Low-set ears are a clinical feature in which the ears are positioned lower on the head than usual. They are present in many congenital conditions. Low-set ears are defined as
outer ears positioned two or more
standard deviations lower than the population average.
Clinically, if the point at which the helix of the
outer ear
The outer ear, external ear, or auris externa is the external part of the ear, which consists of the auricle (also pinna) and the ear canal. It gathers sound energy and focuses it on the eardrum ( tympanic membrane).
Structure
Auricle
T ...
meets the cranium is at or below the line connecting the inner
canthi of eyes(bicanthal plane), the ears are considered low set.
Low-set ears can be associated with conditions such as:
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Down syndrome
Down syndrome or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is usually associated with child development, physical growth delays, mild to moderate ...
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Turner syndrome
Turner syndrome (TS), also known as 45,X, or 45,X0, is a genetic condition in which a female is partially or completely missing an X chromosome. Signs and symptoms vary among those affected. Often, a short and webbed neck, low-set ears, low h ...
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Noonan syndrome
Noonan syndrome (NS) is a genetic disorder that may present with mildly unusual facial features, short height, congenital heart disease, bleeding problems, and skeletal malformations. Facial features include widely spaced eyes, light-colored ...
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Patau syndrome
Patau syndrome is a syndrome caused by a chromosomal abnormality, in which some or all of the cells of the body contain extra genetic material from chromosome 13. The extra genetic material disrupts normal development, causing multiple and compl ...
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DiGeorge syndrome
DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent ...
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Cri du chat syndrome
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Edwards syndrome
Edwards syndrome, also known as trisomy 18, is a genetic disorder caused by the presence of a third copy of all or part of chromosome 18. Many parts of the body are affected. Babies are often born small and have heart defects. Other features in ...
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Fragile X syndrome
Fragile X syndrome (FXS) is a genetic disorder characterized by mild-to-moderate intellectual disability. The average IQ in males with FXS is under 55, while about two thirds of affected females are intellectually disabled. Physical features may ...
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Okamoto syndrome
It is usually bilateral, but it can be unilateral in
Goldenhar syndrome.
See also
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LEOPARD syndrome
References
External links
Diseases of the ear and mastoid process
Congenital disorders of ears
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