Figure 1.

Low-frequency repetitive transcranial magnetic stimulation (rTMS)-induces blood–brain barrier (BBB) opening is time-dependent. (A). Fluorescent angiography of the right, exposed motor cortex of the rat, overlaid with extravascular permeability index (see Section 2), at baseline (left) and 15 min from low-frequency rTMS onset (right). (B). Detection of BBB dysfunction (BBBD). Fluorescent angiography, at 15 min from TMS onset, overlaid with detection of extravascular pixels (red) in which permeability has changed from baseline in >3 standard deviations of the mean change seen following sham stimulation [27]. Magnification is identical to (A). (C). Similar analysis as in B, performed for 30 min (left) and 120 min (right) from TMS onset. (D). Mean ± squared error of the mean (SEM) change in permeability index relative to baseline for 15 [27], 30, and 120 min from TMS onset. ** p < 0.01.