In vivo functional photoacoustic imaging of brain tumor vasculature

We present a study of the functional photoacoustic imaging of tumor hypoxia in mice in vivo. Based on spectroscopic photoacoustic tomography that detects the optical absorption of oxy- and deoxy-hemoglobins, the blood oxygen saturation and the vascularization of brain tumors were visualized. U87 glioblastoma tumor cells were inoculated intracranially at a 3-mm depth from the surface of the nude mouse head seven days before the experiment. Increased blood content and hypoxia inside the tumor vasculature were detected through the intact skin and skull. This technique will be useful for future studies on tumor metabolic activities in the brain and hypoxia-related therapeutic resistance