Hyphaema Health Dictionary

Inability to see. Definitions of blindness and partial sight vary. In the , blindness is defined as a corrected visual acuity of 3/60 or less in the better eye, or a visual field of no more than 20 degrees in the better eye. Blindness may result from injury to, or disease or degeneration of, the eyeball; the optic nerve or nerve pathways connecting the eye to the brain; or the brain itself. Clouding of the cornea may result from Sjögren’s syndrome, vitamin A deficiency, chemical damage, infections, and injury. Corneal ulcers can cause blindness due to scarring of the cornea. Uveitis and cataracts are other common causes of blindness. Diabetes mellitus, hypertension, or injury can all cause bleeding into the cavity of the eyeball and subsequent loss of vision. Bleeding into the fluid in front of the lens (hyphaema) or behind the lens (vitreous haemorrhage) can also result in loss of vision. Other conditions that may cause blindness include glaucoma; retinal artery occlusion or retinal vein occlusion; age-related macular degeneration; retinopathy; retinal detachment; tumours such as retinoblastoma and malignant melanoma of the eye; and retinal haemorrhage.

Loss of vision may be due to nerve conduction problems. These problems may be the result of pressure caused by a tumour; reduced blood supply to the optic nerve; optic neuritis; or toxic or nutritional deficiencies. Blindness can result if there is pressure on the visual cortex from a brain tumour or brain haemorrhage, or if the blood supply to the cortex is reduced following a stroke.

Treatment depends on the underlying cause. If the loss of vision cannot be corrected, the patient may then be registered as legally blind or partially sighted. (See also eye; vision, loss of.)... blindness

Serious eye injuries may be caused either by penetration of the eye by a foreign body (see eye, foreign body in) or by a blow to the eye.

A blow to the eye may cause tearing of the iris or the sclera, with collapse of the eyeball and possible blindness. Lesser injuries may lead to a vitreous haemorrhage, hyphaema, retinal detachment, or injury to the trabeculum (the channel through which fluid drains from inside the eye), which can lead to glaucoma. Injuries to the centre of the cornea impair vision by causing scarring. Damage to the lens may cause a cataract to form.... eye injuries

Inability to see. This may develop slowly or suddenly and may be temporary or permanent, depending on the cause. Vision loss may affect 1 or both eyes. It can cause complete blindness or may affect only peripheral, or only central, vision.

Progressive loss of visual clarity is common with advancing age and may be due to a number of disorders (see vision, disorders of).

Sudden loss of vision may be caused by disorders such as hyphaema, severe uveitis, vitreous haemorrhage, or retinal haemorrhage.

Optic neuritis can reduce vision in 1 eye.

Damage to the nerve connections between the eyes and brain, or to the visual area of the brain, can cause loss of peripheral vision and may be a result of embolism, ischaemia, tumour, inflammation, or injury.... vision, loss of

*uveitis associated with *glaucoma and *hyphaema. This is an uncommon inflammatory condition occurring as a complication of intraocular lens *implants.... ugh syndrome