Background: This study aimed to have international experts converge on a harmonized definition of whole hippocampus boundaries and segmentation procedures, to define standard operating procedures for magnetic resonance (MR)-based manual hippocampal segmentation.
Methods: The panel received a questionnaire regarding whole hippocampus boundaries and segmentation procedures. Quantitative information was supplied to allow evidence-based answers. A recursive and anonymous Delphi procedure was used to achieve convergence. Significance of agreement among panelists was assessed by exact probability on Fisher's and binomial tests.
Results: Agreement was significant on the inclusion of alveus/fimbria (P = .021), whole hippocampal tail (P = .013), medial border of the body according to visible morphology (P = .0006), and on this combined set of features (P = .001). This definition captures 100% of hippocampal tissue, 100% of Alzheimer's disease-related atrophy, and demonstrated good reliability on preliminary intrarater (0.98) and inter-rater (0.94) estimates.
Discussion: Consensus was achieved among international experts with respect to hippocampal segmentation using MR resulting in a harmonized segmentation protocol.
Keywords: Alzheimer's disease; Anatomical landmarks; Atrophy; Delphi procedure; Enrichment; Harmonization; Hippocampal atrophy; Hippocampus; MCI; Magnetic resonance; Manual segmentation; Medial temporal lobe; Neuroimaging; Reliability; Standard operational procedures; Volumetry.
Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.