FIGURE 2.

Multimodality assessment of toxicity. Toxicity of the cell infusion (stroke) was assessed by angiography, MRI, and necropsy. These are shown in the positive control subjects 7 and 8. A, Angiography demonstrating contrast stagnation and subtracted vascular cast of the brain caused by radio-opaque embolic particle injection. This demonstrates the expected appearance and detectability of large vessel stroke by angiography. The result was most dramatic in subject 8, shown here, with complete occlusion of the right, demonstrating our ability to identify angiographic occlusion in this animal model. B, MRI Brain, FLAIR sequence demonstrating diffuse sulcal effacement and gray-white matter blurring. The paired ADC sequence shows diffusely low ADC signal. C, In all sections of the cerebrum and midbrain examined there were numerous intravascular, spherical, laminated foreign bodies approximately 40-100 microns in diameter; these were seen especially along the middle cerebral artery and in small arterioles. While the vessels were occluded, histological development of stroke was not yet observed.