Meninges (Kasper)

Question 1

list the 3 functions of the meningeal layers

Answer 1

1. protect brain and spinal cord from mechanical damage
2. provide space for CSF flow
3. conduit for vascularization of skull and cerebrum

Question 2

relationship between pia mater and arachnoid mater

Answer 2

arachnoid trabeculae extend across CSF-filled subarachnoid space to the pia mater

Question 3

relationship between pia and dura

Answer 3

denticulate ligaments

bilateral thickening of the collagenous component of the pia mater - anchoring it to the dura (helping suspend the spinal cord)

Question 4

relationship between arachnoid and dura

Answer 4

very closely related

only separate due to subdural hematoma

Question 5

layers of dura

Answer 5

periosteal (superficial)

• no epidural space in skull
• epidural space in spinal cord

meningeal (deep)

Question 6

infoldings of the dura

Answer 6

falx cerebri

tentorium cerebelli

membranous covering of the hypophyseal fossa

Question 7

arteries in the brain are enclosed by

Answer 7

pial sheath

Question 8

describe the arterial supply to the canine brain

Answer 8

main supply: internal cartoid artery

• supplies the rostral and middle cerebral arteries
• supplies the circle of willis

alternative supply: vertebral arteries

• supply the basilar artery
• supplies the rostral cerebellar and caudal cerebral arteries of the circle of willis

severance of the common carotid leads to relatively slow loss of consciousness because of the back of supply of the basilar/vertebral arteries

Question 9

why does severance of the common carotid artery lead to rapid loss of consciousness in cats?

Answer 9

cats and sheep rely on the anastomosing branch of the middle meningeal artery

• supplied by the maxillary artery
• supplied by the external carotid artery

essentially no internal carotid supplies the brain and the vertebral arteries do not supply it enough to make up for the loss

Question 10

what structures does the basilar artery supply?

Answer 10

pons

medulla oblongata

caudal cerebellum

Question 11

meningioma

Answer 11

most common primary brain tumor of cats and dogs

arises from the arachnoid mater

relatively slow-growing and treatable

Question 12

meningitis

Answer 12

viral, bacterial, or fungal

typically: granulomatous meningoencephalitis

hypercellular CSF

Question 13

difference between veins and sinuses

Answer 13

veins: within and around the brain
sinuses: between the periosteal and meningeal layers of the dura mater