Anatomy (Cranium, Meninges, Cranial Nerves)

Front 1

how do veins of the brain (venous sinuses) deal with high intracranial pressure?

Back 1

rigid walls composed of dura

Front 2

how is the distension of arteries in the brain counteracted during systoly?

Back 2

rise in intracranial pressure

Front 3

what is an aneurysm?

Back 3

localized distension of an artery
(if broken, can lead to fatal hemorrhaging)

Front 4

what are the most common sites for aneurysms?

Back 4

bifurcation of aorta
circle of willis

Front 5

what is the pachymeninx?

Back 5

dura mater

Front 6

what layer of meninges stays closely adherent to the brain?

Back 6

pia mater

Front 7

what are leptomeninges?

Back 7

arachnoid mater
pia mater

Front 8

what are the two layers of the dura mater?

Back 8

outer fibrous layer
inner serous layer

Front 9

what is the function of the outer fibrous layer of dura mater?

Back 9

binds meninges and brain to the skull

(outer layer = periosteum)

Front 10

where does the falx cerebri start?

Back 10

crista galli

Front 11

what sinus is contained or formed by the falx cerebri?

Back 11

superior sagittal sinus

Front 12

what structure forms an incomplete roof over the posterior cranial fossa?

Back 12

tentorium cerebri

Front 13

what runs through the opening in the tentorium cerebri?

Back 13

mid brain, to reach the diencephalon

Front 14

what is the normal flow of blood in the venous sinuses starting at the superior sagittal sinus?

Back 14

superior sagittal sinus -> right transverse sinus -> sigmoid sinus -> internal jugular vein

Front 15

what drains CSF from the subarachnoid space to the venous sinuses?

Back 15

arachnoid villi

Front 16

what are arachnoid granulations?

Back 16

clumps of arachnoid villi which have gathered together and calcified with age

Front 17

what is the path of flow through the venous sinuses, starting at the inferior sagittal sinus?

Back 17

inferior sagittal sinus -> straight sinus -> left transverse sinus -> sigmoid sinus -> internal jugular vein

Front 18

into what does the great cerebral vein drain?

Back 18

inferior sagittal sinus

Front 19

what is an alternative name for the great cerebral vein?

Back 19

vein of Galen

Front 20

which jugular foramen is usually bigger? why?

Back 20

right jugular foramen

usually carries drainage from the superior sagittal sinus

Front 21

what is the confluence of the sinuses?

Back 21

anatomical variation in the dural sinuses, in which the superior sagittal and straight sinuses join and empty equally into both the right and left transverse sinuses

Front 22

where is the cavernous sinus located?

Back 22

on the base of the skull, on either side of the sella turcica

Front 23

what cranial nerves are contained in the cavernous sinus?

Back 23

CN III (Oculomotor N.)
CN IV (Trochlear)
CN V (Trigeminal)
CN VI (Abducens)

Front 24

what is contained in the cavernous sinus?

Back 24

CN III (Oculomotor N.)
CN IV (Trochlear)
CN V (Trigeminal)
CN VI (Abducens)
Internal Carotid Artery

Front 25

where do the superior ophthalmic veins drain?

Back 25

cavernous sinus

Front 26

where do the inferior ophthalmic veins drain?

Back 26

cavernous sinus

Front 27

through what structure is the cavernous sinus connected to the internal jugular vein?

Back 27

inferior petrosal sinus

Front 28

what connects the two cavernous sinuses together?

Back 28

anterior and posterior intercavernous sinuses

(anterior is anterior to the pituitary gland, while posterior is posterior to the pituitary gland)

Front 29

what forms the roof of the pituitary fossa? what runs through this structure?

Back 29

diaphragma sellae
(pituitary stalk)

Front 30

where do veins from the lower part of the brain drain?

Back 30

into cavernous sinuses

Front 31

what is the first branch of the internal carotid artery?

Back 31

ophthalmic artery

Front 32

where does the ophthalmic artery run?

Back 32

into the optic canal
with the optic nerve

Front 33

what are the three terminal branches of the internal carotid artery?

Back 33

anterior cerebral artery
middle cerebral artery
posterior communicating artery

Front 34

what artery gives out branches to the pituitary gland and adjacent structures?

Back 34

internal carotid artery
(before it breaks into terminal branches)

Front 35

through what structure does the vertebral artery enter the skull?

Back 35

foramen magnum

Front 36

to what arteries does each vertebral artery give rise before both join together?

Back 36

anterior spinal artery
posterior spinal artery
posterior inferior cerebellar artery

Front 37

what arteries join to form the basilar artery?

Back 37

right and left vertebral arteries

Front 38

where does the basilar artery lie?

Back 38

on the clivus
ventral to the pons of the brainstem

Front 39

what are the branches of the basilar artery?

Back 39

anterior inferior cerebellar arteries
superior cerebellar arteries
posterior cerebral arteries

Front 40

what are the terminal branches of the basilar artery?

