Anatomy (Eye And Orbit)

Front 1

what bones form the margin of the orbit?

Back 1

frontal bone
zygomatic bone
maxillary bone

Front 2

what bones form the medial wall of the orbit?

Back 2

lacrimal bone
ethmoid bone

Front 3

what bones form the lateral wall of the orbit?

Back 3

zygomatic bone

Front 4

what bones form the floor of the orbit?

Back 4

maxillary bone

Front 5

what bones form the roof of the orbit?

Back 5

orbital plate of the frontal bone

Front 6

what forms the deep wall of the orbit?

Back 6

greater and lesser wings of the sphenoid bone

Front 7

where is the superior orbital fissure?

Back 7

between the greater wing and lesser wing of the sphenoid bone

Front 8

where is the inferior orbital fissure?

Back 8

between the maxillary bone and the greater wing of the sphenoid bone

Front 9

where does the optic canal lie?

Back 9

in the root of the lesser wing of the sphenoid bone

Front 10

how do the medial walls of the orbit relate to one another? the lateral walls?

Back 10

medial walls are parallel

lateral walls diverge

Front 11

what forms the fibromuscular cone around the eyeball?

Back 11

continuous fascial sheath around and between the muscles of the eye

Front 12

what fills the interior of the fibromuscular cone of the eye?

Back 12

fat

Front 13

where is the levator palpebrae superioris?

Back 13

superior to the cone of the eye, below the roof of the orbit

Front 14

what are the attachments of the levator palpebrae superioris?

Back 14

from back of orbit
to upper eyelid

Front 15

what supplies innervation to the levator palpebrae superioris?

Back 15

CN III
sympathetic nerves

Front 16

what is the result of a lesion of one of the nerves supplying the levator palpebrae superioris?

Back 16

ptosis

Front 17

what is ptosis?

Back 17

drooping of the eyelid

Front 18

what is the purpose of the lacrimal fluid?

Back 18

moistens and lubricates the conjunctiva and cornea

provides nutrients and dissolved oxygen to the cornea

Front 19

what conveys lacrimal fluid from the lacrimal gland to the lacrimal sac?

Back 19

lacrimal ducts

Front 20

what are lacrimal canaliculi?

Back 20

tubes that drain the lacrimal fluid to the lacrimal sac, starting from the punctum

Front 21

what is a punctum?

Back 21

minute orifice through which the lacrimal canaliculi open onto the interior surface of the eyelid

Front 22

what drains lacrimal fluid from the lacrimal sac?

Back 22

nasolacrimal duct

Front 23

where does the nasolacrimal duct go?

Back 23

from the nasolacrimal sac to the inferior nasal meatus (back of nose and throat)

Front 24

how are parasympathetic secretomotor fibers carried to the lacrimal gland?

Back 24

facial nerve (pre) -> greater petrosal nerve (pre) -> nerve to pterygoid canal (pre) -> pterygopalatine ganglion (syn) -> zygomatic n. (post) -> lacrimal n. (post) -> lacrimal gland

pre=preganglionic
syn=synapse
post=postganglionic

Front 25

from what nerve is the zygomatic nerve a branch?

Back 25

maxillary division of the trigeminal nerve (V2)

Front 26

from what nerve is the lacrimal nerve a branch?

Back 26

ophthalmic division of the trigeminal nerve (V1)

Front 27

what is the function of the lateral rectus muscle?

Back 27

abductor of the eye (turns pupil laterally)

Front 28

what is the function of the medial rectus muscle?

Back 28

unilaterally - adductor of the eye (turns pupil medially)

bilaterally - convergence of gaze (focuses eyes on nearby object)

Front 29

what is the function of the superior rectus muscle?

Back 29

turns the pupil superiorly and medially

Front 30

what is the function of the inferior rectus muscle?

Back 30

turns the pupil inferiorly and medially

Front 31

where does the superior oblique muscle of the eye run?

Back 31

along medial wall to reach trochlea, looping posteriorly through a fascial sling before being attached to the the eyeball (deep to superior rectus muscle)

Front 32

what is the function of the superior oblique muscle of the eye?

Back 32

incyclotorsion (primary)
depression (secondary)
abduction (tertiary)

Front 33

where does the inferior oblique muscle of the eye run?

Back 33

from floor of orbit laterally below the eyeball, attaching to the eyeball laterally

Front 34

what are the functions of the inferior oblique muscle of the eye?

Back 34

excyclotorsion (primary)
elevation (secondary)
abduction (tertiary)

Front 35

what muscles are required to look straight up?

Back 35

superior rectus
inferior oblique

Front 36

what muscles are required to look straight down?

Back 36

inferior rectus
superior oblique

Front 37

what muscles are required to look to the left?

Back 37

left lateral rectus
right medial rectus

Front 38

from what artery does the ophthalmic artery arise?

Back 38

internal carotid artery

Front 39

from what artery does the central artery of the retina arise?

Back 39

ophthalmic artery

Front 40

where does the central artery of the retina travel?

Back 40

enters the optic nerve, travels near its center to the eyeball, and after going into the eyeball, divides into nasal and temporal branches (with corresponding veins)

Front 41

what are the arteries which can be seen with an ophthalmoscope?

Back 41

nasal and temporal branches of the central artery of the retina

Front 42

what are the two end branches of the ophthalmic artery?

Back 42

dorsal nasal artery
supratrochlear artery

Front 43

what are the branches of the ophthalmic artery?

