Opthalmology Flashcards
What is the examination sequence for the eyes?
Inspection, then AFRO: Acuity (snellen, close reading, colour), Fields (inattention, confrontation, offer blind spot), Reflexes (accommodation, direct, consensual, RAPD), Ophthalmoscopy and ophthalmoplegia (optic disk - cup, colour and contour; four quadrants; macula; H-test for eye movements +/- saccade test +/- ask them to look upwards and count to 20 to check for fatigueability)
What is the commonest cause of irreversible loss of vision?
AMD
What are the differentials for painless loss of vision?
1) Open angle glaucoma 2) AMD 3) retinal vessel occlusion 4) retinal or vitreous haemorrhage 5) diabetic/hypertensive retinopathy 6) optic neuritis 7) cataracts 8) ischaemic optic neuropathy 9) ethambutol
What are the differentials for gradual loss of vision?
1) cataracts 2) corneal opacification 3) AMD 4) Diabetic or hypertensive retinopathy 5) retinitis pigmentosum 6) glaucoma 7) optic neuropathy
What are the main risk factors for AMD?
Age, DM, HTN, Caucasian race, smoking, male
What are the main findings in wet AMD?
Dry AMD findings + neovascularisation, haemorrhages + disciform scarring
What are the typical findings in dry AMD?
Drusen, geographic atrophy, pigmentation changes in the RPE
What investigations are indicated in someone with suspected AMD?
Slit-lamp + OCT +/- fluorescein angiography (if early wet suspected)
What is the pathophysiology of AMD?
RPE fails to clear lipid waste from rods and cones. These build up and pass through Bruch’s membrane and form deposits. Local ischaemia leads to neovascularisation
What treatments are available for AMD?
Lifestyle modification, vitamins and minerals, anti-VEGF injections
What is an example of an anti-VEGF injection?
Ranibizumab
What is the first line treatment for open angle glaucoma and what is it’s mechanism of action?
Latanoprost - increases uveoscleral outflow
What are the risk factors for open angle glaucoma?
IOP, Afro-Carribean, myopia, thin central cornea, family history
What are the classic examination findings in glaucoma?
Nasal steps, arcuate field loss, optic disc cupping
What is the immediate management of acute angle closure glaucoma?
All topical medication not contraindicated - can include topical beta-blockers, pilocarpine. Also give oral or IV acetozolamide.
What are the risk factors for angle-closure glaucoma?
Hypermetropia, Asian, Female, Family history, increasing age (lens thickness increases)
What investigations should be done for suspected myaesthenia gravis?
CT/MRI head Edrephonium test (cholinesterase drops) Anti-cholinesterase auto antibodies
What are the symptoms of cavernous sinus thrombosis?
Recent facial infection Ophthalmoplegia Ptosis Peri-orbital oedema Headache
What is leukocornia?
White pupil - can indicate congenital cataracts or retinoblastoma. Both are serious and need investigation and rapid treatment.
What is retinopathy of prematurity and how is it treated?
High O2 levels after birth decreases VEGF, leading to poor formation of retinal blood vessels. Laser photocoagulation needed to prevent retinal haemorrhage or vitreous detachment
What causes are there for congenital cataracts?
Inherited - congenital
Viral - rubella, CMV, Varicella
Genetic - Edward’s or Down’s
What are the DVLA eye requirements?
At least one eye with 6/12 and 120 degrees of vision
What characterises the pre-proliferative stages of diabetic retinopathy?
Mild - more than 1 microaneurysm
Moderate - haemorrhages, microaneurysms, lipid exudate, venous beading, IRMAs
Sever - Haemorrhages or microaneurysms in all 4 quadrants, or venous beading in 2 or more quadrants, + IRMA in at least 1 quadrant
What are the two stages of proliferative diabetic retinopathy?
Early - new vessels on retinal
High risk - new vessels and haemorrhage or new vessels >1/4 of the disc.
