[The scimitar sign: a pulmonary vein or systemic artery? Apropos of a case of pure vascular sequestration].

The scimitar sign, characterised by a vertical opacity crossing the medial part of the right diaphragm, is generally attributed to abnormal pulmonary venous return draining into the inferior vena cava. This is not the only situation in which the scimitar sign is observed, which can also be seen in association with systemic anomalies, in particular sequestration. The authors report the case of a young adult in whom the chest x-ray presented the scimitar sign from childhood. This image was related to a pure pulmonary vessel sequestration by a right sub-phrenic artery. The authors stress the possibility of a purely arterial origin for the scimitar sign in the absence of any abnormality of pulmonary venous return.