Eye diseases

A cataract is a cloudy area in the lens of the eye that impairs vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colours, blurry or double vision, halos around light, trouble with bright lights, and difficulty seeing at night. This may result in difficulty driving, reading and recognizing faces. Poor vision caused by cataracts may also result in an increased risk of falling and depression. In 2020 Cataracts caused 39.6% of all cases of blindness and 28.3% of visual impairment worldwide. Cataracts remain the single most common cause of global bl

Conjunctivitis, also known as pink eye, is inflammation of the conjunctiva, the thin and clear layer that covers the white surface of the eye and the inner eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may occur. The affected eye may have increased tears or be stuck shut in the morning. Swelling of the sclera may also occur. Itching is more common in cases that are due to allergies. Conjunctivitis can affect one or both eyes.

decreased ability to see

Nystagmus is a condition of involuntary (or voluntary, in some cases) eye movement. People can be born with it but more commonly acquire it in infancy or later in life. In many cases it may result in reduced or limited vision.

Heterochromia is a variation in coloration most often used to describe color differences of the iris, but can also be applied to color variation of hair or skin. Heterochromia is determined by the production, delivery, and concentration of melanin (a pigment). It may be inherited, or caused by genetic mosaicism, chimerism, disease, or injury. It occurs in humans and certain breeds of domesticated animals.

Keratoconus is an eye disorder in which the cornea, the transparent front part of the eye, gradually thins and bulges outward into a cone shape. This causes distorted vision, including blurry vision, double vision, increased nearsightedness, irregular astigmatism, and light sensitivity, which can reduce quality of life. Both eyes are usually affected.

disease characterized by miosis (a constricted pupil), partial ptosis (a weak, droopy eyelid), apparent anhydrosis (decreased sweating), with apparent enophthalmos (inset eyeball)

human disease

Anisocoria is a condition characterized by an unequal size of the eyes' pupils. Affecting up to 20% of the population, anisocoria is often entirely harmless, but can be a sign of more serious medical problems.

medical condition

health condition negatively affecting the eye

A coloboma (from the Greek , meaning "defect") is a hole in one of the structures of the eye, such as the iris, retina, choroid, or optic disc. The hole is present from birth and can be caused when a gap called the choroid fissure, which is present during early stages of prenatal development, fails to close up completely before a child is born. Ocular coloboma is relatively uncommon, affecting less than one in every 10,000 births.

Human disease

condition resulting from focusing the eyes on a screen for protracted, uninterrupted periods of time

age related macular degeneration that is characterized by progressive vision loss usually to the point of legal blindness

ciliopathic human genetic disorder that produces many effects and affects many body systems

tissue disease

rare genetic disorder affecting collagen

type of eye disease

human disease

symptom of human disease

scratch to the surface of the cornea of the eye

Hypertelorism is an abnormally increased distance between two organs or bodily parts, usually referring to an increased distance between the orbits (eyes), or orbital hypertelorism. In this condition, the distance between the inner eye corners, as well as the distance between the pupils, is greater than normal. Hypertelorism should not be confused with telecanthus, in which the distance between the inner eye corners is increased, but the distances between the outer eye corners and the pupils remain unchanged.

Hypopyon is a medical condition involving inflammatory cells in the anterior chamber of the eye.

Chemosis is the swelling (or edema) of the conjunctiva (the lining of the white of the eye). The term derives from , meaning , due to the swollen conjunctiva resembling it, and , meaning . The swelling is due to the oozing of exudate from abnormally permeable capillaries. In general, chemosis is a nonspecific sign of eye irritation. The outer surface covering appears to have fluid in it. The conjunctiva becomes swollen and gelatinous in appearance. Often, the eye area swells so much that the eyes become difficult or impossible to close fully. Sometimes, it may also appear as if the iris has mo

Photopsia is the presence of perceived flashes of light in the field of vision.

