Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neurology > Eye > Flashcards

Eye Flashcards

1
Q

What are the 5 histological layers of the cornea?

A

1=stratified squamous non-keratinsed epithelium

2=Bowman’s membrane

3=Stroma (regulary arranged collagen)

4=Descemet’s layer

5=endothelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What function does the endothelium of the cornea have?

A

Has a pump that actively keeps out aqueous humor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the pathway of aqueous humor

A

the ciliary body releases aqueous humor into the anterior chamber, at the angle of the anterior chamber is drains through the trabecular meshwork, it then reaches a little tube known as the schlemm’s canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why is the fovea centralis have max visual acuity?

A

packed with cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the lens of the eye

A

A transparent, crystalline biconvex structure which is suspended by zonules from the ciliary body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is lens opacification called?

A

cataract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Function of tear film

A

Cornea moist, wash away particulate foreign bodies, contains antibodies and lysozymes, smooths outer surface of cornea- so smooth surface for refraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

the 3 layers of the tear film?

A

layer 1= mucinous layer overlying corneal epithelium
layer 2= aqueous layer
layer 3= oily layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What nerve stimulates secretion of tears into conjunctival sac?

A

parasympathetic- facial nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What distributes a tear film across the eye?

A

when you blink the sharp lower border of the upper eyelid distributes tear film evenly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What stimulates you to blink?

A

when your eyelids are open, the aqueous component of tears begin to evaporate, and the oily layer becomes to close to the mucin layer.

When these 2 layers touch the tear film breaks up and your eyelid is stimulated to blink

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is refraction?

A

bending of light when it passes from one optical medium to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is refraction in relation to the eye?

A

light waves from an object bend at the cornea, they are bent some more at the lens to form a clear image on the retina.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is accommodation

A

The change that occurs in eyes when it changes focus from a distant (infinity) to a close object (20cm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

When does a lens thicken and what does this help the eye do?

A

A lens thickens during accomodation to help focus on closer objects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the steps of a lens thickening

A

Ciliary muscles contracts making the ciliary body bulge, space in the middle decreases, suspensory ligaments become lax, lens is no longer under stretch and lens becomes thicker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the 2nd step on accommodation

A

pupil constriction via pupillary constrictor muscle around the border of the pupil, via parasympathetic (CNIII) innervation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the 3rd step of accommodation

A

eyes convergence- when you focus on a close object out eyes have to both turn in medially using the medial recti muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the name for perfect vision?

A

emmetrope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is myopia?

A

shortsightedness

distant objects look hazy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is phototransduction?

A

conversion of light energy to an electrochemical response by the photoreceptors (rods and cones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the visual pigment in rods?

A

in the lamellae cell membrane of the rod is a visual pigment called rhodopsin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the visual pigment in cones?

A

in the lamellae cell membrane of cones is visual pigment called opsins S, M and L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What happens when light hits the visual pigment?

A

11-cis retinal sits in the opsins (made from dietary vit-A), when light falls on 11-cis retinal, it isomerises into all-trans retinal

all trans retinal cannot fit in the opsin, so rhodopsin spilts resulting in bleeching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What does bleaching of visual pigment cause?

A

Causes a phototransdution cascade, this is a cascade of reactions causing hyperpolarisation, transmitting an impulse, which becomes an action potential in the optic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What role does vitamin A play in visual pigment?

A

visual pigment regeneration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

signs of vitamin A deficiency in the eye

A

Bitot’s spot on conjunctiva, corneal ulceration, corneal melting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How can your visual field be tested?

A

by confrontation test or automated perimetry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Where do fibres from the optic tract synapse?

A

fibres from the optic tract synapse at the Lateral geniculate body of the thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Describe the steps of a visual pathway

A

All fibres from the eye pass through the optic nerve to the optic chiasma,
the nasal fibres cross to the opposite side, thus the optic tract contains fibres from the temporal half of the ipsilateral eye and the corssed-over nasal fibres from the contralateral eye .

fibres from the optic tract synapse at the LGB of the thalamus.

optic radiation passes behind the internal capsule to reach the primary visual cortex in the occipital lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What causes contralateral homonymous hemianopia?

A

right optic tract damage, optic radiation damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What causes bitemporal hemianopia

A

optic chiasma disrupted in the middle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Role of intrinsic muscles?

A

control pupil diameter and help alter lens curvature to enable us to see near objects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Role of extrinsic muscles?

A

move the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What do the recti muscles arise from?

A

they arise from the apex of the orbit from an annular fibrous ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Where does the superior oblique muscle arise from

A

from the roof of the orbit posteriorly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Where does the inferior oblique muscle arise from

A

the floor of the orbit anteriorly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what does LPS stand for and what does this muscle do?

