Fig. 3.

In vivo Detection of BBB permeability by EB staining. (a) MRI image of GBM-bearing mouse brain at Day 7. (b) PA image of the brain cortex acquired in the yellow dashed box of (a) by PAM at 24 h after EB injection. The diffuse signal indicated EB extravasation from the vessels. Less EB staining was evident in the brain tissue. (c) PA amplitude profile of (b). (d) Photograph of ex vivo brain tissues. (e-h) Corresponding results of GBM-bearing mouse brain at Day 18. Areas of “bluing” in photos represent that the vascular permeability to EB-albumin complex increased with tumor progression. (i) PA images of the mice in the early-stage group. (j) PA images of the mice in the middle-stage group. (k) PA images of the mice in the advanced-stage group.