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).
Conclusion: Certified benchmark labels have been produced based on the HarP to be used for tracers' training and qualification.
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.
Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.