Reversible temporal hypodensity on CT in a patient with minor head injury: Transient global amnesia or contusion?

Transient global amnesia (TGA) is a condition characterized by a sudden, temporary lapse in memory without focal neurological deficits, usually in middle aged adults, sometimes precipitated by an inciting event. We describe a case of a young patient, who presented with a constellation of symptoms consistent with TGA post-concussion with a right temporal lobe hypodensity on CT head. This patient’s memory returned to baseline within 24 hours, with only a mild residual headache which resolved within the next day and no MRI findings 48 hours after, illustrating that his clinical trajectory favours TGA rather than post-concussive amnesia. While the pathophysiology of TGA is still a mystery, clinicians and researchers continue to hypothesize the anatomical basis of this condition.