Heterochromia can be present at birth (congenital) or acquired. The incidence of congenital heterochromia iridis is approximately six out of a 1,000, although in most of these cases, it is hardly noticeable and unassociated with any other abnormality.
HETEROCHROMIA IRIDIS How rare is heterochromia iridis? Heterochromia can be present at birth (congenital) or acquired. The incidence of congenital heterochromia iridis is approximately six out of a 1,000, although in most of these cases, it is hardly noticeable and unassociated with any other abnormality. What causes heterochromia iridis Heterochromia is classified primarily by its time of onset as either genetic (congenital, present at or shortly after birth) or acquired. Most cases of heterochromia are hereditary, and these may be associated with a congenital syndrome. Other cases are acquired and caused by a disease or due to an injury. Sometimes one eye may change color following certain diseases or injuries. Heterochromia present at or shortly after birth is usually hereditary or due to intrauterine disease or injury. Congenital heterochromia may be familial and is inherited as an autosomal dominant trait. Inherited eye color is determined by multiple genes. Environmental or acquired factors can alter these inherited traits. An infant with heterochromia should be examined by both a pediatrician and an ophthalmologist for other possible problems. If another disorder is suspected, diagnostic tests, such as blood tests or chromosome studies, may be done to confirm the diagnosis. Most cases of heterochromia at birth are genetic and unassociated with any other ocular or systemic abnormality. This is simply called congenital heterochromia iridis. The lighter eye usually shows some loss of iris and therefore is
Transcript
HETEROCHROMIA IRIDIS
How rare is heterochromia iridis?Heterochromia can be present at birth (congenital) or acquired. The incidence
of congenital heterochromia iridis is approximately six out of a 1,000, although in
most of these cases, it is hardly noticeable and unassociated with any other
abnormality.
What causes heterochromia iridis
Heterochromia is classified primarily by its time of onset as either genetic
(congenital, present at or shortly after birth) or acquired. Most cases of
heterochromia are hereditary, and these may be associated with a congenital
syndrome. Other cases are acquired and caused by a disease or due to an injury.
Sometimes one eye may change color following certain diseases or injuries.
Heterochromia present at or shortly after birth is usually hereditary or due to
intrauterine disease or injury. Congenital heterochromia may be familial and is
inherited as an autosomal dominant trait. Inherited eye color is determined by
multiple genes. Environmental or acquired factors can alter these inherited traits. An
infant with heterochromia should be examined by both a pediatrician and an
ophthalmologist for other possible problems. If another disorder is suspected,
diagnostic tests, such as blood tests or chromosome studies, may be done to
confirm the diagnosis.
Most cases of heterochromia at birth are genetic and unassociated with any
other ocular or systemic abnormality. This is simply called congenital heterochromia
iridis. The lighter eye usually shows some loss of iris and therefore is regarded as
the affected eye. The lighter iris may be differently colored throughout or only in part.
Congenital syndromes which may be characterized by heterochromia iridis
include:
Waardenburg syndrome, a genetic condition that can cause hearing loss and
changes in coloring of the hair, skin, and eyes.
"Piebaldism" is similar to Waardenburg syndrome but is unassociated with
deafness. People with this condition have patches of depigmented skin on their
head and trunk, as well as on their eyebrows, eyelids, eyelashes, and hair.
Affected people sometimes have heterochromia iridis.
Congenital "Horner's syndrome" is not a genetic syndrome, but a group of
findings due to birth injury or intrauterine brain injury involving the sympathetic
nervous system innervation to one eye. On the affected side, the pupil is small,
the lid is drooping, and the iris is lighter. It is not associated with hearing loss or
additional pigmentation anomalies.
Sturge-Weber syndrome, a syndrome characterized by a port-wine stain in the
distribution of the trigeminal nerve on the face and tumors known as angiomas
of the brain and choroid.
Neurofibromatosis type 1, also known as von Recklinghausen disease, is a
disorder in which there are tumors of nerve cells together with disorders of
melanin, causing abnormalities of skin (and eye) pigmentation. Lisch nodules
are usually present in the iris. These are clear yellow to brown dome-shaped
elevations on the iris and, although they are usually present in both eyes, may
be more apparent in one eye.
