What Is Glaucoma?

  • By Germaine Shock
  • 12 Jan, 2017

January… the start of a new (hopefully better) year, the peak of winter, and the season of self-improvement. But January isn’t only the month of resolutions and snow days. Did you know January is also glaucoma awareness month? In case you didn't, we’re here to help spread said awareness and hopefully add taking better care of your vision to your list of New Year to-do's. So let’s jump right in.

What Is Glaucoma?

Most of you have probably at least heard of glaucoma, but what exactly is it? Glaucoma is actually the term for a group of diseases that cause damage to the optic nerve resulting in vision loss and/or blindness. Still lost? To better understand how this happens, let’s go over some of the eye’s anatomy.

At the very back of each eye you have something called an optic nerve. The optic nerve is made up of a group of multiple nerve fibers that connect the brain to the eye and transmit signals from your retina (light sensitive tissue that lines the inside of the eye) that are then translated into the images we see. 
diagram of the anatomy of an eye

The insides of your eyes also contain two gel-like fluids that help maintain the eye’s shape. These are called the aqueous and vitreous humor.The aqueous humor is produced behind the iris  (the colored part of your eye) and fills the space between the iris and the innermost layer of the  cornea  as well as the area between the iris and the lens (transparent flexible tissue that helps focus light and images). In addition to helping the eye maintain its shape, the aqueous humor also provides nutrients to the parts of the eye that lack their own blood supply.

What Does This Have To Do With Glaucoma?

You can think of the eye as being similar to a balloon in that you don’t want there to be too much pressure inside, but you don’t want there to be not enough pressure either. So with a constant supply of fluid being created, how is this balance maintained?

The eye regulates its internal pressure by utilizing a drainage system. Excess fluid exits the eye by flowing through spongy tissue between the iris and cornea called the  trabecular meshwor k and into a drainage canal. Any disturbance in this balance of production and drainage will cause a buildup of excess fluid and in turn an increased intraocular eye pressure (IOP). 

Over time, the constant increase of pressure on the optic nerve will eventually cause damage to individual optic nerve fibers, leading to vision loss. This process of pressure build up and optic nerve damage is called glaucoma.

illustration of a normal eye versus an eye with glaucoma

Different Kinds Of Glaucoma

As mentioned earlier, glaucoma is a group of diseases - meaning there are several different types.

´╗┐Primary Open Angle Glaucoma

Primary Open Angle Glaucoma (POAG) is the most commonly seen type of glaucoma. Remember the anatomy lesson we just had? This is the process that POAG follows. The internal ocular pressure increases gradually due to a blockage in the eye’s drainage canals leading to damage of the optic nerve. With this type of glaucoma vision loss is slow and often displays no other symptoms. There is also a strong link in genetic predisposition associated with POAG.

Angle Closure Glaucoma

Angle Closure Glaucoma is a much less common form caused by a narrowing or completely closed entrance to the drainage canal. Think of this like the door to the hallway being closed vs. there being boxes blocking part of the hallway (angle closure vs. open angle glaucoma). When this is the case, eye pressure can rise very quickly. This dramatic increase will cause sudden eye pain, nausea, headaches, blurred vision, and requires immediate medical treatment.

Normal Tension Glaucoma 

Having what would typically be considered a ‘normal’ IOP doesn’t mean you are out of the woods for glaucoma. Also referred to as low-pressure glaucoma, normal tension glaucoma occurs when the nerve is damaged even though the internal pressure is not excessively high. Because of this, the eye pressure needs to be kept at an even lower level to prevent further progression. While the cause for this type of glaucoma is still not completely understood, it is believed to be due in part to either an unusually fragile optic nerve or reduced blood flow to the nerve.

Other Types Of Glaucoma

There are also a handful of other types of glaucoma including secondary, congenital, pigmentary, and neovascular. For more information check out this page from the Glaucoma Research Foundation .
photo of an optometrist performing a slit-lamp biomicroscope exam on a patient

Risk Factors

Glaucoma can affect anyone at any age. However, there are certain factors that can put you at more of a risk for developing this sight stealing disease. It is important to stay on top of your annual eye health exams since glaucoma is one of the many eye complications that can present no symptoms until vision is lost. If you have any of the risk factors listed below, be sure to talk with your Optometrist about glaucoma specific testing.

  • Over the age of 40
  • Family history of glaucoma
  • African American, Hispanic, or Asian heritage
  • Systemic conditions such as high blood pressure or diabetes
  • Thin corneas
  • High glasses prescription
  • Recent or previous eye injury
  • Consistently elevated IOP measurements
Stay tuned for our next post which will cover symptoms to look out for as well as treatment information.

Wanna see us for your eyecare needs? Click here to read about what to expect from your eye exam.


By Germaine Shock 06 Dec, 2017

Do your friends often comment on your ‘unique’ choices when it comes to matching colors and patterns? Being fashionably challenged might not be entirely your fault (or it could be). You might be having an extra difficult time due to color blindness.

