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Posterior ischemic optic neuropathy (PION)
Retina & Vitreous
Key Points
- •PION is acute ischaemia of the retrobulbar optic nerve - presents with sudden visual loss and a normal optic disc (no swelling), distinguishing it from AION
- •Three types: arteritic (GCA - emergency), non-arteritic (vascular risk factors), and perioperative (spinal/cardiac surgery - often bilateral)
- •Always rule out GCA in patients >50: ESR, CRP, temporal artery biopsy; start IV methylprednisolone 1g/day immediately if suspected
- •Perioperative PION - prevention is key: avoid prolonged prone positioning, maintain BP, minimise blood loss; no proven treatment once established
- •Visual prognosis is poor in all forms - treatment of arteritic PION aims to protect the fellow eye, not restore vision
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Keep reading Posterior ischemic optic neuropathy (PION)
16 more sections are included with the Clinical plan.
- Definition
- Epidemiology
- Aetiology and causes
- Pathogenesis
- Classification
- Risk factors and associations