Fact-sheet: Transient global amnesia
Updated on 10/04/2019 at 8:53 AM
View all RADEOS cases associated with this fact-sheet
Definition
Sudden-onset anterograde amnesia, completely resolving within less than 24 hours.
More common between 50 and 70 years of age.
The only sequela: lacunar amnesia.
Recurrence is rare.
Triggering event usually identified on patient history:
- Strong negative emotion (grief, funeral) or "positive" emotion (orgasm)
- Sustained effort in cold weather (snow shoveling)
Pathophysiology currently debated: vascular or epileptic origin are the main hypotheses.
Clinical features
Sudden-onset anterograde amnesia, leading the patient to repeatedly ask the same questions, associated with a certain anxiety (=anxious perplexity: very well described by family members).
It fully resolves within less than 24 hours (generally 6 to 8 hours).
The rest of the clinical examination is otherwise strictly normal, notably with no alteration of consciousness or focal neurologic signs.
MRI
Brain MRI, ideally performed between 48 and 72 hours after the episode, may show diffusion hyperintensity, typically punctate, in one or both hippocampi.
If performed too early and negative, the diffusion sequence and the T2 FLAIR sequence can be repeated between 48 and 72 hours.
There is currently no explanation for the delay in appearance of the diffusion finding
Differential diagnosis
Non-spontaneously resolving Korsakoff syndrome
