Congenital Abnormality
anencephaly
an·en·ceph·a·ly [ an-en-sef-uh-lee ]
Subclass of:
Abnormality, Severe Teratoid;
Neural Tube Defects
Etymology:
Greek a (an-) = not + enkephalon = brain
Definitions related to anencephaly:
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A birth defect in which an infant is born without most of the brain or without the skull bones covering the brain.Harvard Dictionary of Health TermsHarvard Medical Publishing, 2011
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A malformation of the nervous system caused by failure of the anterior neuropore to close. Infants are born with intact spinal cords, cerebellums, and brainstems, but lack formation of neural structures above this level. The skull is only partially formed but the eyes are usually normal. This condition may be associated with folate deficiency. Affected infants are only capable of primitive (brain stem) reflexes and usually do not survive for more than two weeks. (From Menkes, Textbook of Child Neurology, 5th ed, p247)NLM Medical Subject HeadingsU.S. National Library of Medicine, 2021
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A rare neural tube defect during pregnancy, resulting in the absence of a large portion of the brain and skull in the fetus.NCI ThesaurusU.S. National Cancer Institute, 2021
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Absence of the cranial region of the head, with the brain absent or reduced. (Makris S, Solomon HM, Clark R, Shiota K, Barbellion S, Buschmann J, Ema M, Fujiwara M, Grote K, Hazelden KP, Hew KW, Horimoto M, Ooshima Y, Parkinson M, Wise LD. Terminology of developmental abnormalities in common laboratory mammals (Version 2). Part B. Birth Defects Res B Dev Reprod Toxicol. 2009 Aug;86(4):227-327.)CDISC TerminologyClinical Data Interchange Standards Consortium (CDISC), 2021
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Anencephaly is a developmental anomaly characterized by a fetus that has no calvarium, with a lack of most or all of the fetus' brain tissue. Anencephaly belongs to a collective group known as neural tube defects (NTD) and is a result of the neural tube failing to close in its rostral end during fetal development.Human Phenotype Ontology (HPO)The Human Phenotype Ontology Project, 2021
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(anencephalus) Congenital malformation of the nervous system caused by failure of the anterior neuropore to close; infants are born with intact spinal cords, cerebellums, and brainstems, but lack formation of neural structures above this level; the skull is only partially formed but the eyes are usually normal; affected infants are only capable of primitive reflexes and usually do not survive for more than two weeks; complete absence of the brain is rare.CRISP ThesaurusNational Institutes of Health, 2006
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Anencephaly is absence of the cerebral hemispheres. The absent brain is sometimes replaced by malformed cystic neural tissue, which may be exposed or covered with skin. Parts of the brain stem and spinal cord may be missing or malformed. Infants are stillborn or die within days or weeks.Merck & Co., Inc., 2020
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Anencephaly is a serious developmental defect of the central nervous system in which the brain and cranial vault are grossly malformed. The cerebrum and cerebellum are reduced or absent, but the hindbrain is present.WebMD, 2019
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Anencephaly is a type of neural tube defect characterized by abnormal development of the brain and the bones of the skull. The neural tube is a narrow channel that normally folds and closes between the 3rd and 4th weeks of pregnancy, forming the brain and spinal cord of the embryo. Anencephaly occurs when the 'cephalic' or head end of...National Center for Advancing Translational Sciences
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