microcephaly

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microcephaly

 [mi″kro-sef´ah-le]
small size of the head in relation to the rest of the body. adj., adj microcephal´ic.

mi·cro·ceph·a·ly

(mī'krō-sef'ă-lē),
Abnormal smallness of the head; applied to a cranium with a capacity less than 1350 mL. Usually associated with mental retardation.
[micro- + G. kephalē, head]

microcephaly

/mi·cro·ceph·a·ly/ abnormal smallness of the head.microcephal´ic

microcephaly

(mī′krō-sĕf′ə-lē)
n. pl. microcepha·lies
Abnormal smallness of the head.

mi′cro·ce·phal′ic (-sə-făl′ĭk) adj. & n.
mi′cro·ceph′a·lous (-sĕf′ə-ləs) adj.

microcephaly

[mī′krōsef′əlē]
Etymology: Gk, mikros + kephale, head
a congenital anomaly characterized by abnormal smallness of the head in relation to the rest of the body and by underdevelopment of the brain, resulting in some degree of mental retardation. The head is more than two standard deviations below the average circumference size for age, sex, race, and period of gestation. It has a narrow, receding forehead; a flattened occiput; and a pointed vertex. The facial features are generally normal. The condition may be caused by an autosomal-recessive disorder, a chromosomal abnormality, a toxic stimulus such as irradiation or chemical agents, maternal infection during prenatal development, or any trauma, especially during the third trimester of pregnancy or early infancy. There is no treatment, and nursing care is primarily supportive and educational, helping parents learn to care for a brain-damaged child. Also called microcephalia, microcephalism. Compare macrocephaly. microcephalic, microcephalous, adj., microcephalic, microcephalus, n.

microcephaly

An abnormally small head, which is usually associated with neurodevelopmental delay and mental retardation. A standard definition is any brain or head which is ≥ 3 standard deviations below the mean for a person’s age, sex, height, weight and race.

Conditions associated with microcephaly
Cockayne, Miller-Dieker, Smith-Lemli-Opitz, Rothmund-Thomson, and Wolf-Hirschhorn syndromes; chromosomal defects (cat-cry or 5p- and trisomy 13 syndromes), in utero infection (CMV), rubella, toxoplasmosis, toxic exposure (foetal alcohol and foetal hydantoin syndromes), radiation (the only confirmed congenital defect specifically linked to atomic bomb blasts (i.e., in Hiroshima and Nagasaki)), or trauma.

Genes linked to microcephaly
ASPM, CDK5RAP2, CENPJ, MCPH1, MCPH2, MCPH4.

microcephaly

Neonatology An abnormally small head, often associated with developmental delay and mental retardation; any brain or head that is ≥ 3 standard deviations below the mean for a person's age, sex, height, weight, race. Cf Macrocephaly.

mi·cro·ceph·a·ly

, microcephalia (mī'krō-sef'ă-lē, -sĕ-fālē-ă)
Abnormal smallness of the head; applied to a cranium with a capacity less than 1350 mL. Usually associated with mental retardation.
Synonym(s): nanocephaly.
[micro- + G. kephalē, head]

microcephaly

Abnormal smallness of the skull. Microcephaly often reflects poor brain development and is usually associated with MENTAL RETARDATION.

Microcephaly

An abnormally small head.

Paine,

R.S.,
Paine retinaculatome
Paine syndrome - males only; onset at birth; physical and mental retardation; seizures. Synonym(s): microcephaly
Paine-Efron syndrome - pain in the back and thigh followed by slowly progressive ataxia. Synonym(s): ataxia-telangiectasia variant

microcephaly (mīˈ·krō·seˑ·f·lē),

n a congenital disorder characterized by an abnormally small head relative to the rest of the body and an underdeveloped brain; may result in mental retardation; caused by a chromosomal anomaly or exposure to trauma or toxic stimulus during prenatal development.

mi·cro·ceph·a·ly

, microcephalia (mī'krō-sef'ă-lē, -sĕ-fālē-ă)
Abnormal smallness of the head; often associated with mental retardation.
[micro- + G. kephalē, head]

microcephaly

small size of the head in relation to the rest of the body.