EYE Flashcards

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1
Q

What does ocular syphilis (STI) lead to?

A

Posterior uveitis & pan uveitis (vision changes, decreased visual acuity, permanent blindness)

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2
Q

What is morning glory syndrome?

A

A congenital defect of optic nerve, resembling “morning glory”

  • characterised by an enlarged, funnel-shaped cavity of optic disc
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3
Q

What is Leber congenital amaurosis?

A

Hereditary retinal degenerative disorder

  • abnormal dev of photoreceptors
  • optic nerve atrophy
  • poor vision at birth
  • photophobia, nystagmus (involuntary eye movements), extreme far-sightedness
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4
Q

What is optic nerve hypoplasia?

A

Congenital optic nerve underdevelopment (hypoplasia)

  • optic disc appears abnormally small because not all optic nerve axons have developed properly
  • may be associated with intracranial midline defect
  • can lead to hormonal imbalance + failure to thrive
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5
Q

What is optic disc drusen? (Fairly common!)

A

Optic nerve head malformation

- globules of mucoproteins & mucopolysaccharides that progressively calcify in optic disc

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6
Q

What is papilloedema?

A

Optic disc swelling caused by intracranial pressure

  • intracranial HTN due to tumour / cerebral venous sinus thrombosis / intracerebral haemorrhage / malignant HTN / optic neuritis / infiltration of optic nerve
  • swelling usually BILATERAL
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7
Q

What characteristics would we suspect poor vision in a child?

A
  • Nystagmus = involuntary, rapid, repetitive eye movement (often associated with reduced vision)
  • Generalised dev delay
  • Fam history of poor vision
  • Strabismus = misalignment of eyes [exotropia, esotropia = convergent,in]
  • Amblyopia (lazy eye) = functional reduction in visual acuity of an eye caused by disuse during visual dev
  • Leukocoria - white pupillary reflex
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8
Q

How do we manage amblyopia (lazy eye)?

A
  • Correct refractive error if indicated
  • patching (patch good eye to force bad eye to work)
  • atropine drops
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9
Q

What causes congenital ptosis?

A
  • ~3-5yo
  • Maldevelopment / dysgenesis of levator muscle
  • high risk for amblyopia
  • droopy lids
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10
Q

What is congenital Horner’s syndrome?

A

Abnormal sympathetic innervation to eye

  • common cause: birth trauma from brachial plexus injury
  • ptosis, miosis, anhidrosis on affected side
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11
Q

What are the symptoms of retinoblastoma? (Commonest primary ocular malignancy in children)

A

Leukocoria (white pupillary reflex)
Squint
Painful red eye

*sign: dilated fundoscopy - shows whitish-pink mass protruding from retina into vitreous cavity

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12
Q

What is the most common primary orbital malignancy in children?

A

Rhabdomyosarcoma (painful!)

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13
Q

What is dermoid cyst? Is it painful?

A

Dermoid cyst = common benign lesion in children

*Slow growing, painLESS

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14
Q

What is the difference between preseptal (aka periorbital) cellulitis and orbital cellulitis?

A

Periorbital cellulitis = infection in tissues around eye

Orbital cellulitis = infection of soft tissues within eye socket

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15
Q

What happens in orbital cellulitis?

A
  • decreased vision
  • pain on eye movements
  • proptosis (protrusion of eyeball)
  • pupil abnormality
  • raised WCC/ESR/CRP
  • Subperiosteal abscess

*think immunisation in kids! - Haem influenza, S.aureus, S. pneumonia

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16
Q

What is necrotizing fasciitis?

A

Necrosis of soft tissue

  • severe, sudden onset, rapidly progressive!
  • bacterial infection
  • treatment: prompt debridement + systemic antibiotics
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17
Q

What can cause ocular trauma?

A

Foreign body / retinal detachment / penetrating eye injury / eyelid laceration / orbital fracture / non-accidental eye injury

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18
Q

What happens to the eye when there’s infection due to Chlamydia trachomatis?

A

Trachoma - cause blindness by corneal scarring

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19
Q

What does Vitamin A deficiency lead to?

A

Blinding ocular disease (xerophthalmia)

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20
Q

What is hyphaema?

A

Blood in the front (anterior) chamber of eye

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21
Q

What is the Seidel test?

A

Used to assess presence of anterior chamber leakage in cornea

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22
Q

What characteristics might indicate anterior segment trauma?

A
  • hyphaema
  • corneal laceration
  • -Seidel sign —> would be positive when aqueous leaks from anterior chamber
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23
Q

What are the general principles of managing eye-related trauma?

