Opthalmology Flashcards
What is Scleritis?
- Inflammation of sclera
- Painful, destructive and vision threatening disorder
- 50% associated with systemic illness (RA, Granulomatosis w/ polyangitis)
- 90% anterior, 10% posterior (in relation to extra ocular muscles)
- Posterior and necrotising anterior are the most serious due to delayed recognition and close to the optic nerve
H&E of Scleritis
- Severe boring pain, constant
- Out of proportion to redness
- Exacerbated on eye movement
- May have photophobia
- Diplopia and reduced vision (compression of optic nerve)
- Posterior scleritis may have less redness
Investigations of Scleritis
- Slit-lamp
- Anterior - scleral oedema + dilation deep episcleral vascular plexus
- Posterior - choroidal thickening and retinal detachment
- B-scan ultrasonography to confirm scleral thickening
- CT/MRI to exclude orbital lesion
Management of Scleritis
Mild-moderate (anterior)
- Mild symptoms - NSAIDs
- No response to NSAIDs or moderate - high dose prednisolone (gradually taper)
Severe (posterior/nercotising anterior)
- High dose prednisolone + rituximab (anti-CD20)
- If no response - cyclophosphamide (brief course due to high toxicity)
- If managed switch to azathioprine/methotrexate/mycophenolate mofetil
Stop all immunosuppressives 6-12 months after remission (12-24 if necrotising anterior)
Stages of Diabetic Eye Disease
Background
Pre-proliferative
Proliferative
Maculopathy
Fundoscopy findings for Background retinopathy
Dot and blot haemorrhages, hard exudates
Fundoscopy findings for Pre-proliferative stage
Dot + blot haemorrhages, hard exudates
AND
Cotton-wool spots
Fundoscopy findings for Proliferative stage
Dot + Blot haemorrhages, hard exudates
AND
Cotton-wool spots
AND
New vessels on optic disc (neovascularisation)
Often associated with retinal detachment and vitreous haemorrhage -> visual loss
Fundoscopy findings for Maculopathy
Dot + Blot haemorrhages, hard exudates
AND
Cotton-wool spots
AND
Neovascularisation
AND
Hard exudates near macula
Management of Background retinopathy
Improve glycemic control
Management of Pre-proliferative/ Proliferative retinopathy
Pan-retinal laser photocoagulation
Management of Maculopathy
Intravitreal VEGF (vascular endothelial growth factor) inhibitors
What is Optic Neuritis?
Inflammation and swelling of the optic nerve which subsequently causes damage to it
Causes of Optic Neuritis
- Multiple sclerosis
- Diabetes
- Syphilis
H&E of Optic Neuritis
- 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
Investigations for Optic Neuritis
MRI of brain and orbits with gadolinium contrast
Management of Optic Neuritis
High dose steroids
- IV methylprednisolone
What is Conjunctivitis?
Inflammation of the lining of the eyelids
Most commonly allergic, can be viral, bacterial or herpetic
Causes of Conjunctivitis
Allergic - type 1 immune response
Viral - adenovirus, can be HSV
Bacterial - pneumococcus, Staph. a, Moraxella catarrhalis
H&E of Conjunctivitis
Allergic:
- Watery discharge, itchy, nasal symptoms, bilateral disease
Viral:
- Watery discharge, sticky eyes, recent URTI, bilateral disease +/- herpetic vesicular rash (if HSV)
Bacterial:
- Purulent discharge, sticky eyes, unilateral, pannus (blood vessels invading)
Investigations for Conjunctivitis
- Slit lamp
- Can do gram stains if suspecting N. gonorrhoea
General Advice/ Management of Conjunctivitis
- Don’t share towels/household items
- Don’t itch/touch
- Don’t wear contacts
- Wash hands and face regularly and clean eyes with cotton wool
Management of Infective Conjunctivitis
Topical broad-spectrum Abx
- Chloramphenicol
- Fusidic Acid in pregnant women
- Azithromycin/ Erythromycin
Management of Allergic Conjunctivitis
Antihistamines
If unresolving - topical steroids or topical sodium cromoglycate
What are congruous/ incongruous defects?
Congruous - complete or symmetrical visual field loss
Incongruous - incomplete or asymmetric defect
Defects causing Homonymous Hemianopia
Incongruous: lesion of optic tract
Congruous: lesion of optic radiation or occipital cortex
Macula sparing: lesion of occipital cortex
LEFT HH will be defect to the LEFT of EYE = lesion of RIGHT side
Defects causing Homonymous Quadrantopias
Superior: lesion of the inferior optic radiations in the temporal lobe (Meyer’s loop)
Inferior: lesion of the superior optic radiations in the parietal lobe
Mnemonic: PITS (Parietal-Inferior, Temporal-Superior)
Defects causing Bitemporal Hemianopia
Lesion of optic chiasm
Upper quadrant defect > lower quadrant defect: Inferior chiasmal compression (MC pituitary tumour)
Lower quadrant defect > upper quadrant defect: superior chiasmal compression, MC a craniopharyngioma
