Eye & Ear

Question 1

What is the lacrimal gland?

Answer 1

• secretes the fluid & collected in the lacrimal canaliculi to the sac
• located sup. laterally
• passes into inf. nasal meatus through nasal lacrimal duct

Question 2

What are the bones of the orbit?

Answer 2

• frontal
• sphenoid
• zygomatic
• maxillary
• lacrimal
• ethmoid

Question 3

What is the levator palpabrae superioris in the eye and what is it innervated by?

Answer 3

• opens the eye
• inn: oculomotor (CN 3)

Question 4

What are the external structures of the eye?

Answer 4

• sclera = white part
• cornea = transparent part; covers iris & pupil
• conjunctiva = int lining of eyelid; covers sclera

Question 5

What are the internal structures of the eye?

Answer 5

• choroid = middle eye
• retina= inner eye layer
• fovea (macula)= area of greatest visual acuity
• optic disk= blind spot

Question 6

What is the anterior aspect of the eye?

Answer 6

• covered by orbicularis oculi
• nerves: supraorbital, supranochlear, & infraorbital
• contains trochlea

Question 7

What is the posterior aspect of the eye?

Answer 7

• levator palpabrae sup.
• sup. rectus
• sup. oblique running through cochlea
• med & lat rectus

Question 8

What are the nerves of the eye?

Answer 8

• optic (CN 2)-> sensory
• oculomotor (CN 3) -> sup division to sup rectus & lev palpa sup; inf division to medial rectus, inf rectus, & inf oblique
• trochlear (CN 4) -> sup oblique
• abducent (CN 6) -> lat rectus

Question 9

What do the short & long ciliary nerves carry?

Answer 9

• short: carry sympathetic & para to ciliary body & iris
• long: carry sympathetic to dilator pupillae & sensory from cornea + iris

Question 10

What is the action & innervation of the levator palpabrae superiorris (LPS) in the eye?

Answer 10

• action: elevation of sup. eyelid
• inn: oculomotor (CN 3)

Question 11

What is the action & innervation of the superior oblique in the eye?

Answer 11

• action: abducts & depress
• inn: trochlear (CN 4)

Question 12

What is the action & innervation of the inferior oblique in the eye?

Answer 12

• action: adbuction & elevation
• inn: oculomotor (CN 3)

Question 13

What is the action & innervation of the superior rectus in the eye?

Answer 13

• action: adduction & elevation
• inn: oculomotor (CN 3)

Question 14

What is the action & innervation of the inferior rectus in the eye?

Answer 14

• action: adduction & depression
• inn: oculomotor (CN 3)

Question 15

What is the action & innervation of the medial rectus in the eye?

Answer 15

• action: adduction
• inn: oculomotor

Question 16

The oculomotor nerve innervates what eye muscles?

Answer 16

all EXCEPT sup oblique

Question 17

What is the vascular supply of the eye?

Answer 17

• opthalmic -> superatrochlea, dorsal nasal, supra-orbital
• lacrimal -> ant & post ciliary

Question 18

What are 3 structures of the ear?

Answer 18

• ext
• middle
• inner

Question 19

What are the structures of the middle ear?

Answer 19

• tympanic membrane = ear drum -> has pars flaccida & pars tensa
• malleus, incus, & stapes
• eustachian tube= connects middle ear to pharynx to relieve pressure

Question 20

What are the 3 parts of the malleus, incus, & stapes in the ear?

Answer 20

• oval window: receive vibrations from stapes
• round window: stop vibrations from rebounding
• tensor tympani: reduces/dampens vibration

Question 21

What are the 2 major divisions of the vestibulocochlear nerve (CN 8)?

Answer 21

• vestibular: for balance, gaze, & acceleration
• cochlear: for hearing

Question 22

What are the structures of the inner ear?

Answer 22

• bony labyrinth & membranous
• cochlea
• semicircular canals = motion & rotational sense

Question 23

What does the faical nerve (CN 2) branch into & what does it travel through?

Answer 23

• branches into chorda tympani
• travels through tympanic membrane