Anatomy

Question 1

How many bones make up the orbit?

Answer 1

7

Question 2

Name the bones that make up the orbit…

Answer 2

zygomatic
frontal
sphenoid
ethmoid
maxilla
nasal
lacrimal

Question 3

What part of the orbit is most vulnerable to injury?

Answer 3

orbital floor

Question 4

What bones make up the orbital floor?

Answer 4

maxilla
zygomatic
nasal

Question 5

What are the contents of the superior orbital fissure?

Answer 5

CN III, IV, V1 and VI

Superior ophthalmic vein

Question 6

What cranial nerve passes through the inferior orbital fissure?

Answer 6

CN V2

Question 7

What is the function of muller’s muscle?

Answer 7

assists eyelid elevation

Question 8

What is the nerve supply of mullers muscle?

Answer 8

sympathetic

Question 9

What muscle closes eyelids? and what nerve innervates it?

Answer 9

orbicularis oculi

CN VII

Question 10

Name the syndrome caused by sympathetic injury to mullers muscle?

Answer 10

Horners syndrome

Question 11

Is tear production stimulated by sympathetics or parasympathetics?

Answer 11

parasympathetics

Question 12

What prevents the reflux of tears (lacrimation)?

Answer 12

Valve of Hasner

between inferior meatus and nasolacrimal duct

Question 13

What nerve supplies the conjunctiva?

Answer 13

CN V1

Question 14

Where does the lymph drainage of the conjunctiva go to?

Answer 14

Preauricular and submandibular lymph nodes

Question 15

name the 3 layers of the eye…

Answer 15

Fibrous layer
Vascular layer
Neural layer

Question 16

What makes up the fibrous layer?

Answer 16

sclera and cornea

Question 17

what is the purpose of the sclera?

Answer 17

attachment sites for recti muscles

Question 18

How many layers is the cornea made from?

Answer 18

5

Question 19

What makes up the vascular layer?

Answer 19

choroid
ciliary body
iris

Question 20

What is the function of the choroid?

Answer 20

supplies retina

Question 21

What is the function of the ciliary body?

Answer 21

produces aqueous humour

adjusts of lens

Question 22

What is the function of the iris?

Answer 22

protects retina

Question 23

What makes up the neural layer?

Answer 23

retina

Question 24

What types of cells are in the retina?

Answer 24

rods and cones

Question 25

What is the name of the part of macula with the most rods/cones?

Answer 25

fovea

Question 26

what is the name given to the central part of the retina?

Answer 26

macula

Question 27

What is the anterior chamber of the eye?

Answer 27

in front of lens | contains aqueous humour

Question 28

What is the posterior chamber of the eye?

Answer 28

behind lens

Question 29

What is in the posterior cavity?

Answer 29

vitreous body

Question 30

What muscle increases pupil diameter? and what innervates it?

Answer 30

dilator pupillae | sympathetic

Question 31

What muscle decreases pupil diameter? and what innervates it?

Answer 31

sphincter pupillae | parasympathetic, CN III

Question 32

What is the function of the ciliary muscles?

Answer 32

increase refractive power by constricting ciliary body, relaxing zonules, making lens more spherical

Question 33

Name the 6 extraocular muscles?

Answer 33

``` lateral rectus inferior rectus superior rectus medial rectus superior oblique inferior oblique (4 rectus, 2 oblique) ```

Question 34

What do the recti muscles do?

Answer 34

adduct

Question 35

what do the oblique muscles do?

Answer 35

abduct

Question 36

How does CN III palsy present?

Answer 36

eyes are down and out | dilated pupil

Question 37

How does CN IV palsy present?

Answer 37

restricted eye movement when looking down and in

Question 38

How does CN VI palsy present?

Answer 38

unable to move gaze laterally

Question 39

What nerves give sensory innervation to the eye?

Answer 39

CN II | CN V1

Question 40

What nerves give motor innervation to the eye?

Answer 40

``` CN III, IV, VI (rectus muscles) CN VII (orbicularis oculi) ```

Question 41

What is the principle vascular supply to the eye?

Answer 41

ophthalmic artery

Question 42

What does the central retinal artery supply?

Answer 42

inner 2/3rds of retina

Question 43

What supplies the outer 1/3rd of the retina?

Answer 43

choroidal circulation

Question 44

what is another name for the vascular layer of the eyeball?

Answer 44

uvea

Question 45

What is the origin of the rectus muscles?

Answer 45

common tendinous ring

Question 46

What is the optic disc?

Answer 46

the raised disc on the retina at the point of entry of the optic nerve, lacking visual receptors and so creating a blind spot

Question 47

Which part of the orbit is most susceptible to blow out fractures?

Answer 47

medial wall and orbital floor

Question 48

What is the direction of lacrimal fluid?

Answer 48

``` produced at lacrimal gland washes over eye medially drains through lacrimal puncta into lacrimal sac into nasolacrimal duct ```

Question 49

What does parasympathetic activity on the ciliary body allow for?

Answer 49

thickens lens for near vision

Question 50

what is another name for mullers muscle?

Answer 50

superior tarsus

Question 51

What attaches the superior tarsus to the skin of eyelid?

Answer 51

tendon of levator palpebrae superioris

Question 52

What becomes more "jelly-like" as we age?

Answer 52

vitreous humour

Question 53

What nerve supplies the lateral rectus muscle?

Answer 53

CN VI

Question 54

What nerve supplies the superior oblique muscle?

Answer 54

CN IV

Question 55

What is the pneumonic to remember the cranial nerve innervation of the extraocular muscles?

Answer 55

LR6 SO4 AO3