Lecture 25 - Orbit II

Question 1

What cranial nerves are in the orbit?

Answer 1

CN II, III, IV, V1, and VI

Question 2

What is CN II?

Answer 2

Optic

Question 3

What is CN III?

Answer 3

Oculomotor

Question 4

What is CN IV?

Answer 4

Trochlear

Question 5

What is CN V1?

Answer 5

Opthalmic division of Trigeminal

Question 6

What is CN VI?

Answer 6

Abducens

Question 7

What travels through the optic canal?

Answer 7

Optic nerve, internal opthalmic artery and vein

Question 8

What does CN III innervate?

Answer 8

Ventral oblique
V/M/D recti
Levator palpebrae superioris

Question 9

What does the CN III innervate that is NOT muscle?

Answer 9

Ciliary ganglion

Question 10

What are the branches of CN III?

Answer 10

Long cililary nn., A/P ethmoidal nn., and short ciliary nn.

Question 11

What is the function of the long ciliary nn.?

Answer 11

Sensory from cornea and sclera

Question 12

What is the function of the ethmoidal nn.?

Answer 12

Sensory from nasal cavity

Question 13

What is the function of the short ciliary?

Answer 13

Parasympathetics to pupillary sphincter and ciliary muscle

Question 14

Where do the nerves (not CN III) in the ciliary ganglion come from?

Answer 14

Edinger-westphal nucleus - midbrain

Question 15

Where do the nerves from the ciliary ganglion do?

Answer 15

Pupillary sphincter and ciliary muscles

Question 16

What does the trochlear n. innervate?

Answer 16

Dorsal oblique m.

Question 17

What does the abducens n. innervate?

Answer 17

Lateral rectus m.

Question 18

What are the branches of CN V1 within the orbit?

Answer 18

Nasociliary - Frontal - Lacrimal

Question 19

What does the nasocillary n. do?

Answer 19

Sensory from nasal cavity, cornea and sclera

Question 20

What does the frontal n. do?

Answer 20

Sensory from skin of forehead and scalp

Question 21

What does the lacrimal gland do?

Answer 21

Sensory from lacrimal gland, conjunctiva, and upper eye lid

Question 22

What are the branches off the nasociliary branch of CN V1?

Answer 22

Long ciliary nn and Ethmodial nn.

Question 23

What nerve innervates the lacrimal gland?

Answer 23

postganglionic PNS travel from pterygopalatine ganglion

Question 24

What does the nerve innervating the lacrimal gland travel through?

Answer 24

Orbital fissure

Question 25

What association do PNS nerves have as they enter the head?

Answer 25

Fibers wrap around vasculature

Question 26

What is the internal carotid plexus?

Answer 26

SNS pathway to the eye

Question 27

Where does the internal carotid plexus go?

Answer 27

Dilator pupillae m.

Question 28

What is the main artery that gives rise to external opthalmic a.?

Answer 28

Maxillary

Question 29

What artery gives rise to the internal opthalmic a.?

Answer 29

Internal carotid a.

Question 30

Where is there a connection between the external and internal carotid?

Answer 30

Short ciliary aa. off long ciliary aa.

Question 31

What branches off the short ciliary aa.?

Answer 31

Retinal aa.

Question 32

Where does venous drainage from the orbit go?

Answer 32

Cavernous sinus
– or –
Deep facial vein via V/D external opthalmic v.

Question 33

What muscle adducts the eye?

Answer 33

Medial rectus

Question 34

What muscle abducts the eye?

Answer 34

Lateral rectus

Question 35

What does the dorsal rectus do?

Answer 35

Adduct and elevate eye

Question 36

What does the ventral rectus do?

Answer 36

Adduct and depress eye

Question 37

What does the ventral oblique do?

Answer 37

Abduct and elevate eye

Question 38

What does the dorsal oblique do?

Answer 38

Abduct and depress eye

Question 39

What muscles are involved in looking up?

Answer 39

Dorsal rectus and ventral oblique

Question 40

What muscles are involved in looking down?

Answer 40

Ventral rectus and dorsal oblique