Differentials

Question 1

What are the differentials of an acutely red and painful eye?

Answer 1

• Corneal abrasion or Superficial foreign body
• Acute Glaucoma
• Conjunctivitis
• Optic Neuritis
• Anterior Uveitis
• Scleritis
‣ Episcleritis tends to be less painful and its vessels blanch when pressed with a cotton bud
• Endophthalmitis (typically after eye surgery)

Question 2

What are the differentials of Gradual loss of vision?

Answer 2

• Cataract
• Age-related Macular Degeneration
• Chronic Glaucoma
• Diabetic and Hypertensive retinopathy
• Refractive Error - If young, normal blurred vision and otherwise fit and well!

Question 3

What are the differentials of Sudden loss of vision?

Answer 3

• Acute Glaucoma
• Central Retinal Vein Occlusion
‣ Far more common than retinal artery occlusion (Amaurosis Fugax/Retinal TIA)
• Retinal detachment
• Vitreous haemorrhage
• Giant Cell Arteritis

Question 4

What are the differentials of Diplopia?

Answer 4

• Intoxication – esp. alcohol, opiates, benzos
• 3rd, 4th or 6th nerve palsy
• Myasthenia Gravis
• Strabismus – Squint, which is a common cause in children
• Thyroid eye disease – Exophthalmos compresses extraocular muscles and reduces space for the eye to rotate