Fig. 3.
Dual-contrast MRI of lymph node metastases. a & b Unenhanced T1-weighted MRI with fast low-angle shot (FLASH) sequence. c & d Unenhanced T2-weighted MRI with tuber fast spin echo sequence. e T1-weighted MRI immediately after administration of Gd-DTPA. f T2-weighted MRI at 30 min after iron oxide nanoparticles administration. g T2-weighted dual contrast MRI with Gd-DTPA first then IO. h T2-weighted dual contrast MRI with IO first then Gd-DTPA. i Contrast-to-noise (C/N) ratios calculated based on the signal intensity over the lymphatic tissue and metastatic tumor tissue. j & k, Prussian blue staining of lymphatic tissue (j) and metastatic tumor tissue (k) within the lymph node.