meninges

Question 1

What is CSF

Answer 1

Fluid surrounding the brain

similar to ocean water

Question 2

where is csf made? majority at? continual?

Answer 2

made at the choroid plexuses of the ventricles
Lateral ventricles are largest and produce the most
also made at 3rd and 4th ventricles
will produce CSF continually, can lead to complications

Question 3

path of CSF to circulation

Answer 3

produced at the lateral ventricles>will exit via the intraventricular foramen and enter the 3rd ventricle>exits here via the cerebral aqueduct into the 4th ventricle> CSF enters circulation in subarachnoid space via the median and lateral apertures

Question 4

meningial layers superficial to deep

Answer 4

dura>arachnoid>pia mater

Question 5

arachnoid granulations, purpose and common location?

Answer 5

150cc of CSF in circulation, 500 made a day> some must be moved to venous circulation
subarachnoid space that contains the CSF will extend into the granulations and move CSF into venous circulation by transport through epithelial cells (active transport) or CSF can move between the cells as well
This action mostly occurs at superior sag sinus and its lat lacunae

Question 6

lateral ventricles

Answer 6

Largest of the ventricles, produces the most CSF
located deep within the brain> 2 of them a R and L
will produce CSF at choroid plexus and move it to 3rd ventricle via foramen morno/interventricular foramen

Question 7

what drives CSF into venous circulation at the arachnoid granules

Answer 7

positive pressure surrounding the brain and active transport

Question 8

Blockage in the CSF flow?

Answer 8

could possibly occur in any of the ventricles, foramen, or within the subarachnoid space
would result in a build-up of pressure as the choroid plexuses do not stop CSF production
this could crush nerves or even stop blood flow

Question 9

dura mater, can form?

Answer 9

directly beneath the bone with two layers
periosteal (upper) and meningeal (lower)
splitting of the two layers can create space for dural sinuses (Venous sinuses)

Question 10

bridging vv

Answer 10

vv that go between the subarachnoid space and into venous sinusoids

Question 11

subdural hematoma

Answer 11

possible injury to vessels beneath the dura mater
blood will pool and create a space btwn the dura and arachnoid mater
mostly due to vv but can be aa as well
rough appearance on scan> blood can go into the gyri/sulci of the brain

Question 11

subdural hematoma, imaged appearence?

Answer 11

possible injury to vessels beneath the dura mater
blood will pool and create a space btwn the dura and arachnoid mater
mostly due to vv- especially the superior cerebral vv at the superior saggital sinus
blood will follow the paths of the sulci/gyri=not a smooth convexity when imaged

Question 12

epidural hematoma

Answer 12

would be the rupture of a vessel above the dura mater
typically branches of the middle meningeal aa
blood can pool and separate the periosteal dura from from skull
will also create P to push onto the brain preventing blood from entering the area

Question 13

cerebral flax

Answer 13

largest infolding of the dura mater
lies within the longitudinal cerebral fissure all the way down to the corpus callosum
divides the L and R hemispheres

Question 14

confluence of sinuses

Answer 14

where all the venous sinuses meet

gives rise to the transverse sinus that then becomes the sogmoid and eventually the int jugular

Question 15

cerebral flax anatomy

Answer 15

superior aspect: superior saggital sinus
Lateral aspect: transverse sinus
also has the cerebellar tentorium to seperate the cerebrum from the cerebellum

Question 16

dura/brian inn

Answer 16

dura receives sensory inn from CNV branches, can feel pain

Brain has no sensory info=doesnt feel pain

Question 17

danger of the pterion

Answer 17

weak point and the frontal branch of middle meningeal aa beneath it
could be ruptured if pterion struck
would lead to a epidural hematoma

Question 18

danger triangle, why would dentists care?

Answer 18

venous drainage of this area goes back to the cavernous sinus
provides a route for infection to reach the cavernous sinus and the brain
infections of maxillary teeth could potentially take this route