An In vivo Multi-Modal Structural Template for Neonatal Piglets Using High Angular Resolution and Population-Based Whole-Brain Tractography
An increasing number of applications use the postnatal piglet model in neuroimaging studies, however, these are based primarily on T1 weighted image templates. There is a growing need for a multimodal structural brain template for a comprehensive depiction of the piglet brain, particularly given the growing applications of diffusion weighted imaging for characterizing tissue microstructures and white matter organization.
In this study, we present the first multimodal piglet structural brain template which includes a T1 weighted image with tissue segmentation probability maps, diffusion weighted metric templates with multiple diffusivity maps, and population-based whole-brain fiber tracts for postnatal piglets.
These maps provide information about the integrity of white matter that is not available in T1 images alone. The availability of this diffusion weighted metric template will contribute to the structural imaging analysis of the postnatal piglet brain, especially models that are designed for the study of white matter diseases. Furthermore, the population-based whole-brain fiber tracts permit researchers to visualize the white matter connections in the piglet brain across subjects, guiding the delineation of a specific white matter region for structural analysis where current diffusion data is lacking. Researchers are able to augment the tracts by merging tracts from their own data to the population-based fiber tracts and thus improve the confidence of the population-wise fiber distribution.
Figure 1. First 3 columns show tissue probability maps for white matter (WM), gray matter (GM) and cerebrospinal fluid (CSF) in the template space. Template T1 image is shown in the axial, sagittal and coronal views in column 4.
Figure 2. Diffusion metric templates with AD and FA maps are shown in the axial, sagittal and coronal views.
Figure 3. Merged whole-brain fiber tracts are shown from the top view. Brighter color represents higher values.
Figure 4. Merged whole-brain fiber tracts are shown in the sagittal view. Brighter color represents higher values.
This study is publshed in Frontiers Neuroanatomy 2016; 10: 92, doi: 10.3389/fnana.2016.00092. For more information please head over to the paper.