chapter 15 Flashcards
what is meninges
layers surrounding the brain and the spinal cord
whats meningitis
Inflammation of meninges
whats the purpose of meninges
- Enclose and protect blood vessels and brain and spinal cord
- Form major venous drainage
- Contain CSF between layers
what are the layers of meninges (superficial to deep)
dura mater, Arachnoid mater, Pia mater
what is the Pia and dura mater made of
pia- areolar CT
dura- Dense irregular CT
what are the layers of dura mater (superficial to deep)
Periosteal layer
Meningeal layer
what does the periosteal layer do
sticks to skull
whats dural septa
Infoldings of meningeal layer
what are the two dural septa and where are they
Falx cerebri
- Infolding in between cerebral hemisphere
Tentorium cerebelli
- Infolding lower and below the falx cerebri
- Separates cerebrum and cerebellum
what are the 6 dural venous sinuses and where are they
Superior sagittal sinus
- Under skull bone in the middle of hemispheres
Inferior sagittal sinus
- Inferior edge of falx cerebri
Straight sinus
- Inferior sagittal sinus drains into it
Confluence of sinuses
- Superior and inferior sagittal sinus drain into it
- Where superior sagittal sinus and straight sinus meet
Left and right transverse sinuses
- Wrap around left and right of brain
Left and right sigmoid sinus
- Blood comes from transverse sinus
- S-shaped
where does the CSF go into the spinal cord
the jugular foramen
what is CSF made of
mostly water and blood plasma
what are the functions of CSF
Buoyancy (lets brain float)
shock absorber
environmental stability (helps keep other fluids away from the rest of the body)
where is CSF found
Subarachnoid space and the ventricles
what are the 4 ventricles
2 lateral ventricles
third ventricle
fourth ventricle
What makes CSF and where is it found
the choroid plexus and in the ventricles
what is the circulation of CSF starting in the lateral ventricles
-Lateral ventricle (choroid plexus)
- Interventricular foramen (Hole that connects lateral and third ventricles)
-Third ventricle (choroid plexus)
-Cerebral aqueduct
-Fourth ventricle (choroid plexus)
-Central canal of spinal cord
OR
-Subarachnoid space (outside of brain)
-Arachnoid villi
-Superior sagittal sinus
what is hydrocephalus
-Something is clogging up the draining of CSF
-The amount of CSF produced is more than what is being drained
what are the 2 layers of the BBB and what do they do
Endothelial cells
-Epithelial tissue
Perivascular feet of astrocyte
-Astrocyte
-Carriers nutrients in and waste out
what are the components of the BBB
Endothelial cells of capillaries → tight junctions
-Makes sure things go through the cell
Continuous basement membrane
- No holes
Perivascular feet of astrocytes
is the BBB a complete barrier, what can get through?
Not a complete barrier
- Lipid soluble compounds can sneak in
what are the gaps in the BBB
Gaps
- Choroid plexus
- Hypothalamus and pineal gland
whats the difference between grey and white matter
White is myelinated axons
Grey is cell bodies
what are the grey mater in the brain and the spinal cord
brain:
Cortex (Outside of brain)
Centers / nuclei
spinal cord:
Horns
