Erratum: Detecting tumor response to treatment using hyperpolarized 13C magnetic resonance imaging and spectroscopySam E Day, Mikko I Kettunen, Ferdia A Gallagher, De-En Hu, Mathilde Lerche, Jan Wolber, Klaes Golman, Jan Henrik Ardenkjaer-Larsen & Kevin M BrindleNat. Med. 13, 1382–1387 (2007); published online 28 October 2007; corrected after print 12 November 2007.

In the version of this article initially published, Equation 2 is incorrect. The correct equation is:

Additionally, peak 1 in Figure 1a is incorrectly defined in the figure legend. Peak 1 represents the natural abundance of [2-13C]pyruvate.

The errors have been corrected in the HTML and PDF versions of the article.

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