A-Z (Eye conditions and diseases)
Age-Related Macular Degeneration
Age-related macular degeneration is an eye condition that leads to the deterioration of the center of the retina, called the macula, leading to loss of central vision.
The human immunodeficiency virus (HIV) is a virus that causes the body’s immune system to break down, leading to illness from infections. HIV and AIDS affect the eye by making the eyes susceptible to infection.
Albinism is a group of hereditary conditions that affect how the body produces or distributes pigment. People with albinism have a reduced amount or absence of pigment in their eyes, hair and skin.
Eye allergies are a condition when the eyes react to an irritant or allergen, making them red, itchy, tearful and swollen. Amblyopia (Lazy Eye)
Lazy eye is poor vision in an eye that did not develop normal sight during childhood. Lazy eye is also called amblyopia.
Anisocoria is when your pupils are different sizes.
Astigmatism is an imperfection in the curvature of your cornea — the clear, round dome covering the eye’s iris and pupil — or in the shape of the eye’s lens, causing blurry or distorted vision.
Bacterial keratitis is an infection of the cornea, often due to improper care and cleaning of contact lenses or from injury to the cornea.
Bell's palsy is a temporary condition that causes certain muscles in your face to weaken or become paralyzed.
A black eye is bruising around the eye due to an injury to the face or head.
Blepharitis is inflammation (swelling) of the eyelids, where the upper and lower eyelids become coated with oily particles and bacteria near the base of the eyelashes. Blepharitis causes irritation, itchiness, redness, and stinging or burning of the eye.
Blocked tear duct
A blocked tear duct is when the eye’s drainage system for tears is either partially or completely obstructed. Tears cannot drain normally, causing a watery, irritated or chronically infected eye.
Branch Retinal Vein Occlusion (BRVO)
Branch retinal vein occlusion (BRVO) is a blockage of the small veins in the retina.
Cataract is a clouding of the eye’s normally clear lens, causing vision problems. Cellulitis Cellulitis is a bacterial infection of tissue that can affect both the eyes and skin.
Central Retinal Vein Occlusion (CRVO)
CRVO is a blockage of the main vein in the retina.
Central Serous Retinopathy
In central serous retinopathy, fluid builds up under the retina and distorts vision.
Chalazion and Stye
A chalazion is a lump on the eyelid caused by enlarged oil-producing gland in the eyelid. A stye is also a lump on the eyelid, usually caused by an infected eyelash follicle.
Choroidal Neovascular Membranes
In the eye, a healthy, intact retina is key to clear vision. Choroidal neovascular membranes (CNVM) are new blood vessels that grow beneath the retina and disrupt vision. CNVM are associated with many serious eye diseases.
A coloboma describes conditions where normal tissue in or around the eye is missing from birth.
Color blindness occurs when you are unable to see colors in a normal way. Most commonly, color blindness happens when someone cannot distinguish between certain colors, usually between greens and reds, and occasionally blues.
Conjunctivitis (Pink Eye)
Conjunctivitis is swelling of the conjunctiva — the thin, filmy membrane that covers the inside of your eyelids and the white part of your eye (sclera).
Contact Lens-Related Eye Infections
The most common infection related to contact lens use is keratitis, an infection of the cornea (the clear, round dome covering the eye's iris and pupil).
Corneal abrasion is a scratch or scrape on the eye’s cornea.
Corneal dystrophies are a group of relatively rare genetic eye disorders in which abnormal material often accumulates in the cornea.
Corneal erosion affects the cornea, the clear dome covering the front of the eye. The outermost layer of the cornea is the epithelium. When the epithelium does not stay attached correctly to the corneal tissue below, this can cause a condition called corneal erosion.
Corneal laceration is a cut on the cornea.
A corneal ulcer is an open sore on the cornea.
Cytomegalovirus retinitis (CMV retinitis) is a serious viral eye infection of the retina, the light-sensing nerve layer that lines the back of the eye. It is most often found in people with compromised immune systems.
Diabetic retinopathy is a common diabetic eye disease caused by changes in retinal blood vessels.
Dilating eyedrops (called mydriatics) are used to dilate, or enlarge, the pupils of your eyes so that your eye doctor can see the inside of your eye in detail.
Drusen are yellow deposits under the retina. While drusen likely do not cause age-related macular degeneration (AMD), their presence increases a person’s risk of developing AMD.
Dry eye is a condition where the eyes don’t produce enough tears or the right quality of tears to be healthy or comfortable.
Cancer of the eye is a malignancy that starts and grows in your eye. A malignancy is a group of cells that are cancerous and that can spread to other sites in the body or invade and destroy tissues.
Primary intraocular lymphoma (PIOL) involves the retina, vitreous and optic nerve. Eighty percent of cases involve both eyes; many people with PIOL will develop lymphoma within the part of the brain called the cerebrum.
Hyperopia (farsightedness) is a refractive error, which means the eye does not bend or refract light properly. With hyperopia, distant objects look clear but close objects appear blurred.
Floaters and Flashes
Floaters are shadows cast on the eye’s retina from clumps of gel or cells inside the vitreous. Flashes are flashes of light that you see when the vitreous gel pulls or rubs the retina.
