatric glaucoma is goniotomy. Its rate of success is associated with the age of the child at the time of diagnosis, the type and severity of the glaucoma, and the surgery technique. Other surgical options are trabeculectomy and glaucoma drainage tubes.

Approximately 80-90 percent of babies who receive prompt surgical treatment, long-term care, and monitoring of their visual development will do well, and may have normal or nearly normal vision for their lifetime. Sadly, primary congenital glaucoma results in blindness in 2 to 15 percent of childhood patients. When childhood glaucoma is not recognized and treated promptly more permanent visual loss will result.

Types of Glaucoma.

Secondary GlaucomaGlaucoma can occur as the result of an eye injury, inflammation, tumor or in advanced cases of cataract or diabetes. It can also be caused by certain drugs such as steroids. This form of glaucoma may be mild or severe. The type of treatment will depend on whether it is open angle or angle closure glaucoma.

Pseudoexfoliative Glaucoma
This form of secondary open angle glaucoma occurs when a flaky, dandruff-like material peels off the outer layer of the lens within the eye. The material collects in the angle between the cornea and iris and can clog the drainage system of the eye, causing eye pressure to rise.
Pseudoexfoliative Glaucoma is common in those of Scandinavian descent. Treatment usually includes medications or surgery.

Pigmentary GlaucomaA form of secondary open angle glaucoma, this occurs when the pigment granules in the back of the iris (the colored part of the eye) break into the clear fluid produced inside the eye. These tiny pigment granules flow toward the drainage canals in the eye and slowly clog them, causing eye pressure to rise. Treatment usually includes medications or surgery.