“…Physical modalities, such as noninvasive microbubble-enhanced focused ultrasound (MB-FUS) ( Figure 3 ), can safely and transiently alter the permeability of the BBB/BTB without directly causing changes in the tumor cells. This technology has been demonstrated preclinically in numerous species, including nonhuman primates [ 3 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 ], and in multiple successful Phase I and IIa clinical trials executed by several different groups [ 4 , 5 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 ]. Ultrasound-mediated BBB disruption has been observed in normal brains [ 3 , 124 ], brains affected by neurodegenerative diseases (e.g., Parkinson′s disease and Alzheimer′s disease) [ 123 ], and brains with tumors [ 4 , 5 , 6 ].…”