Glaucoma

Q: What is glaucoma?

The term glaucoma describes a group of different eye disorders which, untreated, all lead to vision loss. Glaucoma is usually caused by an increased amount of the fluid inside the eye, which increases the amount of pressure on the eye. Elevated intraocular pressure damages the nerve that is responsible for sight (the optic nerve). Damage to the optic nerve causes vision loss, often so gradually that the patient is unaware of the disease until the eye has been badly damaged, and vision loss is permanent.

Q: Are there different types of glaucoma?

There are two main types of glaucoma - ‘open’ angle and ‘closed’ (or narrow) angle glaucoma. Often closed angle glaucoma is very painful and patients seek care right away. Other symptoms may include reddening in the eye, the sudden onset of blurred vision, visual changes in low light and a “halo” effect around lights. Open angle glaucoma is more often without symptoms, which is why it is called the “silent thief of sight”. This form of glaucoma is associated with gradual vision loss, including peripheral (side) vision and may result in tunnel vision in advances stages of disease.

Q: What causes glaucoma?

The cause is unknown. There are genetic factors and certain types are more common in certain ethnicities. In some cases, glaucoma can result from untreated cataracts, diabetes or as a later complication from old trauma to the eye. People older than 60 are at increased risk of glaucoma.

Q: Who is at risk?

Everyone theoretically is a risk for glaucoma, which is why routine eye check ups where the pressure in the eye is tested are so important. African Americans and Latin American people are prone to the most common form of glaucoma. The Asian population is prone to another type of glaucoma; persons of Scandinavian descent to another. One thing we do know is the incidence of glaucoma increases with age, so it’s important to have your eyes checked regularly, particularly as you get older. The American Academy of Ophthalmology recommends a comprehensive eye exam for all adults starting at age 40, and every three to five years after that if you don't have any glaucoma risk factors. After age 60, you should be screened every year. If you are African-American or have other risk factors for glaucoma, your doctor likely will recommend periodic eye exams starting between ages 20 and 39, and every one to two years after age 40. If you have a family history of glaucoma, have diabetes, or hypothyroidism, have experienced a traumatic eye injury or underwent eye surgery in the past, are nearsighted (far vision is blurry) or have used corticosteriods for prolonged periods, you may need to be examined more frequently or earlier. Please ask your doctor about your increased risk of developing glaucoma.

Q: How is glaucoma diagnosed?

The diagnosis involves repeat testing of the patient’s eye pressure, often utilizing sophisticated laser scanning of the optic nerve to assess subtle changes in the nerve tissue. Testing of the field of vision is also important to follow changes that can occur. More recently, superluminescent diode technology has been developed which shows great promise for becoming the best tool to diagnose and track disease changes. Your eye doctor should check for the following: intraocular pressure; optic nerve damage; field of vision and cornea thickness. Patients should be sure their provider has access to the latest technology, which is constantly changing, and knowledgeable in the small differences of all the glaucoma subtypes. As a reminder, ophthalmologists are medical doctors who specialize in diseases of the eye. Most ophthalmologists have completed a minimum of 12 years of education.

Q: How is glaucoma treated?

Often medicated eye drops are all that is needed, though sometimes a combination of drops is necessary as one drop alone may not lower the eye pressure enough. If a patient cannot instill the drops, or if they aren’t working to relieve the pressure in the eye, laser surgery can be performed. Sometimes conventional surgery is indicated, where an artificial drain in the eye is created. Occasionally, chemotherapy is applied at the time of surgery or after to modify the way the wound heals. Additionally, tiny tubes designed to drain fluid from the eye may be placed during drainage implant surgery. The drainage implants are another technological advance that shows great promise. As one of the few doctors in the area to use them for more than a year, I am proud to say that I was the first ophthalmologist in the Lehigh Valley to use this new technology. Can we prevent glaucoma? As a preventive measure, people should get regular eye exams, treat elevated eye pressure as soon as it is diagnosed, control your weight and blood pressure and wear eye protection during sports or in careers that work with tools or where there is risk of eye trauma.