By Dr Deepu
The Luftsichel sign is seen in some cases of left upper lobe collapse and refers to the frontal chest radiographic appearance due to hyperinflation of the superior segment of the left lower lobe interposing itself between the mediastinum and the collapsed left upper lobe.
Radiographic features
Chest radiograph
In many cases of left upper lobe collapse the anterior parts of the aortic arch, and thus the aortic knuckle, are abutted by collapsed lung and thus the normal silhouette is lost. In some case the apical (superior) segment of the left lower lobe is hyperinflated and becomes interposed between the collapsed lung and the adjacent aortic arch. In such cases the aortic knuckle silhouette remains visible. The collapsed left upper lobe is thus displaced laterally away from the mediastinum.
Luftsichel sign ( A german word ; Luft = Air and Sichel = Sickle ) . The luftsichel sign represents the hyperexpanded superior segment of the left lower lobe interposed between the atelectatic left upper lobe and the aortic arch.
Reference:
Webb WR, Higgins CB. Thoracic Imaging: Pulmonary and Cardiovascular Radiology. Lippincott, Williams & Wilkins 2005
http://radiopaedia.org/articles/luftsichel-sign
http://www.radpod.org/2007/06/08/left-upper-lobe-collapse/
http://www.lungindia.com/article.asp?issn=0970-2113;year=2012;volume=29;issue=1;spage=83;epage=84;aulast=Singh
http://www.radrounds.com/photo/luftsichel-sign
The Luftsichel sign is seen in some cases of left upper lobe collapse and refers to the frontal chest radiographic appearance due to hyperinflation of the superior segment of the left lower lobe interposing itself between the mediastinum and the collapsed left upper lobe.
Radiographic features
Chest radiograph
In many cases of left upper lobe collapse the anterior parts of the aortic arch, and thus the aortic knuckle, are abutted by collapsed lung and thus the normal silhouette is lost. In some case the apical (superior) segment of the left lower lobe is hyperinflated and becomes interposed between the collapsed lung and the adjacent aortic arch. In such cases the aortic knuckle silhouette remains visible. The collapsed left upper lobe is thus displaced laterally away from the mediastinum.
Luftsichel sign ( A german word ; Luft = Air and Sichel = Sickle ) . The luftsichel sign represents the hyperexpanded superior segment of the left lower lobe interposed between the atelectatic left upper lobe and the aortic arch.
Reference:
Webb WR, Higgins CB. Thoracic Imaging: Pulmonary and Cardiovascular Radiology. Lippincott, Williams & Wilkins 2005
http://radiopaedia.org/articles/luftsichel-sign
http://www.radpod.org/2007/06/08/left-upper-lobe-collapse/
http://www.lungindia.com/article.asp?issn=0970-2113;year=2012;volume=29;issue=1;spage=83;epage=84;aulast=Singh
http://www.radrounds.com/photo/luftsichel-sign