C. Vitreous detachment – Explanation

Flashes and floaters – vitreous/retinal detachment

Flashes and floaters are symptoms of vitreous detachment. The patient is at risk of retinal
detachment and should be referred urgently to an ophthalmologist
Sudden painless loss of vision

The most common causes of a sudden painless loss of vision are as follows:

• ischaemic optic neuropathy (e.g. temporal arteritis or atherosclerosis)
• occlusion of central retinal vein
• occlusion of central retinal artery
• vitreous haemorrhage
• retinal detachment

Ischaemic optic neuropathy

• may be due to arteritis (e.g. temporal arteritis) or atherosclerosis (e.g. hypertensive, diabetic older
  patient)
• due to occlusion of the short posterior ciliary arteries, causing damage to the optic nerve
• altitudinal field defects are seen

Central retinal vein occlusion

• incidence increases with age, more common than arterial occlusion
• causes: glaucoma, polycythaemia, hypertension
• severe retinal haemorrhages are usually seen on fundoscopy

Vitreous haemorrhage

• causes: diabetes, bleeding disorders
• features may include sudden visual loss, dark spots

Retinal detachment

• features of vitreous detachment, which may precede retinal detachment, include flashes of light or
  floaters (see below)

Differentiating posterior vitreous detachment, retinal detachment and vitreous haemorrhage
Posterior vitreous detachment Retinal detachment Vitreous haemorrhage