Fuchs’ dystrophy is a progressive eye disease affecting the cornea, causing certain cells to deteriorate and die off, making corneal cells swollen and cloudy.
Fungal keratitis is an infection of the cornea, often due to improper care and cleaning of contact lenses or from injury to the cornea.
Giant Cell Arteritis
Giant cell arteritis (GCA) is a swelling of the arteries, which are the blood vessels that carry blood away from the heart. When arteries swell, it reduces the blood flow through these vessels. GCA affects the arteries in the neck, upper body and arms. Because these blood vessels also help nourish your eyes, reduced blood flow can cause sudden, painless vision loss.
Glaucoma is a disease that damages the eye’s optic nerve.
Graves' disease is an autoimmune disorder that leads to over activity of the thyroid gland. The gland produces hormones that regulate your body’s metabolism. When Graves’ disease affects the eyes, the condition is known as thyroid eye disease.
Hemangioma is a non-cancerous tumor caused by abnormal growth of blood vessels. Hemangiomas can occur anywhere on the body, but are most commonly found on the face and neck. While they can be present at birth, hemangiomas more often appear during the first six months of life.
Herpes keratitis is a viral infection of the eye caused by the herpes simplex virus (HSV). Type I HSV is the most frequent cause of eye infections. Herpes Zoster (Shingles) The virus varicella zoster causes two distinct diseases: chicken pox and, if reactivated later in life, herpes zoster, more commonly called shingles.
Histoplasmosis is a disease caused when airborne fungus spores are inhaled into the lungs. Histoplasmosis initially is a lung infection. However, it is believed that the infection, even if mild, can later migrate to the eye through the blood stream and cause a serious eye disease called ocular histoplasmosis syndrome (OHS).
A hyphema is a collection of blood in the front part of the eye.
Iridocorneal Endothelial Syndrome
Iridocorneal endothelial syndrome (ICE) is a rare group of conditions whose three main features include swelling of the cornea, changes in the iris, and a form of glaucoma.
Ischemic Optic Neuropathy
Ischemic optic neuropathy (ION) is a sudden loss of central vision, side vision or both due to a decreased or interrupted blood flow to the eye’s optic nerve. Some ophthalmologists may describe ischemia of the optic nerve as a stroke at the back of the eye.
Juvenile Macular Degeneration
Juvenile macular degeneration is a series of inherited eye disorders that affects children and young adults. The most common form of juvenile macular degeneration is Stargardt disease. Other types of juvenile macular degeneration include Best’s disease and juvenile retinoschisis. All of these diseases are rare and cause central vision loss.
Keratitis is a condition where the cornea becomes swollen or inflamed, making the eye red and painful and affecting vision.
Keratoconus is a condition when the normally round cornea becomes thin and develops a cone-like bulge.
Low vision is a loss of eyesight that makes everyday tasks difficult or impossible, affecting central and/or peripheral (side) vision. Low vision cannot be improved with regular eyeglasses, medicine or surgery.
Macular edema is a swelling or thickening of the macula, the area of the retina responsible for central vision.
Macular hole is a small break in the macula, the central area of the retina that is responsible for central vision.
A macular pucker is when the macula—part of the eye’s retina—wrinkles, creases or bulges, leading to blurry or distorted vision and possibly a blind spot in your visual field.
Macular telangiectasia is a disease affecting the macula, causing loss of central vision. The macula is a small area in the retina that is responsible for your central vision. Macular telangiectasia develops when there are problems with the tiny blood vessels around the fovea, the center of the macula.
Marfan syndrome is a genetic condition that affects the body’s connective tissue. Marfan syndrome can affect many different parts of the body, including the eyes.
Microvascular Cranial Nerve Palsy
Microvascular cranial nerve palsy (MCNP) is a neurological condition that affects the muscles that move the eyes, causing inability to move the eyes in certain directions, double vision and sometimes a droopy eyelid.
Classic migraine starts with visual symptoms such as zigzag lines, colored lights or flashes of light expanding to one side of your vision over 10 to 30 minutes, followed by a single-sided pounding, severe headache. Along with the headache, you may have nausea, vomiting and light sensitivity. Common migraine may cause only a headache felt on both sides of the head.
Mohs surgery is a procedure used to remove skin cancer. Because the surgery removes only tissue with cancer cells, it is commonly used on areas of the body where it is important to minimize the removal of healthy tissue. For the eye area, Mohs surgery is used to remove basal cell and squamous cell cancers found on the eyelids or around the eyes, and sometimes to remove melanoma.
Myasthenia gravis is a chronic autoimmune disorder that causes muscles to weaken and tire easily. Most people affected by myasthenia gravis develop “ocular myasthenia” first, where the muscles that control eye and eyelid movement are affected, causing eyelid drooping, blurry vision or double vision.
Myopia (nearsightedness) is a refractive error, which means the eye does not bend or refract light properly. With myopia, close objects look clear but distant objects appear blurred.
A nevus (plural, nevi) in the eye is a common, benign, pigmented growth, similar to a mole on your skin.
