The Orbit and Eye

Question 1

palpebral conjunctiva

Answer 1

membrane lining inner lid

Question 2

bulbar conjunctiva

Answer 2

membrane lining surface of eye

Question 3

cunjunctival sac

Answer 3

potential space between palpebral and bulbar conjunctiva

Question 4

fornices

Answer 4

conjunctival reflections from eyelid to eye

Question 5

tarsal glands

Answer 5

embedded in tarsal plates

are modified sebaceous glands that increase viscosity of tears

Question 6

ciliary glands

Answer 6

associated with eyelash follicles

Question 7

orbital septum

Answer 7

extensions of periosteum into upper and lower lids

Question 8

how many bones is the bony orbit made of?

Answer 8

7

Question 9

contents of optic canal

Answer 9

CN II and opthalmic a

Question 10

contents of superior orbital fissure

Answer 10

CN III, IV, V1, VI and opthalmic vv (from ICA)

Question 11

contents of supraorbital foramen

Answer 11

supraorbital n (br of V1) and a

Question 12

contents of inferior orbital fissure

Answer 12

infraorbital n, zygomatic n and a

Question 13

contents of infraorbital foramen

Answer 13

infraorbital n (V2) and a

Question 14

contents of anterior ethmoid foramen

Answer 14

anterior ethmoidal n (br of V1) and a

Question 15

contents of posterior ethmoidal foramen

Answer 15

posterior ethmoidal n (V1) and a

Question 16

three layers of eyeball

Answer 16

1. fibrous (outer/external)
2. vascular (middle)
3. inner (internal)

Question 17

where do extrinsic eye mm attach?

Answer 17

sclera

Question 18

structures in middle eye

Answer 18

1. choroid
2. ciliary body
3. iris
4. pupil
5. vorticose vv

Question 19

choroid

Answer 19

thin middle layer of ciliary aa and vorticose vv

Question 20

ciliary body

Answer 20

smooth m around lens for accomodation

Question 21

iris

Answer 21

controls pupil size

dilator pupilae: radial, sympathetic
sphincter: circular, psymp

Question 22

pupil

Answer 22

light enters

Question 23

vorticose vv

Answer 23

drain choroid from each posterior quadrant into sup and inf opthalmic vv

Question 24

structures in inner eye

Answer 24

1. retina
2. macula lutea
3. fovea centralis
4. optic disc

Question 25

retina

Answer 25

neural layer receiving light rays (rods and cones)

Question 26

macula lutea

Answer 26

oval part of retina for visual acuity (only cones)

Question 27

fovea centralis

Answer 27

most acute vision, at center of macula

Question 28

optic disc

Answer 28

CN II and retinal vessels enter/exit here (blind spot)

Question 29

refractive media of eye

Answer 29

1. cornea: refracts light
2. lens: focuses light and near or distant objects on retina
3. aqueous humor: watery filling ant to lens
4. vitreous humor: jelly filling post to lens

Question 30

drainage of tears

Answer 30

lacrimal gland, lacrimal canaliculi, lacrimal sac, nasolacrimal duct

Question 31

visual fields

Answer 31

1. nasal retina: remains ipsilateral

2. temporal retina: crosses over at chiasm

Question 32

optic n lesion

Answer 32

total blindness in affected eye

Question 33

optic chiasm lesion

Answer 33

loss of peripheral vision

Question 34

optic tract lesion

Answer 34

ipsilateral nasal VF loss and contralateral temporal VF loss

Question 35

what CNs does pupillary light reflex test?

Answer 35

CN II and III

Question 36

arteries of orbit and eye

Answer 36

1. opthalmic a: gives rise to all others
2. post ciliary aa: outer and middle layers of eye
3. central retinal a: inner layer of retina
4. ethmoidal aa: ant cranial fossa, nose, and sinuses
5. supraorbital a: central forehead
6. supratrochlear a: medial forehead
7. lacrimal gland

Question 37

extrinsic eye mm and movements

Answer 37

1. superior rectus: elevate and adduct
2. levator palpebrae superioris: raise upper lid
3. sup oblique: depress and ABduct
4. medial rectus: adducts
5. inf oblique: elevate and ABduct
6. inf rectus: depress and adduct
7. lat rectus: ABduct

Question 38

innervation of extrinsic eye mm

Answer 38

LR: 6
SO: 4
R: 3