Transient Global Amnesia

Dr. Greg McCormick

Case Report: 

61 y.o. woman with a PMH of HTN brought in by EMS presenting after MVA. Per EMS, patient’s car hit the guard rail, minimal car damage. No airbag deployment, broken windows. Patient self-extricated without any issues. Does not recall any events immediately prior to or after the MVA. Patient remembers leaving work and getting her car, but does not recall how she arrived to the hospital.  

Patient alert & oriented x 3, appears confused. Physical exam unremarkable: no injuries, normal neurologic exam. Works as a pharmacist and is unable to recall which medications she takes. Repetitively asking how she arrived to the hospital. Denies EtOH / drug use.  

CT head, MRI unremarkable; no evidence of ischemic changes. Patient admitted overnight and confusion resolved by the next morning. Patient still does not recall what transpired after she left work yesterday afternoon, but has no long-term memory deficits.  

Transient Global Amnesia 

TGA is a “clinical syndrome characterized by the acute onset of anterograde amnesia” and confusion which cannot be attributed to an alternative neurologic diagnosis (i.e. stroke, TIA, epilepsy).TGA usually self resolves within 24 hours. Patients are unable to recall recent events while experiencing the TGA episode, and usually repeat questions during the episode. Some patients may go on to experience recurrent episodes. Patient who experience TGA recover memory function, but usually do not remember what happened throughout the amnesic episode.  

No single etiology for this condition has been identified, but epidemiologic and imaging data suggests associations with vascular disease, history of migraines, and epilepsy.  

References:  

Transient global amnesia. Genetic and Rare Diseases Information Center. National Institute of Health. 10/31/2016. Accessed 1/12/22. https://rarediseases.info.nih.gov/diseases/8172/transient-global-amnesia 

Arena JE, Rabinstein AA. Transient global amnesia. Mayo Clin Proc. 2015 Feb;90(2):264-72. doi: 10.1016/j.mayocp.2014.12.001. PMID: 25659242.