Glaucoma

Glaucoma is the leading cause of irreversible blindness worldwide. It is a progressive disease of the optic nerve that typically affects the peripheral vision first. Because early in the disease there are no symptoms, glaucoma is often referred to as "the silent thief of sight." In the majority of patients with glaucoma, the pressure inside the eye is elevated. Medical, surgical and laser treatments are available to lower intraocular pressure and reduce the risk of optic nerve damage. With early detection and treatment, vision loss and blindness from glaucoma can typically be prevented.

An annual glaucoma follow-up includes:

1. A complete dilated eye examination
2. Intra-ocular pressure measurement
3. Optic nerve evaluation
4. Visual field evaluations

What are the risk factors for Glaucoma?

Elevated intraocular pressure, advancing age, African ancestry, family history, history of ocular injury, and chronic use of corticosteroid medicines are the major risk factors. Many patients with glaucoma, however, have none of these risk factors.

What are the different types of Glaucoma?

There are several different types of glaucoma, all of which have progressive optic nerve injury and visual field loss in common. Except for Normal Tension Glaucoma, all are associated with elevated intraocular pressure.

 

Types of Glaucoma

Angle Closure Glaucoma

Closure of the drainage angle results in an increase in pressure in the eye. This can occur suddenly in acute angle closure or gradually in chronic angle closure glaucoma.  Symptoms include severe eye pain, blurred vision, haloes around lights, nausea and vomiting. Treatment is needed immediately to minimize optic nerve damage. Angle closure glaucoma is usually treated with laser or microsurgery. Patients that are farsighted, especially those with cataracts or Asian ancestry are at risk for this type of glaucoma. Patients with narrow angles of the eye may need preventative laser treatment to avoid angle closure glaucoma.

Exfoliative Glaucoma

This common type of secondary glaucoma is due to clogging of the drainage channels by an abnormal white substance that is deposited throughout the eye. Elevated intraocular pressure is treated with medication, laser or surgery.

Glaucoma Suspect

This diagnosis refers to patients believed to be at high risk for developing glaucoma or in whom glaucoma is suspected but cannot be confirmed. A person may be considered a glaucoma suspect on the basis of high intraocular pressure, a suspicious appearance of the optic nerve or visual field, or the presence of risk factors.

Normal Tension Glaucoma

In this type of glaucoma, characteristic optic nerve damage and visual field loss occur at pressures within the normal range. Studies have confirmed that lowering pressures further with medications, laser or filtering surgery results in a lower risk of disease progression.

Open Angle Glaucoma

Open angle glaucoma is the most common type of chronic glaucoma in which the intraocular pressure is high but the drainage angle is open and normal in appearance. Elevated pressure in the eye damages the optic nerve and results in permanent vision loss. OAG can be treated with eye medications, laser surgery and filtering incisional surgery.

Pigmentary Glaucoma

This type of glaucoma is a form of secondary glaucoma that occurs when pigment granules from the iris (the colored part of the eye) are rubbed off and clog the drainage channels in the eye, causing the pressure to rise. Medication, laser or surgery may be used for treatment.

Secondary Glaucoma

Secondary glaucoma occurs as a result of an eye injury, inflammation, tumor, cataracts, diabetes or vascular disease. Sometimes, medications such as steroids can cause secondary glaucoma. Treatment is directed toward both the underlying problem as well as lowering pressure with standard glaucoma therapies.

Click here to visit the American Academy of Ophthalmology's Eye Smart website to learn more about glaucoma.