Just like snowflakes, no two pair of eyes are alike. Sometimes, the two irises are a completely different color! Heterochromia is an uncommon mutation where one the eyes or part of one eye is a different color. This is caused by the lack of melanin (a type of pigment) in the eyes. There are many causes of this mutation.
There are two types of Heterochromia: Heterochromia Iridum and Heterochromia Iridus. Heterochromia Iridum is the complete discoloration of the iris from the other iris. An example of this would be a person who has one blue eye and one green eye. Heterochromia Iridus is when only parts of the iris are a different color from the rest of the iris. Sectoral Heterochromia and Central Heterochromia are both types of Heterochromia Iridus. Sectoral Heterochromia is when parts or sections of the iris is a different color than the rest of the iris. Central Heterochromia is when the center of the iris near the pupil is a different color than the surrounding iris. This type of Heterochromia is more common than others. Hazel eyes are often referred to as Central Heterochromia because of the discoloration around the pupil.
Heterochromia is caused by the lack or complete absence of the pigment melanin in the early development of the body. The deficiency, or complete absence of melanin also causes albinism and is found in skin color and hair (Haldeman-Englert). In most cases, Heterochromia is usually passed down genetically, but it could also be contracted by a mere punch in the eye. There are many syndromes and infections that are linked to Heterochromia. Elderly people that have cataracts or glaucoma have a slight chance of getting Heterochromia. The discoloration or pigment levels in the eyes affected have no foreseeable we...
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...ll,” (New International Version, Ps. 139. 140).
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Bures-Jelstrup A, Adan A, Casaroli-Marano R. [Acute posterior multifocal placoid pigment epitheliopathy. Study of 16 cases]. Archivos de la Sociedad Espanola de Oftalmologia. 2007;82(5):291-7. Epub 2007/05/23. Epiteliopatia pigmentaria placoide posterior multifocal aguda. Estudio de 16 casos.
Loss of vision in one or both eyes
In the Radiolab episode “Colors,” Adam Cole hosts Jay Neitz, a neurologist and color vision researcher at the University of Washington, to discuss colorblindness in primates and humans. Neitz hypothesizes that the test they used to cure colorblindness in squirrel monkeys could also cure the same disorder in humans. Colorblindness is a genetic disorder that causes the cones in the eye to perceive colors differently. In the back of the eye lies the retina that holds three photoreceptor cells called cones. Each cone is sensitive to either red, green, or blue and when functional, allows the brain to process the different wavelengths of color. Humans and some primates have two genes on the X Chromosome that encodes visual pigments, one holds green
The novel The Bluest Eye written by Toni Morrison is subjected on a young girl, Pecola Breedlove and her experiences growing up in a poor black family. The life depicted is one of poverty, ridicule, and dissatisfaction of self. Pecola feels ugly because of her social status as a poor young black girl and longs to have blue eyes, the pinnacle of beauty and worth. Throughout the book, Morrison touches on controversial subjects, such as the depicting of Pecola's father raping her, Mrs. Breedlove's sexual feelings toward her husband, and Pecola's menstruation. The book's content is controversial on many levels and it has bred conflict among its readers.
Albinism is a genetic condition present at birth, characterized by a small amount of melanin pigment in the skin, hair and eye. Albinism is an occasional inborn sickness related with vision difficult, which affect one in seventeen thousand persons. It is not a contagious disease and cannot be spread over contact. Albinism affects individuals from all races. Most folks with albinism have parents with a normal color of skin. Some may not even recognize that they are Albino until later on in their life. This paper will be based on the study of albinism, causes, types, the genetic transmission and some possible medical problem.
Albinism is a genetic disorder that is caused by the lack of pigments. Sometimes it only affects the eye which is called ocular albinism. You can receive albinism from your genetics. You can be an albino in your eyes, skin or hair. It affects people of all races and all around the world. Studies show one in 20,000 people worldwide have some form of albinism. Certain forms of albinism are more common in some populations. Most common form of albinism is OCAZ and is found in one in 36, 0000 Caucasians in the United States. There are four types of albinism; type 1 is characterized by white hair, very pale skin, and light colored eyes. Type 2 is less severe their skin is usually a creamy white color and their hair could be a light yellow, blonde or light brown. Type 3 has a form of albinism called “rufous oculocutaneous albinism” this usually affects dark-skinned people. They have reddish-brown skin, ginger or red hair and hazel or brown eyes. Type 3 has milder vision problems. Type 4 has the same symptoms similar to type 2. Types 1 and 2 are the most common forms; types 3 and 4 are not as common.