Back 43

central retinal artery
lacrimal artery
posterior ciliary arteries
supraorbital artery
posterior ethmoidal artery
anterior ethmoidal artery
medial palpebral artery
dorsal nasal artery
supratrochlear (frontal) artery

Front 44

where does the lacrimal artery run?

Back 44

along the lateral wall of the orbit

Front 45

what is supplied by the lacrimal artery?

Back 45

lacrimal gland
eyelids

Front 46

how many long posterior ciliary arteries branch from the ophthalmic artery?

Back 46

2

Front 47

how many short posterior ciliary arteries branch from the ophthalmic artery?

Back 47

many

Front 48

what is supplied by the posterior ciliary arteries?

Back 48

choroid inside the eyeball
short - back of eyeball
long - corneoscleral junction

Front 49

where do long posterior ciliary arteries break up into branches?

Back 49

corneoscleral junction

Front 50

from what arteries do the anterior ciliary arteries branch?

Back 50

lacrimal artery and/or posterior ciliary arteries (long or short)

Front 51

what is supplied by the anterior ciliary arteries?

Back 51

choroid in the front of the eyeball

Front 52

what is supplied by the supraorbital artery?

Back 52

scalp

Front 53

what is supplied by the anterior and posterior ethmoidal arteries?

Back 53

ethmoidal air cells
upper part of nasal mucosa (posterior only)

Front 54

what branch from the ophthalmic artery continues into the nasal cavity?

Back 54

posterior ethmoidal artery

Front 55

into what do the veins of the orbit drain?

Back 55

superior ophthalmic vein
inferior ophthalmic vein

Front 56

with what do the superior and inferior ophthalmic veins communicate?

Back 56

cavernous sinus
pterygoid plexus of veins

Front 57

what is an ethmoidal air cell?

Back 57

paranasal sinus

Front 58

where does CN IV enter the orbit?

Back 58

above the fibrous ring (outside of muscular cone)

Front 59

where does CN IV enter the superior oblique?

Back 59

the upper border of the superior oblique

Front 60

where does CN VI go immediately after entering the orbit?

Back 60

enters within the muscular cone and immediately turns lateral to enter the lateral rectus

Front 61

where are the two branches of CN III within the orbit?

Back 61

above and below the nasociliary nerve within the muscular cone

Front 62

what is innervated by the superior branch of CN III?

Back 62

rectus superioris
levator palpebrae superioris

Front 63

what is innervated by the inferior branch of CN III?

Back 63

rectus medialis
rectus inferioris
obliquus inferioris

Front 64

what nerve carries preganglionic parasympathetic fibers, which are destined for the eyeball?

Back 64

oculomotor branch to inferior oblique muscle

Front 65

from where do the preganglionic parasympathetic fibers for the eyeballs arise?

Back 65

Edinger-Westphal nucleus in the midbrain

Front 66

where do parasympathetic fibers for the eyeball synapse?

Back 66

ciliary ganglion

Front 67

what carries postganglionic parasympathetic fibers to the back of the eyeball?

Back 67

short ciliary nerves

Front 68

what is supplied by the postganglionic parasympathetic fibers of the short ciliary nerves?

Back 68

ciliaris muscle
sphincter papillae

Front 69

from where do all sensory nerves of the orbit branch?

Back 69

ophthalmic division of the trigeminal nerve (V1)

Front 70

what are the branches of CN V in the orbit?

Back 70

frontal nerve
lacrimal nerve
nasociliary nerve

Front 71

where do the branches from CN V enter the orbit?

Back 71

frontal nerve - above fibrous ring
lacrimal nerve - above fibrous ring
nasociliary nerve - within fibrous ring

Front 72

on what does the frontal nerve lie?

Back 72

directly below the roof of the orbit, the frontal nerve lies on the levator palpebrae superioris

Front 73

what are the branches of the frontal nerve?

Back 73

supraorbital nerve
supratrochlear nerve

Front 74

what is supplied by the supraorbital nerve?

Back 74

scalp

Front 75

what is supplied by the supratrochlear nerve?

Back 75

scalp

Front 76

what is innervated by the lacrimal nerve?

Back 76

sensory to skin of eyelids
postganglionic parasympathetic secretomotor fibers to lacrimal gland

Front 77

to what artery is the nasociliary nerve's course similar? in what ways is it different?

Back 77

ophthalmic artery

short ciliary nerves from ciliary ganglion, not nasociliary nerve
lacrimal nerve is a separate branch from ophthalmic division

Front 78

what nerve gives rise to the two long ciliary nerves entering the back of the eyeball?

Back 78

nasociliary nerve

Front 79

what type of fibers are carried by the long ciliary nerves?

Back 79

postganglionic sympathetic fibers for dilator pupillae

sensory fibers for cornea

Front 80

what is supplied by the sympathetic fibers of the long ciliary nerves?

Back 80

dilator pupillae
cornea

Front 81

from where do the postganglionic sympathetic fibers of the long ciliary nerves arise?

Back 81

superior cervical ganglion

Front 82

from which nerve is the posterior ethmoidal nerve a branch?

Back 82

nasociliary nerve

Front 83

from which nerve is the anterior ethmoidal nerve a branch?

Back 83

nasociliary nerve

Front 84

what are the two terminal branches of the nasociliary nerve?

Back 84

anterior ethmoidal nerve
infratrochlear nerve