Blindness Without Warning

Glaucoma is a leading cause of blindness. While it is incurable, with proper prevention and intervention, it can be controlled, especially when caught in its early stages. This is key because everyone is at risk and there are often no warning signs to indicate that a problem—increased eye pressure—is present.

Dr. Herbert P. Fechter, Eye Physicians & Surgeons of Augusta, is a nationally-recognized specialist in the diagnosis and treatment of glaucoma. He explains that this group of eye diseases is made up of several categories.

Primary open angle is the most common form of glaucoma, he says. In this form, eye pressure increases because, while the entrance to the eye’s drain is open, the drain itself is clogged, preventing fluid (not to be mistaken with tears, which are outside of the eye) from flowing and hence increasing pressure. “The drain is located between the cornea and the iris, but we cannot see it,” he says. “Fluid is normally made behind the iris in the ciliary body, goes around the iris and out of the drain. In glaucoma patients, the fluid cannot get out and the eye pressure increases. That causes damage to the optic nerve in the back of the eye. We do not know the cause of primary open angle glaucoma.”

Angle closure glaucoma is the second form of glaucoma, in which the iris comes forward and blocks the drain, says Dr. Fechter. “This form of glaucoma is usually found in patients who are very far-sighted and born with a very narrow angle structure,” he says. “Certain medications, such as antihistamines, sulfa drugs and cold medicines, can make a patient more susceptible. Therefore, it is very important to read the warning labels and consult a physician if you are at risk.”

Two other less-common forms of glaucoma are pseudoexfoliation and pigmentary glaucoma, which is found in young, nearsighted (myopic) males. Normal tension glaucoma occurs when eye pressure is normal. It is due to inadequate blood supply to the optic nerve, says Dr. Fechter. “These patients also experience cold fingers and toes and migraine headaches. These things are triggered by inadequate blood supply, and even regular glaucoma can be worsened by poor blood supply.”

Again, there is no known cause for this, but some things, like high blood pressure and diabetes, can be risk factors. “There is a lot of research in glaucoma treatment and diagnosis, but it is still a wide-open field. We have rudimentary treatments and we do not know all of the causes,” he says.

Primary open angle glaucoma, the most common form, has no symptoms. It progresses slowly over decades, says Dr. Fechter, and “unfortunately, many people are only diagnosed at 55 or 60, and by then a lot of damage has occurred that could have been prevented had they been diagnosed earlier.” This is why it is important to have routine screenings and checking of eye pressure by an optometrist or ophthalmologist.

With angle closure glaucoma, eye pressure increases quickly, says Dr. Fechter, and is accompanied by severe pain, nausea and blurry vision. Damage is immediate and visible, but vision can be saved via a laser procedure called peripheral iridotomy, in which a hole is made in the iris to allow eye fluid to drain properly.

Testing is key to preventing glaucoma. “A healthy adult should be tested every two years with an eye exam,” says Dr. Fechter. “Three things go into diagnosis. The first is high interocular pressure. The second is abnormal appearance of the optic nerve. Third, if either of these two are suspicious, further testing will be done and a visual field performed to see if the patient has lost peripheral vision—the vision around the nose—because those nerve fibers come out on the top and bottom of the optic nerve and are most susceptible to elevated pressure.”

Again, glaucoma is incurable, but it can be treated through medication, laser, surgery or a combination of the above, depending on severity and level of eye pressure.

“The usual standard of care is to start with medication, a prostaglandin or a beta blocker, once a day, generally at bedtime,” says Dr. Fechter. The primary issue with medication treatment is compliance. “Patients have to follow the regimen,” he says. “Medication is expensive, treatment is not easy, following the regimen is difficult and there is no feeling of satisfaction that eye pressure is lower.” Studies show that compliance is poor. When patients are on a medicine regimen and using drops, they may do this before they come to the doctor, so their pressure appears low, but if they don’t follow the regimen daily, their glaucoma worsens and they need laser therapy or surgical incision to get their eye pressure down.

“With laser therapy, the laser is placed on the surface of the drain and we believe that it causes the white blood cells to work harder to clean out the drain. Some studies show that this is equally effective to medication, but many patients are frightened of having a laser in their eyes. There is 50 percent recidivism with laser therapy. Medications are life long, but the glaucoma can worsen. Sometimes the laser is not enough and the patient needs medication as well,” says Dr. Fechter.

Patients have two surgical options, according to Dr. Fechter. The first, trabeculectomy, requires creating a blister, or bleb, on top of the eye, under the lid. “An incision is made around the cornea,” he says. “We pull the skin back and cut a hole in the eye at ‘12 o’clock’ through the edge of the cornea between the sclera and cornea. Fluid flows to the blister and percolates through the blister wall to the tear film or into the bloodstream. At three years, this procedure is 70 percent effective.”

The other option is a glaucoma drainage device, which requires insertion of a silicone plate. Once again, a hole is cut at the top of the eye. “A very small tube is placed into the eye in the same region where that hole is made,” says Dr. Fechter. “It runs to a silicone plate the size of a dime, attached to a globe 10 millimeters from the cornea, behind the eyelid, at the top. Fluid flows through the tube to the area around the plate, to the tear film or into the bloodstream. The plate is permanent and prevents scarring. It is rarely felt by the patient and is covered by the skin of the eye. At three years, the success rate of this procedure is 85 percent.”

While everyone is at risk for glaucoma, some groups are at higher risk, particularly older African-Americans and Hispanics and individuals who have a family member with glaucoma. In these cases, Dr. Fechter recommends that eye-pressure testing begin by age 30 for early intervention. “Family history is very important,” he says. “You have a much higher risk of contracting glaucoma if someone in your family has it.”

A glaucoma screening should be included with each eye exam. For uninsured patients or individuals with low income, health fairs often offer screenings at no charge. “I worked with Friends of the Congressional Glaucoma Caucus in which a van would come to health fairs with screening machines, pressure recording devices and charts,” says Dr. Fechter. “We would see about 80 patients in the morning and find that five to 10 of them were at risk for glaucoma. With routine eye exams and frequent follow-ups of at-risk patients, as well as compliance with a medical regimen, if needed, a lot of unnecessary blindness can be prevented.”