Anterior portion of the cingulate gyrus: A novel location for transient global amnesia?

Transient global amnesia (TGA) is characterized by abrupt transient loss of anterograde memory, lasting up to 24 hours, and no other focal neurological signs. We report the case of a right-handed 71-year-old female patient who presented temporal-spatial disorientation 5 minutes after ingestion of 1000 ml of iodinated contrast. The patient had mild temporal-spatial disorientation, with significant deficit in anterograde memory. After 12 hours under observation, the patient progressed to gradual improvement and was discharged. A reevaluation after 15 days showed normal cortical functions, score on mini-mental state exam of 30, and unaffected working and recall memory. MRI performed 48 hours after the event showed hypersignal in the diffusion sequence in the anterior portion of the cingulate gyrus, with hypointense signal in MAP/ADC, confirming a finding consistent with TGA. No previous reports in the literature have described the location affected in this patient, rendering it a novel site consistent with this diagnosis.