A
  • assess extent of injury
  • protection from further injury
  • avoid removing foreign body where possible
  • antibiotics
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24
Q

What is madarosis?

A

Loss of lashes

- can be caused by bacterial / fungal / viral infections

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25
Q

What is retrobulbar haemorrhage?

A

Uncommon, vision-threatening complication of orbital + eyelid surgery

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26
Q

What increases risk of retrobulbar haemorrhage?

A

Use of anticoagulant meds, vascular disease, HTN & early exertion / straining after orbital + eyelid surgery

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27
Q

What’s the definitive treatment of vision-threatening retrobulbar haemorrhage?

A

Emergent surgical intervention to decompress the orbit

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28
Q

What are the signs of retrobulbar haemorrhage?

A

Pain (severe), pressure, loss of vision (may be accompanied by visual flashes + amaurosis fugax), diplopia, nausea/ vomiting

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29
Q

What are the factors of severe dry eye?

A

Ageing, meds, autoimmune (Sjogren), conjunctival inflammation

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30
Q

Why would severe dry eye cause increased risk of infection?

A

Loss of barrier + immune functions

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31
Q

How to increase amount of available tears on surface of eye?

A

Increasing moisture of eye (use eye drops), use muscarinic agonist - to increase tear production, prevent drainage (put plugs in punctum to block off drainage)

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32
Q

Why do we need intact epithelium in eye?

A

Essential for protection! Loss of barrier function = high risk of opportunistic infection

*trauma, infection, degenerative disease —> breakdown in epithelial layer

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33
Q

What causes corneal opacity?

A

Trauma, infection, inflammation —> scar —> loss of corneal clarity

*Herpes zoster, CMV, HSV I & II —> these can cause eye condition that cause corneal opacity

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34
Q

Endothelium regulates clarity by?

A

Controlling hydration!

  • Endothelium can be damaged by:
  • local trauma / surgical trauma
  • infection e.g. herpes viruses
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35
Q

What is keratotonus? What happens?

A

Common corneal dystrophy

  • progressive thinning of cornea —> weakness —> cornea bulges out & shape changes —> loses ability to focus nicely
  • caused by ocular allergies
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36
Q

Why do the eyes lose ability to focus nicely in keratotonus?

A

Due to progressive thinning of cornea —> weakness —> cornea bulges out & shape change

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37
Q

Why can’t we use glasses to deal with keratotonus?

A

Because the cornea has irregular shape!

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38
Q

What are the treatment for ocular allergy?

A

Steroids

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39
Q

What are defocus diseases?

A

Due to imbalance between focusing lenses of eye + size / shape of eye

*eye might be too long / short

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40
Q

What are the factors for cataract?

A
  • Age
  • Diabetes
  • Meds esp. steroids!
  • Trauma
  • Infection
  • Genetic
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41
Q

What are the symptoms of cataract?

A

Reduced visual acuity - blurred, clouded, dim vision esp at night
Painless visual impairment, often bilateral
Glare - associated with halos around light

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42
Q

What is cataract? What is the complication of cataract?

A

Clouding of the lens of eye

Complication - blindness!

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43
Q

What is pterygium (aka eye web)?

A

A growth of conjunctiva / mucous membrane that covers white part of eye over cornea

  • develops when eye is regularly exposed to bright sunlight + wind
  • can cause discomfort + blurry vision
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44
Q

What are the 4 tests for RED EYE?

A
  • Visual acuity
  • Flurescein - epithelial defect, Seidel’s sign
  • Cells & flare
  • Intraocular pressure
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45
Q

What is a rare, severe, infection of the eye that’s usually post operative? (Starts with ‘e’)

A

Endophthalmitis
= inflammation of interior of the eye

  • possible complication of ALL intraocular surgeries esp cataract surgery, with possible loss of vision & the eye itself
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46
Q

What is excessive watering of the eye known as?

A

Epiphora

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47
Q

What happens to the eye in glaucoma?

A

Damage to optic nerve (optic neuropathy) by the effects of increased ocular pressure

Axon loss —> visual field defects + loss of visual acuity if central visual field involved

48
Q

Glaucoma results in central or peripheral visual loss?

A

Peripheral visual loss

49
Q

What is the chief modifiable risk factor for glaucoma?

A

Intraocular pressure!

*practically glaucoma is outflow problem!

50
Q

Why is acute glaucoma a med emergency?

A

Pressure may exceed arteriolar perfusion pressure —> ischaemia!

