Figure 7: Multimodal imaging of neural progenitor cells (NPCs). Displayed are data from one representative animal with injection of NPCs within a preestablished glioma (a) and from one representative animal with injection of NPCs mixed with glioma cells (b). Upper row, BLI signal over the brain at 0, 2, 5, 9, and 13 days, respectively 0, 5, 13, and 15 days postimplantation. Second row, Gadolinium-enhanced T1 MRI at 7 days posttransplantation. The cross focuses on the growing glioma. Lower rows, 18F-FHBG PET image at 7 and 13 days posttransplantation, matched to the MRI displayed in the second row. After 150 minutes of tracer incubation, specific 18F-FHBG accumulation is visible at the site of glioma proliferation in both injection paradigms ((a) and (b)). The BLI signal intensity increases between days 5 and 15 in the mixed injection paradigm which is also reflected in an increased 18F-FHBG uptake between days 7 and 13 (b).