Transient global amnesia with unexpected clinical and radiological findings: A case series and systematic review

J Neurol Sci. 2022 Oct 15:441:120349. doi: 10.1016/j.jns.2022.120349. Epub 2022 Jul 23.


Background: Transient global amnesia (TGA) represents a benign neurological syndrome of unknown pathophysiology, often accompanied by vanishing hippocampal punctate diffusion-weighted imaging lesions (HPDL). The literature suggests that TGA may present with unusual features. This study analyses atypical clinical and radiological manifestations of patients with TGA and/or HPDL.

Methods: We retrospectively reviewed patients with atypical clinical or radiological presentations of TGA and/or HPDL in three neurology centers. We also performed a systematic review of literature using predefined search terms. Results were classified as: A) Atypical clinical manifestations of TGA (such as amnesia with additional manifestations, or only non-amnesic manifestations); B) Atypical radiological manifestations of clinically typical TGA.

Results: We identified 83 patients: 18 in our centres (median age 63.5 years, 39% female) and 65 in the literature. In group A, 43 patients presented atypical clinical manifestations such as TGA with added transitory cognitive or sensory-motor deficits, seizures, headaches, but also non-amnesic presentations associated with HPDL and incidental HPDL without symptoms. In group B, 40 patients with typical clinical TGA showed extra-hippocampal punctate diffusion lesions (E-HPDL) which disappeared on follow-up imaging. Using clinical and radiological manifestations, we classified these patients into different categories describing a "TGA-PDL spectrum".

Conclusions: TGA may have atypical clinical manifestations despite typical neuroimaging and patients with typical TGA may show vanishing extra-hippocampal punctate diffusion lesions. TGA, related clinical manifestations, and vanishing punctate diffusion lesions should be considered part of a larger "TGA-PDL spectrum", allowing for better diagnosis of typical and atypical cases and stimulating further studies.

Keywords: Amnesia; Atypical transient global amnesia; Hippocampal punctate diffusion lesion; Magnetic resonance imaging; Transient global amnesia.

Publication types

  • Systematic Review

MeSH terms

  • Amnesia / pathology
  • Amnesia, Transient Global* / diagnostic imaging
  • Amnesia, Transient Global* / etiology
  • Diffusion Magnetic Resonance Imaging / methods
  • Female
  • Hippocampus / pathology
  • Humans
  • Male
  • Middle Aged
  • Retrospective Studies
  • Seizures / pathology