Neuroanatomical underpinning of diffusion kurtosis measurements in the cerebral cortex of healthy macaque brains

Magn Reson Med. 2021 Apr;85(4):1895-1908. doi: 10.1002/mrm.28548. Epub 2020 Oct 15.


Purpose: To investigate the neuroanatomical underpinning of healthy macaque brain cortical microstructure measured by diffusion kurtosis imaging (DKI), which characterizes non-Gaussian water diffusion.

Methods: High-resolution DKI was acquired from 6 postmortem macaque brains. Neurofilament density (ND) was quantified based on structure tensor from neurofilament histological images of a different macaque brain sample. After alignment of DKI-derived mean kurtosis (MK) maps to the histological images, MK and histology-based ND were measured at corresponding regions of interests characterized by distinguished cortical MK values in the prefrontal/precentral-postcentral and temporal cortices. Pearson correlation was performed to test significant correlation between these cortical MK and ND measurements.

Results: Heterogeneity of cortical MK across different cortical regions was revealed, with significantly and consistently higher MK measurements in the prefrontal/precentral-postcentral cortex compared to those in the temporal cortex across all six scanned macaque brains. Corresponding higher ND measurements in the prefrontal/precentral-postcentral cortex than in the temporal cortex were also found. The heterogeneity of cortical MK is associated with heterogeneity of histology-based ND measurements, with significant correlation between cortical MK and corresponding ND measurements (P < .005).

Conclusion: These findings suggested that DKI-derived MK can potentially be an effective noninvasive biomarker quantifying underlying neuroanatomical complexity inside the cerebral cortical mantle for clinical and neuroscientific research.

Keywords: biomarker; cerebral cortex; diffusion MRI; diffusion kurtosis imaging; histology; microstructure.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Brain / diagnostic imaging
  • Cerebral Cortex / diagnostic imaging
  • Diffusion
  • Diffusion Magnetic Resonance Imaging
  • Diffusion Tensor Imaging*
  • Macaca*