neuro2and3 Flashcards
at what spinal levels is LP generally performed?
between L3/4 or L4/5
ASIS level
L3/4
where does spinal cord end
L1/2
glucose content of csf versus blood
glucose content of csf is 2/3 that of blood
opening pressure of LP
60 to 150 mm H20
xanthochromia
yellow csf; demonstrates in vivo intrathecal hemorrhage (as opposed to a traumatic tap)
contraindic to LP
closure of the fourth ventricle and quadrigeminal cistern
xanthochromia indicates
subarachnoid hemorrhage or hemorrhagic encephalitis
fat on t1 versus t2 MRI
fat bright on t1, so myelin-containing white matter is bright
water (csf) on t1 versus t2
water is dark on T1 and bright on T2
FLAIR mri
fluid-attenuated inversion recovery; like T2 but signal from CSF is inverted so that it is low
DWI
diffusion weighted imaging; shows cellular toxicity ; used for stroke (pos within half an hour)
best screening image sequence for most pathological processes in the CNS
FLAIR
susceptibility-weighted sequence MRI
susceptible to disruption (turns black) from some substance like calcium, bone, and the bood breakdown products ferritin and hemosiderin
contrast enhancement on brain CT
indicates local disruption f the BBB