What is Glaucoma?

A healthy optic nerve is essential for good vision. But, for those who suffer from glaucoma, this nerve is usually damaged beyond repair.

Glaucoma is a caused by a group of diseases that damage the optic nerve (a bundle of nerve fibers that are responsible for carrying information from the eye to the brain), resulting in vision loss and blindness.

It is the second-leading cause of blindness in both this country and the world, coming in behind macular degeneration and cataracts respectively.

Typically, glaucoma is associated with a condition named ocular hypertension i.e. higher-than-normal- pressure in the eye. But, it is also possible for patients to be stricken with this ailment even when IOP, intraocular pressure, is normal.

Types of Glaucoma

There are several types of glaucoma, tut they can be broken down into two major categories:Narrow angle glaucoma: In this instance, the drainage angle is blocked, making it impossible for the watery fluid to reach it.

There are several types of narrow angle glaucoma and they include vascular glaucoma, chronic angle closure glaucoma, and acute angle closure glaucoma.Open-angle glaucoma: In this instance,the watery fluid is able to easily access the drainage angle.

There are various forms of open-angle glaucoma and they are primary open angle glaucoma, congenital glaucoma, secondary glaucoma, pseudo exfoliation glaucoma, pigmentation glaucoma, and normal-tension glaucoma.

In both cases, the angle refers to the drainage angle that controls the flow of the aqueous (watery) fluid that is continuously being produced in the eye.


Glaucoma Symptoms

Typically, this disease has few or no initial symptoms, this is why it considered to be the ‘silent thief of sight.’ In fact, most patients don’t experience pain or have any inkling that their optic nerve has been damaged until their vision loss has become noticeable.

Because of this lack of symptoms, glaucoma is usually undetected until after the optic nerve has been irreversibly damaged, resulting in varying degrees of permanent vision loss.
But, in the case of acute angle-closure glaucoma, things don’t go along like business as usual.

In fact,symptoms may appear suddenly and include:

  • Vomiting
  • Nausea
  • Sharp eye pain
  • Halos around the eyes
  • Blurry vision

Although the consequences of untreated glaucoma can be debilitating, with early detection and treatment, it is possible to protect your eyes and prevent serious vision loss.

Screenings, Tests, and the Diagnosis of Glaucoma

Eye doctors check for glaucoma during routine eye exams. To check for this ailment, the doctor will first numb your eyes with special eye drops and a tonometer is used to measure intraocular pressure.

The normal IOP reading is below 21mmHg (millimeters of mercury), a unit of measurement that is determined by how much force in exerted in a given area. A high IOP reading means that there is a problem with the amount of watery fluid in the eyes i.e. either the eye isn’t draining properly or is making too much fluid.

For instance, if your IOP is higher than 30mmHg, the risk of vision loss from glaucoma is 40 times more than someone with an IOP of 15 mmHg or lower.

Other techniques of monitoring this eye diseaseinvolve the use of innovative imaging technology to create measurements as well as baseline images of the optic nerve and internal structures in the eye.

They include:

  • Con-focal scanning laser ophthalmology
  • Optical Coherence Tomography
  • Scanning laser polarimetry

In addition, these methods take addition measurements and images at specified times to make sure that there haven’t been any changes that may indicate signs of progressive glaucoma damage.

Doctors also use visual field testing to determine if vision loss is indeed being caused by glaucoma. During this testing, patients stare straight ahead into a special machine and must hit a button when a blinking light is seen in their peripheral version.

This test can be repeated regularly to ensure that patients don’t have blind spots in their vision caused by damage to the optic nerve. They are also used to determine the progression or extent of vision loss from glaucoma.

Finally, doctors may also performer a gonioscopy to make sure that the watery fluid is able to drain freely from the eye. During this procedure, a bio microscope is used with special lenses to give your eye doctor the ability to see the drainage angle inside of your eyes.

Ultrasound bio microscopy in another technique used by doctors to inspect the drainage angle.

Glaucoma Treatments

There are several treatments that can be used to slow down or stop the progression of glaucoma and they include surgery, medication, and lasers. The specific solution that will be implemented is based on the severity of the patient’s glaucoma.

Usually medicated eye drops are the first line of defense in the fight to control glaucoma because they help get eye pressure under control and prevent permanent eye damage.

Unfortunately, because glaucoma is painless, there is a tendency for patients to become careless about the use of the eye drops, making them not as effective as they could be. In fact, one of the major reason for blindness caused by glaucoma is noncompliance with the prescribed glaucoma medication program.

Preventing Glaucoma

There is a recent European study that shows that exercise may help some people reduce their risk of glaucoma i.e. long term benefit of physical exercise include a reduction in low ocular perfusion pressure, a important risk factor glaucoma.

For instance, the results of the study showed that participants who engaged in moderate physical exercise for about 15 years before the study reduced their low ocular perfusion pressure by as much as 25 percent.

In addition to exercising on a regular basis and living an active lifestyle, it is possible to reduce the risk of glaucoma by eating a healthy and varied diet, stopping smoking, and maintaining a healthy weight.