Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Neurology physiology > Vision > Flashcards

Vision Flashcards

1
Q

List 3 layers of the eye from outer to inner

A

1- Sclera and Cornea
2- Uvea ( choroid , ciliary body , iris )
3- Retina

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

What is the function of the Sclera

A

1- Protect eye from trauma
2- Maintains intraocular pressure
3- Allows attachment of the extra ocular muscles

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

What is Glaucoma

A

When pressure in eye is high enough to cause damage

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

How many extra ocular muscles are there for each eye

A

Six

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

What is the function of the choroid

A

1- Supplies nutrients and oxygen to outer retina

2- pigment absorbs light

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

The blood vessels of the retina only supply with Half? what’s happening with the other half

A

The inner half. The outer half is supplied by the underlying choroid

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

What is the most vascular part of the body

A

The choroid

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

What is the clinical relevance of the choroid

A

Macular degeneration

- Age related condition affecting the macula , the centre of the retina used for central vision

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

Wet vs Dry macular degeneration

A

Wet: sheet of vascular tissue comes up from the choroid , grows anteriorly under the retina and then goes into the retina = bleeds and leaks

Dry: Thinning of the macula

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

80 year old patients comes in with loss of central vision, what is the first though ?

A

Macular degeneration

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

Causes of Macular degeneration ( risk factors )

A

1- Age
2- SMoking
3- Fam history

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

What is Myopia

A

Short sightedness

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

What is Hypermetropia

A

Long sightedness

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

What is astigmatism

A

Front of the eye , the cornea has an abnormal curvature that is steeper in one axis than another.
Can happen with short or long sightedness

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

What is the function of the cornea

A

Most of refraction of light occurs at the cornea. At the air tear film interface ( as light passes from air to water medium )

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

What are the two clinically relevant layers of the cornea

A

1- Epithelium : constantly regenerated

2- Endothelial cells : maintain/prevent dehydration of stroma

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

What is the clinical relevance of the cornea

A

Corneal abrasion : scratch on the surface of the cornea , in the epithelium –> takes a few days to heal , will be very photophobic until it’s healed

Opaque cornea : needs corneal transplant

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

When would a cornea under blue light and with orange fluorescent drops show up as green

A

In a corneal abrasion.

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

Would you need systemic immunosuppression after cornea transplant

A

No because cornea is avascular

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

What is the function of the iris

A 
Smooth muscles controlling pupil 
1- Sphincter pupillae constricts pupil 
- supplied by PNS 
2- Dilator pupillae dilates pupil 
- supplied by SNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When SNS is on the pupil dilates or constricts ?

A

Dilates

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

What is Corner syndrome

A

interruption to sympathetic supply to the eye , causing unopposed parasympathetic stimulation ( constricting )

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

The front part of the eye is filled with ?

A

Aqueous humour

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

What produces the aqueous humor

A

The ciliary body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Explain the flow of aqueous humor
1- goes between lens and iris 2- into anterior chamber 3- between cornea and iris 4- down through trabecular meshwork
26
Where is the blockage of aqueous humor in acute glaucoma
Between the pupil and iris causing increase in pressure
27
What is glaucoma
Imbalance between rate of production and drainage of aqueous humor = causing raised intraocular pressure
28
What are the functions of the of the ciliary body
1- produce aqueous humor | 2- ciliary muscle contracts when we focus on near objects
29
Process of ciliary muscle contracting when focusing on near objects is called ?
Accommodation
30
What is presbyopia
Age related reduction in ability to accommodate , mainly due to lens stiffness
31
What is the treatment for presbyopia
Reading glasses : very focal glasses
32
What is the clinical relevance of the lens
Cataract : Lens is opaque/ foggy
33
What is the vitreous humor
Found posterior to lens , a hydrated Gell with collagen fibrils. Attached to retina
34
Any traction to vitreous results in pull on ?
Retina
35
What is posterior vitreous detachment
Vitreous liquifies & collapses in on itself = pulls on retina , causes symptoms of flashes and floaters
36
What are the two retina layers
1- Neural layers : made 9 layers | 2- Retinal pigmented epithelium ( RPE )
37
What is the function of the retina ( cones and rods )
Rods perceive light intensity ( at periphery ) | Cones in the Fovea, in the centre of the macula perceive colour
38
What is the optic disk
Where axons form the ganglion cells merge to form the optic nerve. The blind spots since there's no photoreceptors there
39
The ophthalmic artery is branch of the ?
Internal carotid artery
40
What are the branches of the ophthalmic artery
1- Central retinal artsy
41
Explain the course of the central retinal artery
Runs beside the central optic vein in the optic nerve. Pierces the eyeball through the lamina cribrosa. End artery and supplies inner 2/3 of the retina
42
What is the lamina cribrosa
A hole ( sieve like thinned area ) in the sclera where the optic nerve goes into the eyeball. Central retinal vessels go through it with the optic nerve into the eyeball.
43
What are the optic disc rim and cup
Rim : Where the ganglion cells running towards the optic disk turn 90 degrees to form optic nerve , creates a darker rim around the optic disc Cup : middle of optic disc that is just bare sclera, thin sieve like part that allows entering of optic nerve & vessels
44
What is the clinical relevance of the central retinal artery
The only supply of blood to the retina. | Usually blocked by clot from the internal carotid artery
45
Pale colour of retina indicates what
Blockage of blood flow to retina
46
Thinner vessels in the retina are the ?
The arteries
47
Clinical features of the macula
1- Blood vessels go around it, not through it 2- darker in the middle 3- To the temporal side of the disc
48
Central of the macula is known as the ?
Fovea
49
What is a clinical indication of central retinal artery occlusion
Cherry red spot : | Pale retina but fovea is very red spot
50
What are the 4 branches of the central retinal artery
1- Supertemporal 2- infro temporal 3- inferonasal 4- superonasal
51
Is the fovea vascular or avascular
Avascular
52
Where is the capillary network most dense in the retina
in the Macula
53
How can raised intracranial pressure be seen in the eye , How will it look like
Optic nerve is surrounded by dude matter and arachnoid sheaths so raised ICP will be submitted along the subarachnoid space. Thin walled central vein will be compressed causing congestion and thus papilloedema. Clinical Features : Contour of disc is indistinct , looks swollen , veins look compressed , red streaks around the discs
54
What branches of the opthalmic artery supply the uveal tract
Ciliary arteries : 1- Long posterior ciliary 2- short posterior ciliary 3- Anterior ciliary
55
The components of the uveal tract are
Choroid , ciliary body , iris
56
What is the aura serrata
anteriorly the retina finishes at the Wavy line called aura serrata . Where you would go through in surgery rather than the retina and damaging it
57
The space between the RPE cells and the photoreceptors is a potential for what
Potential to open up , where retinal detachment usually happens. Aka sub retinal space
58
What forms the outer blood retinal barrier
The tight junctions of the RPE cells form the barrier
59
The outer blood retinal layer gives the retina ?
1- immune protection | 2- ability for exchange of substances
60
RPE live in what type of environment
Highly oxidative
61
Is oxygen extracted in the choroid
Little oxygen is extracted , despite the high blood flow
62
What is a by product of oxidative damage in the RPE
Lipofuscin ; orange spots in the eye
63
If not much oxygen is extracted in the choroid what is the purpose of the choroid having a high blood flow
Choroid takes away heat from the RPE ( which absorbs light )
64
Explain the visual cycle
1- photo of light is absorbed in the protoreceptors by 11-cis retinal 2- results in change in its conformation = bleaching 3- 11 cis-retinal attached to opsin changes to all-trans retinal & free opsin 4- All-trans retinal is dumped to RPE which gives it back to photoreceptors ( recycles )
65
What does the RPE secrete
VGEF : vascular endothelial growth factor
66
Excess VGEF can cause what in the retina
Leaking from retina , due to too much fenestration of choroid
67
Are ganglion retinal cells myelinated ? What is the condition associated with this ?
They are not myelinated. | Myelinated ganglion cells are a congenital condition , doesn't affect day to day , might have bigger blind spots ?
68
What is an OCT
Optical coherence tomography | - imaging of the layers of the eye
69
What is the route of the Optic nerve out of the eye ball
Orbital portion of optic nerve goes out of eye ball , passes through optic canal in sphenoid bone , then backwards and upwards to floor of 3rd ventricle. joins other optic nerve to form optic chasm
70
What are the important relations of the optic chasm
Laterally : carotid arteries Inferiorly : pituitary gland Fibres from the nasal side of eye cross ( temporal view )
71
What is the most common cause of optic chasm problems and what would the signs be
Cause : pituitary adenoma | Signs : crossing fibres of nasal side are squeezed causing missing of temporal side vision of each eye
72
What are the optic tracts
Emerge from posterior corners of the optic chasm. Travel posterolaterally. Most of the fibres synapse in the Lateral geniculate body. Then go to primary visual cortex via optic radiation
73
Same side of each eye vision being effected is called
Homonymous hemianopia
74
Problem with left optic tract/ radiation is known as
Right homonymous hemianopia
75
Explain Pupillary light reflex
1-in the optic tract : Most fibres synapse at the LGB , but some leave before LGB and synapse at pretetal nucleus 2- goes to Edinger Westphal nucleus of both sides 3- stimulates third cranial nerve to the ciliary ganglion 4- causes contraction of pupil in iris
76
Afferent limb of the light reflex is controlled by with CN
CN2 ( optic nerve )

Neurology physiology (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions