Last modified on 22 June 2006, at 21:41

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