What is Glaucoma?

Glaucoma is an eye disease in which the pressure inside the eye is high enough to damage the optic nerve. The optic nerve is the “cable” which connects your eyeball to your brain, allowing you to see. All eyes have aqueous fluid inside of them. This fluid is needed to maintain a healthy pressure inside of the eye. When the amount of fluid inside of the eye increases, the pressure inside the eye increases.  Although it typically occurs in patients in their 70’s and 80’s, it is not uncommon to find younger people with early signs of glaucoma. Early detection and treatment are essential in preventing vision loss. Untreated glaucoma leads to permanent loss and even blindness in some cases.


Glaucoma has no symptoms. It is not painful. The vision loss is slow and at the edges, or periphery, of vision. It is impossible to detect without an eye exam.

3 Types of Glaucoma: Open-Angle, Narrow Angle, & Normal Tension

The three most common types of glaucoma include primary Open-Angle, Low or Normal Tension, and Narrow Angle. Let’s review each of them below.

Primary Open Angle

Primary open angle glaucoma is the most common type of glaucoma. There is still some disagreement on what actually causes POAG, if it is an issue with the eye making too much aqueous fluid, or the fluid not being able to drain out. Most likely it is a combination of both.

Narrow Angle

The “angle” in the eye refers to the structure between the iris and the cornea, where a good portion of the eye’s aqueous fluid leaves the eye. If there is a problem with this structure, it can prevent the fluid properly draining, causing increased eye pressure.


Normal or Low Tension Glaucoma occurs in the presence of normal or low eye pressure. Again, the exact cause is still up for debate, but diabetes, low blood pressure and sleep apnea are all risk factors. It’s believed that the optic nerve itself is weak, and cannot withstand even a normal or low amount of eye pressure.


Glaucoma is a treatable disease. Treatment always involves obtaining a lower or healthy eye pressure. This healthy pressure is different for everyone, and will be determined by the eye doctor. Initial treatment usually involves the use of a single eye drop once a day. Additional drops may be added as needed. If drops alone are not sufficient to control the disease, laser treatment or surgery may be recommended. We often initiate treatment to prevent it in patients who are at unusually high risk of getting the disease down the road.

Glaucoma FAQ’s

How high does my eye pressure have to be to damage my optic nerve?

Everybody is different! Eye pressure alone does not determine whether or not you have glaucoma; other factors must be taken into account. Thorough examination and various tests are used to detect glaucoma early and to follow its course during treatment.

How could I have glaucoma? I see perfectly!

Early vision loss from glaucoma is subtle and impossible to notice, even by those who are very visually attentive! If a person waits until they notice vision loss from glaucoma, the disease is advanced and difficult to treat. These people are at great risk of going blind. It is important for those at risk for glaucoma to be examined on a regular basis.

How do I know if I am at risk of getting glaucoma?

Following your comprehensive eye examination, your doctor will inform you of any risk factors predisposing to glaucoma and recommend follow up accordingly.

What are the risk factors for glaucoma?

There are many. Some of the more common risk factors include family history, fragile optic nerves, pseudoexfoliation (white material found inside the eye, common among those of northern European heritage), and high pressure inside the eye.

What is vision loss due to glaucoma like?

In the early stages of the disease, vision loss is typically in the peripheral visual field where it cannot be picked up without specialized testing. Vision loss then gradually progresses into the middle part of your vision, where it eventually interferes with activities such as driving and reading. Vision loss from glaucoma is permanent. Untreated, and sometimes in spite of treatment, glaucoma can lead to total blindness.

Are there different kinds of glaucoma?

There are many different kinds. The comments above are most pertinent to those who have “open angle” glaucoma; this is by far the most common kind of glaucoma that we see in our patients. If you are at risk of a less common type of glaucoma, your doctor will certainly inform you and provide treatment as appropriate.

Where can I get more information about glaucoma?

Follow this link to the American Academy of Ophthalmology information on glaucoma.

What if I have glaucoma and cataracts?

Patients who have glaucoma and cataracts might benefit from a new medical device which can lower intraocular pressure. This device, the iStent, is implanted during cataract surgery. It may reduce the need for glaucoma eye drops.

Click here to learn more about iStent.

Want to learn more about iStent? Check out the links below:

Are there glaucoma laser treatments available at Relf?

Yes. Selective Laser Trabeculoplasty (SLT) is a procedure our doctors perform. SLT targets only specific pigmented cells to increase fluid drainage from the eye. SLT may reduce the need for lifelong use of eye drops. Your Relf Eyecare doctor will let you know if this is a good option for you.

Contact Us

We're not around right now. But you can send us an email and we'll get back to you, asap.

Start typing and press Enter to search