A

levator palpebrae superioris

this muscle elevates the eyelids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What does strabismus mean

A

squint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Types of squint?

A

Esotropia- manifest convergent squint, one eye is deviated inward

Exotropia- manifest divergent squint, one or both eyes look outward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Functional consequences of squint?

A

Amblyopia, diplopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is amblyopia?

A

lazy eye

brain supresses the image of 1 eye leading to poor vision in that eye without pathology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is diplopia?

A

double vision

usually occurs in squints as a result of nerve palsies

44
Q

Where do fibres destined to activate pupillary reflex go to

A

Rather than go to LGB, they leave the optic tract and go to the midbrain, to the IIIcn nucleus- Edinger-Westphal nucleus

45
Q

Where do parasympathetic fibres go after the Edinger-Westphal nucleus?

A

preganglionic fibres go to and synapse in ciliary ganglion, postganglionic fibres go through short ciliary nerves to constrictor pupillae and then there is pupillary constriction on both sides

46
Q

Pupil abnormalities?

A

aniscocoria, pupils react differently to light

47
Q

Causes of absent/ abnormal pupillary reflex

A

diseases of retina (detachment, degenerations or dystrophies), diseases of optic nerve (optic neuritis), diseases of the IIIcn (efferent limb)

48
Q

What is ptosis?

A

drooping of eyelid

49
Q

What is the conjunctiva?

A

A thin vascular membrane that covers the inner surface of eyelids and loops back over the sclera

50
Q

What gland is affected in external stye?

A

sebaceous gland

51
Q

What gland is affected in an internal stye?

A

meibomian gland

52
Q

Name of corneal transplant?

A

keratoplasty

53
Q

What is trabeculectomy and what is this surgery used for?

A

removal of a block of tissue in eye to allow AH to drain, used in glaucoma

54
Q

What is normal position of eyelids?

A

top eyelid= hides top 2mm of cornea

bottom eyelid= at level of corneosclera junction

55
Q

Right eye can’t adduct cause and when asked to look froward right eye looks medially?

A

6th nerve palsy

56
Q

Ptosis and can only move eye laterally diagosis?

A

IIIcn palsy

57
Q

Inferioir oblique overworking, can’t depress left eye

A

Left 4th nerve palsy

58
Q

How can retinal detachment occur due to trauma?

A

peripheral retina to tear, vitreous gel gets liquified, liquid vitrous pushed through the retinal tear and detaches it

59
Q

Drooping eyelid cause?

A

IIIcn palsy- due to LPS muscle

60
Q

Inability to close eyelid cause?

A

Left VIIn palsy

61
Q

Describe neuron cells

A

structural and functional unit, these are excitable cells that carry action potentials

Neuron= multiple dendrites and one axon

62
Q

Describe glial cells

A

non-excitable supporting cells that are much smaller than neurons

63
Q

What does the cell body of a nucleus contain?

A

nucleus (loose chromatin, prominent nucleolus), mitochondria, rER (nissl bodies), diffuse golgi apparatus

64
Q

What is the difference in the cytoplasm in a cell body compared with an axon?

A

cytoplasm in the cell body is perikaryon and in axon is axoplasm

65
Q

What is the myelin sheath formed by?

A

schwann cells in PNS

Oligodendrocytes in CNS

66
Q

What type of matter would you find neuronal cell bodies?

A

grey matter

67
Q

What type of matter would you find myelinated axons?

A

white matter

68
Q

Types of neurons?

A

interneuron motor (multipolar) and sensory neurons (pseudounipolar) and olfactory mucosa retinal nerve fibres (bipolar)

69
Q

Types of CNS glial cells?

A

Astrocytes (BBB)
Oligodendrocytes (myelination)
Microglia (phagocytosis, scar tissue formation)
Ependymal cells (line ventricles)

70
Q

Types of PNS glial cells?

A 
Schwann cells (myelination)
Satellite cells (surround neuronal cell bodies
71
Q

What are the lateral ventricles?

A

C-shaped cavities which lie in the cerebral hemispheres

72
Q

Where does the 3rd ventricle lie?

A

in the diencephalon

73
Q

Where does the cerebral aqueduct lie?

A

within the midbrain

74
Q

where does the 4th ventricle lie and what is the shape of this ventricle?

A

between the pons and the medulla, and the shape is a diamond

75
Q

What connects the 3rd ventricle with the lateral ventricles?

A

the interventricular foramen

76
Q

what is found inside the ventricles?

A

CSF

77
Q

What is found in the subarachnoid space and what layers of the meninges is this space between?

A

CSF

between the pia and arachnoid layer

78
Q

Where is CSF formed?

