The Society of Thoracic Radiology has recently revised its curriculum establishing “Signs in Thoracic Radiology” as one of its “knowledge-based objectives.” We aim to provide a pictorial and informational review of these 19 classic signs so that the radiologist can define, identify and state the significance of these signs.

The cases will be presented in quiz format. Key differential diagnostic points will be highlighted in the discussion of each case. The cases include: ● air bronchogram ● air crescent sign ● deep sulcus sign ● continuous diaphragm sign ● ring around the artery sign ● fallen lung sign ● flat waist sign ● gloved finger sign ● Golden S sign ● luftsichel sign ● Hampton’s hump ● silhouette sign ● cervicothoracic sign ● tapered margins sign ● figure 3 sign ● fat pad sign

In further support of the ACGME “core competencies,” the Society of Thoracic Radiology has made these classic signs part of their “knowledge based objectives” for radiology residents. After completion of this quiz, the reader will be able to effectively identify 19 classic signs in chest radiology, describe the findings, and state the significance of each sign.