Ask an Expert about Glaucoma

Elevated eye pressure increases the risk of developing glaucoma; however, the disease can occur in people with normal or even lower-than-normal eye pressure. It is optic nerve damage that can lead to vision loss and possible blindness. In many people, fluid pressure increases inside the eye and damages the optic nerve (the bundle of nerve fibers that carries information from the eye to the brain). In addition, individuals with higher-than-normal eye pressure do not always develop the symptoms of glaucoma.

Since normal-tension glaucoma does not involve high eye pressure, it is diagnosed by observing the optic nerve for any signs of damage. The eye doctor will use an ophthalmoscope to look through the pupil at the shape and color of the optic nerve. In addition, a visual field test can help determine if there is any loss of peripheral vision. The risk factors for developing normal-tension glaucoma include a family history of glaucoma, low eye pressure, and cardiovascular disease. Ongoing research is aimed at determining all of the factors that contribute to the optic nerve damage. For example, scientists believe the optic nerve may be affected by blood flow in the eye. Researchers are also investigating susceptibility and genetic factors.

Laser surgery can aid in controlling the symptoms of glaucoma, but no treatments currently available will cure the disease. Several forms of laser surgery can help fluid drain from the eye or decrease the amount of fluid produced. These techniques support the maintenance of normal eye pressure and minimize the risk of further damage to the optic nerve.

No, but there are sight-saving treatments. So the sooner a person is diagnosed, the more vision can be preserved.

The most common treatments for glaucoma are eye drops and, rarely, pills. There are a number of different categories of eye drops, but all are used to either decrease the amount of fluid (aqueous humor) in the eye or improve its outward flow. Sometimes doctors will prescribe a combination of eye drops. People using these medications should be aware of their purpose and potential side effects, which should be explained by a medical professional. A doctor can decide which medications are best suited for a patient based on the individual case of glaucoma, medical history, and current medication regimen.

Treatments vary depending on the type of glaucoma. The most common include:

Open-angle glaucoma treatment normally begins with medications, usually eye drops or, rarely, pills that either help eye fluid drain more effectively or cause the eye to produce less fluid. Several forms of laser surgery can also help fluid drain from the eye. Conventional filtration surgeries such as the glaucoma drainage implant are sometimes used to create a new opening for fluid drainage.

Acute angle-closure glaucoma (a medical emergency) is treated with medications and/or laser procedures.

Chronic angle-closure glaucoma is treated with a laser procedure, often in an office or clinic under local anesthesia, and with medications.

Normal-tension glaucoma is currently treated in the same ways as open-angle glaucoma. When this form of the disease is better understood, treatment strategies may be modified.

Congenital glaucoma is usually treated with medications and one of two forms of eye surgery.

Juvenile glaucoma is treated using medications, laser surgery and conventional filtration surgery.

Secondary glaucoma can be open-angle or angle-closure, and acute or chronic. Treatment depends on these factors and whether the underlying condition causing increased eye pressure needs to be addressed.

New research is focused on lowering pressure inside the eye, and finding medications to protect and preserve the optic nerve from the damage that causes vision loss. Scientists are also investigating the role of genetics in glaucoma, and over the last few years their understanding of this factor has progressed. Researchers have discovered genes associated with congenital glaucoma, juvenile glaucoma, normal-tension glaucoma, adult-onset open-angle glaucoma, pigmentary glaucoma and other conditions related to secondary glaucoma.

Individuals at high risk for glaucoma should have a dilated-pupil eye examination at least every two years. Eye doctors use several tests to detect glaucoma:

Tonometry measures the pressure inside the eye. Examples of tonometers include:

• The air-puff (noncontact) tonometer, which emits a puff of air. Eye pressure is measured by the eye's resistance to the air.
• The applanation tonometer, which touches the eye's surface after the eye has been numbed and measures the amount of pressure necessary to flatten the cornea. This is the most sensitive tonometer, but a clear, regularly-shaped cornea is needed for it to function properly.
• The electronic indentation method, which measures pressure by directly contacting anesthetized eyes with a digital pen-like instrument.

In pupil dilation, special drops temporarily enlarge the pupil so the doctor can better view the inside of the eye. Various instruments allow the doctor to determine the thickness of the cornea, to view the front and/or the interior of the eye, and to monitor optic nerve changes over time.

Visual field testing measures the entire area seen by the forward-looking eye to document straight-ahead (central) and/or side (peripheral) vision.

A visual acuity test uses an eye chart to measure sight at various distances.

Thanks for your question. This is a difficult question to answer without knowing more of your history, examining your eyes, and getting a sense of the pace of your glaucoma progression. While it is true that surgery often lowers the pressure more than drops, your doctor is correct in that surgery has inherent risks. Eye drops (and laser) are generally used as first-line therapies because they are safe and effective, and many patients do not see a progression of their glaucoma with just using medications. Of course, there are side effects of the eye drops as well, but you will not know if you will experience them until you give it them a try. It seems reasonable (based on the limited knowledge of your situation) to try eye drops (or laser) first. If they do not work, you will not have lost much (if any) ground and can then proceed with surgery. Please follow up with your eye doctor to determine the next steps and to further discuss your concerns.

Thank you for your question. Unfortunately it is difficult for me to advise you about the necessity of surgery without reviewing your ophthalmic history and performing an examination. I can give you some advice about what questions or options to consider prior to having surgery. Are there other eye drops that you can take without intolerable side effects and that lower your eye pressure further? Are you a candidate for glaucoma laser treatment (laser trabeculoplasty)? Have you had worsening of visual field or optic nerve structure over time at your current eye pressure? Unfortunately, it is a known side effect of glaucoma surgery that vision can sometimes decrease, often due to cataract or lens changes, but this is usually reversible. Lastly, you could consider seeking a second ophthalmologist’s opinion, perhaps from a glaucoma specialist.

Thanks for your question. I’d like to reassure you that the redness in your eyes does not mean that you are approaching blindness. Your doctors may be correct that the redness is due to the glaucoma eye drops. You could try to switch over to preservative-free formulations that may be less irritating. Another intervention that might help is the use of preservative-free artificial tears during the day and an ointment at nighttime. You mentioned that your doctors think it is due to a change of the glaucoma eye drops, so it would be helpful for you to know which medication changed. If you know which eye drop is causing the problem you could either switch formulations (such as a preservative-free formulation) or try a different glaucoma eye drops. Please discuss these options with your eye doctor. Good luck!