3. Numerous bronchial-associated ground glass opacities
The thoracic CT scan is clearly abnormal with numerous rounded densities most of which have a bronchus in the center. The bronchi are well preserved and this would favor an acute pneumonitis over metastatic carcinoma although this is not diagnostic. A mosaic pattern is produced with interlobular and intralobular septal thickening (see July 2015 Pulmonary Case of the Month: A Crazy Case for an example). The halo sign occurs when a solid nodule is surrounded by a ground-glass opacity (see September 2015 Imaging Case of the Month for an example).
What is the best next step in evaluating the patient? (Click on the correct answer to proceed to the third of four pages)