Week 130 - Ophthalmology General Flashcards

1
Q

What is emmetropia?

A

Normal refractive state of the eye (aka normal vision)

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

What lens do you use to correct hypermetropic vision?

A

(long-sighted) - Convex lens

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

What lens do you use to correct myopic vision?

A

Concave lens

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

What receptors are situated on the circular muscle of iris?

A
M3 receptors (parasympathetic)
-> constricting pupil
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What receptors are situated on the radial muscle of iris?

A

β1 receptors (sympathetic)

-> dilating pupil

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

At what receptor does Atropine act and what are its effects (with regards to the eye).

A

M3 (antagonist) - Pupil dilation

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

At what receptor does Homatropine act and what are its effects (with regards to the eye).

A

M3 (antagonist) - Pupil dilation

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

At what receptor does Cyclopentolate act and what are its effects (with regards to the eye).

A

M3 (antagonist) - Pupil dilation

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

At what receptor does Tropicamide act and what are its effects (with regards to the eye).

A

M3 (antagonist) - Pupil dilation

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

At what receptor does Phenylephrine act and what are its effects (with regards to the eye).

A

α1 (agonist) - Pupil dilation

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

The anterior retina is supplied by which artery?

A

Central Retinal artery

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

What is supplied by the posterior ciliary arteries?

A

Optic nerve head, fovea/macula, posterior retina and the photoreceptors
Also Choroid

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

What visual acuity is considered as “legally blind”?

A

6/60

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

What is scintillating scotomata?

A

“water running down window, kaleidoscope pattern” (symptom of migraine (the aura), emboli and giant cell arteritis)

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

A 63-year old male attended his optometrist complaining of “spots before the eyes”. Suggest two causes of these symptoms.

A

1) Posterior vitreous detachment
2) Vitreous haemorrhage
3) Posterior segment inflammation (uveitis)

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

A 30 year old male presents with blurred vision in R eye, dull ache + red (acute). He takes mesalazine for UC. Likely diagnosis?

A

Uveitis

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

Name THREE glands in the eyelid

A
Sebaceous glands (glands of Zeis)
Ciliary glands (glands of Moll) - modified sweat glands
Tarsal glands - pour oily secretion onto the margin of lid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name TWO muscles of the eyelids

A

Orbicularis oculi - closes eyelids

Levator palpebrae superioris - raises the upper lid

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

What passes through the nasolacrimal canal?

A

Nasolacrimal duct - carries tears from lacrimal sac into the nasal cavity

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

What passes through the Inferior Orbital fissure?

A

Zygomatic Branch of Maxillary Nerve
Inferior ophthalmic vein
Sympathetic Nerves

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

What passes through the Superior Orbital fissure?

A

Lacrimal Nerve, Frontal Nerve
Trochlear Nerve, Oculomotor Nerve, Abducent Nerve
Nasociliary Nerve, Superior Ophthalmic Vein

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

Where is Aqueous Humour found and where is it secreted from?

A

Anterior + Posterior Chambers
Secretion from ciliary processes
It then ends up flowing into the canal of Schlemm
Nourishes cornea + lens

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

Where is Vitreous Humour found and where is it secreted from?

A

Transparent gel filling eyeball

Not actively replaced

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

What is an EFFERENT PUPILLARY DEFECT, and what is signifies?

