Ophthalmology Flashcards
Where does the aqueous humor drain?
Via the trabecular meshwork near the anterior chamber at the base of the cornea
What is the role of aqueous humor?
To nourish and protect the eye
What is the choroid?
Made up of connective tissue and blood vessels. Nourishes the outer layers of the retina
What is the ciliary body made up of and what is its role?
- Ciliary muscle which controls the shape of the lens
- Ciliary processes which attach the body to the ciliary muscle
What is the role of the iris?
Alters the diameter of the pupil
What is presbyopia?
Refractive error making it difficult to see up close. Caused by ageing due to loss of elasticity of the crystalline lens
What is the treatment of presbyopia?
Corrective lenses or surgery
What are cataracts?
Opacity of the lens causing blurred or reduced vision
What are the symptoms of cataracts?
- Reduced visual acuity
- glare
- halos around light
- faded colour vision
What are the signs of cataracts?
- defect in red reflex due to light not getting to the retina
Investigations for cataracts
- Ophthalmoscopy
- slit lamp examination
What is the management of cataracts
Lens replacement surgery
What are the complications of cataract surgery?
- posterior capsule opacification
- retinal detachment
- posterior capsule rupture
- endopthalmitis
What is primary open angle closure glaucoma?
Chronic, progressive optic neuropathy resulting in degeneration of the retinal ganglion cells and axons leading to irreversible visual field loss
What are the features of primary open angle glaucoma?
- peripheral field vision loss
- Reduced acuity
- Optic disc cupping
- pallor of optic disc
What are the investigations for primary open angle glaucoma?
- Automated perimetry (to test visual field vision loss)
- slit lamp examination
- applanation tonometry (to measure IOP)
- gonioscopy (to assess fluid in ant chamber)
What is the management of primary open angle glaucoma?
- First line: 360 degrees selective laser trabeculoplasty if IOP ≥24mmHg
- Second line: prostaglandin analogue eye drops to increase uveoscleral flow
What is angle closure glaucoma?
Ophthalmic emergency. Rapid rise in IOP due to the obstruction of the aqueous humor
What are the risk factors of angle closure glaucoma?
- Hypermetropia
- Pupilary dilatation
- lens growth associated with age
What are the symptoms of angle closure glaucoma?
- Severe pain
- Reduced visual acuity
- red eye
- halos around light
- may have systemic upset
What are the signs of angle closure glaucoma?
- Hard, red eye
- Semi dilated, non-reacting pupil
- corneal oedema causing a hazy cornea
What are the investigations for angle closure glaucoma?
- Ocular exam: acuity, pupils
- slit lamp examination
- tonometry
- gonioscopy
- funds examination
What is the management of acute closure glaucoma?
- Prompt ophthalmology referral
- Medical management: topical beta blockers, topical alpha agonists, PGA eyedrops, carbonic anhydrase, systemic hyper osmotic agents (acetazolamide)
- Definitive: laser peripheral iridotomy
What are the types of diabetic eye diseases?
- non proliferative
- proliferative
- Maculopathy
What are the types of NPDR?
- Mild: 1+ microvascularisation
- Moderate: micro aneurysm, blot haemorrhages, hard exudates, cotton wool spots
- Severe: Blot haemorrhages and micro aneurysms in 4 quadrants, venous bleeding in 2 quadrants, IRMA in at least 1
What are the key features of proliferative diabetic retinopathy?
- Retinal neovascularisation
- fibrous tissue formation
- more common in type 1
What are the features of diabetic maculopathy?
- hard exudates
- background changes on macula
What is the management of diabetic maculopathy?
-anti VEGF
What is the management of proliferative diabetic retinopathy?
