Rare, inherited vision disorder in which a person has little or no ability to see colour. People with Achromatopsia also commonly experience some vision loss, especially in bright light, to which they are extremely sensitive. The severity varies. Although there is no cure or treatment for this disorder, people with Achromatopsia can manage its symptoms. For example, they can wear sunglasses or tinted contact lenses to cope with bright light.
A hereditary condition characterised by a variable lack of pigment in the eyes, skin, or hair. People with Albinism may have pale pink skin and blonde to white hair, but there are different types of Albinism, and the amount of pigment varies. The irises of their eyes may be white or pinkish. They are sensitive to bright light and glare and commonly have other vision problems. While some people with Albinism can see well enough to drive, many have impaired vision or may even be legally blind. Bifocals, magnifiers, tinted lenses and other optical devices can help people with Albinism.
A condition in which a person’s vision does not develop properly in early childhood because the eye and the brain are not working together correctly. Amblyopia, which usually affects only one eye, is also known as “lazy eye.” A person with amblyopia experiences blurred vision in the affected eye. Early treatment is advisable, because if left untreated, this condition may lead to permanent vision problems. Treatment options include vision therapy exercises or prescription eyeglasses. People with amblyopia may need to wear an eye patch over their stronger eye in order to force the affected eye to function as it should.
Partial or complete absence of the iris of the eye. This rare condition, usually present at birth, results in impaired vision and sensitivity to light. People with aniridia are also at high risk for certain other eye conditions, People with aniridia may benefit from wearing tinted contact lenses or sunglasses, using magnifiers, and avoiding intense or glaring light.
A rare condition in which one or both eyes do not form during pregnancy. There is no cure for anopthalmia. Prosthetic eyes can promote proper growth of the eye sockets and development of facial bones and also serve cosmetic purposes.
Absence of the lens of the eye, usually associated with the surgical removal of a cataract but may also result from a wound or other cause. Without the lens, the eye cannot adjust its focus for seeing at different distances. Contact lenses or eyeglasses are used to correct the vision. In cataract surgery, an artificial lens is inserted to replace the lens removed. A person with Aphakia will benefit from good, but not excessive, lighting and high-contrast reading materials.
Common condition, usually present from birth, caused by an irregularly curved cornea or lens. People with astigmatism may experience blurred vision, eyestrain, or headaches. Astigmatism can be corrected with eyeglasses or contact lenses. Corrective surgery is another option.
Rare, inherited condition that affects the macula, the area in the middle of the retina, and can cause blurred or distorted vision or a loss of central vision. Best’s Disease may affect both eyes. The disease’s effects on sight vary and may not become severe for many years, if ever. Most people are not significantly affected until after age 40. There is no treatment for Best’s Disease.
Birdshot uveitis is a rare, auto-immune, potentially blinding and chronic form of posterior uveitis. Uveitis means inflammation of the uvea, part of the eye that is made up of the iris, choroid of the eye and ciliary body. Symptoms include floaters blurred vision, night blindness, sensitivity to lights and shimmering vision. The disease is called birdshot because the spots resemble the pattern seen when you fire birdshot pellets from a shotgun.
Blepharitis is an inflammation of the eyelids causing red, sore and itchy eyes. It generally does not cause any damage to eyesight. There are two types of blepharitis, Anterior (occurs on the outside front edge of the eyelid where the eyelashes are) and Posterior (occurs on the inside edge of the eyelid that touches the eye’s surface).
A condition in which the lens of the eye becomes cloudy or opaque. Cataracts generally form slowly and without pain. They can affect one or both eyes. Over time, a cataract may interfere with vision, causing images to appear blurred or fuzzy and colours to seem faded. Most cataracts are related to aging. Cataracts affect more than 50 percent of all adults by age 80 and are the primary cause of vision loss in people 55 and older. People with early cataract may benefit from new eyeglasses, bright lighting, anti-glare sunglasses, or magnifying lenses. Surgery is the only effective treatment, which is common and involves removal of the cloudy lens and replacement with an artificial lens.
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Charles Bonnet syndrome
Visual disturbances usually occurring in people who have experienced visual impairment or sight loss later in life. People with Charles Bonnet syndrome may see a wide range of images, from simple patterns to people, animals, and buildings. The visual disturbances associated with this syndrome are not signs of mental illness, and people realise that the images they are seeing are not real. There is no cure for Charles Bonnet syndrome. However, the symptoms often stop on their own. Organise a consult with an eye care specialist because treatment for vision disorders may help.
