Hippocampal microbleed on a post-mortem t(2)∗-weighted gradient-echo 7.0-tesla magnetic resonance imaging?

The present post-mortem study of a brain from an Alzheimer patient showed on a T(2)∗-weighted gradient-echo 7.0-T MRI of a coronal brain section a hyposignal in the hippocampus, suggesting a microbleed. On the corresponding histological examination, only iron deposits around the granular cellular layer and in blood vessel walls of the hippocampus were observed without evidence of a bleeding. This case report illustrates that the detection of microbleeds on MRI has to be interpreted with caution.