Glaucoma

Bionic eyes offering better sight to blind

A brighter ray of hope is on the horizon for the blind, as scientists improve electronic hardware that creates sight - making it possible, they predict, to read printed text, recognize faces and lead normal, independent lives.

Feb 15, 2015
popularity 5 / 5 (8) | comments 0

New target for prostate cancer treatment discovered

Keck Medicine of the University of Southern California (USC) scientists have found a promising new therapeutic target for prostate cancer. The findings offer evidence that a newly discovered member of a family ...

Feb 20, 2015
popularity 4.8 / 5 (5) | comments 0

Early retina cell changes in glaucoma identified

Glaucoma, the second leading cause of blindness, usually stems from elevated eye pressure, which in turn damages and destroys specialized neurons in the eye known as retinal ganglion cells. To better understand ...

Feb 11, 2015
popularity 3.7 / 5 (3) | comments 0

Glaucoma is an eye disease in which the optic nerve is damaged in a characteristic pattern. This can permanently damage vision in the affected eye(s) and lead to blindness if left untreated. It is normally associated with increased fluid pressure in the eye (aqueous humour). The term 'ocular hypertension' is used for people with consistently raised intraocular pressure (IOP) without any associated optic nerve damage. Conversely, the term 'normal tension' or 'low tension' glaucoma is used for those with optic nerve damage and associated visual field loss but normal or low IOP.

The nerve damage involves loss of retinal ganglion cells in a characteristic pattern. There are many different subtypes of glaucoma, but they can all be considered to be a type of optic neuropathy. Raised intraocular pressure (above 21 mmHg or 2.8 kPa) is the most important and only modifiable risk factor for glaucoma. However, some may have high eye pressure for years and never develop damage, while others can develop nerve damage at a relatively low pressure. Untreated glaucoma can lead to permanent damage of the optic nerve and resultant visual field loss, which over time can progress to blindness.

Glaucoma can be roughly divided into two main categories, "open angle" and "closed angle" (or "angle closure") glaucoma. The angle refers to the area between the iris and cornea, through which fluid must flow to escape via the trabecular meshwork. Closed angle glaucoma can appear suddenly and is often painful; visual loss can progress quickly, but the discomfort often leads patients to seek medical attention before permanent damage occurs. Open angle, chronic glaucoma tends to progress at a slower rate and patients may not notice they have lost vision until the disease has progressed significantly.

Glaucoma has been called the "silent thief of sight" because the loss of vision often occurs gradually over a long period of time, and symptoms only occur when the disease is quite advanced. Once lost, vision can not normally be recovered and so treatment is aimed at preventing further loss. Worldwide, glaucoma is the second leading cause of blindness after cataracts. It is also the leading cause of blindness among African Americans. Glaucoma affects one in 200 people aged fifty and younger, and one in 10 over the age of eighty. If the condition is detected early enough, it is possible to arrest the development or slow the progression with medical and surgical means.

The word "glaucoma" comes from the Greek γλαύκωμα, "opacity of the crystalline lens." (Cataracts and glaucoma were not distinguished until c.1705).

This text uses material from Wikipedia licensed under CC BY-SA

Latest Spotlight News

A gene for brain size only found in humans

About 99 percent of human genes are shared with chimpanzees. Only the small remainder sets us apart. However, we have one important difference: The brain of humans is three times as big as the chimpanzee ...

Thinking of God makes people bigger risk-takers

Reminders of God can make people more likely to seek out and take risks, according to research published in Psychological Science, a journal of the Association for Psychological Science. The findings sugges ...