NEUROLOGY

Transient global amnesia

  • is a sudden, temporary interruption of short-term memory. Although patients may be disoriented, not know where they are or be confused about time, they are otherwise alert, attentive and have normal thinking abilities.
  • The diagnosis is largely a diagnosis of exclusion.
  • global amnesia
    • Sudden
    • Temporary
    • loss of short-term memory
    • not being able to form new memories
    • Remember their own identity, do not lose self-awareness
    • No focal neurolgoical symptoms
  • Symptoms include:
    • Anxiety and agitation
    • Repeatedly asking questions about what is happening
    • Retaining personal identity during the episode
    • Able to complete complex routine tasks during the episode
    • Absence of signs suggesting damage to the brain tissue
    • Episodes end in 1-8 hours, no more than 24
  • Causes and Risk Factors
    • The cause of transient global amnesia is unknown.
    • People older than 50 are more likely to experience TGA. 
    • Research suggests there also may be a link between patients who have a history of migraines and those who experience TGA.
    • In most cases, there is no activity that triggers a transient global amnesia episode. 
    • In rare cases, certain events can trigger an episode, including:
      • Hard physical activity
      • Sexual intercourse
      • Sudden exposure to very hot or very cold water
      • Emotional stress
      • Mild head trauma
  • Differential Diagnosis
    • Basilar artery thrombosis
    • Cardioembolic stroke/ischemic stroke/transient ischemic attack
    • Complex partial seizures
    • Lacunar syndrome
    • Migraine variants
    • Posterior cerebral artery strok
    • Syncope
    • Temporal lobe epilepsy
    • intoxication on substance
    • Wernicke encephalopathy
    • toxic encephalopathy
    • hypoxia
    • head injury
  • If significant vascular risk factors – consider TIA – but very unlikely presentation
  • Observe in hospital until amnesia resolves
  • If systemically unwell consider encephalitis

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.