A

One eye remains dilated regardless of which eye light is shone into. Lesion in efferent limb (e.g. third nerve palsy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is a Relative AFFERENT PUPILLARY DEFECT, and what it signifies?
Both eyes dilate when light is swung across from normal eye, and shone into affected eye. Lesion anterior to chiasm
26
Which muscles insert into the Annulus of Zinn?
Lateral Rectus, Medial Rectus, Superior Rectus, Inferior Rectus, Superior Oblique
27
What is the innervation of the muscles of the orbit?
LR6 SO4 3
28
Where does the occulomotor nerve originate (names of nuclei)?
Somatic Motor Nucleus (voluntary) | Edinger Westphal Nucleus (accomodation + constriction)
29
Which nerve is most commonly injured when Intra-cranial pressure rises?
Abducent Nerve - causes medial deviation of eye + diplopia
30
What are the functions of Ciliary Ganglion?
Sensation of part of eye Pupilary dilation + elevation of upper eyelid (sympathetic) Pupillary constriction and accomodation (parasympathetic)
31
What are the symptoms (3) of Horner's Syndrome?
Ptosis, Miosis (constriction of pupils), Anhidrosis (lack of sweat)
32
What are the causes of Horner's Syndrome?
1) Pancoast tumour of lung 2) Thoracic aortic aneurysm 3) Trauma 4) Compression along sympathetic chain
33
What would the position of eye be in occulomotor nerve palsy?
Dilated pupil + eye down and out
34
What is hypertensive retinopathy?
damage to retina due to HIGH BP
35
What is Optic Neuritis?
Inflammation of optic nerve (may cause complete or partial loss of vision)
36
What is Strabismus?
Eyes not properly aligned with each other
37
What is Nystagmus?
Eye moving in a "jerky" fashion
38
What are the two types of Glaucoma?
Open Angle - canal of Schlemm blocked | Closed Angle - iris obstructs trabecular network and subsequently the canal of Schlemm
39
What are the secondary causes of Glaucoma?
Inflammation/uveitis Trauma Drugs (e.g. steroids) Diabetes/neovascular
40
What is the most common malignant intraocular tumour of children?
Retinoblastoma (Flexner-Wintersteiner rosettes on inspection)
41
What is a cataract?
Opacification of the lens due to denaturation of proteins in lens fibres - loss of visual acuity and contrast
42
What is Giant Cell Arteritis?
Inflammation of large + medium sized arteries (usually of head and neck). Leads to blurred vision or sudden blindness, headaches, tender temporal artery. Emergency - high dose steroids
43
Name (3) the branches of V1
1) Frontal Nerve (i)Supraorbital nerve (ii) Supratrochlear nerve 2) Lacrimal Nerve 3) Nasociliary Nerve
44
What is Anisocoria? and name two types
Difference in pupil sizes 1) Adie pupil - parasymp defect = large atonic pupil 2) Horner's syndrome - symp defect = small pupil
45
What is sympathetic ophthalmitis?
v. rare complication of eye trauma. antigens exposed -> autoimmune reaction = can go blind
46
What is a hyphaema?
Bleeding between iris and cornea (i.e. anterior chamber)
47
What are the two types of macular degeneration?
Acute ("wet") macular degeneration - neovascular | Non-neovascular ("dry") - little impact on vision
48
What is the treatment for neovascular ("wet") macular degeneration?
Anti-VEGF (Ranibizumab (Lucentis))
49
What is Charles Bonnet Syndrome?
Visual hallucinations in people with macular degeneration
50
What is the process that occurs in Rods/Cones in the DARK?
GTP is converted to cGMP (by guanylate cyclase). | cGMP keeps Na+/Ca2+ channels open -> cell depolarised
51
What is the process that occurs in Rods/Cones in the LIGHT?
Photon hits Rhodopsin (11-cis retinal -> all-trans retinal) Opsin is activated -> activates phosphodiesterase cGMP->GMP = Ca/Na channel closes Na/Ca exchanger removes Ca -> membrane Hyperpolarised (less glutamate released)
52
How does the photoreceptor:bipolar cell ratio vary?
Periphery - many photoreceptors:bipolar cell | Centre - single photoreceptor:bipolar cell
53
What is used to assess colour vision defects?
Ishihara pseudoisochromatic plates
54
Name three photosensitive cells?
Rods Cones (three types - colour) Photosensitive retinal ganglion cell (regulation of diurnal rhythms)
55
What clinical feature will be present in retrobulbar neuritis (common in MS)?
Relative afferent pupillary defect
56
What are the differential diagnoses in a patient with light-near dissociation?
Dorsal midbrain syndrome -causes include pineal tumour, MS, brainstem infarction. (neurosyphilis)
57
What are the divisions of the Lateral Geniculate Nucleus?
6 laminae 1,2 = magnocellular (movement, temporal contrast) 3-6 = parvocellular (colour, spatial contrast) 1-6 = Koniocellular (blue-yellow contrast)
58
What does conjunctiva line?
Eyelid + anterior eyeball
59
What keeps the cornea transparent?
Ion pump in the endothelium keeps the collagen fibrils within the stroma in a state of dehydration
60
What happens in accommodation?
Pupil constriction (circular muscle (sphincter pupillae) contraction) Lens becomes more convex (contraction of muscles of ciliary body) Controlled by parasympathetic fibers (CN III) from the Edinger-Westphal nucleus
61
What does vitreous humour consist of?
99% water | Collagen fibrils & hyaluronan
62
What else can shingles on the end of the nose affect?
Nasociliary nerve - branch to eyeball also supplies tip/side of nose VZV infection can affect both
63
What kind of vision defect would a pituitary tumour cause?
Bitemporal hemianopia
64
What are the main causes of conjunctivitis?
Bacterial (e.g. chlamydia), Viral (Adenoviruses, HSV)
65
What are the main features of glaucoma?
Optic disc cupping ↑intraocular pressure ?Visual field loss
66
What is the most common type of glaucoma?
Acquired Primary Open Angle Glaucoma (POAG)
67
What are the treatments for glaucoma?
1) topical β-blockers (e.g. timolol) 2) carbonic anhydrase inhibitors (e.g. dorzolamide) 3) α-adrenergic agonist (e.g. apraclonidine) 4) parasympathomimetic (pilocarpine)
68
What are the main causes of Retinal Detachment?
Tractional - retina is pulled Exudative - caused by breakdown of the blood-retinal barrier, allowing fluid to accumulate in subretinal space Rhegmatogenous - caused by tear or hole