Transient global amnesia: does MRI brain imaging provide helpful diagnostic information? A systematic review. Abstract: Background: Transient Global Amnesia (TGA) is a clinical syndrome characterised by acute onset of anterograde amnesia lasting for up to 24 hours. The role of Magnetic Resonance Imaging (MRI) with Diffusion Weighted Imaging (DWI) in the management of TGA is unclear. Aims: This systematic review aimed to: determine the prevalence and type of structural abnormalities on MRI; determine the effects of time to imaging on the prevalence of any identified abnormalities; and to determine whether there is evidence to support an ischaemic aetiology to TGA. Methods: The published literature was systematically reviewed using predefined criteria to identify studies using MRI in patients with TGA. Results: 116 manuscripts were identified. Incidental abnormalities were identified in 3% to 17.4% of cases. It was not possible to accurately ascertain the prevalence of relevant DWI+ lesions. Optimal DWI lesion detection rates occurred at 24-48 hours from symptom onset. Based on current data there is no evidence to suggest an ischaemic aetiology to TGA. Conclusion: If brain MRI is undertaken following TGA, clinicians should note the risk of identifying incidental abnormalities. The optimal time for DWI lesion detection is between 24 and 48 hours but there is no convincing evidence to support an ischaemic aetiology to TGA. This review provides helpful information for clinicians to inform their decision making. Project type: Systematic review Imaging keywords: Diffusion weighted imaging (DWI) Magnetic resonance imaging (MRI) Application / disease keywords: Anterograde amnesia Transient global amnesia (TGA) Supervisor(s): Dr William Whiteley Programme: Neuroimaging for Research MSc Year: 13-14 This article was published on 2024-08-22
