Opthalmology Flashcards
What is Blepharitis?
Inflammation of the rims of eyelids
Aetiology of Blepharitis
Chronic staphylococcal infection + Meibomian gland dysfunction
Presentation of Blepharitis
Gradual onset gritty/dry eye, crusting on lashes, red conjunctivae, red rimmed thickened lid margins, blocked/oozing Meibomian glands
Management of Blepharitis
Eyelid hygiene, massage, hot compresses
Topical Chloramphenicol
What is a Chalazion?
Granuloma of Meibomian gland
Presentation of Chalazion
Eyelid swellng/lump, tender red eye, watery eye, heaviness of eyelid
Management of Chalazion
Warm compresses, Chloramphenicol, Surgical incision
What is a stye?
Infection of the lash follicle
What is the most common tumour of the eyelid?
Basal Cell Carcinoma
Which muscles does the 3rd cranial nerve (oculomotor) supply?
Levator palpebrae superioris, Superior rectus, Inferior rectus, Medial rectus, Inferior oblique Constrictor pupillae (constricts pupil) Ciliary muscles (adapts to short range vision)
Causes of 3rd nerve palsy
Raised ICP- compressed against temporal bone
Posterior communicating artery aneurysm, Cavernous sinus infection/trauma, Diabetes, MS, MG
Presentation of 3rd nerve palsy
Ptosis, eye down & out, unable to elevate, depress or adduct eye, fixed dilated pupil
Management of 3rd nerve palsy
Treat the cause
Aetiology of Retinal Tear/Detachment
Neurosensory layer detaches from epithelium
Most preceded by posterior vitreous detachment
Risk factors for Retinal Tear/Detachment
Myopia, FH, previous Hx, age, lattice degeneration, Marfan’s, diabetic retinopathy, maculopathy
Presentation of Retinal Tear/Detachment
New onset floaters/flashes, sudden onset painless progressive visual loss, RAPD, altered red reflex
Management of Retinal Tear/Detachment
Urgent referral
Cryotherapy/Photocoagulation for tears
Surgery for detachment
Topical Abx + steroids
Aetiology of Diabetic Retinopathy
Microvascular occlusion –> Retinal ischaaemia –> Arteriovenous shunts + neovascularisation
Leakage –> intraretinal haemorrhages + oedema
Visual loss due to macular oedema, foveal ischaemia and foveal haemorrhage
Presentation of Diabetic Retinopathy
Gradual reduction in central vision
Haemorrhages cause sudden onset dark painless floaters
Features of Background Diabetic Retinopathy
Microaneurysms, Blot haemorrhages, Hard exudates
Features of Pre-proliferative Diabetic Retinopathy
Cotton wool spots, >3 blot haemorrhages, venous beading/looping, dark cluster haemorrhages
Features of Mild vs Moderate vs Severe Non-proliferative Diabetic Retinopathy
Mild: 1 or more microaneurysms
Moderate: microaneurysms, blot haemorrhages, hard exudates, cotton wool spots, venous beading/looping
Severe: blot haemorrhage + microaneurysms in 4 quadrant, venous beading in at least 2 quadrants, intraretinal microvascular abnormalities in 1 quadrant
Features of Proliferative Diabetic Retinopathy
Retinal neovascularisation, fibrous tissue forming anterior to retinal disc
How often are diabetics screened for Diabetic Retinopathy?
Annually
Management of Diabetic Retinopathy
Glycaemic + BP control
Smoking cessation
Laser treatment, intravitreal steroids, anti-VEGF, vitrectomy for bleed
What is Diabetic maculopathy?
Grouped exudate within the macula
Any exudate or retinal thickening within 1 disc diameter of the foveola
Management of diabetic maculopathy
Laser
Intravitreal triamcinolone
What is the arterial supply to the eye?
Opthalmic artery from internal carotid
What s the venous supply of the eye?
Superior and inferior opthalmic veins- drain into cavernous sinus
Differentials of a red eye
Keratitis Scleritis Uveitis Endopthalmitis Acute glaucoma
Causes of blue sclera
Rheumatoid arthritis
Marfan’s syndrome
Causes of proptosis/exopthalmos
Eye forwards- thyroid disease
Eye downwards- lacrimal gland tumour
Causes of purulent eye discharge
Infection, allergy
Causes of bloody eye discharge
Severe infection
Tumour
Cause of sudden visual loss
Vascular/inflammatory eg retinal vein occlusion
Causes of transient visual loss
Vascular cause- GCA/retinal emboli
Causes of central visual loss
Macular or optic nerve disease
Causes of peripheral visual loss
Glaucoma, CVA, retinitis pigmentosa
Causes of colour vision loss
Optic neuritis, cataract, drug toxicity
Cause of poor night vision
Retinitis pigmentosa
Causes of loss of red reflex
Cataracts, Retinoblastoma
What is Amaurosis fugax?
Transient and painless loss of vision in one eye - transient retinal ischaemia
What are the most common causative organisms for infectious conjunctivitis?
Adenovirus, Herpes, Staph, Strep, Moraxella, Chlamydia, Gonorrhoea
Management of infectious conjunctivitis
Topical antibiotics- Chloramphenicol
What are red flags of a red eye?
Impaired vision, pain/photophobia, lack of ocular discharge
What is uveitis?
