Quantification of iron-labeled cells with positive contrast in mouse brains

Mol Imaging Biol. 2011 Aug;13(4):672-8. doi: 10.1007/s11307-010-0402-1. Epub 2010 Aug 24.


Purpose: To quantify small amounts of iron-labeled cells in mouse brains with magnetic resonance imaging (MRI).

Procedures: Iron-labeled cells (from 500 to 7,500) were stereotaxically transplanted into the brain of living mice that were subsequently imaged with MRI at 4.7 T. We compared four quantitative methods: (1) T2 relaxometry, (2) T2* relaxometry, (3) the volume of the cloverleaf hypointense artifact generated on T2*-weighted images, and (4) the volume of the cloverleaf hyperintense artifact generated on positive contrast images.

Results: The methods based on relaxometry, whether T2 or T2*, did not correlate with the number of injected cells. By contrast, those based on measurement of cloverleaf artifact volume, whether using negative or positive enhancement, showed a significant linear relationship for the given range of cells (R [0.92-0.95], p < 0.05).

Conclusions: T2* artifact volume imaging (negative or positive) appears promising for the quantification of magnetically labeled cells following focal injection in the brain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Artifacts
  • Brain / cytology*
  • Brain / metabolism*
  • Contrast Media / metabolism*
  • Female
  • Ferric Compounds / metabolism
  • Image Processing, Computer-Assisted
  • Iron / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Nanoparticles / chemistry
  • Staining and Labeling / methods*


  • Contrast Media
  • Ferric Compounds
  • ferric oxide
  • Iron