3D inversion recovery ultrashort echo time MRI can detect demyelination in cuprizone-treated mice

Adam C Searleman1, Yajun Ma1, Srihari Sampath1

  • 1Department of Radiology, University of California, San Diego, San Diego, CA, United States.

PubMed
Abstract

Insights

Inversion-recovery ultrashort echo time (IR-UTE) MRI effectively detected demyelination in mice. This novel MRI technique shows promise for noninvasively measuring brain myelin content.

Area of Science:

  • Neuroimaging
  • Biomedical Engineering
  • Demyelinating Diseases

Background:

  • Conventional MRI struggles to detect myelin due to ultrashort T2 relaxation times of non-aqueous myelin protons.
  • Ultrashort echo time (UTE) sequences can detect these myelin signals.
  • Inversion-recovery preparation in IR-UTE MRI suppresses water signals, isolating myelin components.

Purpose of the Study:

  • To evaluate the efficacy of inversion-recovery ultrashort echo time (IR-UTE) MRI in directly detecting demyelination.
  • To utilize a standard cuprizone mouse model for assessing demyelination.
  • To establish IR-UTE MRI as a method for measuring brain myelin content.

Main Methods:

  • Eight 8-week-old C57BL/6 mice were divided into cuprizone (n=4) and control (n=4) groups.
  • Mice received cuprizone or control chow for 5 weeks.
  • 3D IR-UTE MRI was performed, and signal differences in white matter tracts were analyzed and correlated with Luxol Fast Blue staining.

Main Results:

  • IR-UTE MRI signal significantly decreased in demyelination-sensitive white matter areas (e.g., corpus callosum) of cuprizone-treated mice.
  • No significant signal change was observed in demyelination-resistant white matter areas (e.g., internal capsule).
  • These MRI findings showed strong correlation with histochemical myelin staining results.

Conclusions:

  • 3D IR-UTE MRI is sensitive to cuprizone-induced demyelination in the mouse brain.
  • This technique offers a promising noninvasive approach for quantifying brain myelin content.
  • IR-UTE MRI has potential applications in studying demyelinating diseases.