Malformations/developmental Diseases of the CNS Flashcards
very common premature pediatric neuropathology lesion
hypoxic-ischemic lesions
when does implantation of embryo occur?
7 days
when does neural tube formation occur?
22-28 days (4th week)
when does organogenesis occur?
4-8 weeks
when does migration of neuroblasts occur?
8 weeks-birth
when does myelination occur?
20 weeks on
order of formation: hindbrain neuropore, posterior neuropore or anterior neuropore?
posterior neuropore, hindbrain neuropore, anterior neuropore
lab evidence that neural tube has a problem
elevated alpha-fetal protein level in amniotic fluid (also use ultrasound to see it)
where is alpha-fetal protein produced?
liver of the fetus
Arnold-chiari malformation is a result of failure to close
anterior neuropore
things that are absent in anencephaly
absent brain and calvarium, absent descending tracts, atrophic anterior pituitary
most common neural tube defect is that of the
posterior neuropore: meningocele, myelomeningoeele
myelomeningocele characteristics
absence of vertebral arches; herniation of meninges and spinal cord through the cystic lesion; most common in lumbosacral region
Arnold-chiari main problem
flattening of the posterior fossa and a wide foramen magnum
disorders of organogenesis/ which is very common?
holoprosencephaly, olfactory aplasia (very common), agenesis of the corpus callosum, dandy-walker malformation
what is the main finding in Dandy-Walker malformation?
absence of the cerebellar vermis and a cyst in its place that connects to the 4th ventricle
early destructive lesion of the brain
schizencephaly (porencephaly)
late destructive lesions result in
cerebral palsy due to hypoxic hemorrhage complications, which usually block CSF flow in the cerebral aqueduct
damage in the white matter due to hypoxic-ischemic injury hemorrhage in the germinal matrix, choroid plexus, parenchymal, or intradural spaces
periventricular leukomalacia
