Anatomy

Question 1

what does the optic canal contain

Answer 1

optic nerve and opthalmic artery and vein

Question 2

what bone is the optic canal in

Answer 2

sphenoid

Question 3

what bone is the infraorbital foramen in

Answer 3

maxillary

Question 4

what bone is the superior orbital fissure in

Answer 4

the sphenoid

Question 5

what bone is the supraorbital notch in

Answer 5

frontal

Question 6

why is the ethmoid bone weak

Answer 6

due to the presence of the ethmoid sinuses

Question 7

what is the ‘apex’ of the bony orbit

Answer 7

the optic canal

Question 8

what bones are most likely to break in a ‘blow out’ fracture

Answer 8

medial (ethmoid) and orbital floor (maxilla, )

Question 9

what is a blow out fracture

Answer 9

when a direct blow to the eye increases pressure in eye and cause the fracture of bone/s in the orbit

Question 10

what bones make up the orbital rim. margin

Answer 10

zygoma, frontal, maxilla

Question 11

what sensory deficit can be caused an insult to the infraorbital structure

Answer 11

sensory deficit of the skin of the face (maxillary nerve)

Question 12

what nerve passes through the infraorbital nerve

Answer 12

the maxillary nerve

Question 13

what maintains the shape of the eyelids

Answer 13

the tarsal plate

Question 14

what glands in the eyelids secrete lipids

Answer 14

meibomian glands

Question 15

what is the innervation of the orbicularis occuli

Answer 15

the facial nerve (CNVII)

