2. • Cerebrospinal fluid (CSF) is a clear fluid
present in the ventricles of the brain, the
central canal of the spinal cord, and the
subarachnoid space.
• CSF is produced in the brain by
modified ependymal cells in the choroid
plexus (approx. 50-70%), and the remainder is
formed around blood vessels and along
ventricular walls.
3. Functions of CSF
•
•
•
•
•
Protects, lubricates the brain
Provides nutrients, removes waste
90-150 ml adult
10-60 ml in newborn
Modulates pressure changes (Buoyancy)
Serves as a chemical buffer to maintain
constant ionic environment
Serves as a transport medium for nutrients
and metabolites, endocrine substances and
even neurotransmitters
4. Circulation of CSF
Lateral ventricles
interventricular foramen of Monroe
third ventricle
mesencephalic aqueduct
(aqueduct of Sylvius)
fourth ventricle
spinal cord central canal;
also, out the lateral apertures to the subarachnoid space to the
venous system
7. •
Appearance
• Normal - Crystal clear, colorless
• Descriptive Terms – hazy, cloudy, turbid, milky, bloody, xanthrochromic
• Often are quantitated – slight, moderate, marked, or grossly.
• Clots indicate traumat tap
• pellicle formation –cobweb
• Milky – increased lipids
• Oily – contaminated with x-ray
–
media
8.
9. • Xanthrochromic – Yellowing discoloration
of supernatent (may be pinkish, or orange).
• Most commonly due to presence of ‘old’ blood.
• Other causes include increased bilirubin,
carotene, proteins, melanoma
10. Traumatic collection vs
cerebral hemorrhage
• Cerebral hemorrhage
• Even distribution of blood in the numbered tubes
• Clot formation possible
• Xanthrochromic supernatent
• – RBCs must have been in CSF @ 2+ hours
• - D-dimer, fibrin degradation product from hemorrhage site
• Microscopic presence of erythrophages, or siderophages,
Hemosiderin granules
11. Lumbar puncture
• a lumbar puncture (or LP, and colloquially known as
a spinal tap)
• is a diagnostic procedure that is performed in order
to collect a sample of cerebrospinal fluid (CSF)
for biochemical, microbiological,
and cytological analysis
12.
13. indications
1. To obtain CSF sample for
cytological,chemical,cellular and bacteriological
examination
2. To aid in therapy by the administration of soinal
anesthetics and occasionally antibiotics or
antitumor agents or by reduction of CSF pressure
3. To inject radiopaque substance as in myelography,
or a radioactive agent , as in radionuclide
cisternography.
16. COMMON FORMS OF MENINGITIS
CONDITION
PRESSURE
LEUKOCYTE
PROTIEN
GLUCOSE
COMMENTS
Aute
bacterial
Elevated(100- 100-10,000
300)
Usually
PMN’s
100-500
Reduced <40
< 50% of
s.glucose
Gram stain or
culture
Partially
treated
Normal/eleva 5-10,000
ted
Usually
PMN’s/mono
nuclear cells
100-500
Normal/redu
ced
Gram stain or
anitgen
detectionby
agglitination
test
Viral
meningitis
Normal or
slightly
elevated
50-200
Normal or
reduced <40
Viral
cultures/PCR,
CT/MRI
Rarely >1000
cells.intiallly
PMN then
lymph