thyroid eye disease often associated with Graves' disease

Endophthalmitis, or endophthalmia, is inflammation of the interior cavity of the eye, usually caused by an infection. It is a possible complication of all intraocular surgeries, particularly cataract surgery, and can result in loss of vision or loss of the eye itself. Infection can be caused by bacteria or fungi, and is classified as exogenous (infection introduced by direct inoculation as in surgery or penetrating trauma), or endogenous (organisms carried by blood vessels to the eye from another site of infection and is more common in people who have an immunocompromised state). Other non-inf

painless temporary loss of vision in one or both eyes

multisystem disease

eye infection shortly after birth

condition of the eye in which the vitreous membrane separates from the retina

small, white or grayish/brown spots on the periphery of the iris in the human eye

cranial nerve disease that is located in the optic nerve

Keratomalacia is an eye disorder that results from vitamin A deficiency. Vitamin A is required to maintain specialized epithelia (such as in the cornea and conjunctiva).

a rare vasculitis of children and young adults characterized by nonsyphilitic interstitial keratitis of cornea, fever and fatigue.

Ophthalmia (; also called ophthalmitis, and archaically obtalmy) is inflammation of the eye. It results in congestion of the eyeball, often eye-watering, redness and swelling, itching and burning, and a general feeling of irritation under the eyelids. Ophthalmia can have different causes, such as infection from bacteria, viruses, fungi, or may result from a physical trauma to the eye, chemical irritation, and allergies. A bacterial infection can result in a mucus and pus secretion. Severe cases of ophthalmia can cause blindness if not treated, especially in newborns, who contract it from the e

medical condition

Leukocoria (also white pupillary reflex) is an abnormal white reflection from the retina of the eye. Leukocoria resembles eyeshine, but leukocoria can also occur in animals that lack eyeshine because their retina lacks a tapetum lucidum.

buildup of keratin located superficially in the conjunctiva

Amaurosis (Greek meaning darkening, dark, or obscure) is vision loss or weakness that occurs without an apparent lesion affecting the eye. It may result from either a medical condition or excess acceleration, as in flight. The term is the same as the Latin gutta serena, which means, in Latin, clear drop (or bright drop). Gutta serena is a condition of partial or complete blindness with a transparent, clear pupil. This term contrasts with suffusio nigra which means, in Latin, dark suffusion, indicating partial or complete blindness with a dark pupil, e.g., a cataract. John Milton, already total

Micropsia is a condition affecting human visual perception in which objects are perceived to be smaller than they actually are. Micropsia can be caused by optical factors (such as wearing glasses), by distortion of images in the eye (such as optically, via swelling of the cornea or from changes in the shape of the retina such as from retinal edema, macular degeneration, or central serous retinopathy), by changes in the brain (such as from traumatic brain injury, epilepsy, migraines, or drugs), and from psychological factors. Dissociative phenomena are linked with micropsia, which may be the re

Human disease

Human disease

medical sign observed during an eye test

autosomal genetic disease characterized by short stature, brachycephaly and other facial abnormalities, brachydactyly, joint stiffness and distinctive ocular abnormalities

disorder of the nictitating membrane (NM), also called the third eyelid, present in the eyes of dogs and cats

type of hallucination

Buphthalmos (plural: buphthalmoses) is enlargement of the eyeball and is most commonly seen in infants and young children. It is sometimes referred to as buphthalmia (plural buphthalmias). It usually appears in the newborn period or the first 3 months of life. and in most cases indicates the presence of congenital (infantile) glaucoma, which is a disorder in which elevated pressures within the eye lead to structural eye damage and vision loss.

thumb|Diagram showing the definition of telecanthus, or dystopia canthorum

Eales disease (ED) is an idiopathic, inflammatory retinal venous occlusive disease characterized by 3 stages: vasculitis, occlusion and retinal neovascularization, leading to recurrent vitreous hemorrhages and vision loss

thumb|alt=A man with his back to the camera stares directly at a twilight sun.|A man sungazing

Hypotelorism is an abnormally decreased distance between two organs or bodily parts, usually pertaining to the eye sockets (orbits), also known as orbital hypotelorism.

disorder of lipoprotein metabolism

syndrome that occurs when tiny flakes of dandruff-like material build up in the body and are found in the heart, kidneys, liver, lungs, and eye

Panophthalmitis is the inflammation of all coats of the animal eye including intraocular structures. It can be caused by infection, particularly from Pseudomonas species, such as Pseudomonas aeruginosa, Clostridium species, Whipple's disease, and also fungi. It can also be caused by other stress.

degeneration of the macula

thumb|Macular hard drusen and hard exudates in the right eye of a 65-year-old diabetic woman

Human disease