Ophthalmology Flashcards
Acute Glaucoma
Acute angle-closure glaucoma
optic neuropathy
Raised intraocular pressure (IOP) due to
- hypermetropia (long-sightedness)
- pupillary dilatation
- lens growth associated with age
Features
- severe pain: may be ocular or headache
- decreased visual acuity
- symptoms worse with mydriasis (e.g. watching TV in a dark room)
- hard, red-eye
- haloes around lights
- semi-dilated non-reacting pupil
- corneal oedema results in dull or hazy cornea
- systemic upset may be seen, such as nausea and vomiting and even abdominal pain
Ix
- tonometry to assess for elevated IOP
- gonioscopy
Management
- emergency and should prompt urgent referral to an ophthalmologist
- pilocarpine drops
- beta-blocker
- alpha-2 agonist
- intravenous acetazolamide
Definitive management
- laser peripheral iridotomy
Blepharitis
meibomian gland dysfunction or seborrhoeic dermatitis/staphylococcal ix
- Blepharitis is inflammation of the eyelid margins.
Features
- symptoms are usually bilateral
- grittiness and discomfort, particularly around the eyelid margins
- eyes may be sticky in the morning
- eyelid margins may be red. Swollen eyelids may be seen in staphylococcal blepharitis
- styes and chalazions are more common in patients with blepharitis
- secondary conjunctivitis may occur
Management
- softening of the lid margin using hot compresses twice a day
- good eye hygeine
Conjunctivitis
Bacterial conjunctivitis
- Purulent discharge
- Eyes may be ‘stuck together’ in the morning)
Viral conjunctivitis
- Serous discharge
- Recent URTI
- Preauricular lymph nodes
MANAGEMENT
- Chloramphenicol drops are given 2-3 hourly initially whereas chloramphenicol ointment is given qds initially
- topical fusidic acid is an alternative and should be used for pregnant women
- avoid contact lenses
Uveitis
red eye. It is also referred to as iritis.
Features
- acute onset
- ocular discomfort & pain (may increase with use)
- pupil may be small +/- irregular due to sphincter muscle contraction
- photophobia (often intense)
- blurred vision
- red eye
- lacrimation
- ciliary flush: a ring of red spreading outwards
- hypopyon; describes pus and inflammatory cells in the anterior chamber, often resulting in a visible fluid level
- visual acuity initially normal → impaired
Associated conditions
- ankylosing spondylitis
- reactive arthritis
- ulcerative colitis, Crohn’s disease
- Behcet’s disease
- sarcoidosis: bilateral disease may be seen
Management
- urgent review by ophthalmology
- cycloplegics (dilates the pupil which helps to relieve pain and photophobia) e.g. Atropine, cyclopentolate
- steroid eye drops
Cataracts
lens of the eye gradually opacifies i.e. becomes cloudy. difficult for light to reach back of eye
- blurred vision
- Smoking
- Increased alcohol consumption
- Trauma
- Diabetes mellitus
- hypocalcemia
Ix
- A Defect in the red reflex
Management = Surgical or leave it alone
Complications following surgery
- Posterior capsule opacification: thickening of the lens capsule
- Retinal detachment
- Posterior capsule rupture
- Endophthalmitis: inflammation of aqueous and/or vitreous humour
Central Retinal Arterial Occlusion
Central Retinal Vein Occlusion
Central Retinal Artery Occlusion (CRAO):
Features:
Sudden, painless unilateral visual loss
Relative afferent pupillary defect
‘Cherry red’ spot on pale retina
Management:
Difficult; poor prognosis
Identify and treat underlying conditions (e.g., intravenous steroids for temporal arteritis)
Intraarterial thrombolysis may be attempted in acute cases, but mixed trial results.
Central Retinal Vein Occlusion (CRVO):
Risk Factors:
Increasing age
Hypertension
Cardiovascular disease
Glaucoma
PolycythemiFeatures:
Sudden, painless reduction or loss of visual acuity, usually unilateral
Fundoscopy reveals widespread hyperemia, severe retinal hemorrhages (‘stormy sunset’)
Management:
Majority managed conservatively
Indications for treatment:
Macular edema: Intravitreal anti-VEGF agents
Retinal neovascularization: Laser photocoagulation
Key Differential:
Branch Retinal Vein Occlusion (BRVO): Limited fundus area affected, occurs at retinal arteriovenous crossings.
