Correct!
3. The chest radiograph shows pulmonary cavities
A focal opacity is present within the left lower lobe, but it is not consolidation (i.e., homogeneous increased lung attenuation with obscuration of vascular and bronchial wall margins, often associated with air bronchograms); rather, the left lower lobe lesion is lucent centrally, consistent with a gas-containing lesion, or lung cavity. No pleural abnormalities are seen. Streaky perihilar opacities, consistent with airway thickening, are present bilaterally, but no discrete, tubular opacity associated with a nodule- a morphology suggestive of arteriovenous malformation- is seen. The lesion at the left base is near the location that would be expected for a diaphragmatic hernia, but this lesion is gas-containing, representing a pulmonary cavity, and is not solid-appearing, as would be expected for a diaphragmatic hernia. Furthermore, a diaphragmatic hernia will usually obscure the diaphragm contour where the diaphragmatic defect is located, creating an incomplete border sign (typical of a lesion outside the lung parenchyma); however, on this image, the entire circumference of the left lower lobe cavity is visible, indicating that it is completely surrounded by air.
The patient subsequently underwent thoracic CT (Figure 2) for further characterization of the pulmonary abnormalities seen at chest radiography.
Figure 2: Thoracic CT displayed in lung windows (axial A and B, coronal C). Click here for a movie of the axial CT images. Click here for a movie of the coronal CT images.
Regarding the thoracic CT, which of the following statements is most accurate?
