Infratemporal Fossa/ Orbit and Ear

Question 1

Why is the angular vein important?

Answer 1

Drains into the cavernous sinus, and could cause infection in the head.

Question 2

What are the mm of mastication, and what do they do?

Answer 2

1. medial pterygoid- closes mandible, assists in grinding motions
2. lateral pterygoid- slight medial movement for grinding, protrudes mandible.
3. masseter- closes and slightly retrudes mandible
4. temporalis- closes and retrudes the mandible

Question 3

What do the long ciliary nerves do?

Answer 3

They are sensory to the eyeball, as well as carrying sympathetics from superior cervical ganglion to pupil dilator mm.

Question 4

What is the artery that runs lateral to the eye, branching off of the opthalmic artery?

Answer 4

The lacrimal artery, going to the lacrimal gland.

Question 5

Spread of infection:
Superior and inferior ophthalmic veins drain where, and in what plane? These two veins communicate with which others anteriorly?
The pterygoid plexus drains into what other plexus?
The basilar plexus drains into what?

Answer 5

Into the pterygoid plexus and cavernous sinus posteriorly.
Anteriorly, they communicate with the facial and supraorbital veins.
Pterygoid plexus drains into basilar plexus.
Basilar plexus drains into interval vertebral plexus, in the epidural space.

Question 6

Corneal reflex: sensory and motor?

Answer 6

sensory: CN V1
Motor: CN VII
If i poke you in the eyeball, you’ll close your eye.

Question 7

Pupillary reflex: sensory and motor?

Answer 7

sensory: CN II
Motor: CN III
shine light in your eye, your pupil constricts

Question 8

blink reflex :sensory and motor?

Answer 8

Sensory: CN II, or CN VIII
Motor: CN VII
scare you, you blink

Question 9

semicircular canals are for?

Answer 9

dynamic balance (acceleration)

Question 10

The Utricles are for?

Answer 10

static balance.

Question 11

Cone of light in the right ear should be at?
Left ear?
What would distortion indicate?

Answer 11

5 o’clock
7 o’clock
Distortion indicates increased inner ear pressure, or otitis media.

Question 12

The tensor tympani is above what? What innervates it?

Answer 12

It is above the auditory tube on the way to the tympanic membrane. It is innervated by CN V3

Question 13

Sensation to the anterior aspect of the external ear?

Answer 13

CN V3- articulotemporal n.

Question 14

What innervates the external ear canal?

Answer 14

CN X

Question 15

What innervates the external ear?

Answer 15

C2 and C3 from the cervical plexus

Question 16

Sensation to the middle ear?

Answer 16

CN IX

Question 17

Sneeze, gag, and cough reflexes?

Answer 17

Sensory: 
sneeze- CN V2
gag- CN IX
cough- CN X
Motor:
All are CN X

Question 18

If trochlear nerve is damaged, which way does the head tilt?

Answer 18

To the opposite side of the injury

Question 19

Sign of a cavernous sinus thrombus?

Answer 19

Eye looks medially, since the abducens nerve can’t make the eye look laterally.

Question 20

Sign of occulomotor nerve damage?

Answer 20

Present with eye down and out, and ptosis. Possible loss of pupillary light reflex.

Question 21

which nerve runs next to/onto C1 of the cervical plexus?

Answer 21

CN XII