Neurocranium I

Question 1

dura mater

Answer 1

1) outer periosteal
2) inner meningeal layer

Question 2

arachnoid mater

Answer 2

1) outer mesothelial layer is adherent to the dura mater
2) inner trabecular layer forms leptomeningeal bridges to pia mate

Question 3

pia mater

Answer 3

1) contiguous with arachnoid trabeculae
2) intimal layer adherent to surface of brain

Question 4

epidural space

Answer 4

1) between dura mater and skull
2) in the cranium, it is only a potential space

Question 5

subdural space

Answer 5

1) between dura mater and arachnoid mater
2) only a potential space

Question 6

subarachnoid space

Answer 6

1) bridged by arachnoid trabeculae
2) blood vessels and CSF

Question 7

epidural hematoma

Answer 7

1) bleeding into the potential space between bone and dura mater
2) traumatic injury of the middle meningeal artery due to skull fracture
3) compression of the brain can be fatal

Question 8

subdural hematoma

Answer 8

1) bleeding into the potential space between the dura bater and the arachnoid
2) typically caused by violent shaking or jarring
3) small bridging veins are torn
- cerebral veins between surface of the vein and the dural sinuses
4) small children and the elderly are susceptible

Question 9

falx cerebri

Answer 9

1) two-layered projection of meningeal dura along the median plane of the cranial vault, separating the left and right cerebral hemispheres
2) anterior attachment: crista galli
3) posterior attachment: internal occipital protuberance

Question 10

falx cerebelli

Answer 10

1) two-layered projection of meningeal dura along the median plane of the cranial vault, separating the left and right cerebral hemispheres of cerebellum
2) runs along the internal occipital crest

Question 11

tentorium cerebelli

Answer 11

1) two layers of the falx cerebri separate from each other to project laterally
2) extend bilaterally from falx cerebri to the superior petrosal sulcus
3) free anterior edges form the tentorial incisura

Question 12

diaphragma sellae

Answer 12

1) dural membrane extending from the anterior clinoid processes to the posterior clinoid processes
2) covers the hypophyseal fossa (sella turcica)
3) pituitary stalk (hypophyseal infundibulum) passes through a hiatus while the gland remains beneath

Question 13

dura mater innervation

Answer 13

1) supratentorial innervation
- trigeminal nerve CN V
- sensory
2) infratentorial innervation
- vagus nerve (CNX)
- cervical spinal nerve C1-3

Question 14

meningeal blood supply

Answer 14

1) is embedded in the dura mater
-middle meningeal artery
- branch of maxillary artery from the external carotid artery
2) the arachnoid mater is avascular
- gets everything from CSF
- but the arachnoid space has vessels
3) the pia matter gets blood from arteries that pass over the surface of the cerebrum
- from internal carotid

Question 15

meningeal blood supply accessory arteries

Answer 15

1) accessory meningeal artery
2) occipital artery
3) vertebral artery
4) ascending pharyngeal artery
5) anterior ethmoidal artery
6) posterior ethmoidal artery
* no need to memorize except for middle meningeal artery

Question 16

cerebral blood supply

Answer 16

1) internal carotid
- 70% of blood supply
2) vertebral arteries
- 30% of blood supply

Question 17

cricle of willis

Answer 17

1) vertebral arteries => basilar artery => posterior cerebral arteries
2) internal carotid
=> middle cerebral arteries
=> anterior cerebral arteries
3) posterior communicating arteries
- connect posterior cerebral with internal carotid
4) anterior communicating artery (singular) connect anterior cerebral arteries

Question 18

venous drainage

Answer 18

1) blood from the cerebral cortex and meninges drains to surface veins that empty into dural venous sinuses
2) dural sinuses =/= paranasal sinuses (air-filled)

Question 19

superior sagittal sinus

Answer 19

1) formed by the separation of the meningeal dura from the periosteal dura
2) arachnoid villi (granulations when calcified)
- filled with CSF that return to the blood stream
3) drains blood from the superior portion of the brain
4) lateral projections of this sinus form lacunae whihc contain additional arachnoid villi

Question 20

superior sagittal sinus location

Answer 20

1) superior margin of the falx cerebri
2) receive blood from the outer surface of the brain

Question 21

inferior sagittal sinus

Answer 21

1) blood from medial surfaces of cerebral hemispheres

Question 22

straight sinus role

Answer 22

1) shunts blood from inferior sagittal sinus to the confluens of the sinuses

Question 23

straight sinus

Answer 23

1) receives great cerebral vein
- great vein of galen
2) drains blood from brainstem

Question 24

transverse sinuses

Answer 24

1) receives blood from the superior sagittal and the straight sinussign

Question 25

sigmoid sinuses

Answer 25

1) receive blood from transverse sinuses
2) drains into internal jugular vein

Question 26

cavernous sinuses

Answer 26

1) lie on either side of sella turcica
2) receive blood from
- sphenoparietal sinus
- superior Opthalmic vein
- interior ophthalmic vein
- pterygoid venous plexus
3) drain into superior and inferior petrosal sinuses