Nystagmus is an involuntary, rapid and repetitive movement of the eyes — either side-to-side, up and down or vertical.
Ocular hypertension is when the pressure inside the eye (intraocular pressure) is higher than normal. Unlike glaucoma, with ocular hypertension the optic nerve appears normal and no signs of glaucoma are found during visual field testing, which tests side (peripheral) vision.
Ocular melanoma (also called eye melanoma) is a type of cancer that develops in the cells that produce pigment — the substance that gives your skin, hair and eyes color.
Optical Coherence Tomography
Optical coherence tomography (OCT) is a non-invasive imaging test that uses light waves to take cross-section pictures of your retina. With OCT, each of the retina’s distinctive layers can be seen, allowing your ophthalmologist to map and measure their thickness.
Optic neuritis is an inflammation of the eye’s optic nerve.
Photokeratitis is a painful eye condition that occurs when your eye is exposed to invisible rays of energy called ultraviolet (UV) rays, either from the sun or from a man-made source. Photokeratitis is like having a sunburned eye.
Pigment Dispersion Syndrome
Pigment dispersion syndrome is a condition in which increased amounts of pigment, the material that gives your iris its color, circulate in other parts of the eye. The tiny granules of pigment can clog your eye’s drainage system, causing eye pressure problems.
Pinguecula and Pterygium
Pinguecula and Pterygium are common, non-cancerous growths on the cornea and conjunctiva likely caused by exposure to ultraviolet (UV) light, dry eye and wind and dust.
Presbyopia is an age-related condition when the eye’s lens doesn’t change shape as easily as it once did, making it more difficult to read or see things at close range.
Ptosis is when the upper eyelid droops, sometimes restricting or blocking vision.
Retinitis pigmentosa is a group of genetic disorders that affect the retina’s ability to respond to light, causing a slow loss of vision.
Retinoblastoma is cancer of the eye that begins in the retina, and is most common among children.
Retinopathy of Prematurity
Retinopathy of prematurity (ROP) is an eye disease that occurs in a small percentage of premature babies where abnormal blood vessels grow on the retina.
Scleritis is a painful swelling of the white part of the eye, which is also known as the sclera. In almost half of all cases, scleritis is associated with an underlying autoimmune disorder such as rheumatoid arthritis. There are two main types of scleritis: anterior and posterior.
Steroid Tablets (Corticosteroids)
Corticosteroids are medications used to treat inflammatory conditions affecting the eye and other parts of the body. Corticosteroids are different from anabolic steroids, which are used sometimes by athletes and bodybuilders to enhance muscle mass. Corticosteroids are found naturally in the body and help regulate blood sugar, salt and water levels, metabolism and growth. They also help to control allergic reactions.
Stickler syndrome is a genetic disorder that affects collagen, the connective tissue of the body. Collagen is a main component of the cornea. People with Stickler syndrome can experience a range of problems, including eye disorders, hearing impairment and joint abnormalities.
Strabismus is a visual problem in which the eyes are not aligned properly and point in different directions. One eye may look straight ahead, while the other eye turns inward, outward, upward or downward.
Most people know that high blood pressure and other vascular diseases pose risks to overall health, but many may not know that high blood pressure can affect vision by damaging the arteries in the eye. A stroke affecting the eye, also known as a retinal artery occlusion, is a blockage in the blood vessels in your retina.
A subconjunctival hemorrhage is a single, concentrated spot of blood, or many scattered blood splotches, under the conjunctiva, a clear membrane that covers the white of the eye (called the sclera) and the inner eyelids.
Torn or Detached Retina
A torn retina is when the retina tears in one or more places. A detached retina is when the retina is lifted off the wall of the back of the eye.
Trachoma, an eye infection affecting both eyes, is the world’s leading cause of preventable blindness. Trachoma is caused by a bacterium called Chlamydia trachomatis. If the infection is untreated, scarring occurs inside the eyelid. This leads to the eyelashes turning inward toward the eye, a condition called trachiasis. The eyelashes brush and scratch against the cornea. This continual irritation turns the cornea cloudy and can lead to the development of corneal ulcers and vision loss.
Trichiasis is a common eyelid abnormality in which the eyelashes are misdirected and grow inwards toward the eye. Those inward-turning lashes rub against the cornea, the conjunctiva and the inner surface of the eyelids, irritating the eye.
Eyelid spasm or twitching, which is also called blepharospasm, is an abnormal, involuntary blinking or spasm of the eyelids.
Usher syndrome is the most common genetic condition that affects both vision and hearing. The major symptoms of Usher syndrome are hearing loss and vision loss from an eye disorder called retinitis pigmentosa, or RP.
Uveitis is inflammation of the uvea, the middle layer of the eye between the retina and the sclera (white of the eye), and can lead to vision loss if left untreated.
Vitamin A Deficiency
A lack of access to a balanced diet with enough vitamin A can lead to vitamin A deficiency. Vitamin A deficiency is the leading cause of preventable blindness in children worldwide. An estimated 250,000 to 500,000 children become blind every year because of vitamin A deficiency.