Figure 4.

In vivo visualization of heterogeneous BTB permeability in the same animal. Axial MR images of the mouse brain; tumor burden is shown in the bSSFP image (left), and BTB permeability associated with the tumors is indicated in the T1w SE post-Gd (right). Three tumors are visualized in the bSSFP image, yet only two are detectable in the T1w SE post-Gd. This suggests that Gd cannot cross the BTB associated with tumor 3 and demonstrates the difference in tumor detection using contrast-enhanced MRI compared to the bSSFP sequence.