Glaucoma of the hyaloid canal and the tunica vasculosa lentis is associated with other anomalies. Angle closure-induced ocular hypertension and glaucomatous optic neuropathy may also occur with these anomalies, and has been modelled in mice. Other factors can cause glaucoma, known as "secondary glaucoma", including prolonged use of steroids (steroid-induced glaucoma); conditions that severely restrict blood flow to the eye, such as severe diabetic retinopathy and central retinal vein occlusion (neovascular glaucoma); ocular trauma (angle-recession glaucoma); and inflammation of the middle layer of the pigmented vascular eye structure (uveitis), known as uveitic glaucoma. The underlying cause of open-angle glaucoma remains unclear.
Glaucoma 2 million people in the United States. It occurs more commonly among older people. Closed-angle glaucoma is more common in women. Glaucoma has been called the "silent thief of sight" because the loss of vision usually occurs slowly over a long period of time. Worldwide, glaucoma is the second-leading cause of blindness after cataracts. The word "glaucoma" is from Ancient Greek "glaukos" which means blue, green, or gray. In English, the word was used as early as 1587 but did not become commonly used until after 1850, when the development of the ophthalmoscope allowed people to see the optic nerve