Glaucoma

Glaucoma
Acute angle closure glaucoma of a person's right eye (shown at left). Note the mid-sized pupil, which is non-reactive to light, and redness of the white part of the eye.
Specialty	Ophthalmology, optometry
Symptoms	Vision loss eye pain mid-dilated pupil redness of the eye nausea [1][2]
Usual onset	Gradual, or sudden[2]
Risk factors	Increased pressure in the eye, family history, high blood pressure[1]
Diagnostic method	Dilated eye examination[1]
Differential diagnosis	Uveitis, trauma, keratitis, conjunctivitis[3]
Treatment	Medication, laser, surgery[1]
Frequency	6–67 million[2][4]

Glaucoma is a group of eye diseases that lead to damage of the optic nerve, which transmits visual information from the eye to the brain. Glaucoma may cause vision loss if left untreated. It has been called the "silent thief of sight" because the loss of vision usually occurs slowly over a long period of time.^[5] A major risk factor for glaucoma is increased pressure within the eye, known as intraocular pressure (IOP).^[1] It is associated with old age, a family history of glaucoma, and certain medical conditions or medications.^[6] The word glaucoma comes from the Ancient Greek word γλαυκός (glaukós), meaning 'gleaming, blue-green, gray'.

There are different types of glaucoma, but the most common are called open-angle glaucoma and closed-angle glaucoma.^[7] Inside the eye, a liquid called aqueous humor helps to maintain shape and provides nutrients. The aqueous humor normally drains through the trabecular meshwork. In open-angle glaucoma, the draining is impeded, causing the liquid to accumulate and pressure inside the eye to increase. This elevated pressure can damage the optic nerve. In closed-angle glaucoma, the drainage of the eye becomes suddenly blocked, leading to a rapid increase in intraocular pressure. This may lead to intense eye pain, blurred vision, and nausea. Closed-angle glaucoma is an emergency requiring immediate attention.^[1]

If treated early, it is possible to slow or stop the progression of glaucoma. Regular eye examinations, especially if the person is over 40 or has a family history of glaucoma, are essential for early detection.^[8] Treatment typically includes prescription of eye drops, medication, laser treatment or surgery.^[1][9] The goal of these treatments is to decrease eye pressure.^[2]

Glaucoma is the leading cause of blindness in African Americans, Hispanic Americans,^[10][11] and Asians.^[12] It occurs more commonly among older people,^[1] and closed-angle glaucoma is more common in women.^[2]