Materials

We extend upon the work described in Bozek et. al (2018) to provide age-specific symmetric cortical surface atlases from 28 to 44 weeks’ postmenstrual age. These new templates differ from the previous release in that there is vertex-wise correspondence, in cortical folding, between the left and right hemispheres for each age-specific template. This space is referred to as dhcpSym space.

For each age-specific template, we provide the template in its own local symmetric space (dhcpSym) and the template in 40-week symmetric space (dhcpSym40). Files are named using BIDS conventions, and are as follows:

  • week: postmenstrual age of template
  • hemi:  left or right hemisphere
  • space: dhcpSym (local template space) or dhcpSym40 (40-week template space)
  • dens: number of vertices

Template metric files contained in this release are:

  • myelinmap.shape.gii: T1/T2 ratio
  • sulc.shape.gii: sulcal depth
  • thickness.shape.gii: cortical thickness

Template surface files contained in this release are:

  • midthickness.surf.gii: midthickness
  • pial.surf.gii: pial
  • sphere.surf.gii: sphere
  • vinflated.surf.gii: very inflated
  • wm.surf.gii: white matter

As examples:

  • The sulcal depth template for the 28-week left hemisphere in local template space is named ‘week-28_hemi-left_space-dhcpSym_dens-32k_sulc.shape.gii’
  • The white matter surface template for the 28-week left hemisphere in local template space is named ‘week-28_hemi-left_space-dhcpSym_dens32k_wm.surf.gii’

Methods

Generation of the symmetric template was generated as follows:

  1. Using data from the third dHCP release, the asymmetric Bozek et. al (2018) surface atlas was extended from 36-44 to 28-44 weeks’ postmenstrual age.
  2. Using MSM, the left and right hemispheres from each week of the extended Bozek et. al (2018) atlas were co-registered in order to generate left-right vertex correspondence of coarse scale patterns of cortical folding (sulcal depth). Registration was run in left-to-right (forward) and right-to-left (reverse) directions.
  3. Deformation maps of the forward and inverse of the reverse registrations were averaged to generate an intermediate symmetric template space. Local non-symmetric template metrics and anatomical meshes were resampled into their corresponding symmetric template (dhcpSym).
  4. Consecutive registrations between local symmetric templates were then performed to achieve a local to 40-week registration deformation. A further resampling step was performed to produce local metric and anatomical meshes in 40-week symmetric space (dhcpSym40).

References:

  1. Robinson, E. C., Garcia, K., Glasser, M. F., Chen, Z., Coalson, T. S., Makropoulos, A., … & Rueckert, D. (2018). Multimodal surface matching with higher-order smoothness constraints. Neuroimage, 167, 453-465.
  2. Bozek, J., Makropoulos, A., Schuh, A., Fitzgibbon, S., Wright, R., Glasser, M. F., … & Robinson, E. C. (2018). Construction of a neonatal cortical surface atlas using Multimodal Surface Matching in the Developing Human Connectome Project. NeuroImage, 179, 11-29.
  3. Williams, L. Z. J., Fitzgibbon, S. P., Cupitt, J., Dimitrova, R., Poppe, T., Bozek, J, Schuh, A, Makropoulos, A, J, O’Muircheartaigh, J, Duff, E. P., Rueckert, D., Hajnal, J. V., Smith, S. M., Edwards, A. D., & Robinson, E. C. Structural and functional asymmetry in the neonatal cerebral cortex. In preparation.

Download

You can download the atlas from here.