Quantifying Tumor Vascular Heterogeneity with Dynamic Contrast-Enhanced Magnetic Resonance Imaging: A Review
Figure 2
Visual assessment of tumor vascular heterogeneity on a pseudocolor map is inherently subjective: the same parametric map of the pharmacokinetic parameter is visualized as pseudocolor overlays with different display ranges and color schemes on a morphologic image in a bladder cancer patient. Compared to the single color scheme ((a), “blackbody radiation”), the multicolor scheme “rainbow” in (b) exaggerates subtle differences in near color boundaries, creating artificial structures in the pseudocolor map. If the display range is chosen too large, the parametric map is perceived as being more “homogeneous” due to underrepresentation of the spatial variation (c). A small display range, on the other hand, tends to exaggerate the size of the “hotspot”, which may lead to an erroneous characterization of the disease (d).