Human pigmentation is influenced by hemoglobins within blood vessels in the skin, carotene and melanins. Melanin, the basis of pigmentation, can be found in the forms of eumelanin and phaeomelanin. Eumelanin is the brown-black pigment located in the skin, hair, and eyes. Phaeomelanin is a yellow to reddish-brown pigment found in small quantities within the skin, eyes, and red hair. Because of these two pigments, to a greater or lesser degree, we have the variation in human pigmentation that is seen today.
“Colorism” is a conventional motif in The Skin I’m In by Sharon G. Flake. Flake writes about a young black thirteen year old girl named, Maleeka Madison. Throughout the story Maleeka has an internal battle with herself about gaining self-confidence and to be more secure about herself.
Many signs include a "white pupil," also known as leukocoria. Retinoblastoma can occur in either one or two eyes (Paul T. Finger, Pg. 1). This abnormal white pupillary reflex is sometimes referred to as a cat's eye reflex. Another sign of retinoblastoma is a crossed eye (Ambramson, Ch3). Leukocoria doesn't always end up as being retinoblastoma, it can even result in: congenital cataract, Toxocara canis, Coat's disease, and persistent hypertrophic primary vitreous (PHPV) (Finger, Pg.2). Retinoblastoma occurs when there's a mutation or deletion of the q14 band of chromosome 13 (Finger, Pg. 1). Symptoms can be painful if not treated quickly. Some include a red, painful eye, swelling of the surrounding eye, poor vision, dilated pupil, even extra fingers or toes, and retardation (Ambramson, Ch3).
There are several types of amblyopia. Researchers must be aware of the various types of amblyopia because the effects for each are not always consistent. Strabismic amblyopia is caused when the two eyes are out of alignment due to weak musculature. Anisometropic amblyopia is a result of a large difference in refractive power of an individual's eyes. Another form of amblyopia results when visual information does not reach the retina. This is called stimulus deprivation amblyopia. Meridional amblyopia is a result of the diffused images caused by astigmatism. Researchers often discover that there are differences between groups of amblyopes based on type. For example, Levi and his colleagues (1994) discovered differences in vernier acuity between anisomet...
In Toni Morrison's The Bluest Eye, the character Claudia struggles with a beauty standard that harms her sense of self-esteem. Claudia tries to make sense of why the beauty standard does not include black girls. The beauty standard determines that blonde-haired blue-eyed white girls are the image of beauty and therefore they are worthy of not only attention, but are considered valuable to American culture of the 1940s. Thus, learning she has no value or beauty as a black girl, Claudia destroys her white doll in an attempt to understand why white girls are beautiful and subsequently worthy, socially superior members of society. In destroying the doll, Claudia attempts to destroy the beauty standard that works to make her feel socially inferior and ugly because of her skin color. Consequently, Claudia's destruction of the doll works to show how the beauty standard was created to keep black females from feeling valuable by producing a sense of self-hate in black females. The racial loathing created within black women keeps them as passive objects and, ultimately, leads black women, specifically Pecola, to destroy themselves because they cannot attain the blue eyes of the white beauty standard.
Regarding to the ocular examination, the patient's visual acuity without optical correction (spectacle) was good 20/20 in both eyes. IOP measurements was 18 mmHg on the right eye and 16 mmHg in the left eye. The pupil was equal, round and reactive to light with no afferent pupillary defect in both eyes. In extarocular movement test, there was limited downward gaze with
... Blue color blindness is extremely rare, so rare that only five percent of color blind people suffer from it. The chance of having blue color blindness is equal in both men and women, as the gene is found on a different chromosome, chromosome seven. Red green colorblindness is usually found only in men. The gene that leads to Red green color blindness is found in the X chromosome. Color blindness isn’t constant in all countries and is more common in males than in females. For ethnicity it is more common in Caucasians/white people. Red- green color blindness affects ten percent of males in the United States, while only five percent of women are affected. 99% of all people with color blindness have Red-green color blindness. Overall color blindness effects a person’s life, but usually not severely, and it is more common in men than in women.
The images formed on the two retinas are so unlike that they cannot be blended in the brain. Thus, a double image is perceived. The condition is known as diplopia, or double vision. Prismatic lenses are prescribed to correct this defect.Imperfections in the cones of the retina, resulting from heredity or disease, cause defective color vision. This is known as color blindness, or Daltonism. In total color blindness, everything appears in shades of gray.