Figure 4

Lack of microscopic evidence of cell brain extravasations after modest BBBD procedures. A-C) When BBB disruption was not induced (see also Figure 2), cellular extravasation (as detected by Cresyl Violet) was limited to the Virchow-Robin space or to the proximity of superficial meninges. Modest and localized Gd⁺⁺extravasation was observed in the same regions. D-H) Cresyl Violet staining showed that parenchymal vessels were generally devoid of cellular extravasates. The reddish stain is indicative of hemoglobin accumulations in erythrocytes. Arrowhead indicates vessel in both BBBD and contralateral hemispheres. I) Small clusters of cells were infrequently observed in the proximity of vessels (asterisk).