Neural Tube Defects Flashcards
List four disorders that may rise from improper closing of the anterior neural tube.
Craniorachischisis, anencephaly, encephalocele, iniencephaly.
Describe craniorachischisis.
Spinal cord and brain are open
No spinal fluid or vertebrae
Describe anencephaly.
Open brain
Lack of scull vault
Parts of brain missing
Describe encephalocele.
Vertebrae not formally formed, pushing out nervous tissue.
High pressure on brain and meninges.
Describe iniencephaly.
Fusion between scull and spinal cord. Retroflexion.
List four disorders that may rise from improper closing of the posterior neural tube.
Spina bifida occulta, closed spinal dysraphism, meningocele, myelomeningocele.
Describe spinda bifida occulta.
Some vertebrae not completely closed
Asymptomatic
Meninges and/or vertebrae defected
Describe closed spinal dysraphism.
Vertebrae missing
Spinal fluid and lipid accumulation
Describe meningocele.
Meninges inflamed, but secrete spinal fluid and cover spine.
Describe myelomeningocele.
Meninges do not cover spinal cord
Damage occurs.
Why do folic acid supplements reduce SB.
Folic acid is a precursor of purines.
What is microcephaly?
Small brain, normal patterning.
What is lissencephaly?
Absence of gyri and sulci caused by migration defects.
What is the Eph/ephrin system responsible for?
Guidance cues
List examples of guidance molecules.
Semaphorin, neuropilin and Eph/ephrin.
