Causes of Transient Neurological or Monocular Visual Symptoms
| Cause | Comment |
|---|---|
| Migraine aura (with or without headache) | Stereotypical positive symptoms such tingling and visual symptoms, spreading over several minutes and typically resolving within 60 min. Often positive family history for migraine. |
| Partial epileptic seizure | Positive symptoms (jerking or tingling, marching over several seconds). May have impaired awareness (partial complex seizure). |
| Transient global amnesia | Loss of anterograde memory usually accompanied by repetitive questioning. Resolves usually within 6 h. No language deficit. Able to recognize surroundings and familiar individuals. |
| Metabolic | Hypoglycaemia: consider if recurrent events associated with low blood glucose. See Chapter 81. |
| Structural lesion | For example brain tumour, chronic subdural haematoma. See Chapter 72. |
| Demyelination | Subacute onset in young adults. MRI clarifies diagnosis. |
| Mononeuropathy | Look for lower motor neuron signs. |
| Myasthenia gravis | Check for fatigability. |
| Monocular visual symptoms | Ocular or optic nerve disease. See Chapter 19. |