Amnesia global transitoria y quiste aracnoideo de la fosa craneal media: una hipótesis

Focal magnetic resonance (MR)-signal diffusion-weighted imaging changes in CA-1 sector of the hippocampus are detected in most patients during episodes of transient global amnesia (TGA), usually limited to one side. We report a 65-year old woman who developed TGA by current diagnostic criteria after being awakened from a napping by a telephone call reporting mournful news. A MR imaging of the brain showed a large arachnoid cyst of the right middle cranial fossa, a finding thought to represent temporal lobe hypogenesis. We suggest that asymmetric development of mesial temporal structures may also represent a risk factor for TGA.