Meninges, Ventricles, Vasculature

Question 1

Dura Mater

Answer 1

The strong outer “envelope” between the skull and the arachnoid layer
forms Dural Reflections and Dural Sinuses
has pain receptors

Question 2

Dural Reflections

Answer 2

Folds in the Dura that partially separate different intracranial compartments

Question 3

Falx Cerebri

Answer 3

fold that separates the two cerebral hemisphere

Question 4

Falx Cerebelli

Answer 4

partially separates the cerebelli

Question 5

Tentorium Cerebelli

Answer 5

fold that separates the cerebellum and cerebrum

- defines the supratentorial (contains cerebrum) and infratentorial compartment (cerebellum and brainstem)

Question 6

Diaphragma Sellae

Answer 6

reflection that cover the pitu fossa. The infundibulum goes through a small hole here

Question 7

Tentorial Notch

Answer 7

the space in the tentorium through which the brain stem passes

Question 8

Dural Sinuses

Answer 8

where the cerebral veins empty
- Superior and Inferior Sagittal sinus
- Right and Left Transverse sinus
- Straight sinus
these drain into the confluence of sinuses
- sigmoid sinus

Question 9

Arachnoid

Answer 9

part of leptomeninges
attached to the inside of the dura
does not line the brain down into its sulci
CSF flows under this membrane

Question 10

Arachnoid Trabecula

Answer 10

strands of connective tissue that loosely connect the arachnoid and pia mater
CSF contained here

Question 11

Arachnoid Mater-cisterns

Answer 11

openings in subarachnoid space of the brain created by a separation of the arachnoid and pia mater
filled with CSF
- Cerebellomedullary cistern
- Pontine cistern

Question 12

Arachnoid Villi

Answer 12

small protrusions of the arachnoid that reach into the dural sinus
where CSF moves from subarachnoid space –> through arachnoid villi –> dural sinus

Question 13

Arachnoid Granulations

Answer 13

collection of arachnoid villi

form pacchionian bodies with age

Question 14

Epidural Space

Answer 14

between dura and skull
may be opened up by blood from a ruptured meningeal artery/torn dural venous sinus
spinal meninges do have a normal epidural space

Question 15

Subdural Space

Answer 15

may be opened up by blood from a vein that tears as it crosses the arachnoid to enter a dural sinus

Question 16

Ventricles (flow of CSF)

Answer 16

Lateral ventricles –> foramen of Monro –> 3rd ventricle –> cerebral aqueduct –> 4th ventricle –> foramen of Magendie and foramen of Luschka –> Cistern Magna and Pontine Cistern –> spinal cord central canal –> tentorial notch –> arachnoid villi –> superior sagittal sinus

Question 17

Choroid Plexus

Answer 17

modified capillaries that synthesise CSF (only in ventricles, not foramens)

Question 18

Anterior Cerebral Artery

Answer 18

provides blood to the medial surface of each cerebral hemisphere

Question 19

Middle Cerebral Artery

Answer 19

provides blood to the lateral surface of each cerebral hemisphere

Question 20

Posterior Cerebral Artery

Answer 20

provides blood to the medial and lateral surface of each occipital lobe

Question 21

Blood Brain Barrier (function)

Answer 21

• protects brain from ‘foreign substances’ that can infect or damage the brain
• protects the brain from systemic hormones and neurotransmitters
• maintains a constant environment

Question 22

Endothelial cells

Answer 22

cells that have tight junctions between them that restrict the diffusion of microscopic objects and large/hydrophilic molecules into CSF
allows diffusion of hydrophobic molecules eg O2

Question 23

Astrocytes

Answer 23

cell projections called astrocytic end feet surround the endothelial cells of the BBB
provides biochemical support

Question 24

Arachnoid Mater

Answer 24

tight junctions that keep substances from entering the brain

Question 25

Subfornical Organ

Answer 25

small nodule in the anterior, superior corner of the third ventricle
controls fluid balance and drinking behavior