This post lists some of the tests you might have during a glaucoma physical examination. These include the visual field test, the corneal thickness and angle tests, the imaging of the optic nerve, and the check of your eye pressure.

Glaucoma is an umbrella term for a group of diseases that all damage the optic nerve in the same way. The group of nerve fibers at the back of the eye is called the optic nerve. It sends messages from the retina to the brain about what the eye sees. Clinical tests can tell the difference between the different types of glaucoma. The one that happens most often is primary open-angle glaucoma (POAG). Individuals who have POAG usually don’t have any signs at all until the disease gets very bad. Most people with severe disease lose their ability to see on the sides and have poorer vision overall, which can make everyday tasks like driving very difficult. The treatments that are currently available have been shown to slow down the disease but not heal damaged visual nerves.

Types of  Glaucoma

Open-angle glaucoma is the most common type, making up almost 90% of all cases.

The front part of a healthy eye makes intraocular fluid. It moves through the pupil to the back of the eye and into the bloodstream through the eye’s drainage system, which is made up of a web of drainage tubes around the iris’s edge.

The gap between the lens and the cornea is wide in people with open-angle glaucoma. This lets fluid flow through the eye. However, the drainage tubes get clogged up, which raises the pressure in the eyes and causes the optic nerve to atrophy, leading to vision loss.

We don’t see many people with narrow-angle glaucoma. This condition makes the gap between the iris and cornea narrow.  When the pupil gets bigger, the intraocular fluid can get stuck, which causes the outer part of the iris to bunch up and fill the drainage canals. This raises the pressure in the eye, which damages the optic nerve.

Secondary glaucoma is any type of glaucoma where the high eye pressure can be linked to a known cause. It could be due to damage to the eye, inflammation, some prescription drugs or medicines (like steroids), or severe cataracts or diabetes.

People are identified with congenital glaucoma, which is also called juvenile or infantile glaucoma, in their first few years of life. It doesn’t happen very often and is usually caused by the eye’s drainage system not developing properly before birth. Children with glaucoma often have eyes that are too big, the lens is cloudy, and they are sensitive to light.

How is glaucoma diagnosed?

You will be checked for signs of glaucoma when you go to the eye doctor for a full glaucoma examination.  An ophthalmologist or optometrist will check the pressure inside your eye, the shape, and color of your optic nerve, your visual field, the angle where your iris meets your cornea, and  (pachymetry) thickness of your cornea at this visit.

Scientists don’t know for sure what causes the most common types of this disease. But if you have high fluid pressure in one or both eyes, you are more likely to get the disease. The cells inside your eyes are always making fluid, which keeps them healthy. Your iris (the colored part of your eye) and cornea (the clear front layer of your eye) meet in a drainage system with holes in them. This is how the fluid leaves your eyes.

As long as the amount of fluid that comes in and goes out of your eye is equal, the pressure inside your eyes stays in a healthy range. When the draining system gets clogged, water can’t drain as quickly as it should. Fluid builds up in your eye if it makes more than it can drain. This makes the pressure in your eye rise. The high pressure could hurt the optic nerve, which would make it very hard to see.

To keep your eyes from losing their ability to see permanently, you should see an eye doctor regularly to check for glaucoma. This is especially important if you have known risk factors for the disease, like a family history of it. It is important to know the basics of the tests for glaucoma so that you can work with your doctor to make an informed choice about your treatment options. The following lists some of the tests.

Glaucoma tests look at many parts of your eyes and vision, such as:

To measure eye pressure with tonometry tests, you can do a few different things:

• Do the air-puff test. Your eye doctor will prop your chin up on a machine and blow a puff of air into your eye. Every so often, this easy, quick test is used to check for glaucoma. Your doctor will do more eye tests to get a more exact reading if the first ones show that your eye pressure is high.
• Use of applanation tonometry. Before testing your eye pressure in one of these ways, your doctor will put drops in your eyes to numb them.
• You will put your chin on a slit lamp, which is a special kind of microscope. Your eye doctor will look at your eye through the slit lamp and test the pressure in your eye by gently putting a special probe on it.

The tool checks the pressure in your eyes.

Pachymetry measures how thick your corneas are. The clear layer on the front of your eye is called the cornea. The thickness of it can change the results of your eye pressure tests. A pachymetry test tells your eye doctor more about how high your eye pressure might be if the corneas are abnormally thin or thick. Your eye doctor will put drops in your eye to numb it, then they will put a small device on your cornea to measure how thick it is.

Optic Nerve Examination

A test with enlarged pupils will be done by your eye doctor to check for damage to your optic nerve. This test is part of a regular check-up for glaucoma. You can also call it ophthalmoscopy. You will be given eye drops that make your pupils bigger. Pupils are the holes in your eyes that let light in. Your eye doctor will use a device with a light and an enlarged lens to look into your eye while you look straight ahead.

Visual Field Exam

Your side vision or peripheral vision. A visual field test, which is also known as perimetry, checks how well you can see from the side. You can take the test in a number of different ways. You’ll look straight ahead most of the time. Things will be shown off to the sides of your field of view. You’ll say when you can see lights without moving your eyes.

Trabecular meshwork and the angle exam

The area that drains fluid from the inside of your eyes. If your eye doctor thinks you might have glaucoma, they may do a gonioscopy to check whether the drainage system in your eye is open (open-angle glaucoma) or closed (closed-angle glaucoma). Drops will numb your eyes. After that, your doctor or nurse will put a special kind of contact lens in your eye. There is a mirror on the lens that shows you where the eye fluid flows.

When should you get a glaucoma eye examination (screening exam)?

Glaucoma exams may be part of an eye check you need if you’re having problems with your vision like:

• There are blind spots.
• Seeing blurry.
• Pressure or painful eyes.
• Headaches
• Lights make rainbow shapes when you look at them.
• Red eyes.

People who are at risk for glaucoma should also get full eye checks on the following plan, according to the American Academy of Ophthalmology (AAO):

• Every one to three years for people 40 to 54 years old.
• Every one to two years for people 55 to 64 years old.
• Every six to twelve months for people 65 and up.

What should I do if I have glaucoma?

Your doctor will tell you what to do next. They might suggest that you make regular follow-up meetings to check your eyesight. To treat myopia, they may suggest medications such as:

• Eye drops or pills that lower the pressure in your eyes.
• Surgery to make a hole in your iris so that extra fluid can drain easier and lower the pressure in your eyes.
• Surgery to put in tubes that drain extra fluid.
• A laser treatment can help get rid of fluid.

When to start Treatment for Glaucoma

Doctors will tell you how to treat your open-angle glaucoma based on your specific case. Your doctor looks at a number of things before making a treatment plan. These include the chance that the disease will get worse and that you will lose your sight. These risks depend on your age, race, family history, other medical conditions you may have, and the state of your optic nerve.

If you are a glaucoma suspect, which means that your optic nerve looks a little off but still works, or your pressures are high, your doctor may want to keep an eye on you until the condition changes or gets worse, and only then will they start treatment. “Glaucoma suspect” is what doctors call someone whose tests aren’t quite clear.

Your doctor may also think about treating you if someone in your family has a form of the disease that gets worse over time. Glaucoma usually gets worse slowly over time, so your doctor may want to make sure you are a good choice for treatment before giving you medicine. 

Your doctor may want to start treatment right away if your glaucoma is mild to serious so that you don’t lose your sight.

FAQ’s

What is a physical exam for glaucoma?

For signs of damage that could be caused by glaucoma, the doctor will look at the optic nerve in the back of the eye. Also, the drainage angle will be checked.  They use pictures of the optic nerve or imaging tests like optic coherence tomography to find out more about it.

What is the most obvious sign of glaucoma?

Open-angle glaucoma doesn’t show any signs in most people. Most of the time, signs don’t show up until late in the disease. Most of the time, losing side vision is the main sign.

Can glaucoma be found during a normal eye exam?

A test with enlarged pupils will be done by your eye doctor to check for damage to your optic nerve. This test is part of a regular check-up for glaucoma. You can also call it ophthalmoscopy. You will be given eye drops that make your pupils bigger. Pupils are the holes in your eyes that let light in.

Which test is most likely to find glaucoma?

An optical coherence tomography (OCT) scan is the first test that can be used to diagnose glaucoma. It may be the most exact test in the world for helping doctors figure out if someone has glaucoma.

Is a glaucoma examination painful?

The tests for glaucoma are quick and don’t hurt. As part of the test, the main optic nerve in the eye is looked at.

What is the rate of progression of glaucoma?

Glaucoma is a problem that gets worse over time. Glaucoma usually takes between 10 and 15 years to go from causing early damage to total blindness if it is not treated. If your IOP is between 21 and 25 mmHg, it takes 15 years to progress. If it’s between 25 and 30 mmHg, it takes seven years, and if it’s more than 30 mmHg, it takes three years.