title: Harmonized benchmark labels of the hippocampus on magnetic resonance: the EADC-ADNI project.
abstract: BACKGROUND
  A globally harmonized protocol (HarP) for manual hippocampal segmentation based on magnetic resonance has been recently developed by a task force from European Alzheimer's Disease Consortium (EADC) and Alzheimer's Disease Neuroimaging Initiative (ADNI). Our aim was to produce benchmark labels based on the HarP for manual segmentation.
  
  
  METHODS
  Five experts of manual hippocampal segmentation underwent specific training on the HarP and segmented 40 right and left hippocampi from 10 ADNI subjects on both 1.5 T and 3 T scans. An independent expert visually checked segmentations for compliance with the HarP. Descriptive measures of agreement between tracers were intraclass correlation coefficients (ICCs) of crude volumes and similarity coefficients of three-dimensional volumes.
  
  
  RESULTS
  Two hundred labels have been provided for the 20 magnetic resonance images. Intra- and interrater ICCs were >0.94, and mean similarity coefficients were 1.5 T, 0.73 (95% confidence interval [CI], 0.71-0.75); 3 T, 0.75 (95% CI, 0.74-0.76).
  
  
  CONCLUSIONS
  Certified benchmark labels have been produced based on the HarP to be used for tracers' training and qualification.
authors.affiliation: LENITEM (Laboratory of Epidemiology, Neuroimaging and Telemedicine), IRCCS-Centro S. Giovanni di Dio-Fatebenefratelli Brescia, Brescia, Italy; Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
authors.forename: Martina
authors.initials: M
authors.lastname: Bocchetta
authors.affiliation: LENITEM (Laboratory of Epidemiology, Neuroimaging and Telemedicine), IRCCS-Centro S. Giovanni di Dio-Fatebenefratelli Brescia, Brescia, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Boccardi
authors.affiliation: Department of Radiology, Université Laval and Centre de Recherche de l'Institut universitaire de santé mentale de Québec, Quebec City, Canada.
authors.forename: Rossana
authors.initials: R
authors.lastname: Ganzola
authors.affiliation: Mary S. Easton Center for Alzheimer's Disease Research and Laboratory of NeuroImaging, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
authors.forename: Liana G
authors.initials: LG
authors.lastname: Apostolova
authors.affiliation: Department of Diagnostic Radiology, Mayo Clinic and Foundation, Rochester, MN, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Preboske
authors.affiliation: Klinik für Psychiatrie und Psychotherapie, Johannes Gutenberg-Universität Mainz, Mainz, Germany.
authors.forename: Dominik
authors.initials: D
authors.lastname: Wolf
authors.affiliation: IRCCS-Centro S. Giovanni di Dio-Fatebenefratelli Brescia, Brescia, Italy.
authors.forename: Clarissa
authors.initials: C
authors.lastname: Ferrari
authors.affiliation: SeSMIT (Service for Medical Statistics and Information Technology), AFaR (Fatebenefratelli Association for Research), Fatebenefratelli Hospital, Rome, Italy; Unit of Clinical and Molecular Epidemiology, IRCCS "San Raffaele Pisana," Rome, Italy.
authors.forename: Patrizio
authors.initials: P
authors.lastname: Pasqualetti
authors.affiliation: Department of Radiology, Université Laval and Centre de Recherche de l'Institut universitaire de santé mentale de Québec, Quebec City, Canada.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Robitaille
authors.affiliation: Department of Radiology, Université Laval and Centre de Recherche de l'Institut universitaire de santé mentale de Québec, Quebec City, Canada.
authors.forename: Simon
authors.initials: S
authors.lastname: Duchesne
authors.affiliation: Department of Diagnostic Radiology, Mayo Clinic and Foundation, Rochester, MN, USA.
authors.forename: Clifford R
authors.initials: CR
authors.lastname: Jack
authors.affiliation: LENITEM (Laboratory of Epidemiology, Neuroimaging and Telemedicine), IRCCS-Centro S. Giovanni di Dio-Fatebenefratelli Brescia, Brescia, Italy; Memory Clinic and LANVIE - Laboratory of Neuroimaging of Aging, University Hospitals and University of Geneva, Geneva, Switzerland. Electronic address: gfrisoni@fatebenefratelli.it.
authors.forename: Giovanni B
authors.initials: GB
authors.lastname: Frisoni
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000473:pathology; D001284:Atrophy; D060825:Cognitive Dysfunction / Q000473:pathology; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D007318:Inservice Training / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D059906:Neuroimaging / Q000379:methods*; D009929:Organ Size; D015203:Reproducibility of Results
keywords: ADNI; Alzheimer's disease; Anatomic landmark; Harmonization; Harmonized protocol; Hippocampal atrophy; Hippocampal volume; Hippocampus; MRI; Manual tracing; Medial temporal lobes; Neuroimaging; Standard operating procedures