Lab 2: Skull and Cranial Foramina

Question 1

what is purpose of mandibular fossa

Answer 1

jaw connects
located between styloid process and zygomatic arch

Question 2

loss of sensation on left side of face, superior to eyebrow
blinking and squinting unaffected
brow can be furrowed

which cranial nerve has tumour?

Answer 2

trigeminal
V1 = ophthalmic branch

Question 3

loss of sensation on left side of face, superior to eyebrow AND CHIN–>FOREHEAD
CANNOT FEEL HOT/COLD LIQUIDS ON ANTERIOR LEFT OF TONGUE
DIFFICULTY CHEWING ON LEFT SIDE
brow can be furrowed
blinking and squinting unaffected

which cranial nerve has tumour further grown onto?

Answer 3

V3 = mandibular
V2 = maxillary
probably on trigeminal root

Question 4

difficulty speaking
can make sounds - muscles of vocalization unaffected
difficulty making specific sounds that involve movement of tongue against palate or teeth

imaging reveals stenosis of bony canal in occipital bone
which canal? and which nerve impinged?

Answer 4

hypoglossal canal
hypoglossal nerve
pinched so affects motor - muscles of tongue

Question 5

mouth dry
ability to taste diff foods reduced
can smile and squint w/o trouble

which nerve damaged?

Answer 5

glossopharyngeal damaged
can still do facial expressions so facial nerve not affected= why asked to smile and squint (motor affects facial muscles)
but no, also salivary gland affected = glossopharyngeal

Question 6

ORIGIN - cnI olfactory
FORAMEN
FUNCTION

Answer 6

origin = brain
foramen = cribriform foramen - ethmoid
function = special sense - smell

Question 7

ORIGIN - cnII optic
FORAMEN
FUNCTION

Answer 7

origin = brain
foramen = optic canal - sphenoid
function = special sense - vision

Question 8

ORIGIN - cnIII oculomotor
FORAMEN

Answer 8

origin = midbrain
foramen = superior orbital fissure - sphenoid

Question 9

FUNCTION - cnIII oculomotor

Answer 9

motor = extraocular muscles of eye (superior, inferior and medial rectus, inferior oblique, levator palpebrae superioris)
parasympathetic = iris, pupillary constriction

Question 10

ORIGIN - cnIV trochlear
FORAMEN
FUNCTION

Answer 10

origin = midbrain
foramen = superior orbital fissure - sphenoid
function = motor - extraocular muscle, superior oblique

Question 11

ORIGIN - cnV trigeminal
FORAMEN

Answer 11

origin = PONS for all branches
V1 oph foramen = superior orbital fissure
V2 max foramen = rotundum
V3 mand foramen = ovale

Question 12

FUNCTION - V1

Answer 12

sensory - skin of upper face

Question 13

FUNCTION - V2

Answer 13

sensory - skin of middle face, upper teeth and lip

Question 14

FUNCTION - V3

Answer 14

sensory - skin of lower face, lower teeth, ant 2/3 of tongue (NOT TASTE)
motor - muscles of mastication

Question 15

what provides general sensory to tongue

Answer 15

lingual nerve of mandibular nerve (V3)

Question 16

ORIGIN - cnVI abducens
FORAMEN
FUNCTION

Answer 16

origin = pontomedullary junction
foramen = superior orbital fissure
function = motor - extraocular muscle, lateral rectus

Question 17

ORIGIN - cnVII facial
FORAMEN

Answer 17

origin = pontomedullary junction
foramen = through internal acoustic meatus –> out via stylomastoid foramen

Question 18

FUNCTION - cnVII facial

Answer 18

motor - muscles of facial expression
special sensory - taste to ant 2/3 of tongue (chorda tympani)
parasympathetic - lacrimal gland, salivary glands (sublingual and submandibular), nose and palate

Question 19

ORIGIN - cnVIII vestibulocochlear
FORAMEN
FUNCTION

Answer 19

origin = pontomedullary junction
foramen = internal acousic meatus
function = sensory - hearing, cochlear branch, balance = vestibular branch

Question 20

ORIGIN - cnIX glossopharyngeal
FORAMEN

Answer 20

origin = medulla
foramen = jugular foramen

Question 21

FUNCTION - cnIX glossopharyngeal

Answer 21

sensory - post 1/3 tongue (general and special - TASTE), GVA (carotid body), somatic sensory to pharynx above epiglottis
motor - small muscle of pharynx - stylopharyngeus
parasympathetic - salivary gland (parotid)

Question 22

ORIGIN - cnX vagus
FORAMEN

Answer 22

origin = medulla
foramen = jugular foramen

Question 23

FUNCTION - cnX vagus

Answer 23

sensory - larynx ONLY
motor - larynx and pharynx
parasympathetic - cardiac, pulmonary and esophageal plexuses, foregut and midgut

Question 24

ORIGIN - cnXI spinal accessory
FORAMEN
FUNCTION

Answer 24

origin = medulla and spinal cord
foramen = jugular foramen (up through foramen magnum then back via jugular foramen)
function = motor - trapezius and sternocleidomastoid muscles

Question 25

ORIGIN - cnXII hypoglossal
FORAMEN
FUNCTION

Answer 25

origin = medulla
foramen = hypoglossal canal
function = motor - muscles of tongue