Figure 18b. T1 adenocarcinoma of the lung with brain metastasis in a 52-year-old man. (a) Transaxial thin-section (1-mm collimation) CT scan (lung window) obtained at the level of the left upper lobar bronchus shows a 19-mm nodule with a spiculated margin in the left upper lobe. (b) Transaxial gadolinium-enhanced T1-weighted MR image shows metastatic nodules in the right parietal and occipital lobes (arrows).