Congenital disorders of eyes

eye disease characterized by the drooping or falling of the upper eyelid

Cyclopia (named after the Greek mythology characters cyclopes), also known as alobar holoprosencephaly, is the most extreme form of holoprosencephaly and is a congenital disorder (birth defect) characterized by the failure of the embryonic prosencephalon to properly divide the orbits of the eye into two cavities. Its incidence is 1 in 16,000 in born animals and 1 in 200 in miscarried fetuses.

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.

Entropion is a medical condition in which the eyelid (usually the lower lid) folds inward. It is very uncomfortable, as the eyelashes continuously rub against the cornea causing irritation. Entropion is usually caused by genetic factors. This is different from when an extra fold of skin on the lower eyelid causes lashes to turn in towards the eye (epiblepharon). In epiblepharons, the eyelid margin itself is in the correct position, but the extra fold of skin causes the lashes to be misdirected. Entropion can also create secondary pain of the eye (leading to self trauma, scarring of the eyelid,

Aphakia is the absence of the lens of the eye, due to surgical removal, such as in cataract surgery, a perforating wound or ulcer, or congenital anomaly. It causes a loss of ability to maintain focus (accommodation), high degree of farsightedness (hyperopia), and a deep anterior chamber. Complications include detachment of the vitreous or retina, and glaucoma. Babies are rarely born with aphakia. Occurrence most often results from surgery to remove a congenital cataract. Congenital cataracts usually develop as a result of infection of the fetus or genetic reasons. It is often difficult to iden

Aniridia is a condition characterized by the absence or near absence of the iris, the colored, muscular ring in the eye that controls the size of the pupil and regulates the amount of light entering the eye. This absence results in a primarily black appearance of the central eye. Aniridia can be congenital, typically affecting both eyes, or caused by a penetrant injury. Congenital aniridia is not simply an iris defect but a more complex condition affecting multiple parts of the eye, with macular and optic nerve hypoplasia, cataract, and corneal changes. Vision may be severely compromised and t

thumb|Cycatricial ectropion – closed eyes

thumb|260px|(a) Bilateral anophthalmia. (b) Bilateral microphthalmia. (c) Unilateral anophthalmia with shell (right eye) Anophthalmia (Greek: ἀνόφθαλμος, "without eye") is the medical term for the absence of one or both eyes. Both the globe and the ocular tissue are missing from the orbit. The absence of the eye will cause a small bony orbit, a constricted mucosal socket, short eyelids, reduced palpebral fissure and malar prominence. Genetic mutations, chromosomal abnormalities, and prenatal environment can all cause anophthalmia. Anophthalmia is an extremely rare disease and is mostly rooted

Microphthalmia (Greek: , ), also referred as microphthalmos, is a developmental disorder of the eye in which one (unilateral microphthalmia) or both (bilateral microphthalmia) eyes are abnormally small and have anatomic malformations. Microphthalmia is a distinct condition from anophthalmia and nanophthalmia. Although sometimes referred to as 'simple microphthalmia', nanophthalmia is a condition in which the size of the eye is small but no anatomical alterations are present.

disorder of lens

thumb|Eye imaging showing polycoria in four different levels of light.

autosomal dominant condition with incomplete penetrance, in which nursing infants will have rhythmic upward jerking of their upper eyelid

A distichia is when cilia (eyelashes) arise from the free lid margin. This abnormality, attributed to a genetic mutation, is a common opthalmological disorder of the dog. Distichiae usually exit from the duct of the meibomian gland at the eyelid margin. They are usually multiple, and sometimes more than one arises from a duct. They can affect either the upper or lower eyelid and are usually bilateral. The lower eyelids of dogs usually have no eyelashes.

Blepharophimosis is a congenital anomaly in which the eyelids are underdeveloped such that they cannot open as far as usual and permanently cover part of the eyes. Both the vertical and horizontal palpebral fissures (eyelid openings) are shortened; the eyes also appear spaced more widely apart as a result, known as telecanthus.

Human disease

Keratoglobus (from Greek: kerato- horn, cornea; and Latin: globus round) is a degenerative non-inflammatory disorder of the eye in which structural changes within the cornea cause it to become extremely thin and change to a more globular shape than its normal gradual curve. It causes corneal thinning, primarily at the margins, resulting in a spherical, slightly enlarged eye.

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.

autosomal dominant disease characterized by abnormalities of the front part of the eye, the anterior segment

thumb|upright|Daryl Dragon (who had megalocornea) with Toni Tenille Megalocornea (MGCN, MGCN1) is an extremely rare nonprogressive condition in which the cornea has an enlarged diameter, reaching or exceeding 13 mm. It is thought to have two subforms, one with autosomal inheritance and the other X-linked (Xq21.3-q22). The X-linked form is caused by a mutation in a gene CHRDL1 which encodes Chordin-like 1 protein. Men generally constitute 90% of cases.

Human disease

genetic disorder that primarily affects the eye and almost always leads to blindness

Microspherophakia is a rare congenital autosomal recessive condition where the lens of the eye is smaller than normal and spherically shaped. This condition may be associated with a number of disorders including Peter's anomaly, Marfan syndrome, and Weill–Marchesani syndrome. The spherical shape is caused by an underdeveloped zonule of Zinn, which doesn't exert enough force on the lens to make it form the usual oval shape. It is a result of a homozygous mutation to the LTBP2 gene.

disorder of lens

congenital hereditary deformity of the eye surface