Anatomy of the Orbit and Eye

Question 1

name the bones of the orbit

Answer 1

frontal ethmoid maxilla zygomatic sphenoid lacrimal

Question 2

the nasal bone does not make up the orbit: T or F?

Answer 2

T

Question 3

how many bones contribute to the orbit?

Answer 3

6

Question 4

what is the function of the supra/infraorbital foraminae?

Answer 4

allow passage of supra/infraorbital neurovascular bundles

Question 5

what shape is the orbit considered to take?

Answer 5

pyramidal shape

Question 6

what makes up the apex of the pyramidal shape of the orbit?

Answer 6

optic canal

Question 7

what makes up the floor of the orbit?

Answer 7

maxilla

Question 8

what makes up the medial wall of the orbit?

Answer 8

ethmoid

Question 9

what makes up the lateral wall of the orbit

Answer 9

sphenoid

Question 10

what makes up the orbital rim?

Answer 10

superior, inferior, medial, lateral margins of the orbit

Question 11

what protects the eye from direct damage?

Answer 11

the orbital rim

Question 12

which is more anterior: superior orbital margin or inferior orbital margin

Answer 12

superior

Question 13

what makes up the superior margin of the orbit

Answer 13

frontal

Question 14

what margins of the orbit are at risk of an orbital blowout fracture?

Answer 14

medial wall floor

Question 15

symptoms of an orbital blowout fracture?

Answer 15

loss of sensation in face sight problems

Question 16

what is diplopia?

Answer 16

double vision

Question 17

what constitutes the most external layer of the eyelid?

Answer 17

orbicularis oculi muscle

Question 18

name the 2 parts of the orbicularis oculi muscle and their location?

Answer 18

orbital= goes round whole orbit

palpebral= lower eyelid

Question 19

what does the middle layer of the eyelid contain

Answer 19

orbital septum (fascia) ligaments

Question 20

main role of the orbital septum?

Answer 20

prevent infection

Question 21

which muscle of the eyelid allows the eye to screw up?

Answer 21

orbital part of the oculi

Question 22

what are tarsi

Answer 22

half moon bands of connective tissue that make up the eyelids

Question 23

what muscle is responsible for lifting the eyelid up?

Answer 23

levator palpebrae superioris

Question 24

another name for mueller’s muscle?

Answer 24

superior tarsal muscle

Question 25

which part of the eye is avascular?

Answer 25

cornea

Question 26

what is the white of the eye called?

Answer 26

sclera

Question 27

what covers the white of the eye?

Answer 27

conjunctiva

Question 28

where is the lacrimal gland located?

Answer 28

laterally on the brow bone

Question 29

name the part of the eye that contains your eye colour

Answer 29

iris

Question 30

what is the limbus

Answer 30

the grey area surrounding the iris and the sclera

Question 31

what is the cornea?

Answer 31

translucent covering of the iris

Question 32

the conjunctiva does not cover the cornea: T or F?

Answer 32

T

Question 33

what is the dot on the medial lower eyelid called?

Answer 33

punctum

Question 34

why do we get runny noses when we cry?

Answer 34

tears drain via the lacrimal sac into the nasolacrimal duct which reaches inferior meatus in nose

Question 35

what nerve controls production of lacrimal fluid by the lacrimal gland?

Answer 35

CN VII

Question 36

name the 3 layers of the eye

Answer 36

fibrous uvea retina

Question 37

name the 2 parts of the fibrous layer of the eye

Answer 37

cornea sclera

Question 38

main source of refractive power of the eye?

Answer 38

cornea

Question 39

3 main components of the uvea?

Answer 39

iris ciliary body choroid

Question 40

what does the iris control?

Answer 40

diameter of the pupil

Question 41

what does the ciliary body control?

Answer 41

iris shape of lens secretion of aqueous humour

Question 42

which layer of the eye contains its vasculature?

Answer 42

uvea

Question 43

what separates the anterior and poster segments of the eye?

Answer 43

the lens

Question 44

which segment of the eye contains vitreous humour?

Answer 44

posterior

Question 45

which segment of the eye contains aqueous humour?

Answer 45

anterior

Question 46

how does the cornea get nutrition if it doesn't have a blood supply?

Answer 46

via the lacrimal gland and aqueous fluid

Question 47

name a common area of the posterior segment for floaters and why

Answer 47

vitreous body as vitreous humour is very gel like so can stick

Question 48

what is a cataract?

Answer 48

clouding of the lens

Question 49

what is closer to the iris: the iridocorneal angle or limbus?

Answer 49

iridocorneal angle

Question 50

what is responsible for the pressure of the eye?