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Rare disorder that causes progressive loss of the choroid, an important layer under the retina that is responsible for some of its blood supply. Choroideremia is an inherited disorder that generally affects males only. It commonly begins as night blindness in childhood and gradually advances to increasing vision loss. Most people with this disorder are able to retain good vision until age 40 or 50. There is no treatment but people who have the disorder may find it helpful to use optical, electronic, or computer-based devices for low vision.
Symptoms typically begin as blurred vision, usually pronounced when one eye is closed. Flashes of light and floaters are common symptoms. Persistent colour patterns may also be perceived in the affected eye. One early warning sign of Coats’ disease is yellow-eye in flash photography. Just as the red-eye effect is caused by a reflection of blood vessels in the back of a normal eye, an eye affected by Coats’ will glow yellow in photographs as light reflects off cholesterol deposits. Children with yellow-eye in photographs are typically advised to immediately seek evaluation from any optometrist or ophthalmologist. Coats’ disease itself is painless.
A cleft or gap in some part of the eye, such as the iris, lens, or retina, that is caused by a defect in the development of the eyeball. How much Coloboma affects a person’s vision depends on the size and location of the cleft and on whether it occurs in one or both eyes. A person with large defects in the retina and optic nerve may have limited vision. Children whose vision is impaired by Coloboma may benefit from using reading materials that have large black print and well-spaced letters and words.
Colour blindness is an inherited condition which is characterised by an inability to distinguish between certain colours, usually red and green, but some people confuse red and blue, seeing them as various shades of brown or grey. Colour blindness usually affects males and situations in which colours are important may become hazardous. It is not really a form of blindness, but rather a deficiency in colour perception. There is no treatment or cure for colour blindness as it is hereditary.
An inherited disease that, over time, causes deterioration of the specialised light-sensitive cells of the retina. People with cone-rod dystrophy typically experience decreased sharpness of vision followed by a loss of peripheral vision and colour perception. The most common form of cone-rod dystrophy is retinitis pigmentosa. There is no treatment or cure for this disease, which is also referred to as cone-rod degeneration, progressive cone-rod dystrophy, and retinal cone dystrophy.
Conjunctivitis is Inflammation of the conjunctiva. Conjunctivitis is a term that covers several different eye diseases. Literally the word means an inflammation of the outer surface of the eye. The inflammation is usually accompanied by pain or an itch, redness of the eye and often a discharge.
The most common form of conjunctivitis is caused by a bacterial infection of the thin film of tears that covers the eye. The bacteria can sometimes be infectious.
Bacterial conjunctivitis is characterised by yellow pus that forms in the eyes and may stick the eyelids together during sleep. The eyes are bloodshot and may be a little sore. It almost invariably involves both eyes.
Babies who develop recurrent attacks of bacterial conjunctivitis may be suffering from a blocked tear duct as well. Tears are produced in a small gland beyond the outer edge of the eye. They move across the surface of the eye and through a tiny tube at the inner edge of the eye, ending in the nose. If an infant’s duct is too small, or is blocked by pus, the circulation of tears is prevented and infection results.
A blocked tear duct may be probed and cleared by a doctor if the conjunctivitis persists for several months, but most babies grow out of the problem.
Viral conjunctivitis is the most difficult to treat but some types that infect the eye surface can be controlled by anti-viral drops.
The effects of corneal disease vary. Some corneal conditions cause few, if any, vision problems. For example, infections of the cornea can often be treated with antibiotics. However, if the cornea becomes cloudy, light cannot penetrate the eye to reach the retina, and severe visual impairment, or even blindness, may result. Corneal dystrophies are usually inherited conditions in which one or more parts of the cornea lose their clarity due to a build-up of cloudy material. When corneal disease causes the cornea to become permanently clouded or scarred, doctors may be able to restore vision with a corneal transplant—surgical replacement of the old cornea with a new one.
Cortical Visual Impairment
Visual impairment caused by damage to those parts of the brain related to vision. The eye is normal but the brain cannot properly process the information it receives. The degree of vision loss may be mild or severe and can vary greatly, even from day to day. Cortical visual impairment can be temporary or permanent. People with cortical visual impairment have difficulty using what their eye sees. For example, they may have trouble recognizing faces, interpreting drawings, perceiving depth, or distinguishing between background and foreground. Children with cortical visual impairment are often able to see better when told in advance what to look for.