51
Q

If someone comes to you presenting with eye pain, which parts of the eye would you suspect to be involved?

A

External layers of the eye - cornea, conjunctiva (sharp, gritty, burning)

  • Pain can ONLY arise from external layers of eye!
  • Retina & lens - asensate!
52
Q

When one presents with scotoma, what would you suspect?

A

Must be in retina / optic nerve!

*Macular degeneration can present with scotoma!

53
Q

Floaters ONLY occur in?

A

Vitreous cavity!

*so if patient says there’s floaters you know it’s something relating to vitreous cavity!

54
Q

What can cause RAPD?

A

Ischemic optic neuropathy, optic neuritis, optic nerve compression, trauma

55
Q

What are some examples of optic nerve disease?

A
  • Glaucoma (most common)
  • anterior ischemic optic neuropathy - giant cell arteritis
  • optic neuritis
56
Q

If an elderly patient comes to you presenting with unilateral headache, NO pain on eye movement, jaw pain, scalp tenderness, loss of appetite, transient visual loss, what would be your top differential diagnosis?

A

Giant cell arteritis.!

57
Q

What is the difference between giant cell arteritis and optic neuritis when it comes to eye movement?

A

Giant cell arteritis - no pain on eye movement

Optic neuritis - pain on eye movement

58
Q

Describe optic neuritis

A

Acute visual loss, can have pain on eye movement, associated with MS

  • RAPD,
  • may have nerve swelling
  • decreased colour vision
59
Q

What is the function of retinal pigment epithelium (RPE)?

A

*Vital to normal function of neural retina!!

  • outer retinal blood barrier
  • storage of metabolites + Vit A
  • nutrient supply to photoreceptors
  • phagocytosis of photoreceptors discs

**With age: oxidative stress to RPE —> alteration in Bruce’s membrane permeability —> Drusen

60
Q

What are the risk factors for age-related macular degeneration (AMD)?

A
  • age
  • smoking
  • gender (F>M)
  • CVS risk
  • white Caucasian
61
Q

What are the signs and symptoms of age-related macular degeneration (AMD)?

A

Symptoms:

  • central vision reduction
  • distorted vision
  • SCOTOMA (dry - gradual; wet - acute)
  • scotoma = loss of CENTRAL visual field

Signs:

  • foveal reflex absent
  • yellow, well-circumscribed drusen present
62
Q

What are the pathogenesis of AMD (age-related macular degeneration)?

A

RPE (retinal pigment epithelium) removes & processes the used discs of photoreceptors outer segments —> over time, undigested lipid products accumulate in RPE + excess material is transferred to Bruch’s membrane —> impairing its diffusion all properties

*Extracellular deposits form between RPE & Bruch’s membrane - can be seen with ophthalmoscope as discrete, sub-retinal yellow lesion called DRUSEN

63
Q

What is the difference between dry and wet AMD?

A

Wet = bleeding!

64
Q

What happens in wet AMD (age related macular degeneration)?

A

New vessels from choroid (stimulated by angiogenic factors e.g. VEGF) grow thru Bruch’s membrane & RPE into sub-retinal space —> form sub-retinal neovascular membrane

65
Q

What drugs can we use for wet AMD?

A

Intravitreal anti-VEGFs (inhibit action of angiogenic factors - retard angiogenesis + cause regression of existing new vessels)

66
Q

What happens in posterior vitreous detachment?

A

= vitreous membrane (posterior hyaloid membrane) separates from retina

Symptoms: floaters, flashes, curtain type field defect, reduced central vision (macula involvement)

Signs: vitreous haemorrhage

67
Q

What is retinal detachment?

A
  • EMERGENCY!
  • retina pulls away from supportive tissue (that provide O2 + nourishment)
  • floaters, flashing, curtain field defect
68
Q

In malignant HTN, very high may cause ___?

A

Swelling of optic nerve head

69
Q

What are the risk factors of retinal vein occlusion?

A
  • Age
  • HTN
  • DM
  • Smoking
  • Obesity
  • pro-thrombotic / hyper-viscosity state e.g. pregnancy
  • abnormality of venous wall (inflammation)
  • increased ocular pressure
70
Q

How many different grades are there for HTN retinopathy?

A

Grade 1 - mild generalised retinal arteriolar narrowing

Grade 2 - focal arteriolar narrowing, AV nick, copper wiring

Grade 3 - Grade 2 + retinal haemorrhage (dot, blot, flame), exudates

Grade 4 - Grade 3 + disc swelling (malignant HTN)

71
Q

What are the signs and symptoms of retinal vein occlusion?

