Silhouette sign
| Silhouette sign | |
|---|---|
 | |
| A) Normal chest radiograph; B) Q fever pneumonia affecting the right lower and middle lobes. Note the loss of the normal radiographic silhouette (contour) between the affected lung and its right heart border as well as between the affected lung and its right diaphragm border. This phenomenon is called the silhouette sign | |
| Differential diagnosis | right middle lobe syndrome |
In
right lower lobe pneumonia, where the border of the diaphragm on the right side is obscured, while the right heart margin remains distinct.[2]
Silhouette sign is very useful in localizing lung lesions as all structures forming cardiac silhouette are in contact with a specific portion of the lung.
References
- ^ Silouette Sign, 2008, Family Practice Notebook, LLC. Retrieved 9 February 2010.
- ^ a b The silhouette sign and possible mechanisms, Ian Maddison Nov 1994, revised Nov. 2007. Retrieved 9 February 2010.
- ISBN 978-0-443-07008-2.
Further reading
- The Silhouette Sign Revisited, Vernon J. Louw, Adrian Schmidt, Chris T. Bolliger. Lung Unit, Department of Internal Medicine, Tygerberg Hospital, Cape Town, South Africa.