Neuro 3 Flashcards
what does the term lissencephaly mean?
absence of normal gyri and sulci of the cerebrum, aka it’s a smooth brain
what are the names for a small brain cavity and a large brain cavity. what is a general cuase for these?
small=porencephaly
large=hydranencephaly
viral damage (like bluetongue, BVDV, etc)
what two virus types can cause cerebellar hypoplasia?
parvoviruses like canine parvo and feline panluekopenia
pestiviruses like BVDV and classical swine fever
both types target rapidly dividing cells (so it hits the cerebellum)
the most common CNS congenital anomaly is
hydrocephalus
what is hydrocephalus?
abnormal accumulation of CSF within the cranium
what is the cause of congenital hydrocephalus? which animals are predisposed to this?
secondary to in utero viral infection
- brachy breeds like chihuahua, bulldog, pug, yorkie, toy poodle, etc
what are the three types of hydrocephalus?
- congenital
- acquired
- hydrocephalus ex vacuo
what causes acquired hydrocephalus?
- some sort of obstruction (inflammatory blockage, infection, compression from a mass or abscess, etc)
what is hydrocephalus ex vacuo and what causes it
-aka compensatory hydroephalus, where the CSF replaces lost neural tissue
not related to CSF obstruction, but is actually an aging change or can also happen after radiation exposure
describe where fluid accumulation would be in each scenario regarding hydrocephalus if the bloackage were located:
- interventricular foramen between lateral and third ventricle
- blockage of mesencephalic aqueduct
- blockage of resorption of CSF
- unilateral dilation of affected lateral ventricle
- bilateral dilation of lateral ventricles, 3rd ventricle, and cranial part of mesencephalic aqueduct
- everything dilated!
what are some gross findings of hydrocephalus?
- if congenital, an enlarged domed skull with prominent fontanelles
- atrophy and loss of interventricular septum pellucidum
which breed of dog can have hydrocephalus but show no clinical signs?
toy breeds
what is occipital dysplasia?
common incidental finding in toy breeds where there is an underdeveloped occipital bone of the skul, resulting in a keyhole shaped foramen magnum. it does not cause clinical signs
what is this
occiptal dysplasia
listeriosis is caused by _________, and has 3 disease presentations which are:
listeria monocytogenes, gram +, small ruminants, zoonotic
- meningoencephalitis (adult animals)
- abortion/stillbirth (young animals)
- septicemia (young animals)
what is the pathogenesis of listeriosis in regards to meningoencephalitis?
- consumption of improerly prepared silage that contains high numbers of bacteria, trauma to the oral mucosa allows bacterial invasion, migration to trigeminal ganglia and then to the brainstem via retrograde axonal transport, leading to inflammatory damage in the brain
what are some clinical signs of listeriosis and histo lesions?
C/S: circling, twisted neck, dullness, padding
histo: microabscesses w neutrophils