How In Vivo EPR Measures and Images Oxygen

  • Boris Epel
  • Gage Redler
  • Howard J. Halpern
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 812)


The partial pressure of oxygen (pO2) in tissues plays an important role in the pathophysiology of many diseases and influences outcome of cancer therapy, ischemic heart and cerebrovascular disease treatments and wound healing. Over the years a suite of EPR techniques for reliable oxygen measurements has been developed. This is a mini-review of pulse EPR in vivo oxygen imaging methods that utilize soluble spin probes. Recent developments in pulse EPR imaging technology have brought an order of magnitude increase in image acquisition speed, enhancement of sensitivity and considerable improvement in the precision and accuracy of oxygen measurements.


EPR Imaging Oxygen Relaxation 



Supported by NIH grants P41 EB002034 and R01 CA98575.


  1. 1.
    Eastman PE, Kooser RG, Pas MR, Freed JH (1969) Studies of Heisenberg spin exchange in ESR spectra I. Linewidth and saturation effects. J Chem Phys 54(2690)Google Scholar
  2. 2.
    Tatum JL et al (2006) Hypoxia: Importance in tumor biology, noninvasive measurement by imaging, and value of its measurement in the management of cancer therapy. Int J Radiat Biol 82:699–757CrossRefPubMedGoogle Scholar
  3. 3.
    Ardenkjaer-Larsen JH et al (1998) EPR and DNP properties of certain novel single electron contrast agents intended for oximetric imaging. J Magn Reson 133:1–12CrossRefPubMedGoogle Scholar
  4. 4.
    Williams BB et al (2002) Imaging spin probe distribution in the tumor of a living mouse with 250 MHz EPR: correlation with BOLD MRI. Magn Reson Med 47:634–638CrossRefPubMedGoogle Scholar
  5. 5.
    Matsumoto K et al (2004) Pharmacokinetics of a triarylmethyl-type paramagnetic spin probe used in EPR oximetry. Magn Reson Med 52:885–892CrossRefPubMedGoogle Scholar
  6. 6.
    Krishna MC et al (2002) Overhauser enhanced magnetic resonance imaging for tumor oximetry: coregistration of tumor anatomy and tissue oxygen concentration. Proc Natl Acad Sci U S A 99:2216–2221CrossRefPubMedPubMedCentralGoogle Scholar
  7. 7.
    Williams BB, Pan XC, Halpern HJ (2005) EPR imaging: the relationship between CW spectra acquired from an extended sample subjected to fixed stepped gradients and the Radon transform of the resonance density. J Magn Reson 174:88–96CrossRefPubMedGoogle Scholar
  8. 8.
    Deans SR (1983) The radon transformation and some of its applications. John Wiley & Sons, New YorkGoogle Scholar
  9. 9.
    Ahn KH, Halpern HJ (2007) Spatially uniform sampling in 4-D EPR spectral-spatial imaging. J Magn Reson 185:152–158CrossRefPubMedGoogle Scholar
  10. 10.
    Ahmad R et al (2007) Enhanced resolution for EPR imaging by two-step deblurring. J Magn Reson 184:246–257CrossRefPubMedGoogle Scholar
  11. 11.
    Maresch GG, Mehring M, Emid S (1986) High-resolution electron-spin-resonance imaging. Physica B C 138:261–263CrossRefGoogle Scholar
  12. 12.
    Subramanian S et al (2002) Single-point (constant-time) imaging in radiofrequency Fourier transform electron paramagnetic resonance. Magn Reson Med 48:370–379CrossRefPubMedGoogle Scholar
  13. 13.
    Devasahayam N et al (2007) Strategies for improved temporal and spectral resolution in in vivo oximetric imaging using time-domain EPR. Magn Reson Med 57:776–783CrossRefPubMedGoogle Scholar
  14. 14.
    Matsumoto K et al (2006) Electron paramagnetic resonance imaging of tumor hypoxia: enhanced spatial and temporal resolution for in vivo pO(2) determination. Magn Reson Med 55:1157–1163CrossRefPubMedGoogle Scholar
  15. 15.
    Mailer C, Sundramoorthy SV, Pelizzari CA, Halpern HJ (2006) Spin echo spectroscopic electron paramagnetic resonance imaging. Magn Reson Med 55:904–912CrossRefPubMedGoogle Scholar
  16. 16.
    Epel B, Sundramoorthy SV, Mailer C, Halpern HJ (2008) A versatile high speed 250-MHz pulse imager for biomedical applications. Conc Magn Reson B 33B:163–176CrossRefGoogle Scholar
  17. 17.
    Subramanian S et al (2012) Echo-based single point imaging (ESPI): a novel pulsed EPR imaging modality for high spatial resolution and quantitative oximetry (San Diego, CA: 1997). J Magn Reson 218:105–114CrossRefPubMedGoogle Scholar
  18. 18.
    Epel B, Bowman MK, Mailer C, Halpern HJ (2013) Absolute oxygen R1e imaging in vivo with pulse electron paramagnetic resonance. Magnet Reson Med. Epub ahead of printGoogle Scholar
  19. 19.
    Gallez B, Baudelet C, Jordan BF (2004) Assessment of tumor oxygenation by electron paramagnetic resonance: principles and applications. NMR Biomed 17:240–262CrossRefPubMedGoogle Scholar
  20. 20.
    Swartz HM, Clarkson RB (1998) The measurement of oxygen in vivo using EPR techniques. Phys Med Biol 43:1957–1975CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2014

Authors and Affiliations

  • Boris Epel
    • 1
    • 2
  • Gage Redler
    • 1
    • 2
  • Howard J. Halpern
    • 1
    • 2
    • 3
  1. 1.Center for EPR Imaging In Vivo PhysiologyChicagoUSA
  2. 2.Department of Radiation OncologyUniversity of ChicagoChicagoUSA
  3. 3.MC1105, Department of Radiation and Cellular OncologyUniversity of Chicago Medical CenterChicagoUSA

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