Pulmonary nodule enhancement in subtraction CT and dual-energy CT: A comparison study

Abstract Objective To compare nodule enhancement on subtraction CT iodine maps to that on dual-energy CT iodine maps using CT datasets acquired simultaneously. Methods A previously-acquired set of lung subtraction and dual-energy CT maps consisting of thirty patients with 95 solid pulmonary nodules (≥4 mm diameter, 72 malignant) was used. Nodules were annotated and segmented on CT angiography, and mean nodule enhancement in the iodine maps calculated. Three radiologists scored nodule visibility with both techniques on a 4-point scale. Results Mean nodule enhancement was higher (p  Conclusions Subtraction CT is able to depict iodine enhancement in pulmonary nodules better than dual-energy CT.