Orbit

Question 1

5 layers of eyelids

Answer 1

1. skin
2. loose CT
3. muscular layer
4. tarsal plate (dense CT, attach to orbital septum)
5. palpebral conjunctiva

Question 2

levator palpebrae superioris

Answer 2

raises upper eyelid, GSE CN III

Question 3

superior tarsal m.

Answer 3

rasises upper eyelid, sympathetic inn.

Question 4

globe: fibrous tunic

Answer 4

cornea and sclera

Question 5

globe: vascular tunic

Answer 5

chooid, ciliary body and muscle, iris

Question 6

shincter pupillae

Answer 6

circular m., PS inn. Constricts pupil (myosis)

Question 7

dilator pupillae

Answer 7

radial m. (curtains), sympathetic inn. Dilates pupil (mydriasis)

Question 8

2 functions of ciliary body

Answer 8

1. produce aqueous humor

2. accomodation

Question 9

flow of aqueous humor

Answer 9

ciliary body > posterior chamber > pupil > anterior chamber > trabecular meshwork > scleral venous sinus (canal of Schlemm)

Question 10

glaucoma

Answer 10

increased aqueous humor > IOP

Question 11

outer layer of optic cup

Answer 11

pigmented epithelial layer of retina

Question 12

inner layer of optic cup

Answer 12

neural layers (rods/cones, bipolar, and ganglion cells) of retina

Question 13

persistent iridopupillary membrane

Answer 13

failure of iridopupillary membrane to degenerate

Question 14

coloboma

Answer 14

failure of choroid fissure to close, usually only affects iris

Question 15

lateral rectus

Answer 15

abduction

Question 16

medial rectus

Answer 16

adduction

Question 17

superior rectus

Answer 17

elevation, adduction, intorsion

Question 18

inferior rectus

Answer 18

depression, adduction, extorsion

Question 19

superior oblique

Answer 19

depression, abduction, intorsion

Question 20

inferior oblique

Answer 20

elevation, abduction, extorsion

Question 21

look straight up

Answer 21

superior rectus, inferior oblique

Question 22

look straight down

Answer 22

inferior rectus, superior oblique

Question 23

test LR

Answer 23

abduct eye

Question 24

test MR

Answer 24

adduct eye

Question 25

test SR

Answer 25

abduct, then elevate eye

Question 26

test IR

Answer 26

abduct, then depress eye

Question 27

test SO

Answer 27

adduct, then depress eye

Question 28

test IO

Answer 28

adduct, then elevate eye

Question 29

CN II

Answer 29

SSA

Question 30

CN III

Answer 30

GSE (levator palpebrae superioris, medial, superior, and inferior rectus, inferior oblique); GVE-P

Question 31

CN IV

Answer 31

GSE (superior oblique)

Question 32

CN V1

Answer 32

GSA

Question 33

CN VI

Answer 33

GSE (lateral rectus)

Question 34

CN VII

Answer 34

SVE (orbicularis occuli)

Question 35

CN III superior division

Answer 35

SR and LPS

Question 36

CN III inferior division

Answer 36

MR, IR, and IO

Question 37

V1 divisions

Answer 37

N- nasociliary
F- frontal
L- lacrimal

Question 38

frontal n. divisions

Answer 38

1. supraorbital n.

2. supratrochlear n.

Question 39

parasympathetic inn. to intraocular eye muscles

Answer 39

pregang. cell bodies: Edinger-Westphal nucleus in midbrain
pregang. fibers: CN III
postgang. cell bodies: ciliary ganglion
postgang. fibers: short ciliary nn.

constrict pupils (myosis) and accomodation

Question 40

sympathetic inn. to superior tarsal and dilator pupillae

Answer 40

pregang. cell bodies: T1-2 lateral horn
pregang. fibers: sympathetic chain
postgang. cell bodies: superior cervical ganglion
postgang. fibers: internal carotid n. > brs. of V1

dilate pupils (mydriasis) and elevate upper eyelid

Question 41

pupillary light reflex

Answer 41

b/l constriction of pupils. In by II, out by III

Question 42

corneal reflex

Answer 42

b/l closure of eyelids. In by V1, out by VII

Question 43

accommodation

Answer 43

looking from distant to near object. Ciliary mm. contract, pupils constrict, eyes adduct. In by II, out by III