Fig. 2

Typical examples of combined index maps IDf and index maps IADC, ID and If. Index maps were displayed as two-colour b800 overlay. Moreover, the related subtracted contrast-enhanced arterial phase T1-weighted images (DCE) and the original diffusion-weighted images with b = 0, 50, 800 s/mm² (b0, b50, b800) are given. Lesions were assessed in the translucent hyperintense areas (marked in the b800 image with yellow arrowheads). For (a) an invasive ductal breast carcinoma (around 2.3 × 2.2 cm, grading G3), (b) an invasive lobular breast carcinoma (around 1.4 × 1.0 cm, grading G2), and (d) an invasive ductal breast carcinoma (around 2.3 × 2.2 cm, grading unknown), ID index maps show predominantly red voxels and If and IDf show clearly perfusion hot spots, indicating malignancy. For (c) a high grade lobular carcinoma in situ (LIN III, at least 5 cm in size, grading G2), ID index maps show predominantly red voxels and If and IDf show partially small perfusion hot spots at the edges (more than one row of red voxels), indicating also malignancy. For (e) a complicated cyst (around 0.8 × 0.6 cm), ID index maps show falsely malignancy, but due to the absence of any hot spots (only one row of red voxels at the edge do not count as hot spot), IDf classifies the lesion correctly as benign. In general, all liquid-filled lesions/compartments with low diffusion coefficient can be differentiated from malignant lesions by the uniformly low perfusion fraction.