Opthalmology Flashcards
What do you need to do for opthalmoscopy ?
dilate pupil by relaxing sphincter muscles
-Eg Atropine
[Tropicamide /
Cyclopentolate ]
Things to describe in the optic disk
Colour
Contour
Cup
Circulation
Name 3 causes of retinal haem
diabetic retinopathy, SAH, vasalva haemorrhage, hypertensive retinopathy,
What would a bright yellow ring around a central leak in opthamoscopy indicate ? mx if near macula?
fluid leakage
laser
What are cotton wool spots -
micro infarcts
What are drusen?
pale, round and grey. Seen at the macula in the elderly
-> sign of age-related macula degeneration
spidery black pigmentation in peripheral retina?
Retinitis pigmentosa
-inherited retinal degeneration
What is a scotoma
Cause of a central?
blind spot
lesion in the optic nerve between nerve head and chiasm
-Eg optic neuritis, MS
Macular degeneration leads to a central scotoma
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What is meant by congruity?
refers to the agreement of shape of the defect.
The closer to the visual cortex - the more congruous
What is a junctional scotoma
Lesion at junction of optic nerve and chiasm
->contralateral nasal fibres compressed because the nasal fibres dip into the optic nerve before travelling down the optic tract.
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What is a slit lamp used for
examining the anterior segment of the eye (i.e. infront of the vitreous body)
Small depression in centre of macula
fovea
Central/thickest part of retina, high concentration of cones
macula
Central retina, colour vision and acuity
Cones
Outer retina, night vision
rods
Highly pigmented and vascular layer below RPE, provides O2 req of outer retina
Choroid
How can you test acuity
snellen chart
What is a cataract
Any opacity or clouding of the lens, progressive over years, usually bilat
Name 3 rfs of cataract
Sunlight, age, smoking, alcohol, corticosteroid, DM
What is meant by ‘the angle’ in open angle glaucoma
Space between posterior surface of cornea and anterior surface of iris.
Where the aqueous humour leaves the eye.
Where is aqueous humour produced?
what does it do?
Ciliary body, circulates and nourishes lens.
What is chronic open angle glaucoma? (its the most common)
O/E?
Chronic, progressive, optic neuropathy with characteristic changes in optic nerve head and corresponding visual field loss
3 THINGS:
- enlargement of optic disc cup (loss of neurones)
- Progressive visual field loss -> tunnel vision
- raised intraocular pressure (>21) - however this is not always present because some people can have normal pressure glaucoma
Triad of glaucoma
Raised IOP (>21mmHg) - not always present
Abnormal disc - cup:disc ratio - (cup gets bigger ) asymmetry, disc haemorrhage etc
VF defect - tunnel vision
3 Ix in screening of chronic open angle glaucoma
IOP - low specificity, high FPR
VF test - high FPR
Fundoscopy - cupping - high FPR