Ischaemic optic neuropathy 

In ischaemic optic neuropathy, there is occlusion of the small arteries around the optic disc. 
It is important to differentiate arteritic optic neuropathy from non-arteritic optic neuropathy. 
Arteritic optic neuropathy is caused by giant cell arteritis and prompt treatment with systemic 
steroid can prevent involvement of the contralateral eye. 

Presentation:

  • Sudden visual loss in a patient with a history of persistent headache (which may be 

    • temporal or occipital) or jaw claudication (pain in the jaw on eating) suggest giant cell arteritis
Examination:
  • The visual loss is usually profound 6/60 or less in giant cell arteritis and less severe in 

    • non-arteritic ischaemic optic neuropathy.
  • Afferent pupillary defect is common
  • Fundal examination reveals swollen optic disc caused by occlusion of the arteries around 

    • the optic disc
  • In giant cell arteritis there is tenderness over the affected artery (usually the temporal artery) 

    • and the artery is usually not palpable.
Management:
  • Refer immediately any patient with sudden visual loss and swollen disc for exclusion of 

    • giant cell arteritis.
  • ESR and the C reactive protein are usually raised in giant cell arteritis but non-specific. 

    • A definite diagnosis is by temporal artery biopsy for the typical granulomatous changes 
    in the arterial wall. However, systemic steroid is usually given while this is arranged.
       
Figure 1
Swollen optic disc with decreased vision and headache 
requires the exclusion of  giant cell arteritis. 

Return to sudden visual loss