Orbital cavity and lacrimation

Question 1

Lateral borders of orbital cavity

Answer 1

Zygomatic and sphenoid

Question 2

Orbital cavity floor

Answer 2

Sphenoid, palatine and maxillary bones

Question 3

Orbital cavity roof

Answer 3

Frontal bone

Question 4

Orbital cavity medial border

Answer 4

Sphenoid, ethmoid, lacrimal and maxillary

Question 5

Difference between orbit of eye and orbit of axis

Answer 5

Orbit is anterolateral but optic axis looks straight ahead

Question 6

Innervation and function of orbiculares oculi

Answer 6

Facial nerve and closes eyelids

Question 7

Innervation and function of elevator palpebre superiors

Answer 7

Oculomotor and opens eyelids

Question 8

Which muscle opens eye

Answer 8

Muller’s muscle

Question 9

Tarsal’s glands

Answer 9

sebaceous glands posterior to eyelashes - oily secretions limit overflow of tears

Question 10

Ptosis causes

Answer 10

Ptosis occurs when sympathetic innervation to Muller’s muscle or parasympathetic interruption to levator palpebrae superioris

Question 11

Lacrimation

Answer 11

facial nerve - greater petrosal nerve - Vidian’s nerve - IOF - orbit - ophthalmic division of trigeminal nerve - makes you cry

Question 12

Why do you get a runny nose when you cry

Answer 12

Naso-lacrimal duct connected to nasal cavity

Question 13

LR movement

Answer 13

Abduction

Question 14

Sr movement

Answer 14

Eye moves medially

Question 15

SO action

Answer 15

Eye moves down and out

Question 16

IO contraction

Answer 16

Eye goes up and out

Question 17

MR action

Answer 17

Adduction

Question 18

IR action

Answer 18

Down and out

Question 19

Test SR

Answer 19

Look laterally and up

Question 20

Test IR

Answer 20

Look laterally and down

Question 21

Test LR

Answer 21

Look laterally

Question 22

Test MR

Answer 22

Look medially

Question 23

Test IO

Answer 23

look medially and upwards.

Question 24

Test SO

Answer 24

Look medially and downwards

Question 25

Abducens palsy

Answer 25

Eye adducted

Question 26

Oculomotor palsy

Answer 26

Pupils dilated, droopy eyelids, down and out

Question 27

trochlear palsy

Answer 27

Eye turned up and in

Question 28

Sclera action

Answer 28

White fibrous layer that maintains structure

Question 29

Lamina cribosa

Answer 29

Defect that allows entry of optic nerve - blind spot

Question 30

Papilloedema

Answer 30

Optic disc bulges inwards

Question 31

Limbus

Answer 31

Cornea meets sclera

Question 32

retinal detachment tx

Answer 32

corneal buckle

Question 33

Function of cornea

Answer 33

Allows light to pas through - beware abrasion

Question 34

Keratpconus

Answer 34

Cornea thins and forms dome-like structure

Question 35

Iris function

Answer 35

Controls light entering eye

Question 36

Ciliary body function

Answer 36

Controls shape of lens

Question 37

How do you see objects up close

Answer 37

Ciliary muscle contraction = suspensory ligament relaxation = spherical lens and greater focussing power of close up objects

Question 38

What is a cataract?

Answer 38

Cloudy lens

Question 39

Cataracts tx

Answer 39

Surgery to scoop out lens and replace

Question 40

Action of iris

Answer 40

PS causes circular muscles to contract = less light in | Sympathetic causes radial muscles to contract = more light in

Question 41

Horner's sx

Answer 41

Anhydrous, meiosis, ptosis

Question 42

Treatment for dilating pupil

Answer 42

tropic amide and atropine

Question 43

How does pan coast tumour cause Horner's

Answer 43

Pancoast tumour (lung) can cause Horner’s by invasion of sympathetic NS

Question 44

What is your optic disc

Answer 44

axons exit eyeball, no rods or cones (blind spot)

Question 45

Rods

Answer 45

See in black and white but used in low light - located around peripheries

Question 46

Cones

Answer 46

See in colour - red/green/blue rods

Question 47

Macular degeneration

Answer 47

Degeneration of macula - colour blindness and no central vision

Question 48

Retinitis pigmentosa

Answer 48

Congenital retina degeneration = peripheral visual loss

Question 49

What separates anterior and posterior chambers?

Answer 49

iris

Question 50

What separates posterior and anterior chamber

Answer 50

iris

Question 51

What are floaters

Answer 51

Parts of vitreous humour

Question 52

Where is aqueous humour made and absorbed

Answer 52

mAde in ciliary body and absorbed by canal of schlemm