Figure 5. Tumours with a greater relative blood volume were more likely to respond to chemotherapy than those with a lower or no recordable blood volume. The top images (a and c) are the T₂ weighted axial anatomical images of the tumours and the lower two images are the relative blood volume or "susceptibility" maps. The "susceptibility" maps arise from a first pass effect of contrast agent through the tumour inducing a susceptibility effect. Although the physical effect is manifest as a signal loss, the scale has been inverted to highlight the areas of signal loss. The tumour illustrated on the left (a and b) demonstrates a strong "susceptibility" effect whilst there was no recordable signal loss in the tumour on the right (c and d). The tumour on the right is less likely to respond to chemotherapy than the one on the right.