Day 3 - 5/30

Question 1

Dura mater

Answer 1

tough outer layer, keeping ventricle in place by skull and vertebral column

makes sure hemispheres do not bump

Question 2

What is the point of a sinus?

Answer 2

“Storm sewer” - points at which used up fluid goes back to heart

Question 3

What are the names of the two divisions when the dura mater outer layer splits?

Answer 3

falx cerebri (longitudinal fissure) and tantrum cerebelli

Question 4

Where is the falx cerebri and fx?

Answer 4

in the longitudinal fissure

ensures the two hemispheres will not bump

Question 5

Where is the tantrum cerebelli and fx?

Answer 5

cushions cerebellum over entire top of cerebellum

Question 6

What is the order of the meninges from outside in?

Answer 6

dura –> arachnoid (subarachnoid) –> pia mater

Question 7

Describe the arachnoid mater and fx.

Answer 7

contains a subarachnoid space where CSF actually circulates.

Villi poke through arachnoid into the superior sagittal sinus with tiny granulations for CSF to drain

Question 8

What is Pia mater and fx?

Answer 8

very thin layer of connective tissue between arachnoid mater and NS. Closely to brain and SC.

Question 9

What is CSF?

Answer 9

Similar to plasma of blood but without elements

Question 10

Describe the circulation from heart and back to heart of CSF.

Answer 10

begin: heart –> ventricles 1 & 2 (always goes through choroid plexus in each ventricle to remove formed elements) –> interventircular foreamen –> third ventricle –> cerebral aqueduct –> fourth ventricle –> 2 lateral and 1 median foreamen –> subarachnoid space –> villi –> granulations –>superior sagittal sinus –> reabsorbed into blood stream through jugular vein –> end: heart

Question 11

Hydrocephalus

Answer 11

Cerebral aqueduct gets squeezed – ventricles swell – cells shrink – eventually die if continually squeezed between CSF pathway and bone

Question 12

Meningitis

Answer 12

penetrates dura mater and outer meninges –> inflammation –> extra CSF –> squeezing –> gets through pia mater and attacks NS cells of outer brain

Question 13

Where does the underneath of the temporal lobe, occipital lobe and all of brainstem get blood supply from?

Answer 13

Posterior

Question 14

Where does the frontal lobe, top of temporal and parietal get blood supply from?

Answer 14

Anterior

Question 15

Describe the blood circulation of the anterior supply

Answer 15

aortic arch >vertebral Aa- in front of medulla > posterior inferior cerebellar A > vertebral Aa connect to form basilar A before pons > anterior inferior cerebellar A > anterior superior A > basilar splits into 2 at top of pons> posterior superior A

Question 16

Describe the blood circulation of the posterior blood supply

Answer 16

internal carotid > splits into anterior and middle cerebellar Aa
Anterior - longitudinal fissure and supplies med. surface of frontal/parietal and limbic lobe

Middle - goes lateral and supplies lateral frontal/parietal and lateral/top of temporal