Question 27

contents of cavernous sinus

Answer 27

1) oculomotor nerve CNIII
2) trochlear nerve CNIV
3) abducens nerve CNVI
4) opthalmic nerve CN V1
5) portion of the maxillary nerve CN V2
6) internal carotid artery

Question 28

dural venous sinuses and CSF

Answer 28

1) superior sagittal sinus receives CSF from subarachnoid space
2) CSF flows into the sinus via arachnoid villi

Question 29

choroid plexus

Answer 29

1) CSF is ultrafiltrate of blood produced by choroid plexus of the cerebral ventricular system
2) 300 mL per day
3) highly convoluted fenestrated capillaries surrounded by ependyma
4) lies within the lumen of the ventricular system
-fluid filled space derived from embryological neural tube
5) subarachnoid space is continuous with the ventricles (cavities) within the brain
6) ventricular system is continuous with the central canal of the spinal cord

Question 30

ventricles

Answer 30

1) lateral ventricles drain the interventricular foramen (of monro) into the third ventricle
2) third ventricle connects to fourth ventricle via the cerebral aqueduct
3) from fourth ventricle, CSF can
- continue into central canal of spinal cord
- exit into subarachnoid space via:
a) lateral foramina (of luschka)
b) median foramen (of magendie)

Question 31

embryology of ventricular system

Answer 31

1) ventricular system is neural tube
2) lateral walls of the forebrain expand and protrude from both sides of the neural tube
3) lateral ventricle…????

Question 32

cranial nerves

Answer 32

1) just memorize them all

Question 33

olfactory nerve CNI

Answer 33

1) cribriform plate of the ethmoid bone
2) special sensory afferent fibers (SSA)
3) not visible in cadaver
4) project from nasal mucosa to olfactory bulb
- olfactory bulb and olfactory tract are part of the brain

Question 34

optic nerve CNII

Answer 34

1) nerve and retina are outgrowth of the brain
2) special sensory afferent fibers (SSA)
3) optic canal is where it passes through
4) left visual field maps to right side of the brain (and vice versa)
5) fibers from the nasal retina cross the midline at the optic chiasm

Question 35

oculomotor nerve CNIII

Answer 35

1) GSE
- extraocular muscles of the eye
2 ) also supplies the parasympathetic innervation of eye
- GVE
3) passes through the cavernous sinus and the superior orbital fissure

Question 36

trochlear nerve CN IV

Answer 36

1) controls the superior oblique muscle of the eye (GSE)
2) passes through the cavernous sinus and superior orbital fissure
3) only cranial nerve to originate from the posterior aspect of the brainstem

Question 37

trigeminal nerve CNV

Answer 37

1) GSA to the face, meninges, eye, nasal cavity, oral cavity, and tongue
2) single sensory ganglion with 3 divisions
- ophthalmic (passes through cavernous sinus and superior orbital fissure)
- maxillary (foramen rotundum)
- mandibular (foramen ovale)
—
1) GSE to
- muscles of mastication
- anterior belly of digastric
- mylohyoid muscle
- tensor veli palatini
- tensor tympani
2) motor innervation runs with V3

Question 38

abducens nerve CNVI

Answer 38

1) GSE to the lateral rectus muscle of the eye
2) runs freely through the cavernous sinus
3) passes through the superior orbital fissure

Question 39

facial nerve CN VII

Answer 39

1) GSE to
- muscles of facial expression
- posterior belly of the digastric m
- stylohyoid muscle
2) GVE (parasympathetic)
- submandibular, sublingual, and lacrimal glands
3) SSA from anterior 2/3 of tongue
4) GSA to oropharynx and small region around the ear
5) exits through the internal acoustic meatus
- travels through the facial canal in the temporal bone
- exits the skull through stylomastoid foramen

Question 40

vestibulocochlear nerve CN VIII

Answer 40

1) SSA to the cochlea and vestibular system
2) exits the neurocranium via internal acoustic meatus

Question 41

glossopharyngeal nerve CN IX

Answer 41

1) GSA to the pharynx and the posterior 1/3 of tongue
2) SSA fibers for the posterior 1/3 of the tongue
3) exits from jugular foramen

Question 42

vagus nerve CNX

Answer 42

1) GVE to heart, lungs, and digestive tract
2) GVA to the abdominal and thoracic viscera
3) GSE to the muscles of pharynx and larynx
4) exits through jugular foramen

Question 43

spinal accessory nerve XI

Answer 43

1) cranial component and a spinal component
2) spinal component enters from foramen magnum
3) GSE to trapezius and SCM

Question 44

hypoglossal nerve XII

Answer 44

1) somatic motor innervation to tongue muscles
2) exit the neurocranium via the hypoglossal canal

Question 45

what to know for the quiz

Answer 45

1) how it gets out of skull
2) the name of the nerve and number