Diagnostic Radiology/Chest Imaging/Chest Signs

Be able to define, identify and state the significance of the following on a radiograph: air bronchogram - indicates a parenchymal process, including non-obstructive atelectasis, as distinguished from pleural or mediastinal processes air crescent sign - indicates a lung cavity, often due to fungal infection deep sulcus sign on a supine radiograph - indicates pneumothorax continuous diaphragm sign - indicates pneumomediastinum ring around the artery sign (around pulmonary artery on lateral chest radiograph) - indicates pneumomediastinum fallen lung sign - indicates a fractured bronchus flat waist sign- indicates left lower lobe collapse gloved finger sign - indicates bronchial impaction, which can be seen in allergic bronchopulmonary aspergillosis Golden S sign - indicates lobar collapse with a central mass, suggesting an obstructing bronchogenic carcinoma in an adult luftsichel sign - indicates upper lobe collapse, potentially due to an obstructing bronchogenic carcinoma in an adult Hampton's hump - indicates a pulmonary infarct silhouette sign - loss of the contour of the heart or diaphragm used to localize a parenchymal process (e.g. a process involving the medial segment of the right middle lobe obscures the right heart border; a lingula process obscures the left heart border; a basilar segmental lower lobe process obscures the diaphragm) cervicothoracic sign - a mediastinal opacity that projects above the clavicles is retrotracheal and posteriorly situated while an opacity effaced along its superior aspect and projecting at or below the clavicles is situated anteriorly tapered margins sign - a lesion in the chest wall, mediastinum or pleura will have smooth tapered borders and obtuse angles with the chest wall or mediastinum while parenchymal lesions usually form acute angles figure 3 sign - abnormal contour of the descending aorta, indicating coarctation of the aorta fat pad sign or sandwich sign - indicates pericardial effusion on lateral chest radiograph scimitar sign - an abnormal pulmonary vein in venolobar syndrome double density sign - contour projecting over the right side of the heart, indicating enlargement of the left atrium hilum overlay sign and hilum convergence sign -used to distinguish a hilar mass from a non-hilar mass Be able to define, identify and state the significance of the following on a chest CT: CT angiogram sign - enhancing pulmonary vessels against a background of low attenuation material in the lung halo sign - suggesting invasive pulmonary aspergillosis in a leukemic patient split pleura sign - a sign of empyema