Figure 2

Lack of BBB opening can be detected radiologically or histologically. A-B) Example of an ineffective BBBD procedure. A low ineffective concentration of mannitol was used as control (non-BBBD, see methods). Radiological (MRI, T1) scans were similar before and after the BBBD procedure. Note the lack of Gd⁺⁺ signal in the scans taken after BBBD procedure, suggesting lack of cellular brain penetration. C-F) Ex-vivo, the absence of Evans Blue brain leakage further confirmed the lack of BBB opening in this animal. BBBD and contralateral sides were virtually identical. G-H) Perfusion scans and sagittal T1 sequences were taken after BBBD procedures to rule out the presence of gross anatomical alteration associated with the procedure.