T-1 relaxometry of crossing fibres in the human brain

Silvia de Santis*, Yaniv Assaf, Ben Jeurissen, Derek K. Jones, Alard Roebroeck

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

197 Downloads (Pure)


A comprehensive tract-based characterisation of white matter should include the ability to quantify myelin and axonal attributes irrespective of the complexity of fibre organisation within the voxel. Recently, a new experimental framework that combines inversion recovery and diffusion MRI, called inversion recovery diffusion tensor imaging (IR-DTI), was introduced and applied in an animal study. IR-DTI provides the ability to assign to each unique fibre population within a voxel a specific value of the longitudinal relaxation time, T-1, which is a proxy for myelin content. Here, we apply the IR-DTI approach to the human brain in vivo on 7 healthy subjects for the first time. We demonstrate that the approach is able to measure differential tract properties in crossing fibre areas, reflecting the different myelination of tracts. We also show that tract-specific T-1 has less inter-subject variability compared to conventional T-1 in areas of crossing fibres, suggesting increased specificity to distinct fibre populations. Finally we show in simulations that changes in myelination selectively affecting one fibre bundle in crossing fibre areas can potentially be detected earlier using IR-DTI.
Original languageEnglish
Pages (from-to)133-142
Number of pages10
Publication statusPublished - Nov 2016


  • Inversion recovery
  • DTI
  • Myelination
  • T-1

Cite this