Cranial Vault, Orbit, Ear

Question 1

Diploe

Answer 1

two outer compact layers and spongey layer between

Question 2

What bones are contained w/i the anterior cranial fossa?

Answer 2

frontal; ethmoid; sphenoid

Question 3

What bones are contained w/i the middle cranial fossa?

Answer 3

sphenoid; temporal

Question 4

What bones are contained w/i the posterior cranial fossa?

Answer 4

temporal; occipital

Question 5

What are the 2 unique features of the anterior fossa?

Answer 5

crista gali (of ethmoid) - dura attach to it
cribiform plate: where olfactory nerves send axons through

Question 6

What is clinically significant about the cribiform plate/olfactory nerve relationship?

Answer 6

When the frontal bone is fractures (head hits dashboard), the axons in th cribiform plate can be severed and person can become anosmic (can’t smell)

Question 7

What goes through the optic canal?

Answer 7

CN II and opthalmic a.

Question 8

What goes through sup. orb fissure?

Answer 8

CN III, IV, VI, V1 and opthalmic veins

Question 9

While nothing courses all the way through foramen lacerum, what enters it through the side and comes out the top?

Answer 9

internal carotid

Question 10

What lies on either side of the optic chiasm?

Answer 10

trigeminal (semilunar) ganglia and cavernous sinus

Question 11

What artery lies in the groove coming off of the foramen spinosum?

Answer 11

middle meningeal a.

Question 12

What goes through the hypoglossal canal?

Answer 12

CN XII

Question 13

What travels through the internal acoustic meatus?

Answer 13

CN VII and VIII

Question 14

What goes through the jugular foramen?

Answer 14

internal jugular; CN IX, X, XI

Question 15

kluver-bucy syndrome

Answer 15

amygdala destruction (rapid deceleration damaging temporal lobes) causes it; behavioral changes; inability to suppress desire to explore environment in sexual way

Question 16

What are the tell tale signs of basilar skull fractures?

Answer 16

Battle’s sign: mastoid ecchymosis (bruising) and hemotympanum (blood in inner ear)

Question 17

What produces CSF and where?

Answer 17

choroid plexus - in the ventricles

Question 18

Where does CSF go to drain?

Answer 18

CSF crosses arachnoid granulations to enter sinuses to drain along with venous blood from brain

Question 19

Meningioma

Answer 19

tumors of meninges; benign however could be inoperable if not in a place able to be reached

Question 20

subdural hematoma

Answer 20

When the dura splits (in places other than sinuses)

Question 21

Which type of brain bleed will produce blood in spinal tap?

Answer 21

subarachnoid (not epidural or subdural)

Question 22

What separates the cerebellum from the occipital lobes of cerebral cortex?

Answer 22

tentorium

Question 23

Which type of brain bleed is mostly venous?

Answer 23

subdural

Question 24

What kind of bleed are assoicated w/ skull fractures?

Answer 24

epidural (arterial) = smaller winder to fix it - 2 hrs

Question 25

If you have a migraine, what artery is likely to be the cause?

Answer 25

middle meningeal

Question 26

What is the first branch off of the internal carotid a. ?

Answer 26

opthalmic a.

Question 27

What structures are found within the cavernous sinus along with the internal carotid?

Answer 27

CN V2, V3, CN III, CN IV, CN VI

Question 28

If there is an infection spread into the cavernous sinus (say from picking zits) which nerve would be affected?

Answer 28

CN VI - others are within the wall of the sinus

Question 29

CN VI lesion/infection

Answer 29

causes medial deviation of eye b/c innervates lateral rectus

Question 30

Berry aneurysms

Answer 30

can occur anywhere on circle of willis - most don't know they have them; if ruptured, about 50% will die If found before rupture, can clip or coil

Question 31

conjunctivitis

Answer 31

infection of the outermost epithelium of eye (conjunctiva); allergy (bilateral), bacterial or viral; 90% is viral - bacterial is harder to transmit but more serious

Question 32

Where do syes occur?

Answer 32

gland openings of the eye lashes

Question 33

Where do tears drain to?

Answer 33

the lacrimal puncta

Question 34

When everting the eye lid and you can see light stripes, what are those?

Answer 34

meibomian glands

Question 35

What gives sensory innervation to and around the eye?

Answer 35

CN V: V1 and V2 branches

Question 36

When you have pain from sinusitis, what nerve is the cause?

Answer 36

nasociliary n.

Question 37

Does the lacrimal branch of V1 innervate the lacrimal gland?

Answer 37

NO b/c it's sensory lacrimal gland is inn. by CN VII

Question 38

What nerve arise from the pontomedullary junction?

Answer 38

CN VII (Facial)

Question 39

What nerve innervates the lacrimal gland and salivary glands?

Answer 39

CN VII

Question 40

What nerve is affected by bells palsy?

Answer 40

CN VII; dry eyes and dry mouth

Question 41

Cornea

Answer 41

responsible for 90% of refraction of the eye; avascular

Question 42

what provides innervatinon to the cornea?

Answer 42

CN V

Question 43

What nerves are involved in the corneal reflex?

Answer 43

CN V, III, VII - sensory, close and open

Question 44

dilator muscles of the eye are innervated by ?

Answer 44

sympathetics

Question 45

sphincter muscles of the eye are innervated by?

Answer 45

parasympathetics

Question 46

What structure in the eye allows for drainage of aqueous humor?

Answer 46

Schlemm's canal; if blocked = glaucoma

Question 47

Which humor of the eye do we make consistently, and which is the same amout we are born with?

Answer 47

aquesous humor - constantly being made vitreous humor - all we will have

Question 48

What structure of the eye is effected in a cataract?

Answer 48

lens

Question 49

Where is the blind spot in the eye?

Answer 49

where the optic disc is located, because only nerve fibers there

Question 50

Describe what you see when looking at a pt pupul?

Answer 50

medially will see the optic disc/nerve; more laterally you will see the darker spot called macula densa - high density of cones meaning high visual acuity; would be able to see intracranial pressure at optic disc

Question 51

If the optic nerve is completely cut, what is the result?

Answer 51

monocular blindness (blindness in one eye)

Question 52

if the right optic tract is cut, what is the result?

Answer 52

homonymoushemianopia (blindness in left half of each eye)

Question 53

If the optic chiasm is cut down the middle, what is the result?

Answer 53

bitemporal hemianopia (blindness in both temporal sides)

Question 54

LR6SO4AO3

Answer 54

lateral rectus inn: CN VI sup. oblique inn: CN IV all other eye muscle inn: CN III

Question 55

How do you test the function of SO4?

Answer 55

have the patient look down and in. this uses inferior rectus, medial rectus and sup. oblieuq to stablize/smooth it

Question 56

How does a CN IV iss present?

Answer 56

blurry vision with reading and trouble going down stairs

Question 57

what is the condition called when eyes are not lined up perfectly?

Answer 57

strabismus

Question 58

blepheritis

Answer 58

infection of eyelid

Question 59

What artery supplies the orbit, retina and also communicates with the external carotid?

Answer 59

opthalmic a.

Question 60

Due to the lack of supQ tissue in the pinna, what will result if hematomas aren't drained?

Answer 60

cauliflower ear

Question 61

where are the neurons for the ear found and what kind are they?

Answer 61

spiral ganglion in cochlear portion - bipolar neurons

Question 62

what part of the ear is related to balance?

Answer 62

vestibular portion (has liquid)

Question 63

What affect does infection or blood have on examining the eary

Answer 63

the cone of light, which is normally seen in the tympanic membrane will not be visible