Transient global amnesia

Transient global amnesia (TGA) is a clinical syndrome with no clear etiology identified. Most symptoms are transient and resolve within a few hours. 

Most common in patients of older age (50-70 years old).

Anterograde and partial retrograde amnesia lasting less than 24 hours without any other neurological or congestive symptoms. Most cases show complete resolution of symptoms within a few hours from onset of symptoms.

Several hypotheses (e.g. epileptic phenomena, stroke, focal ischemia) have been proposed with no consensus on the exact mechanism 1.

Brain CT scan and conventional sequences of MRI brain show no abnormalities.

Prospective and retrospective studies based on a small number of TGA patients can detect small punctate regions of abnormally restricted diffusion on DWI/ADC sequences in the CA1 area of the hippocampus (lateral edge of the hippocampal gyrus abutting the temporal horn). These lesions can be bilateral and even multifocal 2-4

No treatment is required and the condition tends to not recur 5.

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Article information

rID: 19071
Synonyms or Alternate Spellings:
  • Transient global amnesia (TGA)

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Cases and figures

  • Case 1
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  • Case 2
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  • Case 3
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  • Case 4
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  • Case 5: bilateral
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