Opthamology Flashcards
What is glaucoma?
Glaucoma is optic nerve damage due to rise in intraocular pressure due to block of aqueous
What is the normal intra-ocular pressure?
Normal IOP is 10-21mmHg
What happens in acute angle-closure glaucoma?
Iris bulges forward and seals off trabecular meshwork
What happens in chronic open-angle glaucoma?
There is increased resistance of trabecular meshwork
What is the Px of acute angle closure glaucoma?
Acute painful red eye
- Blurred vision
- Headaches, N&V
- Seeing halos around lights
o Hazy oedematous cornea - Evening symptoms
What is the Px and Ix of chronic open-angle glaucoma?
Is often asymptomatic
Ix:
- Visual field defects
Peripheral vision closes until tunnel vision
- Fundoscopy -> Cupped optic disc
Optic cup > 0.5 x optic disc - Measure IOP (> 24mmHg)
o Non-contact tonometry = puff of air at cornea
o Goldmann applanation tonometry
Mx of acute angle-closure glaucoma?
->Refer to ophthalmologist
Emergency mx:
- Patient lie flat with head not supported to relieve pressure
- Pilocarpine eye drops
o 2% in blue eyes
o 4% in brown eyes
- Acetazolamide 500mg orally
- Analgesia + anti-emetic
Mx of chronic open-angle glaucoma?
If >24 mmHg:
- Laser trabeculoplasty (SLT)
- Not suitable for SLT ->
1. Prostaglandin analogue
2. B-blocker
3. Carbonic anhydrase inhibitor - Advanced COAG -> glaucoma surgery + mitomycin-C (MMC)
What is blepharitis?
Inflamed eyelids
What are the different types of blepharitis?
Anterior - staphylococcal or seborrheic
Posterior - meibomian
Can also be mixed
Mx of blepharitis?
Mx – no cure, chronic intermittent condition:
1. Self-care (eyelid hygiene and warm press), no eye make-up
- Eyelid measures are ineffective:
o Anterior blepharitis -> Topical antibiotic – Chloramphenicol
o Posterior blepharitis + meibomian gland dysfunction & rosacea -> oral antibiotics - Refer to ophthalmology if severe
What is a chalazion?
Meibomian gland blockage -> non-tender eyelid swelling
What is an entropion and mx?
Eyelids turn inwards with the lashes against the eyeball
-> corneal damage + ulceration
Mx:
Tape eyelid down + lubricating drops
What is an ectropion?
Eyelid turns outwards with inner aspect of eyelid exposed
-> exposure keratopathy
Mx:
Lubricating drops
What is trichiasis and mx?
Inward growth of eyelashes -> corneal damage + ulceration
Mx - Epilation, laser mx
Who gets cataracts?
Rx – elderly, smoking, alcohol, diabetes, steroids, hypocalcaemia
- Can also occur in children (congenital)
Px of cataracts?
- Reduced acuity, progressive blurring, change of colour vision
- Loss of red reflex
- ‘Halos’ around lights
- Gradual visual loss
Px of central retinal artery and vein occlusion?
Both - Sudden, painless unilateral loss of vision, RAPD
Amaurosis fugax – branch retinal artery occlusion
o “Black curtains coming down” – lasts a few minutes
What would be seen on fundoscopy of central retinal artery occlusion and central retinal vein occlusion?
Artery occlusion (light) - pale retina (due to lack of blood flow & oedema) with a cherry-red spot
Vein occlusion (dark) - Flame and blot haemorrhages, optic disc oedema, macular oedema
Mx of central retinal artery occlusion?
Refer to ophthalmology - immediate mx:
o Ocular massage
o Increase blood oxygen content and dilate renal arteries -> Sublingual isosorbide dinitrate and inhaled carbogen
o Reduce ocular pressure ->IV acetazolamide and mannitol
Mx of central retinal vein occlusion?
Mx – treat macular oedema + prevent neovascularisation
- Laser photocoagulation
- Intravitreal steroids
- Anti-VEGF
Difference in px between peri-orbital and orbital cellulitis?
Painful eye movements, blurred vision and altered colour vision in orbital cellulitis
Peri-orbital cellulitis - Eyelid and skin infection in front of the orbital septum
Orbital cellulitis - Infection around the eyeball that involves tissues behind the orbital septum
Chlamydia and gonorrhoea conjunctivitis px:
Chlamydia conjunctivitis:
- Chronic low-grade irritation and mucous discharge, often unilateral
- Follicles “grains of rice” on lower eyelid
Gonorrhoea conjunctivitis:
- Rapid with copious discharge, eyelid swelling & tender lymphadenopathy
Rx of different conjunctivitis?
Bacterial -> Keratitis
Viral -> Keratoconjunctivitis
Gonorrhoea -> Corneal ulceration
Mx of bacterial conjunctivitis?
Self-limiting
If severe -> chloramphenicol drops or fusidic acid
Mx of contact lens conjunctivitis?
Contact lens conjunctivitis -> stop contacts + antibiotics against gm -ve (gentamicin or levofloxacin)
Px of allergic conjunctivitis?
Bilateral ocular itching +/- watery discharge, conjunctival redness & swelling
- Hx of rhinitis, asthma urticaria, eczema
Mx of allergic conjunctivitis?
Mx:
1. Avoidance of allergens, eye care
2. Topical antihistamine or mast cell stabiliser / topical antihistamine
3. Adjuvant – Topical ocular diclofenac
What is uveitis?
Inflammation of the uveal tract (iris, ciliary body and choroid)
Uveitis px:
Red painful eye, blurred vision, eye watering, photophobia
- Deep aching pain
- 20-50 years
- Can be acute or chronic
- Hypopyon – exudate in front of iris
Types of uveitis?
Anterior uveitis – anterior segment of eye (iris & ciliary body) inflammation (90% of cases)
Intermediate uveitis – vitreous inflammation
Posterior uveitis – retina and choroid inflammation
Panuveitis – inflammation in the anterior chamber, vitreous and retina or choroid
Causes of uveitis?
Autoimmune (HLA-B27) [ankylosing spondylitis]
Infective – herpes simplex, hzv, cytomegalovirus, toxoplasmosis
Traumatic, neoplasia (rare)
Non-infectious uveitis mx:
Corticosteroids to reduce inflammation
Mydriatic to paralyse ciliary body (cyclopentolate or atropine)
Difference in px between episcleritis and scleritis?
Episcleritis - normal vision, 50% are bilateral
Scleritis - reduced visual acuity + severe pain
Mx of episcleritis?
Lubricant + NSAIDs
Mx of scleritis?
Emergency as life threatening
Oral NSAIDs + steroids
Ix for keratitis?
Fluorescein
Viral -> dendritic corneal ulcer
Bacterial - > corneal ulcer + hypopyon
Mx for keratitis?
Viral -> refer to ophthalmology, acyclovir
Bacterial -> topical antibiotics (oxaflocin)
Px of keratitis?
Inflammation of the cornea
Px - Painful red eye, photophobia, vesicles around eye, foreign body sensation, watery eye, acute visual loss
Px of optic neuritis?
- Partial or total unilateral visual loss over a few days
- Pain behind eye, worse on movement
- Poor colour discrimination
- Pale and swollen optic disc on fundoscopy
- RAPD, central scotoma
Mx of optic neuritis?
High dose oral steroids (IV methylprednisolone)
Px of age-related macular degeneration?
- Gradual worsening central visual field loss (scotoma)
- Reduced visual acuity
- Distortion of vision where straight lines appear wavy (metamorphopsia)
Fundoscopy of age-related macular degeneration?
Drusen - Yellow deposits under the retina made of lipids
Types of age-related macular degeneration?
- Dry (90% – gradual) – drusen + macular atrophy
- Wet (10% – subacute) – new vessels growing -> leakage of fluid and blood -> oedema
Mx of wet age-related macular degeneration?
Intra-vitreal anti-VEGF (ranibizumab)
Fundoscopy of diabetic retinopathy?
- Microaneurysms -> Blot haemorrhages
- Exudate (cotton wool spots)
- New blood vessel growth
- Oedema
How is diabetic retinopathy classed?
Is it proliferative? (is there new vessel growth?)
Is there maculopathy? (is the macula thickened?)
Complications of diabetic retinopathy?
- Retinal detachment
- Vitreous haemorrhage
- Optic neuropathy
- Glaucoma
- Cataracts
Px of retinal detachment?
Sudden onset, painless progressive visual field loss, floaters, recurrent flashes, and progressive visual loss
Mx of diabetic retinopathy?
Laser photocoagulation
Anti-VEGF (ranibizumab)
Vitreoretinal surgery
Keith Wagner classification of hypertensive retinopathy?
Stage:
I Arteriolar narrowing
II Arteriovenous nipping
III Retinal haemorrhages, exudates, cotton wool spots
IV Papilloedema
Visual field loss types:
Optic nerve defect – Monocular vision loss
Optic chiasm defect – bitemporal hemianopia
Optic tract defect or occipital cortex (macula spared) – Homonymous hemianopia
