Fig. 3

A 2-D schematic of a cubic lattice used to evaluate the detailed pO₂ profile in a tumor and the virtual grid to simulate the voxels from in vivo functional imaging modality. a The cubic lattice structure (blue diamonds) is used to calculate the pO2 value using Green’s function algorithm, where the edge length of the lattice is 15 µm. A 200-µm virtual grid is superimposed over the tumor. The color of the vessel segment indicates the geometrical relation of the vessel segment to the voxel. Green vessel segments are located entirely within the voxel; yellow segments represent vessels that cross two voxels; and blue segments are located outside the grid. b An example of a 100-µm virtual grid of the same tumor is displayed for comparison