Color blindness is actually somewhat of a misuse of the word as those affected by the condition can actually still see color - just with a more limited palette. Color vision deficiency is actually the more accurate term. However, there is a rare form of color vision deficiency known as achromatopsia where you are in fact completely devoid of color in your world- but we’ll get to that one a little later. For now, let’s start with the basics.

By Germaine Shock 01 Aug, 2017
By now most all of you have likely seen or are at least familiar with a solar eclipse. Without getting into too much of the scientific details, a solar eclipse happens when the moon moves between the sun and earth during its orbit causing a partial or complete blockage of our view of the sun. Although a solar eclipse only lasts for a few minutes, its thrilling impact will stay with you for much longer.
By Germaine Shock 20 Jul, 2017
School's out for summer! With a little extra free time and flexibility in your schedule, now is the perfect time to  bring your kiddos in for their eye health exams. Most parents will logically assume that since their child hasn’t had any complaints, they must not be having any problems - or that their child is simply too young to need an eye exam. Think again! 
By Germaine Shock 06 Jul, 2017
Sometimes when it comes to kiddos, you’ll find yourself navigating through some gray areas. For example, determining how much screen time is too much - or how old they should be to watch that scary movie. These definitive numbers are so hard to pinpoint simply because no two children are the same. They all mature at different rates, and we as parents have to adjust accordingly. Fortunately, here are a few tips to help in one of those gray areas -  figuring out if your child is ready for contact lenses.
By Germaine Shock 23 Jun, 2017
We have all made a questionable decision or two at least once in our lives. However, when it comes to your eyes and vision, this is one area where it is always better to be safe than sorry. Here are a few of the most common mistakes made by contact lens wearers and a safer alternative to keep those peepers healthy.
By Germaine Shock 14 Jun, 2017

More than likely if you are reading this, you’ve experienced the strange sensation of an eyelid twitch. It can happen anywhere, at any time, and almost always stops the moment you try to point it out to someone else (and of course resumes the second they turn away just to make you look extra crazy). Well you aren’t crazy - at least in this case - eyelid twitches are a real thing!


Better known in professional lingo as “myokymia”, this twitching sensation is the result of involuntary, spontaneous, rippling muscle contractions. These spasms can actually occur in almost any of the muscles in your body. When relating to the eyelids, myokymia is most common in your lower lids but can happen in your top lids as well.

Eyelid myokymia is typically very temporary. The twitching will usually only last for a few minutes, but in some rare cases can last for a few days or even weeks.

Your doctor will likely advise you that there is no cause for concern as common Myokymia resolves on its own without the need for treatment. Other than causing mild annoyance, the eyelid twitching shouldn’t cause any long term complications or interference with your vision.
By Germaine Shock 01 Jun, 2017

Do your eyes ever feel dry and itchy? Do you ever experience eye fatigue, redness, blurred vision, or excessive watering? You could be suffering from dry eyes - especially if you live in Oklahoma City which ranks as the 17th driest city in the U.S. And despite the name, dry eye isn’t just an annoying feeling - it’s a legitimate chronic eye disease that affects an estimated 4.88 million Americans over the age of 50 alone. And since another estimated 89% of the population have never even heard of Dry Eye Syndrome, it’s easy to see why some would just write off those annoying symptoms as a normal part of their lives.

By Germaine Shock 16 May, 2017

In honor of Mother’s Day kicking off Women’s Week, the Eye- Q blog has decided to dedicate a post solely to women’s eye health related issues. So what makes women’s eye health so special? Women are actually more commonly affected than men by a number of ocular health issues including dryness, cataracts, age related macular degeneration, and complications from autoimmune disorders such as Sjogren's or lupus. Furthermore, according to Prevent Blindness America, 66% of people who are blind or visually impaired are women.

Let’s start with that statistic - why are women more at risk for eye complications than men?
By Germaine Shock 05 May, 2017
May is healthy vision month - and as we draw nearer to the official first day of Summer, what better time to discuss one of the most commonly overlooked parts of eye health - UV protection. Most of you are probably fully aware of the negative effects UV rays can have on your skin, but did you know the sun can be just as damaging to your eyes?
By Germaine Shock 25 Apr, 2017

No, it’s not a typo. Sjogren’s - pronounced show-grins - is a type of autoimmune disorder that causes inflammation and damage to various parts of the body; most commonly the tear and saliva glands. This damage results in symptoms ranging from dryness and discomfort to difficulty swallowing and can even affect the lungs and kidneys.

So why exactly does this happen? Let’s start with a quick health lesson. The immune system is responsible for fighting disease and killing harmful viruses and bacteria. However, with autoimmune diseases, your immune system has a hard time knowing when to stop fighting and mistakenly attacks your own body. With Sjogren’s, your exocrine glands - the glands that secrete moisture such as saliva, sweat, tears, breast-milk, gastric mucous, etc - become the main targets.
More Posts
Share by: