Glaucoma is an eye disease, or as most doctors say, a group of diseases that slowly and gradually damage the optic nerve. Being the number one cause of permanent blindness in the world, glaucoma usually has no symptoms and can only be detected through regular eye check-ups. Glaucoma is genetically inheritable and is linked with the buildup of intraocular pressure inside the eye.
Types of Glaucoma
With many different types of glaucoma, scientists have classified them into two main categories. Open angle glaucoma lasts longer while closed angle glaucoma occurs both suddenly and over a long period of time.
Open angle glaucoma is the most commonly found glaucoma, accounting for over 90 percent of cases in the US. Its intensity increases with age because the drainage nerves may gradually clog over time. Although the eye may appear normal, the fluid in the eye, called aqueous humor, does not flow through properly causing excessive pressure.
Closed angle glaucoma may be uncommon in the US, but a high number of people in Asia suffer from it. Being both acute and chronic, closed angle glaucoma can cause a sudden upsurge of pressure inside the eye. The narrow angle between the iris and the cornea may result in poor drainage.
Glaucoma Risk Factors
Also known as the sneak thief of light, glaucoma can destroy sight without any prior symptoms. Certain factors increase the risk of falling prey to glaucoma, including:
- Age over 40
- Having a family history of glaucoma
- Afro-American descent
- Loss of vision
- Using certain steroids
- Having a history of increased intraocular pressure
Glaucoma usually doesn’t have any symptoms. Vision loss only starts occurring in the later stages of the disease. A person with fluctuating levels of the pressure may experience blurry vision and see halos around light. But that is very rare. Patients suffering from acute glaucoma often experience severe eye pain, blurred vision, headaches and nausea accompanied by vomiting. People with acute glaucoma often appear to be red and their pupil enlarges, becoming non-reactive to light.
Tests and Eye Examinations to Diagnose Glaucoma
Glaucoma can be detected by an eye care professional through one or more of the following painless tests:
- Tonometry: This test measures the level of pressure in the eye by determining the firmness of its surface.
- Pachymetry: In this test, the pachymeter tip is contacted lightly with the surface of the eye to measure the thickness of the cornea. This is only done after the eye has been numbed with anesthetic drops.
- Gonioscopy: after numbing the eye, doctors place a contact lens with mirrors inside. The mirrors allow the doctor to view the interior of the numb eye from different angles. With this test, doctors can effectively determine the drainage angle and any other anomaly in the angle area.
- Ophthalmoscopy: The doctor uses a handheld device to look through the pupil to examine the optic disc located at the back of the eye.
- Optic nerve tomography: This creates a 3-D figure of the optic disc to assess the nerve fibers and the optic disc damage.