cranial nerves Flashcards
what is the monroe- kelly hypothesis?
intercranial volume= vol (CNS)+ vol (blood)+ vol (lesion)
What is the ICP taken in LLD?
< 200 mmH20
<15 mmHg
what symptoms will you experience with uncle herniation?
ipsilateral CN III palsy causing ipsilateral pupillary dilation and paresis of extra occular muscles except SO4 and LR6
* eyes drift down and out
what is the only CN that coms off the posterior brainstem?
IV- trochlear
hyperosmia
smell overpowering things- happens as an aura with migranes, or seizures of the temporal lobe
hypoosmia
loss of small as you age
degenerative
anosmia
loss of all smell associated with brain atrophy from nasal, paranasal disease, infection or trauma
when you shine a light on someones eye what are you testing?
brainstem, optic nerve, CN II and II and pupillary reflex
what is a kernohan notch and when is it present?
when the contralateral (to the uncle herniation) cerebral peduncle is driven into the tentorium cerebelli
what does kernohan notch cause?
hemiparesis on the opposite side of the notch
what is the false localizing sign?
ipsilateral to the hemisperic mass
what is a cingulate herniation?
when one hemisphere is forced under the falx cerebri, usually the cingulate lobe is the first to be displaced
the anterior cerebral a is also displaced under the falx
what are the symptoms of a cingulate herniation?
the anterior cerebral a is also displaced under the falx causing contralateral LE weakness and sometimes confusion and drowsiness
what is a central herniation?
herniation of both hemispheres transtentorally
what are the symptoms of central herniation?
bilateral pupil dilation
comma
flaccidity
displacement of vessels can wretch vessels causing a linear hemmorrage called a duret hemmorages
what is a cerebellar tonsillar herniation?
cerebellar tonsils get compressed, which compress the medually centers
can result in sudden death
stop breathing no CV or Resp control
in kids 80% of brain tumors are where?
below the tentorium cerebelli
