Hydrocephalus Flashcards
patient presents with 3wk history of worsening headache , trouble walking and visual impairment … may be sign of?
Neoplastic: metastasis, meningioma, prim glial tumour
Infectious abscess
Vascular: intracerebral haemorrhage
Hydrocephalus secondary to neoplasm?
approach for patient?
ABCDE
what lab tests may you want to take
FBC, U+E, clotting screen
investigations?
urgent CT head,
if there is a lesion in the cerebellum, what features might you find on examination or history
DANISH Disdiadochikinesis Ataxia nystagmus intentional tremor slurred speech Hypotonia
if there is a lesion in the cerebellar vermis what might this show on examination
truncal ataxia and a broad based gait
a cerebellar hemispheric lesion would cause what on examination
loss of co-ordination ipsilaterally, intentional tremor, past pointing, disdiadochokinesis and nystagmus.
What is CSF
clear, proteinaceous fluid that bathes the CNS.
functions of CSF (3)
protects brain from BD by buffering the brain,
excretes waste products( harmful drugs or metabolites and transports hormones
How much CSF is circulating at any given moment
150ml - 17% is in the ventricles
remaining is in cisterns and subarachnoid space
where is CSF formed
choroid plexuses (specialised vascular tissue)
where are the choroid plexuses located
lateral ventricles, 3rd and 4th
where does CSF flow from the lateral ventricles
through the right and left foramen of Munro (interventricular foramen) into the third ventricle.
Next, it flows through the aqueduct of Sylvius into the fourth ventricle.
the 4th ventricle is anterior to what
cerebellum
from the 4th ventricle, where does CSF exit?
may exit the foramen of Luschka laterally or the foramen of Magendie medially into the subarachnoid space..
What happens when CSF passes the foramen of Magendie ?
filling of subarachnoid space
what is the cerebellomedullary cistern
the level at which CSF enters the subarachnoid space
What is CSF flow largely dependent on?
the cardiac cycle
During systole, what happens to the brain vasaculture
expands and compresses the lateral the 3rd ventricle, forcing CSF down the cerebral aqueduct
What happens to CSF flow in diastole
CSF flows down the cerebral aqueduct
How is CSF reabsorbed into the bloodstream?
outpouchings into the superior sagittal sinus = arachnoid granulations
what is the pressure dependent gradient for CSF
when the CSF pressure is greater than the venous pressure, CSF will flow into the superior sagittal sinus
even if CSF is lower than the venous pressure, the arachnoid villi will not ..?
let blood pass into the venous system
where does CSF flow after the superior sagittal sinus?
transverse sinus via the confluence of the sinus’s
