Chest imaging sings

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

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

LINKS:

http://www.faardit.org.ar/conf/035_CHP/SIGNS_IN_THORACIC_IMAGING.pdf