A

by the choroid plexus in each ventricle

79
Q

Where is CSF absorbed

A

by the arachnoid villi into the saggital sinus

80
Q

Wjere are the receptors for the olfactory nerve?

A

in olfactory epithelium of the nasal cavity

81
Q

What is the component of the olfactory nerve?

A

special sensory- smell

82
Q

WHat is the component of the optic nerve?

A

special sensory- vision

83
Q

name 2 clinical applications of the optic nerve?

A

increase in CSF pressure causes papilloedema, section of right optic nerve causes blindness through right eye

84
Q

What is the component of the oculomotor nerve?

A

somatic motor- extraocular muscles and levator palpebrae superioris

visceral motor- parasympathetic to pupil causing constriction and to ciliary muscle causing accomodation of the lens

85
Q

What is the clinical application of the oculomotor nerve?

A

drooping of upper eyelid, eyeball abducted and pointing downwards, no pupillaryreflex, no accommodation of lens

86
Q

components of the trochlear nerve?

A

somatic motor- superior oblique

87
Q

Clinical application of the trochlear nerve

A

diplopia when looking down

88
Q

Abducent nerve components

A

somatic motor- lateral rectus

89
Q

clinical application of abducent nerve

A

medial deviation of the affected eye causing diplopia

90
Q

Components of the trigeminal nerve- ophthalmic division

A

general sensory- cornea, forehead, scalp, eyelids, nose and mucosal of nasal cavity and sinuses

91
Q

Components of the trigeminal nerve- maxillary division

A

general sensory- from face over maxilla, maxillary teeth, temperomandibular joint, mucosa of nose, maxillarty sinuses and palate

92
Q

Components of the trigeminal nerve- mandibular division

A

general sensory- from face over the mandible, mandibular teeth, temperomandibular joint, mucosa of mouth and anterior 2/3rds of tongue

somatic motor- muscles of mastication, part of diagastric, tensor veli palatinin and tensor tympani `

93
Q

Clinical application of facial nerve

A

paralysis of muscle of mastication, loss of conreal or sneezing reflex, loss of sensation in the face, trigeminal neuralgia

94
Q

What are the components of the facial nerve?

A

somatic motor- muscles of facial expression and scalp, stapedius of middle ear and part of digastric muscle

visceral motor- parasympathetic innervation of submandibular and sublingual salivary glands, lacrimal glands, glands of nose and palate

special sensory- taste from anterior 2/3rd of tongue and soft palate

general sensory-from external acoustic meatus

95
Q

Facial nerve clinical application

A

bells palsy- cannot frown, close eyelid or bare teeth

96
Q

Vestibulocochlear components

A

special sensory- vestibular sensation from semicircular ducts, utricle, saccule gives sense of position and movement
and hearing from spiral organ

97
Q

Clinical application of vestibulocochlear

A

tinnitus, deafness, vertigo, nystagmus

98
Q

What are the components of the glossopharyngeal nerve?

A

special sensory- taster from posterior 3rd of tongue

general sensory- cutaneous sensations from middle ear and posterior oral cavity

Visceral sensory- sensation from carotid body and carotid sinus

Visceral motor- parasympathetic innervation of parotid gland

somatic motor- to stylopharyngeus, helps with swallowing

99
Q

Clinical application of the glossopharyngeal nerve

A

loss of gag reflex and taste from back of tongue

associated with injuries to CNs X and XI, this is known as jugular foramen syndrome

100
Q

What are the components of the vagus nerve?

A

special sensory- taste from epiglottis and palate

general sensory- sensation from auricle, external acoustic meatus

visceral sensory- from pharynx, layrnx, trachea, bronchi, heart, oesophagus, stomach, intestine

Visceral motor- to pharynx, larynx, palate and oesophagus

101
Q

Clinical application of the vagus nerve

A

damage to pharyngeal branches causing difficulty swallowing and damage to laryngeal branches causing difficulty in speaking

102
Q

What is the component of the accessory nerve?

A

somatic motor- striated muscle of soft palate, pharynx and larynx, and to sternocleidomastoid and trapezius

103
Q

Clinical application of the accessory nerve?

A

weakness in turning head and shrugging shoulders

104
Q

Components of the hypoglossal nerve

A

somatic motor- to muscles of tongue

105
Q

Clinical application of hypoglossal

A

vulnerable to damage during tonsillectomy

causes paralysis and atrophy of ipsialteral half of tongue, tip deviates towards affected side

106
Q

Causes for gradual loss of vision?

A

cataract, glaucoma, age related macular degeneration, diabetic neuropathy

107
Q

Causes for sudden loss of vision?

A

anterior ischaemic optic neuropathy- non-arteritic and arteritic

Neurology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions