ANATOMY - Central Nervous System Blood Supply

Question 1

What are the three main arteries which supply the brain of domestic species?

Answer 1

Internal carotid artery
Maxillary artery
Vertebral artery

Question 2

What is the circulus arteriosus (circle of Willis)?

Answer 2

Circulatory anastomoses surrounding the hypothalamus

Question 3

Which four arteries make up the circulus arteriosus (circle of Willis)?

Answer 3

Rostral communicating artery
Rostral cerebral arteries
Caudal communicating arteries
Basilar artery

Question 4

Which three arteries supply the cerebrum?

Answer 4

Rostral cerebral arteries
Middle cerebral arteries
Caudal cerebral arteries

Question 5

Which two arteries supply the cerebellum?

Answer 5

Rostral cerebellar artery
Caudal cerebellar artery

Question 6

In which two domestic species is the brain supplied by the internal carotid and the vertebral arteries?

Answer 6

Dogs
Horses

Question 7

Which three arteries branch from the internal carotid artery?

Answer 7

Rostral cerebral arteries
Middle cerebral arteries
Caudal communicating arteries

Question 8

Which two arteries branch from the caudal communicating arteries?

Answer 8

Caudal cerebral arteries
Rostral cerebellar arteries

Question 9

Which artery is formed by the fusion of the vertebral arteries at the base of the skull?

Answer 9

Basilar artery

Question 10

Which artery branches from the basilar artery?

Answer 10

Caudal cerebellar arteries

Question 11

In which three domestic species is the brain supplied by the maxillary and vertebral arteries?

Answer 11

Cats
Sheep
Cattle

Question 12

Why is it not recommended to use mouth gags in cats?

Answer 12

In cats the maxillary artery is the main source of blood for the brain and retinae, and mouth gags can cause compression of this artery resulting in central neurological deficits and blindness

Question 13

What is ritual slaughter?

Answer 13

Ritual slaughter is the single, rapid cut of the neck which severs the carotid arteries and jugular veins

Question 14

Why do cattle lose consciousness at a slower rate compared to sheep following ritual slaughter?

Answer 14

In sheep, the maxillary artery supplies the majority of the brain however, in cattle, the vertebral and maxillary blood mix in all parts of the brain. Because the maxillary artery is a branch of the external carotid artery, when the carotid is severed sheep will lose consciousness, however cattle remain conscious for longer as the vertebral artery is not severed so their brain will still have a blood supply

Question 15

What is the rete mirabile?

Answer 15

Network of blood vessels located in the cavernous sinus of ruminants

Question 16

What is the main function of the rete mirabile?

Answer 16

Thermoregulation

Question 17

(T/F) The veins of the central nervous system (CNS) do not have valves

Answer 17

TRUE.

Question 18

What are venous sinuses?

Answer 18

Venous sinuses are spaces between the outer periosteal and inner meningeal layers of the dura mater which drain venous blood from the central nervous system

Question 19

Which three venous sinuses make up the dorsal sinus system?

Answer 19

Dorsal sagittal sinus
Straight sinus
Transverse sinus

Question 20

Which three venous sinuses make up the ventral sinus system?

Answer 20

Cavernous sinus
Dorsal petrosal sinus
Ventral petrosal sinus

Question 21

Which venous sinus connects the dorsal and ventral sinus systems?

Answer 21

Sigmoid sinus

Question 22

Which vein does the sigmoid sinus drain into?

Answer 22

Maxillary vein into the systemic circulation

Question 23

Which venous sinuses drain into the cavernous sinus?

Answer 23

Dorsal petrosal sinus
Ventral petrosal sinus

Question 24

Describe the superficial arterial blood flow to the spinal cord

Answer 24

Aorta -> Segmental arteries -> Dorsal and Ventral root arteries -> Irregular arterial ring -> Dorsolateral spinal arteries -> Ventral spinal artery -> Anastomosing arteries

Question 25

What is the name used for the segmental arteries in the cervical region of the spinal cord?

Answer 25

Vertebral arteries

Question 26

What is the name used for the segmental arteries in the thoracic region of the spinal cord?

Answer 26

Intercostal arteries

Question 27

What is the name used for the segmental arteries in the lumbar region of the spinal cord?

Answer 27

Lumbar arteries

Question 28

What are the two deep arteries of the spinal cord?

Answer 28

Radial artery
Vertical artery

Question 29

From which superficial artery does the radial artery branch from?

Answer 29

Irregular arterial ring

Question 30

From which superficial artery does the vertical artery branch from?

Answer 30

Ventral spinal artery

Question 31

Which deep artery supplies the white matter and outer region of the grey matter of the spinal cord?

Answer 31

Radial artery

Question 32

Which deep artery supplies the grey matter of the spinal cord?

Answer 32

Vertical artery

Question 33

What is a fibrocartilaginous embolism?

Answer 33

When a small piece of cartilage from the intervertebral disc blocks one of the spinal arteries causing infarction of the region of the spinal cord that is supplied by that artery

Question 34

Which region of the spinal cord drains into the vertebral vein?

Answer 34

Cervical region

Question 35

Which region of the spinal cord drains into the azygos vein?

Answer 35

Thoracic region

Question 36

Which region of the spinal cord drains into the caudal vena cava?

Answer 36

Lumbar region