Читать книгу Respiratory Medicine - Stephen J. Bourke - Страница 120

1 4.1 DCavitation is the presence of an area of radiolucency within a mass lesion. It is a feature of squamous carcinoma, tuberculosis, lung abscess, pulmonary infarcts, granulomatosis with polyangiitis (formerly known as Wegener granulomatosis) and some pneumonias (e.g. Staphylococcus aureus, Klebsiella pneumoniae).

2 4.2 DAn air bronchogram is visible as a black tube of air against the white background of consolidated lung. It indicates that the bronchus is patent and not occluded. It is a feature of pneumonic consolidation.

3 4.3 BAvid uptake of FDG on PET scanning is a feature of bronchial carcinoma, but can also occur in inflammatory conditions such as tuberculosis, sarcoidosis, histoplasmosis and coccidioidomycosis. Small lesions (<1 cm) may be falsely negative but if a small lesion is ‘hot’ then it suggests significant metabolic activity. Neurofibromas would be expected to be ‘cold’ on PET.

4 4.4 DCollapse of a lobe is a sinister feature suggesting occlusion of the bronchus by a mass lesion such as a carcinoma.

5 4.5 ESee Fig. 4.8.

6 4.6 DAbsence of the normal ‘silhouette’ between the right diaphragm and the adjacent lung (lower lobe) implies there is consolidation in the lung.

7 4.7 C and D are possible and need to be considered Congenital problems leading to poor development of the lung tend to leave a radiolucent X‐ray on that side. Pulmonary embolism may leave no sign or a subtle diminution of vascular markings. ‘Complete’ consolidation of an entire lung – with no involvement of the other lung – is an extremely unlikely finding.

8 4.8 CIn a large effusion, the trachea (and mediastinum) will be pushed ‘away’ to the other side. In collapse, the trachea (and mediastinum) will be pulled to that side.

9 4.9 DInjection of radiocontrast material into a peripheral vein yields the CT pulmonary angiogram (CTPA) which can be used to identify emboli in central pulmonary arteries in thromboembolic disease.

10 4.10 EIf the level is ABOVE the arch of the aorta then the aorta will not be visible. Also see Fig. 4.10.