Term
Occult Dysraphic States AKA myelodysplasia |
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Definition
Error of secondary neurulation. Group of malformations due to abnormal development of caudal level of spinal cord. Covered with skin (occult=hidden). delay in sphincter control, foot anomalies |
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Term
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Definition
Absence of calvaria. Rudimentary mass of forebrain and midbrain. increased alpha fetoprotein levels can diagnose this |
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Definition
bifid cranium with herniation of brain and meningeal coverings |
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Definition
small skull defect with with herniated meningial sac filled with CSF. No brain herniation |
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Definition
opening btwn skull bones. usually asymptomatic |
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Term
Myeloschisis (spina bifida aperta) |
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Definition
neural plate open dorsally, no neural tube formation in this area. no function below lesion. Most severe spina bifida |
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Definition
cystic swelling covered by skin or membrane. herniation of spinal cord and meninges. No function below lesion. Most common of spina bifida cystica (90%) |
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Definition
vertebral defect. herniated meningial sac filled with CSF. Least common of SB cystica (10%) |
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Term
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Definition
in 10% of population. Vertebral defect limited to 1-2 vertebrae. usually asymptomatic. may be assoc with skin dimple, fatty cyst, hair tuft, or diastematomyelia (bone spur in spinal canal that can tether spinal cord and keep it from ascending) |
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Term
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Definition
Failure of bilateralization of the forebrain |
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Term
During what weeks does primary neurulation occur |
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Definition
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Term
During what weeks does secondary neurulation occur |
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Definition
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Term
Five regions of the developing brain |
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Definition
(from cranial to caudal)- Telencephalon, Diencephalon, Mesencephalon, Metencephalon, myelencephalon |
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Term
What brain region forms the cerebellum |
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Definition
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Term
What brain region forms the cerebral hemispheres |
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Definition
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Term
what brain region forms the midbrain |
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Definition
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Term
what brain region forms the pons |
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Definition
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Term
what brain region forms the medulla |
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Definition
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Definition
over-proliferation of neurons, causes enlarged head |
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Definition
under-proliferation of neurons. small head |
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Definition
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Term
communicating hydrocephalus |
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Definition
CSF can get into subarachnoid space but can't get to the subarachnoid granulations |
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Term
Non-communicating hydrocephalus |
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Definition
CSF can't get into subarachnoid space. Block is usually at cerebral aqueduct |
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Term
Arnold-Chiari malformation |
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Definition
caudal displacement and herniation through the foramen magnum of ventrally located cerebellar structures. The direction of some of the cervical roots may be rotated 180 degrees |
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Term
Precursors for primary sensory neurons |
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Definition
mostly neural crest cells. some in head by ectodermal placodes |
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Term
Precursor for somatic motor neurons |
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Definition
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Term
Precursor for preganglionic autonomic neurons |
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Definition
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Term
precursor for postganglionic autonomic neurons |
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Definition
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