Back 40

superior cerebellar arteries
posterior cerebral arteries

Front 41

what forms the circle of Willis?

Back 41

left and right anterior cerebral arteries
anterior communicating artery
left and right internal carotid arteries
left and right posterior cerebral arteries
left and right posterior communicating arteries

Front 42

what is connected by the anterior communicating artery?

Back 42

left and right anterior cerebral arteries

Front 43

what is connected by each of the posterior communicating arteries?

Back 43

internal carotid artery with posterior cerebral artery

Front 44

what is the name for the anastomosis between all arteries supplying the brain?

Back 44

circle of willis

Front 45

what is significant pathologically about the circle of Willis?

Back 45

nearly all aneurysms in the brain occur at some point in the circle of Willis

Front 46

what is the only cranial nerve that doesn't leave the brain on its ventral surface?

Back 46

trochlear nerve (CN IV)

--exits from dorsal side of brain stem--

Front 47

what is cranial nerve I?

Back 47

Olfactory Nerve

Front 48

what is innervated by CN I?

Back 48

sensory to the nose
(smell)

Front 49

where do the axons from the olfactory mucosa travel?

Back 49

to olfactory bulb
(sitting on cribriform plate)

Front 50

what is cranial nerve II?

Back 50

Optic Nerve

Front 51

what is innervated by CN II?

Back 51

sensory to retina

(carries visual signals from retina)

Front 52

which cranial nerve has a "sleeve" of meninges (at least partially)?

Back 52

optic nerve (CN II)

Front 53

from what does the optic nerve develop?

Back 53

prolongations of the brain, called optic stalks

Front 54

fibers of which cranial nerve absolutely will not grow back if cut?

Back 54

optic nerve (CN II)

Front 55

what is the optic chiasma?

Back 55

part of the brain where the optic nerves cross/share fibers

Front 56

which visual field of each eye is innervated by the optic nerve of the opposite side?

Back 56

temporal visual field

Front 57

which retinal field of each eye is innervated by the optic nerve of the opposite side?

Back 57

nasal retinal field

Front 58

what visual defects are experienced if the right optic nerve is cut?

Back 58

complete blindness in the right eye

Front 59

what visual defects are experienced if the optic chiasma is cut?

Back 59

bitemporal (heteronymous) hemianopia

blindness in both temporal visual fields
or
blindness in both nasal retinal fields

Front 60

what visual defects are experienced if the right optic tract is cut?

Back 60

homonymous hemianopia

blindness in left temporal visual field and blindness in right nasal visual field
or
blindness in left nasal retinal field and blindness in right temporal retinal field

Front 61

what visual defects are experienced if the right visual cortex has a lesion?

Back 61

homonymous hemianopia

blindness in left temporal visual field and blindness in right nasal visual field
or
blindness in left nasal retinal field and blindness in right temporal retinal field

Front 62

what is cranial nerve III?

Back 62

oculomotor nerve

Front 63

what is innervated by CN III?

Back 63

most movements of the eyeball (except abductor and superior oblique muscles)
constriction of pupil
levator palpebrae superioris

Front 64

what is cranial nerve IV?

Back 64

trochlear nerve

Front 65

what is innervated by CN IV?

Back 65

motor to superior oblique muscle of the eye

Front 66

what is cranial nerve VI?

Back 66

abducens nerve

Front 67

what is innervated by CN VI?

Back 67

motor to lateral rectus muscle of the eye

Front 68

how is the occulomotor nerve tested?

Back 68

patient holds head still and follows physician's finger with only eye movement

Front 69

what is the highest nerve in the cavernous sinus?

Back 69

occulomotor nerve (CN III)

Front 70

between what two arteries does the occulomotor nerve (CN III) pass?

Back 70

superior cerebellar artery
posterior cerebral arteries

Front 71

where does the occulomotor nerve (CN III) penetrate the dura mater?

Back 71

posterior to the clinoid process

Front 72

what are the two branches of the oculomotor nerve (CN III) after it enters the orbit?

Back 72

superior division
inferior division

Front 73

through what structure does the oculomotor nerve (CN III) enter the orbit?

Back 73

superior orbital fissure

Front 74

what pierces the dura posterior to CN III?

Back 74

trochlear nerve (CN IV)

Front 75

what lies below CN III in the cavernous sinus?

Back 75

trochlear nerve (CN IV)

Front 76

through what does CN IV (trochlear nerve) enter the orbit?

Back 76

superior portion of orbital fissure

Front 77

where does CN VI leave the brain?

Back 77

lower border of the pons in the posterior cranial fossa

Front 78

where does CN VI pierce the dura?

Back 78

on the clivus

Front 79

over what does CN VI cross to enter the cavernous sinus?

Back 79

ridge of the petrous portion of the temporal bone

Front 80

through what structure does CN VI enter the orbit?

Back 80

lower part of superior orbital fissure

Front 81

what is Meckel's cave?

Back 81

aka cavum trigeminale

a diverticulum of dura carried by the trigeminal nerve from the posterior cranial fossa

Front 82

what is cranial nerve V?

Back 82

trigeminal nerve

Front 83

what is innervated by CN V?

Back 83

sensory to the face

motor to muscles of mastication

Front 84

what muscles are innervated by CN V?

Back 84

masseter
temporalis
medial and lateral pterygoid
mylohyoid
anterior belly of digastric muscle
tensor veli palatini
tensor tympani

Front 85

where does the trigeminal nerve (CN V) enlarge to form its ganglion?

Back 85

in the middle cranial fossa

over the roof of the carotid canal

Front 86

what are the three branches of CN V?

Back 86

V1 - Ophthalmic branch
V2 - Maxillary branch
V3 - Mandibular branch

Front 87

where do the three branches of CN V pierce the dura?

Back 87

in the cavernous sinus

Front 88

through what does the ophthalmic division (V1) of the trigeminal nerve enter the orbit?

Back 88

superior orbital fissure

Front 89

what are the branches of the V1?

Back 89

frontal nerve
lacrimal nerve
nasociliary nerve

Front 90

through what structure does the maxillary division (V2) of the trigeminal nerve leave the cranium?

Back 90

foramen rotundum

Front 91

through what structure does the mandibular division (V3) of the trigeminal nerve leave the cranium?

Back 91

foramen ovale

Front 92

what accompanies the V3 through the foramen ovale?

Back 92

lesser petrosal nerve

Front 93

what is cranial nerve VII?

Back 93

facial nerve

Front 94

what is cranial nerve VIII?

Back 94

vestibulocochlear nerve

Front 95

what two cranial nerves run into the auditory meatus?

Back 95

CN VII (Facial Nerve)
CN VIII (Vestibulocochlear Nerve)

Front 96

what is the nervus intermedius?

Back 96

sensory and parasympathetic fibers of the facial nerve, which travels between the facial and vestibulocochlear nerves and then continues to form the chorda tympani and greater petrosal nerve

Front 97

what nerve forms the chorda tympani?

Back 97

nervus intermedius

Front 98

what nerve forms the greater petrosal nerve?

Back 98

nervus intermedius

Front 99

what are the branches of cranial nerve VIII (vestibulocochlear nerve) inside the internal auditory meatus?

Back 99

vestibular branch
cochlear branch

Front 100

what is cranial nerve IX?

Back 100

glossopharyngeal nerve

Front 101

where does the glossopharyngeal nerve travel within the skull?

Back 101

arises from the medulla and immediately exits via the jugular foramen

Front 102

through what structure does the glossopharyngeal nerve (CN IX) exit the skull?

Back 102

jugular foramen

Front 103

what is cranial nerve X?

Back 103

vagus nerve

Front 104

what accompanies the vagus nerve (CN X) through the jugular foramen?

Back 104

cranial portion of CN XI (accessory nerve)

Front 105

through what structure does the vagus nerve exit the skull?

Back 105

jugular foramen

Front 106

what is cranial nerve XI?

Back 106

accessory nerve

Front 107

what are the two portions of CN XI?

Back 107

cranial portion
spinal portion

Front 108

from where does the spinal portion of CN XI arise?

Back 108

upper 5 segments of the spinal cord

Front 109

through what structure does the spinal portion of CN XI enter the skull?

Back 109

foramen magnum

Front 110

through what structure does the spinal portion of CN XI exit the skull?

Back 110

jugular foramen

Front 111

what is innervated by the spinal portion of CN XI?

Back 111

SCM
trapezius

Front 112

through what structure does the cranial portion of CN XI exit the skull?

Back 112

jugular foramen

Front 113

what is innervated by the cranial portion of CN XI?

Back 113

voluntary muscles of the larynx, etc.

Front 114

what is cranial nerve XII?

Back 114

hypoglossal nerve

Front 115

from where does the hypoglossal nerve arise?

Back 115

side of medulla

Front 116

through what structure does CN XII exit the skull?

Back 116

hypoglossal canal
aka anterior condylar canal

Front 117

how does one test for lesions of CN V?

Back 117

sharp and dull sensations in different parts of face
movement of jaw

Front 118

how does one test for lesions of CN VII?

Back 118

facial expressions (screwing up eyes, raising eyebrows, smiling, whistling)

Front 119

how does one test for lesions of CN VIII?

Back 119

hearing and balance

(rubbing fingers together, closing eyes and standing)

Front 120

how can one test for lesions of CN IX?

Back 120

test for gag reflex

Front 121

how can one test for lesions of CN X?

Back 121

inability to swallow
hoarse voice

Front 122

how can one test for lesions of CN XI?

Back 122

shrug shoulders and turn head against resistance

Front 123

how can one test for lesions of CN XII?

Back 123

movement and protrusion of tongue

(tongue will deviate toward side of lesion when protruded)