Figure 2. Longitudinal MRI monitoring of the initiation and development of intracranial brain metastases.
A. MRI scans of the whole mouse brain were initiated 3 weeks after intracardiac injection of MDA-MB231Br cells and repeated once a week for 2 weeks. Four consecutive coronal MRI sections of a representative mouse brain showed no apparent intracranial lesions on T2-weighted images. However, follow-up images at week 4 identified multiple lesions with hyper-intensity on T2-weighted images (arrowhead), but none of them was enhanced on T1-weighted post contrast images. An increased number of lesions (arrowheads) appeared on the images at week 5, only a few of which (arrowheads) were enhanced post Gd-DTPA. B. Corresponding histological sections of H&E staining showed a good correlation with MRI. C. MRI evaluation of a total of 464 metastases in 9 mice brains indicated that these metastases distributed through the whole mouse brain with a higher incidence in the brain cortex (49%). Note: OB: Olfactory bulb; BG: Basal ganglia; Hippo: Hippocampus.