Figure 17

MRI of mouse bladder using Gd-Cy5.5 as contrast agent. A. Gray-scale image of the bladder and tumors at pre-contrast before Gd-probe administration. B. Difference image obtained at 30 minutes post-Gd-probe contrast subtracted from the pre-contrast image. This image demonstrates an early enhancement by the contrast agent into the urinary bladder extravascular space, which may be attributed to vascular leakage. C. Difference image obtained at 80 minutes post-contrast subtracted from 30 minutes post-contrast. This image demonstrates a delayed enhancement due to drainage and pooling of the contrast agent, which may reflect uptake within the lymphatics in the bladder. D. Difference image obtained between images in B and C (80 min. post-contrast minus 30 min post-contrast, and the 30 min. post-contrast minus the pre-contrast images). This image suggests that there is decreased drainage within tumorigenic areas, and perhaps a pronounced increase in uptake in the lymphatics within normal regions.