Hironobu Yasui1,2, Shingo Matsumoto1,
Jeeva P. Munasinghe3, Nallathamby Devasahayam1,
Sankaran Subramanian1, James B. Mitchell1, Murali C.
Krishna1
1National Cancer Institute, Bethesda,
MD, United States; 2Hokkaido University, Hokkaido, Japan; 3National
Institute of Neurological Disorder and Stroke
Structural
and functional abnormality of blood vessels within malignant tumors
influences delivery of oxygen, a key radio-sensitizer, resulting in two
different types of hypoxia. Chronic hypoxia is attributed to large diffusion
distances between tumor microvessels and longitudinal oxygen gradient,
whereas acute hypoxia is though to be the result of transient vascular
occlusion and fluctuation in red blood cell flux. Electron paramagnetic
resonance (EPR) imaging is a sensitive method to non-invasively map tissue
oxygenation distribution. To investigate the fluctuation of tumor oxygen
concentration, dynamic 3D EPR oxygen imaging was applied to two different
types of tumor bearing in mouse.
Keywords