Late-onset migraine-like aura attacks without headache or with mild headache, also termed “amyloid spells”, caused by and associated with the other clinical features of cerebral amyloid angiopathy, often in the setting of convexal subarachnoid haemorrhage.
- New attacks of migraine-like aura, with or without mild headache, fulfilling criterion C
- Neuroimaging or brain biopsy evidence of cerebral amyloid angiopathy (CAA)
- Evidence of causation demonstrated by one or more of the following:
- aura has developed in close temporal relation to other symptoms and/or clinical signs of CAA, or led to its discovery
- aura has significantly worsened in parallel with clinical and/or radiological signs of worsening of the CAA
- onset after 50 years of age
- Not better accounted for by another ICHD-3 diagnosis1.
Blood-sensitive MRI sequences are important in diagnosing cerebral amyloid angiopathy, and should be performed in any patient with late-onset migraine-like aura.
Cerebral amyloid angiopathy (CAA) is a small-vessel disorder associated with progressive amyloid deposition in the walls of cortical and leptomeningeal vessels. Sporadic forms are more common than inherited familial forms.
CAA is a major cause of lobar symptomatic intracerebral haemorrhage, transient focal neurologic episodes in the elderly, and cognitive impairment. Transient focal neurological episodes include both positive migraine aura-like (spreading paraesthesias and/or positive visual phenomena) and negative TIA-like neurological symptoms, and may be caused by superficial cortical siderosis or convexal subarachnoid haemorrhage. These episodes are associated with a high early risk of symptomatic intracerebral haemorrhage.