title: "Unforgettable" - a pictorial essay on anatomy and pathology of the hippocampus.
abstract: The hippocampus is a small but complex anatomical structure that plays an important role in spatial and episodic memory. The hippocampus can be affected by a wide range of congenital variants and degenerative, inflammatory, vascular, tumoral and toxic-metabolic pathologies. Magnetic resonance imaging is the preferred imaging technique for evaluating the hippocampus. The main indications requiring tailored imaging sequences of the hippocampus are medically refractory epilepsy and dementia. The purpose of this pictorial review is threefold: (1) to review the normal anatomy of the hippocampus on MRI; (2) to discuss the optimal imaging strategy for the evaluation of the hippocampus; and (3) to present a pictorial overview of the most common anatomic variants and pathologic conditions affecting the hippocampus.
  
  
  CONCLUSIONS
  • Knowledge of normal hippocampal anatomy helps recognize anatomic variants and hippocampal pathology. • Refractory epilepsy and dementia are the main indications requiring dedicated hippocampal imaging. • Pathologic conditions centered in and around the hippocampus often have similar imaging features. • Clinical information is often necessary to come to a correct diagnosis or an apt differential.
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Hospital, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany. sven.dekeyzer@gmail.com.|Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium. sven.dekeyzer@gmail.com.|Department of Medical Imaging, Onze-Lieve-Vrouw Hospital (OLV) Aalst, Moorselbaan 164, 9300, Aalst, Belgium. sven.dekeyzer@gmail.com.
authors.forename: Sven
authors.identifier: http://orcid.org/0000-0002-7779-5740
authors.initials: S
authors.lastname: Dekeyzer
authors.affiliation: Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: Isabelle
authors.initials: I
authors.lastname: De Kock
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Hospital, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany.
authors.forename: Omid
authors.initials: O
authors.lastname: Nikoubashman
authors.affiliation: Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Vanden Bossche
authors.affiliation: Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium.|Department of Medical Imaging, Onze-Lieve-Vrouw Hospital (OLV) Aalst, Moorselbaan 164, 9300, Aalst, Belgium.
authors.forename: Ruth
authors.initials: R
authors.lastname: Van Eetvelde
authors.affiliation: Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: Jeroen
authors.initials: J
authors.lastname: De Groote
authors.affiliation: Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: Marjan
authors.initials: M
authors.lastname: Acou
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Hospital, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Wiesmann
authors.affiliation: Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: Karel
authors.initials: K
authors.lastname: Deblaere
authors.affiliation: Department of Radiology, University Hospital (UZ) Ghent, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: Eric
authors.initials: E
authors.lastname: Achten
keywords: Dementia; Epilepsy; Herpes simplex encephalitis; Hippocampus; MRI