Isolated Mammillary Body Infarct Causing Global Amnesia: A Case Report

Objectives Mamillary bodies play an important role in human memory and emotions. Vascular lesions causing an isolated mammillary body lesion without affecting the surrounding structures are very rare. Methods A 53-year-old male was brought to the emergency department with acute-onset memory problems suggestive of partial anterograde and retrograde amnesia. Results Magnetic resonance imaging revealed an isolated left mammillary body infarct sparing adjacent structures. Conclusion Mamillary bodies play an intrinsic role in memory formation and retrieval rather than acting as relay-only station for hippocampal projections. Non-hippocampal input from the limbic midbrain via the ventral tegmental nucleus of Gudden could be contributing to its function.