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Opthamology > Anatomy > Flashcards

Flashcards in Anatomy Deck (100)
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1
Q
A

Orbicularis Occuli

2
Q
A

Orbital margin

3
Q
A

Optic canal

4
Q
A

Superior orbital fissure

5
Q
A

Inferior orbital fissure

6
Q
A

Lacrimal groove

7
Q
A

Iris

8
Q

What is the iris covered with?

A

The cornea

9
Q

What is the corneoscleral junction also known as?

A

The limbus

10
Q
A
11
Q

What are the three layers of the eye?

A
  1. Outer fibrous layer
  2. Uvea
  3. The retina
12
Q

Name the two parts of the fibrous layer of the eye and their function

A
  1. The sclera. Protects the eye and acts as an attachment for extraocular muscles
  2. The cornea. Provides 2/3rds of the refractive power
13
Q

Name the 3 parts of the uvea and their function

A
  1. The iris. Controls pupil diameter
  2. The ciliary body. Controls the iris, the shape of the lens and the secretion of aqueous humour
  3. The choroid. Nutrition and gaseous exchange for the other layers.
14
Q
A
15
Q

What does the opthalmic artery travel through to reach the orbit?

A

The optic canal

16
Q
A

Superior rectus muscle

17
Q
A

Lateral rectus muscle

18
Q
A

Medial rectus muscle

19
Q
A

Inferior rectus muscle

20
Q
A

Superior oblique muscle

21
Q
A

Inferior oblique

22
Q
A

Trochlea

23
Q

What numbered cranial nerve is the optic nerve?

A

CN II

24
Q

What is the area in the eye of most actue vision? Why is this?

A

The fovea centralis in the macula. This is where there is the greatest density of cones.

25
Q
A
26
Q

What “end artery” supplies the eye?

A

The central artery of the retina

27
Q

What four veins does blood from the orbit drain into?

A

Forehead vein(s)

Superior opthalmic vein

Facial vein

Inferior opthalmic vein

28
Q

What is the only point of entry into/exit out of the reti afor blood vessels and optic nerve axons?

A

Optic disc

29
Q

Name the three layers of the retina, from posterior to anterior

A
  1. Photoreceptors
  2. The ganglion cells
  3. The axons of the ganglionc cells
30
Q

Why is the optic disc a “blind spot”?

A

There are no photoreceptors

31
Q

Where is the light from objects in the right visual field processed?

A

The left primary visual cortex

32
Q

Where do all the rectus muscles insert into?

A

The sclera, just posterior to the cornea

33
Q

What nerve gives somatic motor innervation to the lateral rectus muscle?

A

Abducent nerve (CN VI)

34
Q

What nerve gives somatic motor innervation to the superior oblique muscle?

A

Trochlear nerve (CN IV)

35
Q

What nerve gives somatic motor innervation ot all of the eye muscles except from the lateral rectus and the superior oblique?

A

Occulomotor

36
Q
A

Internal carotid arteries

37
Q

What bony opening do cranial nerves III, IV and V pass through?

A

Superior orbital fissure

38
Q

What artery lies within the cavernous sinus?

A

Internal carotid

39
Q
A
40
Q

What are the purple arrows at the oottom of this picture showing?

A
41
Q

What nerve supplies

  • The upper eyelid
  • The cornea
  • All of the conjunctava
A

CN V1 The opthalmic nerve (Opthalmic branch of trigeminal)

42
Q

What nerve supplies

  • the skn of the lower eyelid
  • The skin of the maxilla
  • The skin of the ala of the nose
  • The skin/mucosa of the upper lip
A

CN V2 (maxillary nerve)

43
Q

WHat nerve supplies the skin over the mandible and the temporomandibular joint?

A

CN V3 (Mandibular nerve)

44
Q

Describe the conduction of action potential from the sensory part of CN V1

A

Action potentials conducted centrally via CN V1 to the trigeminal ganglion then in the trigeminal nerve to the pons

45
Q

Where does CN V1 (opthalmic branch of trigeminal) leave the cranial cavity?

A

Superior orbital fissure

46
Q

Where does the maxillary nerve leave the cranium?

A

Foramen rotundum

47
Q

Where does the mandibular branch of the trigeminal nerve leave the cranium?

A

Foraman ovale

48
Q

What neurotransmitter do presynaptic sympathetic axons release as the synapse, which stimulates the cell body of the post synaptic axon?

A

Acetylcholine

49
Q

What neurotransmitter do post synaptic sympathetic axons release at the organ to stimulate the organ to respond?

A

Noradrenaline

50
Q

Describe the course of presynaptic sympathetic axons from the CNS to the eyes.

A
  1. Exit spinal cord at the T1 spinal nerve
  2. Ascend with the sympathetic trunk
  3. Synapse in the superior cervical sympathetic ganglion
51
Q

Where do post synaptic sympathetic axons enter once they leave the superior sympathetic ganglion?

A

The internal and external carotid nerves - these are carried alongside the arteries of the same name.

52
Q
A
53
Q

In the parasympathetic division of the nervous system, where is the ganglion located?

A

Within the organ

54
Q

What does the postsympatic parasympathetic axon release onto the organ to stimulate it?

A

Acetylcholine

55
Q

In which cranial nerves do all presynaptic parasympathetic axons leave the CNS?

A

CN II, VII, IX, X

56
Q

What nerve gives somatic motor innervation ot the levator palpebrae superioris?

A

Occulomotor nerves

57
Q

Where does the occulomotor nerve connect with the CNS?

A

The junction between the midbrain and thw pons

58
Q

What nerves supply autonomic axons to conrol the diameter of the iris and the refractive shape of the lens?

