Orbit

Question 1

Thickened funnel shaped fascial layer that lines the orbit

Answer 1

periorbita

Question 2

What are the thinnest walls of the orbit?

Answer 2

The medial and lateral walls

Question 3

Flow of tears

Answer 3

Lacrimal gland–> conjunctival sac–> lacrimal punctum–> nasolacrimal duct–>nasal cavity

Question 4

Purpose of tarsal gland

Answer 4

secrete a fatty substance to prevent lids from sticking together when closed

Question 5

What anchors the tarsal plates?

Answer 5

Medial and lateral palpebral ligaments

Question 6

Function of levator palpebrae superioris

Answer 6

skeletal muscle that raises the eyelid. It can fatigue.

Question 7

What is the superior tarsal muscle

Answer 7

A smooth muscle that is responsible for the tone of the eyelid

Question 8

What innervates the superior tarsal muscle

Answer 8

Sympathetic fibers that travel with the frontal nerve

Question 9

What can cause horner’s syndrome?

Answer 9

Lesion of superior cervical ganglion.

Question 10

What is Horner’s syndrome

Answer 10

causes the tone of the upper eyelid to relax since superior tarsal is innervated by sympathetic fibers

Question 11

What muscle abducts the eye

Answer 11

Lateral rectus

Question 12

What muscle adducts the eye

Answer 12

medial rectus

Question 13

What muscles elevate the eye

Answer 13

superior rectus, inferior oblique

Question 14

What muscles depress the eye

Answer 14

Inferior rectus, superior oblique

Question 15

What muscle intorts the eye

Answer 15

Superior oblique

Question 16

What muscle extorts the eye

Answer 16

inferior oblique

Question 17

Test lateral rectus

Answer 17

Abduct the eye

Question 18

Test medial rectus

Answer 18

adduct the eye

Question 19

Test superior rectus

Answer 19

abduct eye to the line of pull and look up

Question 20

Test inferior rectus

Answer 20

abduct eye to the line of pull and look down

Question 21

Test superior oblique

Answer 21

adduct the eye and look down

Question 22

Test inferior oblique

Answer 22

adduct and look up

Question 23

diplopia

Answer 23

double vision

Question 24

What would cause diplopia

Answer 24

A cranial nerve IV-trochlear lesion because the inferior oblique is unopposed

Question 25

3 layers of the eyeball

Answer 25

Fibrous layer, vascular layer, retinal layer

Question 26

What composes the fibrous layer

Answer 26

cornea and sclera

Question 27

What composes the vascular layer

Answer 27

choroid, ciliary body, iris

Question 28

What composes the retinal layer

Answer 28

bipolar neurons, optic disc, macula lutea

Question 29

What is the optic disc

Answer 29

Where the optic nerve enters the eye and it's fibers spread out. There are no receptors here so this is the blind spot

Question 30

Macula lutea

Answer 30

area lateral to the optic disc where there is the fovea centralis

Question 31

Describe the cornea

Answer 31

transparent and avascular

Question 32

Aqueous humor

Answer 32

a clear watery fluid in the anterior and posterior chambers of the eyeball.

Question 33

What produces the aqueous humor

Answer 33

The ciliary processes

Question 34

Describe flow of aqueous humor

Answer 34

Produced by ciliary processes that passes from the posterior chamber into the anterior chamber via the pupil. It is drained away through spaces at the filtration angle into a venous canal of Schlemm

Question 35

What can cause glaucoma

Answer 35

Blockage of aqueous humor drainage

Question 36

Purpose of aqueous humor

Answer 36

nutrients for avascular cornea and lens

Question 37

What is the purpose of the suspensory ligament of the lens

Answer 37

Contraction and relaxation controls the curvature of the lens

Question 38

What innervates the muscles responsible for eye accommodation

Answer 38

CN III

Question 39

How does eye accommodation work?

Answer 39

Idk. Look at notes.

Question 40

What process would be lost if CN III is damaged

Answer 40

Loss of accommodation/focus.

Question 41

Cataracts

Answer 41

Loss of transparency of the lens

Question 42

Vitreous body

Answer 42

jelly like matrix with a fine meshwork of collagen fibers that fills the vitreous chamber of the eyeball.

Question 43

What it the ophthalmic artery a branch of?

Answer 43

The internal carotid artery

Question 44

How does the ophthalmic artery enter the orbit and what is its relationship to the optic nerve

Answer 44

it enters via the optic canal and travels superior to the optic nerve

Question 45

Branches of the ophthalmic artery

Answer 45

Lacrimal artery, central artery of retina, ciliary arteries, supraorbital artery, anterior and posterior ethmoidal arteries, dorsal nasal arteries, and supratrochlear artery

Question 46

What does the infraorbital artery branch from and what does it supply

Answer 46

The maxillary artery and it supplies structures of the orbital floor

Question 47

Central vein of the retina

Answer 47

Travels with the central artery of the retina to drain to the cavernous sinus

Question 48

Flow of venous drainage from superior and inferior ophthalmic veins

Answer 48

They originate on the anterior aspect of the orbit from supraorbital and angular veins. They exit the orbit via the superior orbital fissure and enter the cavernous sinus.

Question 49

Branches of V1

Answer 49

Nasociliary, Facial, Lacrimal

Question 50

Frontal nerve

Answer 50

Branches into supraorbital and supratrochlear nerves that innervate the forehead and anterior region of the scalp

Question 51

Lacrimal nerve

Answer 51

passes to the lacrimal gland and provides sensory innervation to the lacrimal gland, conjunctiva of eye, and sensory over the upper eyelid.

Question 52

Nasociliary nerves

Answer 52

communicates with the ciliary ganglion. Branches into anterior and posterior ethmoidal air cells to innervate them in the nasal cavity and external aspect of the nose

Question 53

What do sympathetics hitchhike on to get to the dilator pupillae

Answer 53

(LSD) long ciliary nerves

Question 54

Long ciliary nerves

Answer 54

run in the choroid plexus to provide sensory innervation to iris and cornea.

Question 55

Where do short ciliary nerves originate?

Answer 55

Ciliary ganglion.

Question 56

What do postganglionic parasympathetic fibers from the ciliary ganglion traveling on the short ciliary nerve go to?

Answer 56

The sphincter papillae and the ciliaris muscle

Question 57

What nerve fibers travel through the ciliary ganglion without synapsing?

Answer 57

Sensory fiberis for the eye

Question 58

STUDY PARASYMPATHETIC INNERVATION OF THE LACRIMAL GLAND

Answer 58

STUDY PARASYMPATHETIC INNERVATION OF THE LACRIMAL GLAND