neural tube defects
- a group of congenital abnormalities caused by failure of the neural tube to form normally. In spina bifida the bony arches of the spine, which protect the spinal cord and its coverings (the meninges), fail to close. More severe defects of fusion of these bones will result in increasingly serious neurological conditions. A meningocele is the protrusion of the meninges through the gap in the spine, the skin covering being vestigial. There is a constant risk of damage to the meninges, with resulting infection. Urgent surgical treatment to protect the meninges is therefore required. In a meningomyelocele (myelomeningocele, myelocele) the spinal cord and the nerve roots are exposed, often adhering to the fine membrane that overlies them. There is a constant risk of infection and this condition is accompanied by paralysis and numbness of the legs and urinary incontinence. hydrocephalus and an Arnold-Chiari malformation are usually present. A failure of fusion at the cranial end of the neural tube (cranium bifidum) gives rise to comparable disorders. The bone defect is most often in the occipital region of the skull but it may occur in the frontal or basal regions. A protrusion of the meninges alone is known as a cranial meningocele. The terms meningoencephalocele, encephalocele, and cephalocele are used for the protrusion of brain tissue through the skull defect. This is accompanied by severe mental and physical disorders.
Medical dictionary. 2011.
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neural tube defects — a group of congenital abnormalities caused by failure of the neural tube to form normally. In spina bifida the bony arches of the spine, which protect the spinal cord and its coverings (the meninges), fail to close. More severe defects of fusion… … The new mediacal dictionary
Дефекты Развития Нервной Трубки (Neural Tube Defects) — ряд врожденных пороков, связанных с нарушением нормального развития нервной трубки. При расщелине позвоночника имеет место неполное закрытие костных дуг позвоночника, защищающих спинной мозг и его оболочки. При более тяжелых пороках развития… … Медицинские термины
Neural tube defect — Classification and external resources ICD 10 Q00, Q01, Q05 … Wikipedia
Neural tube — Transverse section of half of a chick embryo of forty five hours incubation. The dorsal (back) surface of the embryo is towards the top of this page, while the ventral (front) surface is towards the bottom. (Neural tube is in green.) … Wikipedia
neural tube — n the hollow longitudinal dorsal tube that is formed by infolding and subsequent fusion of the opposite ectodermal folds in the vertebrate embryo and gives rise to the brain and spinal cord * * * the embryological structure from which the brain… … Medical dictionary
neural tube defect — Pathol. any of a group of congenital abnormalities involving the brain and spinal cord, including spina bifida and meningocele, caused by failure of the neural tube to close properly during embryonic development. [1885 90] * * * Congenital defect … Universalium
Neural tube defect (NTD) — A birth defect caused by abnormal development of the neural tube. (The neural tube is the structure present during embryonic life which gives rise to the central nervous system to the brain and the spinal cord.) The best known neural tube defects … Medical dictionary
neural tube — the embryological structure from which the brain and spinal cord develop. It is a hollow tube of ectodermal tissue formed when two edges of a groove in a plate of primitive neural tissue (neural plate) come together and fuse. Failure of normal… … The new mediacal dictionary
neural tube defect — n any of various congenital defects (as anencephaly and spina bifida) caused by incomplete closure of the neural tube during the early stages of embryonic development * * * a developmental anomaly consisting of failure of closure of the neural… … Medical dictionary
Defect, neural tube — A birth defect caused by abnormal development of the neural tube. (The neural tube is the structure present during embryonic life which gives rise to the central nervous system to the brain and the spinal cord.) The best known neural tube defects … Medical dictionary