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an infant with anencephaly.


An infant with anencephaly.


A fetus lacking all or most of the brain.
[G. an, without, + enkephalos, brain]


(an?en-sef'a-le) [Gr. an-, not, + enkephalos, the brain]
Congenital absence of the brain and cranial vault, with the cerebral hemispheres missing or reduced to small masses. This condition is incompatible with life. In the U.S., it is present in about 11 births out of 100,000. This defect results from the lack of closure of the anterior neural tube. Like other neural tube defects, the risk for anencephaly can be reduced with folic acid supplementation (800 mg daily) taken by women before and during pregnancy. See: neural tube defect
anencephalicanencephalus (an?en-se'fal-ik) (an?en-sef'a-lus), adjective
References in periodicals archive ?
Cases (infants or fetuses) had a diagnosis of anencephalus [International Classification of Diseases, 9th Revision Clinical Modification (ICD-9-CM) (Medicode, Inc.
Central nervous system defects (including anencephalus and similar anomalies, spina bifida, and other congenital anomalies of the central nervous system and eye) were the second largest group, occurring in 1991 (14.
Six major CNS defects were reported: one case of spina bifida, two anencephalus cases, two hydrocephalus cases, and one case of multiple congenital anomalies.