Tuberous sclerosis, also known as Bourneville disease, causes nonmalignant
tumors in various organs including the eyes.
Hirschsprung disease, a bowel disorder, may be associated with iris
heterochromia due to reduction is iris pigmentation.
Incontinentia pigmenti, also known as Bloch–Sulzberger syndrome, affects the
skin, hair, teeth, nails, and central nervous system. In this condition, the iris
may be darker in the affected eye.
Parry-Romberg syndrome, or progressive hemifacial atrophy, is a condition that
causes the breakdown of the skin and soft tissues of half of the face.
Acquired conditions or diseases that may present with heterochromia iridis
include:
The inflammation of iritis or anterior uveitis of any cause,
includingtuberculosis, sarcoidosis, and herpes simplex, may cause loss of iris
pigment in the affected eye.
Fuchs' heterochromic cyclitis is a condition characterized by a low-grade,
asymptomatic uveitis in which the iris in the affected eye becomes hypochromic
and has a washed-out, somewhat moth-eaten appearance.
Posner-Schlossman Syndrome, or glaucomatocyclitic crisis, may cause a
lighter iris with repeated attacks.
Pigment dispersion syndrome is a condition characterized by loss of
pigmentation from the posterior iris surface. This pigment is dispersed
throughout the interior of the eye and deposited on various intraocular
structures, including the anterior surface of the iris, causing it to darken. This
condition also causes pigmentary glaucoma.
Trauma, either blunt or penetrating, may cause unilateral lightening of the iris
through atrophy of the iris.
Prostaglandin analogue eyedrops (Xalatan, Lumigan, Travatan, and others),
frequently used for the treatment of glaucoma, may cause darkening of the iris,
especially in people with light-colored irises. This occurs from the stimulation of
melanin production. This type of medication is also sometimes used for
cosmetic purposes (Latisse) to darken and thicken the eyelashes.
Retained iron-containing intraocular foreign body may cause siderosis (iron
deposition within the eye) resulting in a darker iris.
Blood in the anterior chamber (hyphema) of long duration from trauma can lead
to iron deposition in the iris from the breakdown of blood products.
Ocular melanosis, or nevus of Ota, is a condition characterized by increased
pigmentation of the eye and surrounding tissue.
Iris ectropion syndrome is a condition in which the back of the iris, which is
always dark and full of melanin pigment, turns onto the front of the iris through
the pupillary space.
Benign tumors of the iris, iris cysts, and iris abscesses can cause darkening or
lightening of the iris.
Malignant melanoma of the iris or metastatic tumors of the iris.
Neovascular changes of the iris (rubeosis iridis) resulting from diabetes
mellitus or following central retinal vein occlusion.
Acquired Horner syndrome from neuroblastoma or injury/disease affecting the
sympathetic nervous system in the neck.
Chediak-Higashi syndrome is a rare genetic disorder that may manifest in
childhood with recurrent infections, peripheral neuropathy, and color changes in
the skin and eye.
Clouding of the cornea or color changes in the cornea from a multitude of
conditions may cause the iris to falsely appear to be different in color.
Conditions such as corneal scars, the very common condition of arcus senilis,
or the rare condition of Wilson disease can give the appearance of iris color
differences.
Reviewed by Melissa Conrad Stöppler, MD on 5/21/2013http://www.medicinenet.com/heterochromia_iridis/page2.htm
Celebrities with heterochromia have a fascinating condition: Their eyes are actually two different colors. In some cases, this anomaly is extremely noticeable, in other cases it is a bit more subtle. Either way, everyone listed here has the relatively rare and really cool condition called "heterochromia iridis," meaning the irises of their eyes are different colors. Prepare to be amazed, because some of these famous people with different colored eyes are without question among the most beautiful women in Hollywood and some of the greatest film actors and actresses of all time, too.
Is having heterochromia a blessing, or a curse? Looking at the celebrities with different-colored eyes here, it's easy to believe it's a blessing.
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