Pallid optic disc oedema in non-arteritic anterior ischaemic optic neuropathy without a conventional 'disc at risk'

Non-arteritic anterior ischaemic optic neuropathy (NAION) is typically characterised by non-pallid optic disc oedema and a contralateral small optic nerve head. Typically, the optic cup is absent or small with a cup-to-disc ratio of less than 0.3 termed 'disc at risk'. While systemic and ocular risk factors are identified as risk factors of NAION, the exact pathogenesis of NAION is not fully understood. We report a case of NAION with pallid optic disc oedema and the absence of a disc at risk in a patient with multiple vascular risk factors, suggesting an underlying severe atherosclerotic pathology. This case highlights that NAION may present with atypical features with pallid optic disc oedema and absence of a disc at risk and highlights atherosclerosis as an associated underlying risk factor.