ophthalmology Flashcards
rash in trigeminal distribution on right
herpes zoster opthalmicus. oral antivirals, maybe topical steroid, ocular involvement see ophthalm
Hutchinson’s sign: vesicles extending to the tip of the nose. This is strongly associated with ocular involvement in shingles
horners syndrome
miosis (small pupil)
ptosis
enophthalmos* (sunken eye)
anhidrosis (loss of sweating one side)
can be caused by pancoasts tumour (apical lung- can cause pain)
vitreous haemorrhage risk factors
Diabetes Trauma Anticoagulants Coagulation disorders Severe short sightedness
presents with sudden vision loss and dark spots
scleritis
features red eye painful (episcleritis is not) watering and photophobia gradual decrease in vision
types of stye
external (hordeolum externum): infection (usually staphylococcal) of the glands of Zeis (sebum producing) or glands of Moll (sweat glands).
internal (hordeolum internum): infection of the Meibomian glands. May leave a residual chalazion (Meibomian cyst)
argyll roberston pupil
prostitutes pupil- neurosyphillis
no response to light but constriction on accomodation
herpes simplex keratitis
red, painful eye photophobia epiphora visual acuity may be decreased fluorescein staining may show a dendritic epithelial ulcer
HLA B27
anterior uveitis
cheese and tomato pizza
central retinal vein occlusion
Tx for anterior uveitis
Anterior uveitis is most likely to be treated with a steroid + cycloplegic (mydriatic) drops
wet vs dry age related macular degeneration
dry (90% of cases, geographic atrophy) macular degeneration: characterised by drusen - yellow round spots in Bruch’s membrane
wet (10% of cases, exudative, neovascular) macular degeneration: characterised by choroidal neovascularisation. Leakage of serous fluid and blood can subsequently result in a rapid loss of vision. Carries worst prognosis
Holmes-Adie pupil
unilateral in 80% of cases
dilated pupil
once the pupil has constricted it remains small for an abnormally long time
slowly reactive to accommodation but very poorly (if at all) to light
Holmes-Adie syndrome
association of Holmes-Adie pupil with absent ankle/knee reflexes
central retinal artery occlusion
causes sudden unilateral visual loss
due to thromboembolism (from atherosclerosis) or arteritis (e.g. temporal arteritis)
features include afferent pupillary defect, ‘cherry red’ spot on a pale retina
Tunnel vision
causes
papilloedema glaucoma retinitis pigmentosa choroidoretinitis optic atrophy secondary to tabes dorsalis
types of glaucoma associate with which vision changes
acute angle closure- hypermetropia
primary open angle- myopia
acetazolamide
carbonic anhydrase inhibitor
screening for glaucoma
yearly if family history of primary open angle glaucoma from age 40
stages of hypertensive retinopathy
I Arteriolar narrowing and tortuosity Increased light reflex - silver wiring II Arteriovenous nipping III Cotton-wool exudates and blot haemorrhages IV Papilloedema
glaucoma medication
Medication Mode of action Notes Prostaglandin analogues (e.g. latanoprost) Increases uveoscleral outflow Once daily administration
Adverse effects include brown pigmentation of the iris, increased eyelash length
Beta-blockers (e.g. timolol, betaxolol) Reduces aqueous production Should be avoided in asthmatics and patients with heart block
Sympathomimetics (e.g. brimonidine, an alpha2-adrenoceptor agonist) Reduces aqueous production and increases outflow Avoid if taking MAOI or tricyclic antidepressants
Adverse effects include hyperaemia
Carbonic anhydrase inhibitors (e.g. Dorzolamide) Reduces aqueous production Systemic absorption may cause sulphonamide-like reactions
Miotics (e.g. pilocarpine, a muscarinic receptor agonist) Increases uveoscleral outflow Adverse effects included a constricted pupil, headache and blurred vision
glaucoma guidelines
first line: prostaglandin analogue (PGA) eyedrop
second line: beta-blocker, carbonic anhydrase inhibitor, or sympathomimetic eyedrop
if more advanced: surgery or laser treatment can be tried2
Periorbital (preseptal) vs Orbital cellulitis
Absence of painful movements, diplopia and visual impairment indicates the former
squint features
Concomitant
Due to imbalance in extraocular muscles
Convergent is more common than divergent
Paralytic
Due to paralysis of extraocular muscles
squint names
the nose: esotropia
temporally: exotropia
superiorly: hypertropia
inferiorly: hypotropia
management of ARMD
fluorescein angiography is utilised if neovascular ARMD is suspected, as this can guide intervention with anti-VEGF therapy. This may be complemented with indocyanine green angiography to visualise any changes in the choroidal circulation.
zin +vit acd
laser photocoag
types of diabetic retinopathy
Mild NPDR
1 or more microaneurysm
Moderate NPDR microaneurysms blot haemorrhages hard exudates cotton wool spots, venous beading/looping and intraretinal microvascular abnormalities (IRMA) less severe than in severe NPDR
Severe NPDR
blot haemorrhages and microaneurysms in 4 quadrants
venous beading in at least 2 quadrants
IRMA in at least 1 quadrant
night blindness and tunnel vision
retinitis pigmentosa fundoscopy: black bone spicule-shaped pigmentation in the peripheral retina, mottling of the retinal pigment epithelium
causes of cataracts
Smoking Increased alcohol consumption Trauma Diabetes mellitus Long-term corticosteroids Radiation exposure Myotonic dystrophy Metabolic disorders: hypocalcaemia
causes of papilloedema
space-occupying lesion: neoplastic, vascular malignant hypertension idiopathic intracranial hypertension hydrocephalus hypercapnia
retinal artery occlusion
due to thromboembolism or arteritis
features include afferent pupillary defect, ‘cherry red’ spot on a pale retina
