Ophthalmology Flashcards
Risk factors for age-related macular degeneration
Advancing age
Female > male
Smoking
FHx
Hypertension, dyslipidaemia + DM - cardiovascular disease
White or Chinese ethnic origin
Characteristic features of dry macular degeneration
Atrophics
Drusen - yellow round spots in Bruch’s membrane
Characteristic features of wet macular degeneration
Choroidal neovascularisation
Features of both wet + dry macular degeneration
Atrophy of retinal pigment epithelium
Degeneration of photoreceptors
Can have drusen in bot
Symptoms of ARMD
Gradual worsening central visual field loss
Reduced visual acuity
Crooked or wavy appearance to straight lines
More acute in wet
Signs of ARMD
Amsler grid test - distortion of straight ligns
Snellen chart - reduced acuity
Scotoma - central patch of vision loss
Fundoscopy –> Drusen
Managament of dry AMD
Lifestyle measures to slow progression:
- Avoid smoking
- Control blood pressure
- Vitamin supplementation
Management of wet AMD
Anti-VEGF (vascular endothelial growth factor) medications e.g.
- Ranibizumab
- Bevacizumab
- Pegaptanib
injected into vitreous chamber once a month
Risk factors for vitreous haemorrhage
Diabetes - proliferative diabetic retinopathy is most common cause
Trauma
Anticoagulants
Coagulation disorders
Severe short sightedness
Symptoms of vitreous haemorrhage
Painless visual loss or haze
Red hue in vision
Floaters or shadows/dark spots in vision
Signs of vitreous haemorrhage
Decreased visual acuity
Visual field defect if severe haemorrhage
Pathophysiology of acute angle-closure glaucoma
Rise in intraocular pressure, secondary to impairment of aqeuous outflow
Factors predisposing to acute angle-closure glaucoma//risk factors
Hypermetropia (long-sightedness)
Pupillary dilatation
Lens growth associated with age
Increasing age
Female
FHx
Chinese + East Asian ethnic origin
Shallow anterior chamber
Glaucoma
Optic nerve damage caused by significant rise in intraocular pressure
Medications that may precipitate acute angle-closure glaucoma
Adrenergic medications e.g. noradrenlaine
Anticholingeric medications e.. oxybutynin + solifenacin
Tricyclic antidepressants e.g. amitryptiline, due to anti-cholinergic effects
Symptoms of AACG
Severely painful red eye
Blurred vision
Halos around lights
Headache, N+V
Signs of AACG
Red-eye
teary
Hazy cornea
Decreased visual acuity
Dilatation of pupil
Fixed pupil size
Firm eyeball on palpation
Initial management of AACG
Lie on back without pillow
Pilocarpine eye drops - to constrict pupil
Acetazolamide 500mg oral
Analgesia + antiemetic
Medical options for secondary care management of AACG
Pilocarpine
Acetazolamide - oral or IV
Hyperosmotic agents e.g. glycerol or mannitol
Timolol = beta-blocker
Dorzolamide
Brimonidine
Definitive treatment for AACG
Laser iridotomy
Blepharitis
Inflammation of eyelid margins
Causes/associations with blepharitis
Meibomian gland dysfunction
Seborrhoeic dermatitis/staphylococcal infection
More common in rosacea
Feature of blepharitis
Usually bilateral
Grittiness + discomfort - especially around eyelid margins
Eyes may be sticky in morning
Eyelid margins may be red
Can lead to styes + chalazions
Management of blepharitis
Hot compresses twice daily
Gentle cleaning of eyelid margins - use cotton wool dipped in sterilised water + baby shampoo
Consider lubricating eye drops e.g. hypromellose, polyvinyl alcohol + carbomer
Risk factors for retinal detachment
Posterior vitreous detachment
Diabetic retinopathy
Trauma to the eye
Retinal malignancy
Older age
Family History
Presentation of retinal detachment
Flashes + floaters = key
Painless
Peripheral vision loss - sudden + like a shadow
Blurred or distorted vision
Management of retinal detachment
Immediate ophthalmology referral
Reattach retina –>
- Vitrectomy
- Scleral buckling
- Pneumatic retinopexy
Where is aqueous humour found
In the anterior chamber - between cornea + iris
In the posterior chamber - between lens + iris
Normal intraocular pressure
10-21mmHg
Open-angle glaucoma pathophysiology
Gradual increase in resistance through the trabecular meshwork –> aqueous humour cannot exit the eye easily –> gradual increase in pressure
What causes cupping of the optic disc
Increased pressure in the eye –> pressure on indent, making it wider + deeper
What is cupping of the optic disc
When optic cup (central indent in optic disc) > half size of optic disc
Presentation of open-angle glaucoma
Often asymptomatic
Affects peripheral vision first –> tunnel vision
Gradual onset of fluctuating pain, headaches, blurred vision + halos around lights (esp. at night)
Risk factors for open angle glaucoma
Increasing age
Family History
Afro-Caribbean ethnicity
Myopia
Hypertension
Diabetes Mellitus
Corticosteroids
Signs of open angle glaucoma on fundoscopy
Optic disc cupping
Optic disc pallor (atrophy)
Bayonetting of vessels
Cup notching, disc haemorrhages
First line management of open angle glaucoma
Started if intraocular pressure >24 mmHg
Prostaglandin analogue eye drops e.g. latanoprost
Risk factors for central retinal artery occlusion
Same as for other cardiovascular disease as most common cause = atherosclerosis
Also caused by giant cell arteritis –> higher risk if white, >50, already affected by GCA or PMR
Presentation of central retinal artery occlusion
Sudden, painless loss of vision
Relative afferent pupillary defect
Fundoscopy findings in central retinal artery occlusion
Pale retina/opacified
Cherry-red spot (macula showing choroid below)
Immediate management of central retinal artery occlusion
Immediate ophthalmology referral
Ocular massage
Remove fluid from anterior chamber
Inhaling carbogen to dilate artery
Sublingual isosorbide dinitrate
Treat + manage underlying condition e.g. GCA with high-dose steroids
Stage I hypertensive retinopathy
Mild narrowing of arterioles
Increased light reflex
Stage II hypertensive retinopathy
Arteriovenous nipping
Stage III hypertensive retinopathy
Cotton-wool exudates
Flame and blot haemorrhages –> may collect around fovea, causing ‘macular star’
Stage IV hypertensive retinopathy
Papilloedema
What is silver wiring
aka copper wiring
Walls of arterioles become thickened + sclerosed –> increased reflection of light
What is arteriovenous nipping
Arterioles cause compressions of veins when they cross, due to sclerosis + hardening of the arterioles
Features of mild non-proliferative diabetic retinopathy
Microaneurysms
Features of moderate non-proliferative diabetic retinopathy
Microaneurysms
Dot + blot haemorrhages
Hard exudates
Cotton wool spots
Venous beading
Features of severe non-proliferative diabetic retinopathy
Blot haemorrhages + microaneurysms in 4 quadrants
Venous beading in 2 quadrates
Intraretinal microvascular abnormality in any quadrant
Features of proliferative diabetic retinopathy
Neovascularisation
Vitreous haemorrhage
Diabetic maculopathy
Macular oedema
Ischaemic maculopathy
Complications of diabetic retinopathy
Retinal detachment
Vitreous haemorrhage
Rebeosis iridis - new vessel formation in iris
Optic neuropathy
Cataracts
Management of diabetic retinopathy
Laser photocoagulation
Anti-VEGF medications
Vitreoretinal surgery
Scleritis
Inflammation of full thickness of the sclera
