Fig. 8

Pulmonary metastases. A 69-year-old female, with a history of breast cancer diagnosed 9 years prior, shows a hypermetabolic nodule in the inferior lobe of the right lung on PET/CT. A biopsy reveals a metastasis of a ductal mammary carcinoma. An RF ablation is performed. Imaging of the lesion 1 day before (first column), 24 h after (second column), and 3 months after (third column) complete RF ablation is performed. Before ablation, an 8-mm well-circumscribed nodule is depicted on the synthesised monochromatic 70-keV lung window, FDG-avid on the PET scan (white arrows). Internal vascularisation is clearly observable on the contrast-enhanced, synthesised monochromatic 40-keV, greyscale- and colour-coded iodine images (circles). The changes found 24 h post ablation are a ground-glass appearance (yellow arrowheads) around the lesion and the vanishing of the previously seen iodine uptake in the lesion. The post-ablative avascular zone surrounding the necrotic lesion can be delineated on the iodine images as darker areas (yellow arrows). On the lung window images after 3 months, the treated area has transformed into a homogeneous, well-delineated area of high attenuation. PET/CT images reveal no activity after the RF ablation. The greyscale- and colour-coded iodine images show a reduction in size of the avascular region