Der Hippokampus

Zusammenfassung

Die paarige Struktur Hippokampus ist für das Gedächtnis und im weiteren Sinne für das „Menschsein“ von elementarer Bedeutung, sie wird heute in vivo mit einer hochaufgelösten, „anatomisch orientierten“ MRT untersucht. Wichtigste Sequenzen sind koronare, 2 oder 3 mm dicke T2w oder FLAIR-TSE-2D-Aufnahmen, die senkrecht zur Längsachse des Hippokampus verlaufen. Alternativ werden zunehmend isotrope 3D-FLAIR- und T2-Aufnahmen mit 1 mm³ Voxelgröße akquiriert. Verschiedene voxelbasierte Postprocessing-Methoden (automatisierte Volumetrie, Relaxometrie, FLAIR-Signalanalyse) sind noch keine klinische Routine. In dieser Übersichtsarbeit werden diagnostische „pitfalls“ und Befunde bei den häufigen Hippokampuserkrankungen dargestellt.

Abstract

The twin structure hippocampus is of vital importance for memory and „human being“, it is in vivo examined by anatomically oriented, high-resolution MRI. Important MR sequences are coronal, 2 or 3 mm thick, T2-weighted or FLAIR fast spin echo sequences which are angulated perpendicular to the length axis of the hippocampus. Alternatively, 3 D FLAIR and T2-weighted sequences with isotropic 1 mm³ voxel are increasingly acquired. Voxel-based postprocessing (volumetry, relaxometry, FLAIR signal analysis) is not clinical routine yet. This review article focuses on diagnostic pitfalls and illustrates MR imaging findings of the most common diseases.

Keywords

Hippocampus - memory - epilepsy - MRI - hippocampal sclerosis - ammon’s horn sclerosis

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