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Opthamology > Anatomy > Flashcards

Flashcards in Anatomy Deck (91):
1

What are the bones and features of the bony orbit?

Orbital frontal plate
Orbital ethmoid plate
Optic canal
Superior orbital fissure
Infraorbital
Supraorbital notch/foramen

2

What shape is the bony orbit?

Pyramidal shape

3

What makes up the external eyelid?

Orbicularis oculi
Orbital and palpebral parts

4

What is the apex?

Where the optic canal is

5

Where is the optic canal?

Medially placed

6

Where does the vasculature pass through? *?*

Maxillary

7

What sits beneath the external layer of the eye?

Orbital septum
Sheet of fascia - Helps prevent infection spread

8

What glands sit above and below the eye?

Tarsal glands

9

What do tarsal glands secrete?

Lipids
Lacrimal fluid

10

What muscle attaches to the superior tarsus?

Levator palpebrae superiolis

11

What ligaments pull the tarsus to the side to give it its shape?

Lateral/medial palpebral ligament

12

What covers the iris?

Cornea

13

What is a limbus?

A corneoscleral junction

14

What covers the sclera?

Conjunctiva

15

What is the pink/orangey bit at the corners of the eye?

Lacrimal lake

16

Where do tears pass into?

a Puncta (openings)

17

What provides the eye with nourishment?

Conjunctival vessels

18

What is the conjunctival fornix?

Where the conjuctiva over the lower eyelid and over the sclera meet

19

What does the lacrimal gland secrete and what supplies it?

lacrimal fluid
CN VII parasym

20

Where do tears drain to?

Canaliculi and lacrimal sac, down a nasolacrimal duct into the inferior meatus (nose)

21

What is the coloured part of the eye?

The iris

22

What is the pupil?

a hole

23

What are corneal reflections?

Light reflections

24

Does the cornea have a greater curvature?

Yes

25

What makes up the 2 parts of the fibrous outer layer of the eye?

Sclera - musslce attachment
Cornea - 2/3 refractive power

26

What makes up the uvea (vascular layer of the eye)

iris - pupil diameter
ciliary body - controls iris, shape of lens and secretion of aqueous humour
Choroid - nutrition and gas exchange

27

What is refractive power?

Ability to focus light

28

What is the inner layer of the eye?

Retina

29

What is the anterior segment if the eye?

Anterior chamber is between cornea and iris, contains aqueous humour
Posterior chamber is between iris and suspensory ligaments, contains aqueous humour

30

What is the posterior segment of the eye?

behind lens, 2/3rds of eye
contains vitreous body which has vitreous humour.
Vitreous body is a common location for floaters

31

What is a clouding of the lens?

Cataract

32

Where is aqueous circulated?

Ciliary body
then posterior chamber - nourishes lens
passes through pupils
then reabsorbed into sclera venous sinus

33

What angle is involved with glaucoma?

angle between the Iris and the cornea

34

What can cause ishaemia of the retina?

Raised intra-ocular pressure
Can be caused by increased fluid level in the eye

35

What makes up the retina?

Fundus:-
Optic disc
Macula
Fovea

36

What is the optic disc?

Point of CN 2 formation
Only point of entry/exit for vessels
Blind spot

37

What is the macula?

Greatest density of cons

38

What is the fovea?

centre of the macula
Depression, diameter of 1.5mm
area of most acute vision

39

How do you look at the back of the eye?

Fundoscopy

40

What causes monocular blindness?

Complete interruption of flow of the central artery (end artery) or vein

41

Are the optic canal and the optic disc closely anatomically related?

Yes

42

What are the layers of the retina?

Post to Anterior:
1. Photoreceptors
2. ganglion cells
3. axons of the ganglia

43

Where do the retinal veins/arteries lie in relation to the retina?

Anteriorly

44

Where do objects in the right visual field go to be processed?

Left primary visual cortext

45

Where do the vision pathways cross?

The optic chiasma

46

What is the Lateral geniculate nucleus (LGN)

Part of the visual pathway in the thalamus

47

What is the main blood supply of the eye?

Opthalmic artery branch of the internal carotid artery

48

Where does the opthalmic artery pass through?

Optic canal

49

What is the problem with the retinal artery?

It is an end artery

50

Where does the inferior opthalmic vein mainly drain into?

Superior opthalmic vein

51

Where does the orbit drain into?

Facial vein (valveless vein)

52

How many extraocular skeletal muscles are there?

7

53

What are the 4 rectus muscles?

Superior
Inferior
Medial
Lateral rectus

54

Where do the rectus muscle originate from and attach to?

Common tendinous rung to the sclera

55

What are the two oblique muscles?

Superior
Inferior oblique

56

Where do the oblique muscles insert into?

Sclera

57

What does the levator palpebrea superioris do?

Lifts the upper eyelid

58

What innervates the lateral rectus?

CN VI Abducents

59

What innervates the superior oblique?

CN IV Trochlear

60

What innervates the other muscles of the eye?

CN III Oculomotor

61

What eye movements are along the vertical axis?

Abduction/adduction
Direction of gaze

62

What eye movements are along the transverse axis?

elevation/depression
direction of gaze

63

What eye movements are along the anteroposterior axis?

Introsion/extrosion
superior pole of the eyeball

64

Where is the apex of orbit?

Medially placed
*Different from optical axis*

65

What eye muscles don't have secondary movements?

Medial and lateral rectus

66

Where do the secondary movements occur?

From the primary position

67

How do you check the nerve supply of the eye?

Do eye movements one by one

68

What does the lateral rectus do?

Abduct the eyeball only
- CN VI - abducents

69

What does the superior rectus do?

elevate the eyeball only when the eyeball is abducted
CN III - oculomotor

70

What does the inferior rectus do?

Depress the eye when the they eye is in abduction
CN III - oculomotor

71

What does the medial rectus do?

Adduct the eye
CN III 0 oculomotor

72

What does the inferior oblique do?

Elevates the eyeball only when the eye is in adduction
CN III oculomotor

73

What does the superior oblique do?

Depresses the eye only when the eye is in adduction
CN IV trochlear

74

What gives pure elevation of the eyes?

Superior rectus and inferior oblique
They are antagonists - act against each other to lift the eye

75

What gives pure depression?

Superior oblique and inferior rectus
Antagonists as they work together to lower the eye

76

Where does the eyeball sit?

The suspensory ligament of the eye

77

What is diplopia?

double vision

78

Where does the suspensory ligament of the eye attach to?

Zygoma laterally

79

What can result from damage to the infraorbital canal?

General sensory deficit of the facial skin

80

Where does the zygoma rotate when fractured?

Medially towards the floor of the orbit

81

What does CN V1 supply
(opthalmic) general sensory of skin

upper eyelid
cornea
conjuctiva

82

What does CN V2 supply? (maxillary) general sensory of skin

lower eyelid
maxila
ala of nose

83

What does CN V3 supply? (mandibular)
general sensory of skin

mandible
temperomandibular joint
except angle of the mandible supplied by C2 C3 spinal nerves

84

What is the corneal reflex?

Blink reflex

85

What is the afferent limb of the relfex?

Sensory

86

What is the efferent limb of the reflex?

Motor

87

Where are action potentials conducted in the corneal reflex?

Centrally via CN V1 to the trigeminal ganglion then in CN V to the pons

88

Where are action potentials conducted peripherally in the corneal reflex?

In CN VII to the eyelid and orbicularis oculi

89

What does the presynaptic axon release?

Acetylcholine at the synapse

90

What does the postsynaptic axon release?

Noradrenaline at the organ to stimulate the organ

91

What cranial nerves contain presynaptic axons?

3,7,9,10