Meninges, venous drainage of the brain and CSF

Question 1

what are the three protective layers of the brain

Answer 1

• dura mater
• arachnoid mater
• arachnoid trabeculae
• cerebral artery branch
• pia mater

Question 2

what is included in the dura mater and what is it

Answer 2

tough fibrous and bridges the crevices and attaches itself to the skull

branches of the middle meningeal artery (this artery is easy to rupture due to the period

Question 3

what is the arachnoid layer

Answer 3

delicate, sealed bag filled with CSF that bridges the gaps between crevices

Question 4

where is the cerebral artery branch

Answer 4

its embedded within the Pia mater

Question 5

what are cisterns

Answer 5

areas filled with CSF

Question 6

what are the four major cisterns

Answer 6

• superior cistern
• interpeduncular cistern
• cisterna pontis
• cisterna magna (cerebellomedullaris)

Question 7

what major vascular structure lies within the subarachnoid space

Answer 7

the circle of willis - a berry aneurysm on the circle of willis is a very common cause of subarachnoid haemorrhage

Question 8

what are denticulate ligaments made of

Answer 8

extensions of pia mater

Question 9

where does the venous system of the brain lie

Answer 9

subarachnoid space

Question 10

where do the veins of the brain drain into

Answer 10

the cranial venous sinuses

Question 11

what is the membrane that separates the two hemispheres and what is the membrane that lies n the posterior aspect of the cerebrum and the superior aspect of the cerebellum

Answer 11

the falx cerebri

tentorium cerebelli

Question 12

what sinus runs the length of the falx cerebri

Answer 12

the superior sagittal sinus

Question 13

what sinus runs the length of the tentorium cerebelli

Answer 13

the transverse sinus

Question 14

where the s.s.s and the t.s meet this is called the

Answer 14

confluence of sinuses

Question 15

what sinus projects from the confluence of sinus

Answer 15

the straight sinus

Question 16

what vein branches off the straight sinus

Answer 16

the great cerebral vein, then inferiorly the basal vein and superiorly the internal cerebral vein

Question 17

Cerebrospinal fluid (CSF)

Answer 17

• Clear colourless fluid which fills the ventricles of the brain surrounds the brain and spinal cord

Question 18

what are the ventricles of the brain

Answer 18

2x lateral 
inter ventricular foramen 
third ventricle 
cerebral aqueduct 
fourth ventricle

Question 19

Formation of CSF

Answer 19

• Formed in the choroid plexus (up to half from blood vessels surrounding the ventricles)
• Core of vascular Sssue (in pia) covered by an epithelium which secretes cerebrospinal fluid
  (epithelium differentiated from ependyma – classified as glial)

Question 20

CSF flows out of ventricle system into

Answer 20

subarachoid sp. via apertures in fourth ventricle through arachnoid granulations

Question 21

Hydrocephalus is caused by

Answer 21

Due to blocked transport (non-communicaSve), or to overproducSon/ blocked absorpSon of CSF (communicaSve)

resulting in enlarged cranial cavity and dilated ventricles

treated most commonly with a shunt