A

Ciliary nerves

59
Q

What nerves form the first part of the afferent limb of the blink reflex?

A

Long ciliary nerves

60
Q

Describe the vestibulo - ocular reflex

A

Turns the eyes in the opposite direction tot a head movement to stabilise the gaze

61
Q

Describe the oculocardiac reflex

A

Reflex bradycardia in response to tension of the extraocular muscles or pressure on the eye

62
Q

When are the pupils dilated?

A

Dim light, fight and flight, sick patients

63
Q

What branch of the nervous system dilates the pupil?

A

Sympathetic

64
Q

What do you call a pupil that is enlraged non - physiologically?

A

Mydriatic

65
Q

What muscle is radially arraged and sits around the internal and extrenla circumfrence of the iris?

A

Dilator pupillae fibres

66
Q

What muscle is arraged circularly all around the internal circumfrence of the iris?

A

Sphincter pupillae fibres

67
Q

What is a miotic pupil?

A

A fixed dilated pupil

68
Q

What are the three componenets of the accomodation reflex?

A
  1. Bilateral pupillary constriction (CN III)
  2. Bilateral convergence (medial rotation of both eyes) also CN III
  3. Bilateral relaxation of the len. The lens become spherical due to contraction of the ciliary muscles (CN III)
69
Q
A
70
Q

What are basal tears?

A

There are there all the time and are importnat in corneal health to clean/nourish and hydrate the avascular cornea. The also contain lysozyme. (An enzyme that cn hydrolyse bacterial cell walls.

71
Q

What are reflex tears?

A

Extra tears in response to mechanical or chemical stimulation

72
Q

What is the afferent limb of the tear reflex?

A

CN V1

73
Q

What is the efferent limb of the tear reflex?

A

CN VII (facial nerve)

74
Q

What nerve supplies the lacrimal gland?

A

Facial

75
Q

How does the lens act in response to an object jn the distance? How is this brought about?

A

The lens flattens. This is broght about by relaxation of the ciliary muscle and tightening of the ligament.

76
Q

What needs to happen in order for the ey to focus on something close up?

A

The ciliary muscle contracts, the ligament relaxes and the lens becomes spherical.

77
Q

Does this image represent near or far vision?

A

Far

78
Q

Does this image represent near or far vision?

A

Near

79
Q

Describe the four stage “neurone chain” involved in the pupillary light relfexes

A
  1. Retinal ganglion cells pass vis ipsilateral optic nerve into the opric chiasm and then synapse in the pretectal nucleus in the midbrain.
  2. (This is then bilateral) These second neurones are located entirely within the midbrain and connect to the pretectal nucleus to the next synapse in the Edinger Westphal nucleus.
  3. Signal then passes from the EX nucleus, via CN III and then its inferior divison to synapse in the ciliary ganglion.
  4. Course in the short ciliary nerves to the spincter pulpillae muscles where the response is seen.
80
Q

What is in the Edinger Westphal nucleus?

A

Cell bodies of the parasympathetic axons of CN III

81
Q

What muscles does the superior divison of CN III supply?

A

Superior rectus

Levator palpebrae superioris

82
Q

What does the inferior divison of CN III supply?

A

Medial rectus

Inferior rectus

Inferios oblique

83
Q

What muscles and nerves are involved when looking to the right? (both eyes)

A

Right eye: Lateral rectus (CN VI)

Left eye: Medial rectus (CN III)

84
Q

What muscles and nerves are involved in looking up and to the right?

A

Right eye: Superior rectus & CN III, Lateral rectus & CN IV

Left eye: Inferior oblique & CN III, Medial rectus & CN III

85
Q

What muscles and nerves are involved in looking down and to the right?

A

Right eye: Inferior rectus & CN III, Lateral rectus & CN VI

Left eye: Superior oblique & CN III, Medial rectus & CN III

86
Q

What muscles and nerves are involved in looking to the left?

A

Right eye: Medial rectus & CN III

Left eye: Lateral rectus & CN VI

87
Q

What muscles and nerves are involved in looking up and to the left?

A

Right eye: Inferior oblique & CN III, Medial rectus & CN III

Left eye: Superior oblique & CN III, Lateral rectus and CN VI

88
Q

What muscles and nerves are involved in looking down and to the left?

A

Right eye: Medial rectus & CN III, Superior oblique a& CN III

Left eye: Lateral rectus & CN VI, Inferior rectus and CN III

89
Q

What muscles and nerves are involved in looking up?

A

Both eyes: Superior rectus, Inferior oblique and CN III

90
Q

What muscles/nerves are involved in looking down?

A

Both eyes: Inferior rectus & CN III, Superior oblique & CN IV

91
Q
A
92
Q

What muscle abducts the eyes?

A

Lateral rectus

93
Q

What muscle adducts the eye?

A

Medial rectus

94
Q

What muscles elevates the eye from an abducted position?

A

Superior rectus

95
Q

What muscle depresses the eye from an abducted position?

A

Inferior rectus

96
Q

What muscle elevates the eye from the adducted position?

A

Inferior oblique

97
Q

What muscle depresses the eye from an adducted posititon?

A

Superior oblique

98
Q

What are the structures of the anterior segment of the eyes (from anterior to posterior)?

A

The cornea

Anterior chamber (space between the cornea and the iris which contains aqueous chamber)

Iris

Lens

Ciliary body

Posterior chamber (contains the lens and aqueous humour and is located between the iris and vitreous body

99
Q

What does the posterior segment of the eye contin?

A

Sclera

Choroid

Retina

Vitreous body

100
Q

What is the vitreous body?

A

Structure containing a clear gel that is 98% water that provides the pressure to hold up the retina supported against the choroid.