Harmonized Protocol for Segmentation of the Hippocampal Tail on High‐Resolution In Vivo MRI From the Hippocampal Subfields Group ( HSG )
Year: 2026
Type: article
Abstract: The hippocampus is a heterogeneous structure with cytoarchitectonically distinct subfields that exhibit heterogeneous lifespan trajectories and are differentially susceptible to diseases. Advances in high-resolution imaging have accelerated research on these structures, yet variability in segmentation protocols limits cross-study comparability. The Hippocampal Subfields Group (HSG) is an international consortium addressing this challenge by developing a reliable, accessible, and freely available segmentation protocol for high-resolution T2-weighted 3T MRI scans (http://www.hippocampalsubfields.com). Here, we present the harmonized protocol for the posterior portion of the hippocampus (the "tail"), complementing the previously established "body" protocol, and with an anterior "head" protocol under development. The tail protocol provides standardized definitions of the external boundaries for the posterior-most extent of the hippocampus, facilitating consistent segmentation from surrounding tissues. The research community was extensively involved through an online survey that incorporated comprehensive protocol details, feasibility assessments, tutorial videos, and illustrative segmentations. Through this collaborative process, consensus emerged to exclude subfield labeling in the hippocampal tail due to limited visibility of internal landmarks and substantial anatomical variability in this region. All proposed boundary guidelines were deemed clear and agreed upon via a Delphi procedure. The harmonized tail protocol has high intra- (Averaged ICC(2, 1) > 0.98; Averaged Dice Similarity Coefficient = 0.92) and inter-rater reliability (Averaged ICC(2, k) > 0.98; Averaged Dice Similarity Coefficient = 0.86) and offers a practical framework for replicable segmentation. By establishing standardized guidelines, this protocol enhances comparability of findings across developmental, aging, and clinical research and is compatible with ongoing technological advances.
Source: Hippocampus
DOI: 10.1002/hipo.70143
Authors: Robin de Flores, Kelsey L. Canada, Thackery Brown, Nicole J. Gervais, Anne Maass, Gustaf Rådman, Jonathan Shine, Hannah L. Tucker, Eóin N. Molloy, Jenna N. Adams, Michelle Baca Reinke, Arnold Bakker, David Berron, Marshall A. Dalton, Kristen M. Kennedy, Renaud LaJoie, Susanne G. Mueller, Noa Ofen, Rosanna K. Olsen, Naftali Raz, Tracy Riggins, Karen M. Rodrigue, Craig Stark, Lei Wang, Laura E. M. Wisse, Paul A. Yushkevich, Valerie A. Carr, Ana M. Daugherty, the Alzheimer's Disease Neuroimaging Initiative, the Hippocampal Subfields Group
Institutions: Inserm, Normandie Université, Université de Caen Normandie, University of Massachusetts Amherst, Georgia Institute of Technology, University of Groningen, German Center for Neurodegenerative Diseases, Lund University, University of California, Irvine, San Jose State University, Johns Hopkins University, The University of Sydney, The University of Texas at Dallas, University of California, San Francisco, UCSF Edward and Pearl Fein Memory and Aging Center, University of Toronto, Baycrest Academy for Research and Education, Max Planck Institute for Human Development, Stony Brook University, University of Maryland, College Park, Baycrest Hospital, Rotman Research Institute, University of Pennsylvania, Wayne State University
Language: English
Subfield: Computer Vision and Pattern Recognition
Field: Computer Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,780
Funders: U.S. Department of Defense, Alzheimer's Association, Bristol-Myers Squibb, Eli Lilly and Company, Pfizer, Biogen, University of Southern California, F. Hoffmann-La Roche, Meso Scale Diagnostics, Alzheimer's Disease Neuroimaging Initiative, BioClinica, Novartis Pharmaceuticals Corporation, Northern California Institute for Research and Education, Lunds Universitet, Eisai, Servier, H. Lundbeck A/S, FONDATION ALZHEIMER, IXICO, Région Normandie, Fondation Philippe Chatrier, Fondation pour la Recherche sur Alzheimer, National Institutes of Health, Genentech, Canadian Institutes of Health Research, National Institute on Aging, National Institute of Mental Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development
Awards: G100845555, G1012222616, G104586243, G1298807586, G1554142629, G1593117279, G1650819308, G1880935189, G1928361401, Alzheimer's Disease Neuroimaging Initiative, G2100670906, G2105457377, G2152643862, G2189010064, G2302581481, G2340207221, G2423387114, G2471646051, G2522063444, G2835601961, G29951154, G3131374986, G3146424788, G3216574877, G3512028809, G3553156159, G3710456697, G3752451908, G3870774570, G3908963977, G3966393351, G4119534169, G43180419, G4475667458, G4501223628, G4800177743, G484628225, G5207404921, G5209990037, G528601746, G5365730499, EFFECTS OF TRAUMATIC BRAIN INJURY (TBI) AND POST TRAUMATIC STRESS DISORDER (PTSD) ON ALZHEIMER'S DISEASE (AD) IN VETERANS USING IMAGING AND BIOMARKERS IN THE AD NEUROIMAGING INITIATIVE (ADNI)", G5642834341, G5654639750, Alzheimer's Disease Neuroimaging Initiative, G5740349702, G5850682332, G613619302, G6173816828, G6210868510, G6371410416, G6412110892, G6447063303, Neural Correlates and Modifiers of Cognitive Aging, G6719828067, G6792506723, G6899163935, G6948409098, An integrative multisite study of the influence of socioeconomic disparities on hippocampal subfields developmental trajectories, G72415811, G7298697282, Ex Vivo Imaging of the Aging Brain to Discover Morphology/Pathology Associations, G764699806, Hippocampal-Memory Network Development and Episodic Memory in Early Childhood, G7799614282, G781725486, G8228018387, G8281378126, G839208290, G8852128998, G8895907669, G8897063270, G8957659042, G9000039018, G9000068296, G9000122335, G9000144445, Michigan Alzheimer's Disease Research Center, Development of Memory Networks in Children, Improving the sensitivity and specificity of MRI-based biomarkers in Alzheimer's disease, A harmonized medial temporal lobe subregion segmentation protocol: an essential element for dementia research, Influences of Environmental Geometry and Aging on Cognitive Mapping Mechanisms, The Alzheimer's Disease Research Center at the University of California, Irvine
OpenAlex ID: W7223372298