Inflammation of the uveal tract (iris + ciliary body + choroid)
Anterior (iritis) or Posterior
Causes of Uveitis
Autoimmune disease eg Sarcoidosis, infections, infiltrative (neoplastic), trauma, ischaemic, immunosuppression
How do you determine if Uveitis is granulomatous or not?
Whether or not there are keratic precipitates
Presentation of Anterior Uveitis
Unilateral painful red eye, photophobia, pain worse when reading, blurred vision, tear production, headache
Presentation of Intermediate Uveitis
Painless floaters, reduced vision
Presentation of Posterior Uveitis
Gradual visual loss, bilateral blurred vision and floaters
Management of Uveitis
Cytoplegic-mydriatic drugs- 1% Atropine- relieves pain and prevents adhesions Corticosteroids Immunosuppressors- Ciclosporin Laser phototherapy, Cryotherapy Vitrectomy
What is Glaucoma?
Damage to the optic nerve head with progressive loss of retinal ganglion cells and their axons
Aetiology of open angle glaucoma
Flow is reduced through trabecular meshwork (absorbs aqueous humour) –> painless chronic degenerative obstruction
Aetiology of closed angle glaucoma
Iridocorneal angle closed by forward displacement of the foot of iris against the cornea –> aqueous humour cannot flow from posterior to anterior angle –> rapid and painful build up
Risk factors for Glaucoma
Raised IOP, myopia, diabetes, FH, Female, prolonged steroid use, uveitis, hypertension, trauma
Mydriatic drops can be a precipitant of closed-angle
Investigation in Glaucoma
Gonioscopy- measure angle between cornea + iris
How is Glaucoma screened for?
Annual screening from age 40 if family history
Presentation of open-angle glaucoma
Majority asymptomatic
Chronic progressive bilateral peripheral visual loss then tunnel vision
Intraocular pressure 11-21
Management of Glaucoma
- Increase uveoscleral outflow- Prostaglandin analogues- Latanoprost
- Reduce aqueous production- B Blockers- Timolol
- Trabeculectomy/Laser surgery
DVLA!
Presentation of closed-angle glaucoma
Severe and rapid pain, blurred vision, coloured haloes, N&V, red eye
Hard globe- raised IOP
What is the world’s leading cause of blindness?
Cataracts
Risk factors for cataracts
Age, smoking, diabetes mellitus, systemic corticosteroids, uveitis, UV exposure, malnutrition
Paeds: Rubella, metabolic, trauma
Presentation of cararacts
Gradual painless loss of vision, diplopia, glare, haloes, defects in red reflex
Management of cataracts
Surgery- lens extraction + replacement
Phacoemulsification
DVLA
What is Age-related Macular Degeneration?
Ageing changes without any other obvious precipitating cause in the macula age > 55
Risk factors for Age-related Macular Degeneration
Smoking, age, FH, hypertension, aspirin use, exposure to sunlight, previous cataract surgery, alcohol, obesity, hyperopia, CV disease
Pathophysiology of Age-related Macular Degeneration
Dry- Drusen- collection of lipid + proteins beneath retinal pigment epithelium + within Bruck’s membrane
Atrophy of light-sensitive cells, neovascular AMD
Presentation of Age-related Macular Degeneration
Can be asymptomatic
Painless deterioration and blurring of central vision
Metamorphosia- straight lines blurry
Scotoma- grey/black patch over central vision
Light glare, loss of contrast
Photopsia- flashing/flickering lights
Visual hallucinations- Charles Bonnet
Management of Age-related Macular Degeneration
1 week referral
Wet- VEGF- Ranibizumab, Photocoagulation/Photodynamic therapy
Dry- vit A/C/E or zinc
Differentials of dry eye
Hyposecretive- Sjogren’s, lymphoma, sarcoidosis, lacrimal gland obstruction, CNVII damage, anticholinergics, beta blockers, SSRIs, diuretics, antihistamines
Evaporative- Blepharitis, Parkinson’s, thyroid eye disease, vitamin A deficiency, contact lenses
Risk factors for dry eyes
Female, old age, HRT, contact lenses
Investigations for dry eyes
Tear break-up time with fluorescein
Schirmer’s test- filter paper wetting in 5mins < 5mm
Causes of Papilloedema
SOL eg neoplasia, infection, haemorrhage, idiopathic intracranial hypertension, hydrocephalus
Causes of Horner’s syndrome
Central- MS, stroke
Pre-ganglionic- Pancoast tumour
Post-ganglionic- Carotid artery disseciton
What does papilloedema signify?
Raised intracranial pressure
Presentation of Horner’s syndrome
Ptosis, Meiosis (contricted pupil), anhidrosis, pseudo-enopthalmos
Key difference between Horner’s syndrome and 3rd nerve palsy in terms of presentation
Horner’s: constricted pupil
3rd nerve palsy: dilated pupil
Features of hypertensive retinopathy
Arterial narrowing- ‘copper wiring’
Arteriovenous nipping
Vascular leakage
Haemorrhage + exudates
Macular star- thin white streaks around macula
Disc swelling, cotton wool spots, blot (flame) haemorrhages
Management of hypertensive retinopathy
Manage the hypertension
Presentation of Retinitis pigmentosa
Night blindness + tunnel vision
Fundoscopy findings in Retinitis pigmentosa
Black bone spicule-shaped pigmentation in peripheral retina, mottling of retinal pigment epithelium
