Article

A high-resolution computational atlas of the human hippocampus from postmortem magnetic resonance imaging at 9.4 T

Penn Image Computing and Science Laboratory (PICSL), Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
NeuroImage (Impact Factor: 6.36). 10/2008; 44(2):385-98. DOI: 10.1016/j.neuroimage.2008.08.042
Source: PubMed

ABSTRACT This paper describes the construction of a computational anatomical atlas of the human hippocampus. The atlas is derived from high-resolution 9.4 Tesla MRI of postmortem samples. The main subfields of the hippocampus (cornu ammonis fields CA1, CA2/3; the dentate gyrus; and the vestigial hippocampal sulcus) are labeled in the images manually using a combination of distinguishable image features and geometrical features. A synthetic average image is derived from the MRI of the samples using shape and intensity averaging in the diffeomorphic non-linear registration framework, and a consensus labeling of the template is generated. The agreement of the consensus labeling with manual labeling of each sample is measured, and the effect of aiding registration with landmarks and manually generated mask images is evaluated. The atlas is provided as an online resource with the aim of supporting subfield segmentation in emerging hippocampus imaging and image analysis techniques. An example application examining subfield-level hippocampal atrophy in temporal lobe epilepsy demonstrates the application of the atlas to in vivo studies.

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    • "The final reconstructed and aligned bSSFP volumes were visualized using ITK-SNAP (www.itksnap.org). Segmentation of hippocampal subregions was performed manually according to anatomic atlases and our prior work (Duvernoy, 2005; Insausti and Amaral, 2008; Yushkevich et al., 2009; Zeineh et al., 2012). Detailed hippocampal subfield segmentation was performed of the hippocampal body only, not the tail or head. "
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    NeuroImage 02/2015; 112. DOI:10.1016/j.neuroimage.2015.02.029 · 6.36 Impact Factor
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    01/2015; 3(1). DOI:10.1080/21681163.2014.933679
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    • "Integration of data from myelin-stained (Geyer et al., 2011) sections of postmortem hippocampus into probabilistic atlases may greatly improve the reliability of hippocampal subregional boundary determinations. Future studies may benefit from the combination of computational unfolding, ROI analysis, MVPA (Bonnici et al., 2012), histology guided segmentation approaches (Adler et al., 2014), cytoarchitectural postmortem atlases (Yushkevich et al., 2009), high-field structural imaging (Mueller et al., 2007; Zeineh et al., 2014), and automated segmentation procedures (Van Leemput et al., 2009, Yushkevich et al., 2010, 2014) in order to provide a complete, accurate, and fast analysis of structural and functional imaging studies of human hippocampal subfields during normal memory and disorders such as Alzheimer's disease or temporal-lobe epilepsy. Our results summarize our recent improvements in high-resolution imaging and computational unfolding methods of the human hippocampus in vivo. "
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