- Panretinal laser photocoagulation
- can also use VEGF
What are the risk factors for age related macular degeneration
- Age
- smoking
- family history
Wet vs Dry ARMD
- Dry is more common
- Dry is characterised by drusen (yellow round spots)
- Wet is characterised by choroidal neovascularisation
- Wet can cause leakage of serous fluid and blood
- Wet has a worse prognosis
Symptoms of wet ARMD
- subacute onset of visual loss (often bilaterally,centre of the vision)
- worsening night night vision
- glare around lights, photopsia (percerption of flickering or flashing)
- visual hallucinations may also occur resulting in Charles-Bonnet syndrome
Symptoms of dry ARMD
- chronic onset of visual loss (often bilaterally)
- worsening night night vision
- glare around lights, photopsia (percerption of flickering or flashing)
- visual hallucinations may also occur resulting in Charles-Bonnet syndrome
Signs of dry ARMD
- fundoscopy reveals drusen in the macular area, which may form a macular scar
- amsler grid testing may note distortion of line perception
Signs of wet ARMD
- well demarcated red patches (represent intra-retinal or sub-retinal fluid leakage or haemorrhage)
- amsler grid testing may note distortion of line perception
Investigation for ARMD
- slit lamp exam
- colour fundus photography
- fluorescein angiography is utilised if neovascular ARMD is suspected
- ocular coherence tomography (to visualise eye in 3D to see areas that may otherwise be missed)
Management of dry ARMD
zinc with anti-oxidant vitamins A,C and E
Management of wet ARMD
anti vascular endothelial growth factor (VEGF)
Symptoms of central retinal vein occlusion
- sudden painless reduction or loss of visual acuity, usually unilateral
What are the signs on fundoscopy of central retinal vein occlusion?
- Optic nerve head oedema
- Macular oedema
- Flame-shaped haemorrhages
- Cotton wool spots
- Venous tortuosity
What is the management of central retinal vein occlusion?
- anti VEGF
- if neovascularisation is seen then urgent pan-retinal photocoagulation (ischaemic CRVO)
What are the symptoms of central retinal artery occlusion?
- unilateral, painless visual loss in seconds
- may have experienced amaurosis fugax caused by retinal ischaemia
Investigations for central retinal artery occlusion
- complete or relative afferent pupillary defect
- fundoscopy demonstrates a cherry red spot on the macula
- For aetiology: CRP and ESR, carotid artery duplex USS/doppler, echo or holter monitoring
What are the risk factors for retinal detachment?
- age
- previous cataract surgery
- myopia
- eye trauma i.e. boxing
- family history
- previous history of retinal break/detachment
What are the symptoms of retinal detachment?
- floaters or flashes
- sudden, painless, and progressive visual loss described like a curtain coming from the periphery to the central field of vision
Investigations retinal detachment
- fundoscopy: red reflex is lost and retinal folds may appear as pale, opaque or wrinkled forms
- may be a RAPD if optic nerve involved
What is strabismus?
Squint
What are the two types of strabismus
- concomitant (more common)
- paralytic
Concomitant strabismus
Due to an imbalance in the extra ocular muscles
paralytic strabismus
Due to paralysis of the extraocular muscles
Investigations strabismus
- corneal light reflection test
- cover test
Management of strabismus
- referral
- patches to prevent amblyopia (the brain fails to fully process inputs from one eye and over time favours the other eye)
Entropion
In turning of the eyelid
Extropion
out turning of the eyelid
blepharitis
Inflammation of the eyelid margins typically leading to a red eye
Stye
Infection of the eyelid glands
chalazion
Retention cyst of the Meibomian gland. It presents as a firm painless lump in the eyelid
What is the management of blepharitis?
Warm compress, remove debris from the eye
What is the management of a stye?
Hot compress and analgesia
What are the features of bacterial conjunctivitis?
- purulent discharge
- eyes might be stuck together in the morning
What are the features of viral conjunctivitis?
- Serous discharge
- Recent URTI
- Preauricular lymph nodes
What is the management of bacterial conjunctivitis?
- antibiotic eye drops e.g. Chloramphenicol
- don’t wear contact lenses until fully resolved
- fusdic acid in pregnant women
Symptoms of scleritis
- severe pain
- red eye
- swelling
- watering eye
- photophobia
- may have reduced vision
What are the risk factors for scleritis?