Infective Keratitis
Pseudomonas aeruginosa is seen in contact lens wearers
Keratitis describes inflammation of the cornea. Microbial keratitis is not like conjunctivitis - it is potentially sight threatening and should therefore be urgently evaluated and treated.
Features
* red eye: pain and erythema
* photophobia
* foreign body, gritty sensation
* hypopyon may be seen
Management
- topical antibiotics
- typically quinolones are used first-line
Macular Degeneration
Age-related macular degeneration is the most common cause of blindness in the UK.
Patients typically present with a subacute onset of visual loss with:
a reduction in visual acuity, particularly for near field objects
Management
- vascular endothelial growth factor (VEGF)
Optic Neuritis
multiple sclerosis: the commonest associated disease
diabetes
syphilis
Feautures
- unilateral decrease in visual acuity over hours or days
- poor discrimination of colours, ‘red desaturation’
- pain worse on eye movement
- relative afferent pupillary defect
- central scotoma
Ix
- MRI of the brain and orbits with gadolinium contrast is diagnostic in most cases
Management
- High dose steroids
Periorbital and orbital cellulitis
Orbital Cellulitis:
- Definition: Posterior infection behind orbital septum, potentially fatal.
- Risk Factors: Childhood, sinus infection, lack of Hib vaccination.
- Presentation: Severe ocular pain, proptosis, visual disturbance.
- Differentiation: Proptosis, ophthalmoplegia inconsistent with preseptal cellulitis.
- Investigations: Elevated WBC, contrast CT showing orbital inflammation.
- Management: Hospital admission, IV antibiotics.
Preseptal Cellulitis:
- Definition: Anterior infection, less severe, common in children.
- Risk Factors: Children, winter season.
- Presentation: Red, swollen, painful eye.
- Differentiation: Absence of orbital signs.
- Investigations: Raised inflammatory markers, swab for discharge, CT for differentiation.
- Management: Referral to secondary care, oral antibiotics (co-amoxiclav).
Retinal Detachement
Definition: Separation of neurosensory tissue from pigment epithelium, reversible if treated promptly.
Risk Factors:
- Diabetes mellitus
- Retinal tears from vitreous traction
- Myopia
- Age
- Previous cataract surgery
- Eye trauma
Features:
- New onset floaters or flashes
- Sudden, painless visual field loss
- Progression of shadow in visual field
- Macular involvement worsens visual outcomes
- Reduced peripheral and central vision
Diagnosis:
- Swinging light test for relative afferent pupillary defect
- Fundoscopy reveals loss of red reflex, retinal folds
Management:
- Urgent referral to ophthalmologist (<24 hours)
- Assessment with slit lamp and indirect ophthalmoscopy
Scleritis
Scleritis:
Definition: Full-thickness inflammation of the sclera, non-infective cause.
Risk Factors:
- Rheumatoid arthritis
- Systemic lupus erythematosus
- Sarcoidosis
- Granulomatosis with polyangiitis
Features:
- Red, painful eye
- Gradual decrease in vision
- Watering and photophobia
- Mild to severe pain (compared to episcleritis)
Management:
- Same-day assessment by ophthalmologist
- Oral NSAIDs first-line
- Oral glucocorticoids for severe cases
- Immunosuppressive drugs for resistant cases or underlying diseases.
Thyroid Eye Disease
Visual Field Defects
Left Homonymous Hemianopia:
Visual field defect on the left
Lesion of right optic tract
Homonymous Quadrantanopias (PITS):
Superior: Lesion of inferior optic radiations in temporal lobe (Meyer’s loop)
Inferior: Lesion of superior optic radiations in parietal lobe
Mnemonic: PITS (Parietal-Inferior, Temporal-Superior)
Congruous vs. Incongruous Defects:
Congruous: Complete or symmetrical visual field loss
Incongruous: Incomplete or asymmetric visual field loss
Homonymous Hemianopia:
Incongruous: Lesion of optic tract
Congruous: Lesion of optic radiation or occipital cortex
Macula sparing: Lesion of occipital cortex
Bitemporal Hemianopia:
Lesion of optic chiasm
Upper quadrant defect > Lower quadrant defect: Inferior chiasmal compression (pituitary tumor)
Lower quadrant defect > Upper quadrant defect: Superior chiasmal compression (craniopharyngioma)