Question 16

what is the function of the levator palparbi superioris

Answer 16

lifts the upper eyelid

Question 17

what is the innervation of the levator palpabri superioris

Answer 17

occulor motor nerve

Question 18

what is ptosis and what can cause it

Answer 18

inability to lift the upper eyelid

third nerve palsy

Question 19

what happens when the orbicularus occuli contracts

Answer 19

eyes close

Question 20

what covers the iris

Answer 20

the continuous layer of the cornea and sclera

Question 21

what is the sclera covered by

Answer 21

conjunctiva

Question 22

what is the limbus

Answer 22

the corneoscleral junction

Question 23

what does the lacrimal gland produce

Answer 23

tears

Question 24

what innervates the lacrimal gland

Answer 24

parasympathetic CN VII

Question 25

what is the path of tears

Answer 25

``` secreted from lacrimal gland washes over eye pushed by blinking towards medial angle drains through lacromal puncta drains through nasolacromal duct into inferior meatus of the nasal cavity ```

Question 26

what are the three layers of the eye ball

Answer 26

outer- fibrous middle- uvea (vascular layer) inner- retina (photosensitiv

Question 27

what makes up the fibrous layer of the eyeball

Answer 27

sclera (white and fibrous) | cornea (refraction)

Question 28

what makes up the uvea layer of the eyeball

Answer 28

iris ciliary body choriod

Question 29

what are the roles of the ciliary body

Answer 29

control iris, shape of lens, secretion of aques humour

Question 30

what is the role of the choroid body

Answer 30

nutrition and gas exchange

Question 31

what makes up the retina

Answer 31

the optic disc

Question 32

what is uveitis

Answer 32

inflammation of the uvea

Question 33

describe the anterior segment of the eye

Answer 33

in front of lens divided into: anterior chamber- between cornea and iris, contains aqueous humour posterior chamber- between iris and suspensory ligaments, contains aqueous humour

Question 34

describe the posterior segment of the eye

Answer 34

behind the lens, 2/3rd of eye, | contains vitreous body

Question 35

what is in the viteous body

Answer 35

vitreous humour

Question 36

where is a common place for 'floaters' to be

Answer 36

vitreous humour

Question 37

can you replace vitreous humour

Answer 37

no

Question 38

which part of eye does increased pressure cause glaucoma

Answer 38

posterior chamber of anterior segment

Question 39

what is the role of the vitreous humour

Answer 39

holds retina in place and keeps shape of eyeball

Question 40

what is the path of aqueous fluid within the eye

Answer 40

produced by ciliary body circulates within posterior chamber- nourishes lens passes through pupil, into anterior chamber, nourishes cornea reabsorbed into scleral venous sinus (canal of schlemm) at iridocroneal angle

Question 41

what makes up the ciliary body

Answer 41

smooth muscle and blood vessels

Question 42

what is the angle is open and closed angle glaucoma

Answer 42

iridocorneal

Question 43

what can raised intra ocular pressure cause

Answer 43

ischaemia of the retina and glaucoma

Question 44

what is the blood supply to the eye

Answer 44

(central artery (and vein) of the retina from the) opthalmic artery which is a branch of the internal carotid artery ciliary arteries also come off the opthalamic artery

Question 45

what is an end artery

Answer 45

an artery with insufficient anastomoses to maintain viability of the tissue supplied if arterial occlusion occurs

Question 46

what is the venous drainage of the eye and orbit

Answer 46

superior and inferior opthalmic veins combine and go into cavernous sinus also drain anteriorly into facial vein (e.g. veins may drain into this via maxillary sinus)

Question 47

what is the fundus

Answer 47

posterior area where light is focused

Question 48

what makes up the fundus

Answer 48

optic disc, macula, fovea

Question 49

what is the optic disc

Answer 49

point of CN II formation only point of entry/ exit for blood vessels and axons of CN II (as there are no rods or cones overlying the optic disc) ACTS AS A BLIND SPOT

Question 50

what is the macula

Answer 50

part of the fundus which has the greatest density of cones

Question 51

what is the fovea

Answer 51

centre of the macula | area of most acute vision

Question 52

why does a star disappear when you look directly at it

Answer 52

as looking at it with cones (colour) not rods (low light)

Question 53

what are the three layers of the retina (from anterior to posterior)

Answer 53

axons of the ganglion cells ganglion cells photoreceptors

Question 54

where are the retinal veins and arteries in relation to the retina

Answer 54

anterior to the retina

Question 55

what does complete interruption of flow in a retinal artery branch/ retinal vein

Answer 55

loss of an area of visual field corresponding to the area of ischaemia

Question 56

what does complete interruption of flow of the central (end) artery or vein cause

Answer 56

monocular blindness

Question 57

what crosses over at the optic chiasma

Answer 57

nasal retinae

Question 58

where is light from the right visual field processed

Answer 58

left primary visual cortex

Question 59

where is light from the lower visual field processed

Answer 59

in the upper part of the primary visual cortex

Question 60

what are the extrinsic muscles of the eye

Answer 60

superior, medial, lateral and inferior rectus inferior and superior oblique

Question 61

where do the extrinsic muscles attach to the eye

Answer 61

to the sclera

Question 62

what is the action of lateral rectus

Answer 62

abducts (laterally)

Question 63

what is the action of medial rectus

Answer 63

adduction (medially)

Question 64

what is the action of superior rectus

Answer 64

up and in (adduct)

Question 65

what is the action of inferior rectus

Answer 65

down and in (adduct)

Question 66

what is the action of superior oblique

Answer 66

down and out (oblique- out- abduct) (but test by down and in)

Question 67

what is the action of inferior oblique

Answer 67

up and out (oblique-out-abduct)

Question 68

what innervated the lateral rectus

Answer 68

abducens CN VI

Question 69

what innervates the superior oblique

Answer 69

trochlear nerve

Question 70

what does the superior oblique pass through before attaching to the eye

Answer 70

the trochlear

Question 71

what innervates all the extrinsic eye muscles apart from the superior oblique and lateral rectus

Answer 71

CN III- oculomotor nerve

Question 72

how do you test the superior oblique

Answer 72

adduct and down

Question 73

how do you test the inferior rectus

Answer 73

out and down

Question 74

how do you test the superior rectus

Answer 74

out and up

Question 75

how do you test the inferior oblique

Answer 75

in and up