*2.11. Computed Tomography*

The mice were anesthetized with ketamine and xylazine (80 and 10 mg/kg, respectively) and subjected to computed tomography (PET-SPECT and CT-Bruker, Ettlingen, Germany). It used low-resolution (CT single good, low dose (200 µA), low voltage (35 µA)), and standard CT quality. Two hundred and fifty image projections were collected per animal with three minutes of exposure. Then, images were reconstructed with standard software reconstruction modes to evaluate the pulmonary radiopacity profile and bone structure. The pulmonary radiopacity profile was assessed in all planes of the image by delimiting the pulmonary region using the inner side of the rib cage as a reference. The software generates an automatic Hounsfield (HU) scale, and the voxel (3D pixel) intensity values create a Gaussian distribution in this HU scale. The less-dense voxels on the scale are positioned on the left, while the denser ones are placed on the right. Increased pulmonary density, which is correlated with lung metastasis [6], was evaluated by the Gaussian curve displacement to the right. The area under the curve of each experimental animal was calculated as the integral of the curve in a bar graph.