- rheumatoid arthritis: the most commonly associated condition
- systemic lupus erythematosus
- sarcoidosis
- granulomatosis with polyangiitis
What is the management of scleritis?
- same day assessment by ophthalmology
- oral NSAIDs
Symptoms of episcleritis
- non painful red eye
- watering eye
- photophobia
Signs of episcleritis
- injective vessels are mobile when pressure is applied
- if the eye redness improves after phenylephrine a diagnosis of episcleritis can be made rather than scleritis
What is the management of episcleritis?
- conservative
- artificial tears can be used
Signs of conjunctival haemorrhage
- red eye: flat, red patch on the conjunctiva
- vision and fundoscopy normal
What is the management of subconjunctival haemorrhage
- conservative, should heal within 2-3 weeks
- can consider artificial tears
Symptoms of corneal abrasion
- red eye, conjunctival injection
- reduced acuity
- feeling of a foreign body
- pain
- photophobia
Signs of corneal abrasion
Fluorescein demonstrates yellow stained abrasion
Management of corneal abrasion
topical antibiotic
Symptoms of corneal foreign body
- eye pain
- foreign body sensation
- photophobia
- watering eye
- red eye
When to refer to ophthalmology for corneal foreign body
- suspected penetrating injury due to high velocity object
- significant orbital or periorbital trauma
- chemical injury
- organic material
- material near the centre of cornea
- any red flags: severe pain; irregular, dilated or non-reactive pupils; significant reduction in visual acuity
symptoms of keratitis
- red eye: pain and erythema
- photophobia
- foreign body, gritty sensation
- hypopyon may be seen
What is keratitis?
inflammation of the cornea
Bacterial causes of keratitis
- Staph aureus
- pseudomonas aeruginosa in contact lens wearers
cause of keratitis with pain out of proportion
acanthamoebic keratitis
Management of keratitis
- same day referral in contact lens wearers
- stop wearing contact lenses
- topical antibiotics - quinolones
- cycloplegic for pain relief
Complications of keratitis
- corneal scaring
- perforation
- endopthalmitis
- visual loss
Symptoms of anterior uveitis
- acute onset, red, painful eye
- pupil may be small +/- irregular due to sphincter muscle contraction
- photophobia (often intense)
- blurred vision
- lacrimation
Signs of anterior uveitis
- ciliary flush: a ring of red spreading out
- hypopyon; pus and inflammatory cells in the anterior chamber
- visual acuity initially normal → impaired
Associated conditions of anterior uveitis
HLA-B27
- ankylosing spondylitis
- reactive arthritis
- ulcerative colitis, Crohn’s disease
- Behcet’s disease
- sarcoidosis: bilateral disease may be seen
Management of anterior uveitis
- urgent ophthalmology review
- cycloplegics to dilate pupil e.g. atropine
- steroid eye drops
Hyphema
Blood in the anterior chamber of the eye
In ocular trauma what is the greatest risk?
Raised intra ocular pressure
Features of orbital compartment syndrome
- eye pain/swelling
- rock hard eyelid
- proptosis RAPD
What is the management of orbital compartment syndrome?
urgent lateral canthotomy (before diagnostic imaging) to decompress the orbit
What is the difference between preseptal/periorbital cellulitis and orbital cellulitis?
- Preseptal: less serious superficial infection anterior to the orbital septum, resulting from a superficial tissue injury
- orbital: result of an infection affecting the fat and muscles posterior to the orbital septum, often from URTI
symptoms of orbital cellulitis
- redness and swelling
- severe pain
- visual disturbance
- proptosis
- ophthalmoplegia
- eyelid oedema and ptosis
- drowsiness/nausea/vomiting
Investigations orbital cellulitis
- FBC
- CT with contrast
- blood cultures and swab
What is the management of orbital cellulitis?
Admission for IV antibiotics
What do cotton wool spots represent?
Retinal infarction
What is retinitis pigmentosa?
Inherited retinal disorder
Symptoms of retinitis pigmentosa
tunnel vision and worsening night vision
Retinitis pigmentosa on fundoscopy
Black pigmentation in the peripheral retina