Answer 50

aqueous humour

Question 51

describe the path of aqueous humour from its production

Answer 51

secreted by ciliary processes circulates in posterior chamber to nourish lens passes into anterior chamber to nourish cornea reabsorbed at the iridocorneal angle by the scleral venous sinus

Question 52

blood supply to the uvea?

Answer 52

ciliary artery

Question 53

consequences of raised intra-ocular pressure?

Answer 53

ischaemia of the retina glaucoma

Question 54

main arterial supply to the eye?

Answer 54

opthalmic artery

Question 55

what is the opthalmic artery a branch of?

Answer 55

internal carotid artery

Question 56

name the artery that travels through the centre of the optic nerve?

Answer 56

central artery of the retina

Question 57

why can occlusion of the central artery of the retina cause ischaemia?

Answer 57

it is an end artery

Question 58

main blood supply to the retina?

Answer 58

central artery and vein of the retina

Question 59

name the different routes of venous drainage of the eye

Answer 59

via superior/inferior opthalmic veins -\> cavernous sinus anteriorly into the facial vein

Question 60

how can an infection of the upper lip/external nose cause an infection of the brain?

Answer 60

infection will drain into the facial vein

Question 61

what is the back of the eye called?

Answer 61

fundus

Question 62

at what part of the retina does the optic nerve form?

Answer 62

CN 2

Question 63

which part of the retina does not contain photoreceptors?

Answer 63

optic disc

Question 64

what part of the retina is known as the blind spot?

Answer 64

optic disc

Question 65

what part of retina contains the most cone cells and why?

Answer 65

macula, needs them for acute vision

Question 66

where is the fovea located?

Answer 66

centre of macula

Question 67

name the layers of the retina from anterior to posterior

Answer 67

A Good Photo axons of the ganglion ganglion photoreceptors

Question 68

is the optic disc located more on the nasal or temporal side on fundoscopy?

Answer 68

nasal

Question 69

consequence of complete interruption of flow in a retinal artery/vein?

Answer 69

loss of an AREA of visual field

Question 70

consequence of complete interruption of flow of the central artery or vein?

Answer 70

monocular blindness

Question 71

what area of both eyes would light from the right visual field hit?

Answer 71

right eye- nasal side left eye- temporal side

Question 72

what area of both eyes would light from the left visual field hit?

Answer 72

left eye- nasal right eye- temporal

Question 73

what part of the visual cortex is light from the right and left visual fields processed by?

Answer 73

right visual field- left primary visual cortex left visual field- right primary visual cortex whichever eye has used the nasal retina to absorb the light will be the side of the visual cortex used

Question 74

how may extraocular muscles are there?

Answer 74

7

Question 75

are the extraocular muscles of the eye skeletal or smooth muscle?

Answer 75

skeletal

Question 76

name the 4 rectus muscles

Answer 76

superior rectus inferior rectus medial rectus lateral rectus`

Question 77

origin of the rectus muscles?

Answer 77

common tendinous ring

Question 78

insertion of the rectus muscles?

Answer 78

sclera

Question 79

name the non-rectus extraocular muscles

Answer 79

superior oblique inferior oblique levator palpebrae superioris

Question 80

name the somatic motor innervation of the extraocular muscles (use mnemonic)

Answer 80

LR6 (lateral rectus = CN6) SO4 (superior oblique = CN 4) AO3 (all others = CN3)

Question 81

what plane would the eyes move if the were on the vertical axis?

Answer 81

they would abduct and adduct as they would move horizontally

Question 82

in what direction would the eyes move if they were on the transverse axis?

Answer 82

elevation/depression as they would be moving up and down (transverse=horizontal)

Question 83

what direction would eyes move if they were in the anteroposterior axis?

Answer 83

intorsion extorstion

Question 84

how do you isolate eye muscles so you know you're only testing one muscle?

Answer 84

line up eye gaze to the plane being tested

Question 85

name the 3 axes of the eyeball

Answer 85

transverse anteroposterior vertical

Question 86

what does the lateral rectus muscle do/

Answer 86

abducts eyeball

Question 87

how can you solely test for superior/inferior rectus function?

Answer 87

ask patient to abduct eye to get it in the right plane ask them to elevate/depress eye

Question 88

what muscles can be isolated when you ask the patient to adduct the eye?

Answer 88

infraorbital- ask to elevate supraorbital- ask to depress

Question 89

what muscles of the eye are responsible for elevation?

Answer 89

superior rectus inferior oblique

Question 90

what muscles of the eye are responsible for depression?

Answer 90

superior oblique inferior rectus

Question 91

name the components of the uvea from anterior to posterior

Answer 91

iris ciliary body ciliary vein

Question 92

2 muscles in charge of pupil size?

Answer 92

dilator pupillae sphincter pupillae

Question 93

what part of the retina will light from the above part of the visual field go to?

Answer 93

lower nasal