Diffusion-weighted imaging of A11, S2, and U87 tumors before and after treatment. Representative T2-weighted axial slices from reference 1H images acquired at 9.4 T from an A11 tumor (A), S2 tumor (E), and U87 tumor posttreatment (I) at 7 days after treatment. The locations of the tumors are outlined by dotted black lines. Representative diffusion images, in false color, overlaid on the corresponding T2-weighted images acquired from A11 (B), S2 (F), and U87 (J) tumors before and at 48 hours and 7 days after the last chemoradiotherapy treatment. The locations of the tumors are outlined by dotted white lines. The underlying T2-weighted images acquired at 7 days after treatment are the same as those shown in A, E, and I and the underlying image shown in F at 48 hours posttreatment is the same as that shown in Fig. 3J. The 2H and diffusion-weighted images were acquired in the same imaging session as the T2-weighted images. Mean ADC measured along the slice-selective direction before and at 2 and 7 days after the last chemoradiotherapy treatment in A11 (n = 6; C), S2 (n = 6; G), and U87 (n = 6; K) tumors. Histograms of ADC values over all the animals imaged in A11 (D), S2 (H), and U87 (L) tumors. *, P < 0.05; ns, nonsignificant.