Eye Disease Definitions
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Age Related Macular Degeneration
This is a disease associated with aging that gradually destroys sharp, central vision. Central vision is needed for seeing objects clearly and for common daily tasks such as reading and driving. AMD affects the macula, the part of the eye that allows you to see fine detail. AMD causes no pain.
Amblyopia
The brain and the eye work together to produce vision. Light enters the eye and is changed into nerve signals that travel along the optic nerve to the brain. Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye.
Anophthalmia and Microphthalmia
Anophthalmia and microphthalmia are often used interchangeably. Microphthalmia is a disorder in which one or both eyes are abnormally small, while Anophthalmia is the absence of one or both eyes. These rare disorders develop during pregnancy and can be associated with other birth defects.
Behcet’s Disease of the Eye
Behcet’s disease is an autoimmune disease that results from damage to blood vessels throughout the body, particularly veins. In an autoimmune disease, the immune system attacks and harms the body’s own tissues. This is also known as Adamantiades. The exact cause is unknown. It is believed that an autoimmune reaction may cause blood vessels to become inflamed, but it is not clear what triggers this reaction.
Bietti’s Crystalline Dystrophy
Bietti’s Crystalline Dystrophy (BCD) is an inherited eye disease that is a rare and appears to be more common in people with Asian ancestry. People with BCD have crystals in some of their white blood cells (lymphocytes) that can be seen by using an electron microscope. Researchers have been unable to determine exactly what substance makes up these crystalline deposits. Their presence does not appear to harm the patient in any other way except to affect vision.
Blepharitis
Blepharitis is a common condition that causes inflammation of the eyelids. The condition can be difficult to manage because it tends to recur. Anterior blepharitis affects the outside front of the eyelid, where the eyelashes are attached. THe two skin disorders can cause this form of blepharitis: acne rosacea, which leads to red and inflamed skin, and scalp dandruff (seborrheic dermatitis).
Blepharospasm
Blepharospasm is associated with an abnormal function of the basal ganglion from an unknown cause. The basal ganglion is the part of the brain responsible for controlling the muscles. In rare cases, heredity may play a role in the development of blepharospasm. Most people develop blepharospasm without any warning symptoms.
Cataract
A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery.A cataract can occur in either or both eyes. It cannot spread from one eye to the other.
Corneal Disease
The cornea is the eye’s outermost layer. It is the clear, dome-shaped surface that covers the front of the eye. The refractive process is similar to the way a camera takes a picture. The cornea and lens in the eye act as the camera lens. The retina is similar to the film. If the image is not focused properly, the film (or retina) receives a blurry image.
Diabetic Retinopathy
Diabetic eye disease refers to a group of eye problems that people with diabetes may face as a complication of diabetes. All can cause severe vision loss or even blindness. Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. It is caused by changes in the blood vessels of the retina.
Floaters
Floaters are little “cobwebs” or specks that float about in your field of vision. They are small, dark, shadowy shapes that can look like spots, thread-like strands, or squiggly lines. They move as your eyes move and seem to dart away when you try to look at them directly. They do not follow your eye movements precisely, and usually drift when your eyes stop moving.
Glaucoma
Glaucoma is a group of diseases that can damage the eye’s optic nerve and result in vision loss and blindness. Glaucoma occurs when the normal fluid pressure inside the eyes slowly rises. However, with early treatment, you can often protect your eyes against serious vision loss.
Histoplasmosis
Histoplasmosis is a disease caused when airborne spores of the fungus Histoplasma capsulatum are inhaled into the lungs, the primary infection site. This microscopic fungus, which is found throughout the world in river valleys and soil where bird or bat droppings accumulate, is released into the air when soil is disturbed by plowing fields, sweeping chicken coops, or digging holes.
Macular Hole
A macular hole is a small break in the macula, located in the center of the eye’s light-sensitive tissue called the retina. The macula provides the sharp, central vision we need for reading, driving, and seeing fine detail. A macular hole can cause blurred and distorted central vision. Macular holes are related to aging and usually occur in people over age 60.
Macular Pucker
A macular pucker is scar tissue that has formed on the eye’s macula, located in the center of the eye’s light-sensitive tissue called the retina. The macula provides the sharp, central vision we need for reading, driving, and seeing fine detail. A macular pucker can cause blurred and distorted central vision.
Refractive Errors
Refractive errors include myopia, hyperopia, presbyopia, and astigmatism, eye conditions that are very common. Most people have one or more of them. Refractive errors can usually be corrected with eyeglasses or contact lens.
Retinal Detachment
The retina is the light-sensitive layer of tissue that lines the inside of the eye and sends visual messages through the optic nerve to the brain. When the retina detaches, it is lifted or pulled from its normal position. If not promptly treated, retinal detachment can cause permanent vision loss.
Retinopathy of Prematurity (ROP)
Retinopathy of prematurity (ROP) is a potentially blinding eye disorder that primarily affects premature infants weighing about 2 1/4 pounds (1250 grams) or less that are born before 31 weeks of gestation (A full-term pregnancy has a gestation of 38-42 weeks). The smaller a baby is at birth, the more likely that baby is to develop ROP. This disorder which usually develops in both eyes is one of the most common causes of visual loss in childhood and can lead to lifelong vision impairment and blindness.
Stargardt
Stargardt disease is the most common form of inherited juvenile macular degeneration. It is characterized by a reduction of central vision with a preservation of peripheral (side) vision.
Usher Syndrome
Usher syndrome is an inherited condition that causes 1) a serious hearing loss that is usually present at birth or shortly thereafter and 2) progressive vision loss caused by retinitis pigmentosa (RP). RP is a group of inherited diseases that cause night-blindness and peripheral (side) vision loss through the progressive degeneration of the retina, the light-sensitive tissue at the back of the eye that is crucial for vision.
Vitreous Detachment
Most of the eye’s interior is filled with vitreous, a gel-like substance that helps the eye maintain a round shape. There are millions of fine fibers intertwined within the vitreous that are attached to the surface of the retina, the eye’s light-sensitive tissue. As we age, the vitreous slowly shrinks, and these fine fibers pull on the retinal surface. Usually the fibers break, allowing the vitreous to separate and shrink from the retina.