3. Venous drainage of the CNS

Question 1

Name the constituents of the DORSAL system of sinuses

Answer 1

• Dorsal sagittal sinus
• Straight sinus
• Transverse sinuses (L+R)

Question 2

Name the constituents of the VENTRAL system of sinuses

Answer 2

• Cavernous sinus
• Petrosal sinuses (dorsal + ventral)

Question 3

Name the CONNECTING sinuses

Answer 3

• Temporal + sigmoid sinuses

Question 4

DORSAL SAGITTAL SINSUS
1. Localization
2. Drainage

Answer 4

1. Dorsal aspect of the falx (whole length)
2. Dorsal cerebral veins + most diploic veins

Question 5

STRAIGHT sinus
1. Localization
2. Drainage

Answer 5

1. Caudoventral aspect of the falx
2. Great cerebral vein into the caudal part of dorsal sagittal sinus

Question 6

TRANSVERSE sinuses
1. Localization
2. Drainage

Answer 6

1. R+L sinuses join along dorsal midline
2. Drain dorsal sagittal + straight sinuses into the temporal and sigmoid sinuses

Question 7

CAVERNOUS sinus (paired L/R)
- what are its 3 connections?

Answer 7

• To ophtalmic plexus rostrally
• To maxillary vein laterally
• To other cavernous sinus medially, via intercavernous sinuses

Question 8

PETROSAL sinus - what are the roles of the dorsal vs ventral

Answer 8

DORSAL petrosal sinus:
- Drains ventral cerebral vein

VENTRAL petrosal sinus
- Joins the cavernous to the sigmoid (connecting) sinus
- Burried in the bony petro-occipital canal

Question 9

TEMPORAL & SIGMOID (connecting) sinuses

Drain what via what?

Answer 9

Drain both
- DORSAL sytem via transverse sinuses
- VENTRAL system via petrosal sinuses

Connect directly with the spinal system of sinuses

Question 10

Role of the veins of the brain

Answer 10

Drain cranial system of sinuses into the systemic circulation

Question 11

4 particularities of the veins of the brain

Answer 11

1. No valve
2. No smooth mucle (thin)
3. Lots of anastomosis
4. Not satellite to arteries

Question 12

Name the veins of the brain (cerebral, cerebellar, caudal brainstem)

Answer 12

CEREBRAL VEINS
- Superficial: Dorsal/ventral cerebral veins
- Deep: Great cerebral vein

CEREBELLAR VEINS
- Dorsal/ventral cerebellar veins

CAUDAL MEDULLA
- Medullary veins
- Pontine veins

Question 13

None of the veins are satellite to arteries, except

Answer 13

Caudal medulla

Question 14

DORSAL CEREBRAL veins
1. Drain what?
2. Lie where?
3. First four project to…

Answer 14

1. Dorsal system of sinuses
2. In the sulci
3. Dorsal sagittal sinus

Question 15

VENTRAL CEREBRAL veins
1. Drain what?
2. Project where?

Answer 15

1. Ventral system of sinuses
2. ## Dorsal petrosal sinus

Question 16

DEEP cerebral veins
1. All drain into…

Answer 16

1. Great cereberal vein

Question 17

DORSAL cerebellar vein project to

Answer 17

A corresponding transverse sinus

Question 18

VENTRAL cerebellar vein drains into

Answer 18

Sigmoid and basilar sinuses

Question 19

Summary slide 52

Question 20

What is the main component of the venous drainage to the spinal cord?

Answer 20

Longitudinal sinuses

Question 21

Describe the LONGITUDINAL SINUSES of the spinal cord

Answer 21

• Pair of 2 parallel sinuses
• Run along entire lenght of spinal cord, on ventral floor
• Diverge over i-v disc
• Converge mid-vertebral body where they occasionally anastomose

Question 22

What veins drain the longitudinal spinal sinuses into the systemic circulation?

Answer 22

Intervertebral veins

Question 23

Where do the INTERVERTEBRAL veins drain ?

Answer 23

Run parallel to nerve roots, escape canal through intervertebral foramina, then empty into:
- VERTEBRAL veins (C spine)
- AZYGOS vein (T spine)
- CAUDAL VENA CAVA (L spine)

Question 24

Which veins could be accidentally punctured during CSF collection in the AO junction?

Answer 24

Interarcuate veins

Question 25

What is the role of the INTERARCUATE veins

Answer 25

Join longitudinal spinal sinuses with a dorsal external venous plexus

Question 26

What is the role of the BASIVERTEBRAL veins

Answer 26

Join the two longitudinal spinal sinuses together and drain the vertebral bodies