A
  • Sudden partial / complete loss of vision

Signs:

  • marked retinal haemorrhage
  • swelling of veins
  • OPTIC DISC ENGORGED + SWOLLEN
  • In an ischemic retinal vein occlusion, where retinal ischaemia is extensive:
  • Abnormal new vessels may grow onto retina + optic disc —> vitreous haemorrhage
  • new vessels may grow into iris —> neovascular glaucoma
72
Q

What happens in retinal arterial occlusion?

A
  • Ocular emergency!
    Fibrin-platelet emboli —> typically cause a fleeting loss of vision as the emboli pass thru the retinal circulation (amaurosis fugax)

*Cholesterol / calcific emboli —> may result in permanent obstruction with no recovery in vision!

73
Q

What are the clinical features of retinal arterial occlusion?

A
  • SUDDEN PAINLESS unilateral vision loss, amaurosis fugax
  • RAPD
  • white swollen retina (oedematous) with CHERRY-RED SPOT AT MACULA
  • after a few weeks, disc becomes atrophic + white, arterioles attenuated & cattle-trucking (segmentation of blood column in arteries)
74
Q

Does someone with retinal arterial occlusion present with pain?

A

NO. SUDDEN PAINLESS UNILATERAL vision loss!

75
Q

What is ocular ischemic syndrome?

A

Hypoperfusion from severe carotid artery obstruction

76
Q

What are the terms for inflammation of iris, inflammation of ciliary body, inflammation of choroid?

A

Inflammation of iris = anterior uveitis (iritis)
Inflammation of ciliary body = intermediate uveitis
Inflammation of choroid = posterior uveitis (choroiditis)

77
Q

What are the signs of intraocular inflammation?

A
  • cells + flare in anterior chamber
  • HYPOPYON (inflammatory cells in anterior chamber of eye. Exudate rich in WBC + redness of conjunctiva)
  • posterior synechiae (iris is adherent to anterior lens capsule)
  • keratic precipitates (inflammatory cellular deposit seen on corneal epithelium)
78
Q

50% of unilateral anterior uveitis is related to which systemic disease?

A

HLA b27 spondyloarthropathies

79
Q

What are the signs and symptoms for anterior uveitis related to HLA B27 spondyloarthropathies?

A
  • pain, photophobia
  • ciliary injection (redness maximal around limbus)
  • anterior chamber cells + flare
  • keratic precipitates (inflammatory cellular deposit seen on corneal epithelium)
  • posterior synechiae
  • reduced IOP
  • macular oedema

Treatment: topical steroids

80
Q

What are the signs of juvenile idiopathic arthritis related uveitis?

A
  • cells + flare in anterior chamber
  • posterior synechiae
  • cataract
  • band keratopathy (Ca deposits across surface of cornea)
  • macular oedema (if inflammation is bad)
81
Q

What are the ocular complications of juvenile idiopathic arthritis?

A
  • Amblyopia (lazy eye)
  • cataract (common complication of uveitis)
  • band keratopathy (ca deposit in anterior cornea)
  • glaucoma
  • chronic macular oedema
  • hypotony (IOP 5mmHg or less) : worst complication!!
82
Q

What eye disease can occur in RA? (Systemic disease)

A

Scleritis! (V.serious!)

  • serious inflammatory disease that affects sclera
83
Q

What is scleromalacia perforans?

A

Necrotizing scleritis!

  • most severe form of scleritis!
  • sometimes leading to loss of eye
  • a serious eye condition that can result in loss of vision
  • thinning of sclera to the point you can see choroid (v. Thin —> increase risk of globe rupture)

*often associated with systemic disease

84
Q

What eye condition can present in sarcoidosis?

A

BILATERAL anterior uveitis

85
Q

What eye conditions can we manage using methotrexate ?

A

Uveitis due to Juvenile idiopathic arthritis, bilateral anterior uveitis due to sarcoidosis

86
Q

What is Behçet’s disease?

A
  • rare disorder causing inflammation in BV

- eye symptoms: HYPOPYON in anterior chamber

87
Q

What is pars planitis?

A

Common form of uveitis in young adolescent

88
Q

What is Vogt-Koyanagi-Harada disease?

A
  • common cause of uveitis in Japan
  • rare granulomatous inflammatory disease that affects pigmented struc e.g. eyes, ears
  • headache, meningiomas, fever, tinnitus, hearing loss
  • severe POSTERIOR UVEITIS with serious RETINAL DETACHMENTS
89
Q

What is the treatment for primary open-angle glaucoma?

