Fig. 1: Tumor oxygenation and hemoglobin are reduced overtime and inversely correlate with tumor growth.

a Ultrasound-photoacoustic assisted imaging of heterotopic GBM showing representative 2D frames tumor mass, oxygen saturation, total hemoglobin and 3D reconstruction of tumor mass at 20 and 30 dpg. b–c Quantification of oxygen saturation and total hemoglobin levels within the tumor mass at 20 (white boxes and white circle) and 30 (blue boxes and blue circle) dpg. d Biplot of the percentage of oxygen saturation and tumor volume expressed in mm3. *p-value < 0.05 and **p-value<0.01. HB hemoglobin, dpg: days post-graft.