A

Prostaglandins analogues - increase aqueous passage

90
Q

What are the symptoms of primary closed-angle glaucoma?

A

Photophobia, very pain due to ischemic tissue damage, experience halos (coloured) around bright lights

91
Q

What are the causes of primary open-angle / closed-angle glaucoma?

A

Open-angle : obstruction due to STRUCTURAL CHANGES in trabecular mesh work

Closed-angle : peripheral iris blocks mesh work

92
Q

What are the treatment options for primary closed-angle glaucoma?

A

Acetazolamide + topical pilocarpine + B-blockers

Acetazolamde + B-blockers —> decrease aqueous secretion + pressure gradient across iris

Topical pilocarpine —> constricts pupil + draws peripheral iris out of the angle

93
Q

What are the functions of fluorescein eye stain?

A

A test that uses orange dye (fluorescein) + blue light to detect foreign bodies in the eye!

Can also detect damage to cornea!

94
Q

What is keratitis?

A

Inflammation of cornea

95
Q

When a patient presents with unilateral red eye, painless, no discharge, and on eye examination you see a bright red patch with clear borders. What is the most likely condition?

A

Subconjunctival haemorrhage

  • a bright red patch appearing in the conjunctiva
  • bleeding underneath conjunctiva
96
Q

In the event of facial nerve palsy, what intrinsic mechanism may protect cornea in the majority of patients as they attempt to close the affected eye ?

A

Bell’s phenomenon

- upward + outward movement of eye when an attempt is made to close the eyes

97
Q

How do you manage a potential ruptured globe?

A

Attach an eye shield! Not an eye pad / antibiotics / anaesthetic!

98
Q

What clinical findings are associated with diabetic eye disease?

A
  • COTTON WOOL SPOTS
  • macular oedema
  • neovascularisation
  • retinal haemorrhages
99
Q

What are the findings in severe hypertensive retinopathy?

A

Disc swelling + retinal haemorrhages

100
Q

What clinical findings are associate with DRY age-related macular degeneration?

A
  • central scotoma
  • drusen
  • RPE atrophy

**NO HAEMORRHAGE - that’s wet AMD!

101
Q

What bio-physical forces are likely to be involved in pathophysiology of rhegmatogenous retinal detachment?

A
  • vitreous fluid currents push fluid into sub-retinal space
  • vitreous remains attached to anterior edge of retinal tear
  • vitreous traction opens hole / break in retina
  • sub-retinal fluid migrates inferiorly under gravity
102
Q

Is RAPD found in cataract?

A

NO.

103
Q

The ligamentous sling thru which superior oblique muscle of eye passes thru is known as?

A

Trochlea

104
Q

What are the causes of painLESS red eye?

A

Subconjunctival haemorrhage
Blepharitis
Conjunctivitis
Episcleritis

105
Q

What are the causes of painFUL red eye?

A
Scleritis
Corneal ulcer
Corneal abrasion 
Uveitis 
Viral keratitis 
Acute angle closure glaucoma 
Endophthalmitis 
Foreign body 
Chemical injury
106
Q

Posterior synechia is adhesion between which 2 structures?

A

Iris and lens.

107
Q

What are features of anterior uveitis (iritis)?

A

Hypopyon (pus)
Photophobia
Reduced visual acuity

108
Q

Between which 2 structures does optic tract run?

A

Lateral geniculate nucleus and optic chiasm

109
Q

What would oculomotor nerve palsy result in?

A

Eye moves down and out + pupillary dilation

110
Q

What are the differences between vitreous chamber, and anterior / posterior chambers?

A

Vitreous chamber - contains vitreous fluid

Posterior / anterior chamber - contains aqueous fluid

111
Q

Homonymous hemianopia is due to lesion at:

A

Optic tract

112
Q

Which cranial nerve innervates muscles that raise upper eyelid?

A

Oculomotor nerve

Levator palpebrae superioris

113
Q

Describe the flow of aqueous humour.

A

Produced by epithelium of ciliary body –> posterior chamber –> flows thru pupil –> anterior chamber –> drained into canal of Schlemm

114
Q

The radial muscles of iris are innervated by __ nervous system and their contraction causes pupillary __

A

Sympathetic, dilation

115
Q

What happens to iris muscles in dim / bright room?

A

Dim: iris RADIAL MUSCLE contracts –> pupil dilation

Bright: iris CIRCULAR MUSCLE contracts –> pupil contraction