[Retrograde flow in the left internal jugular vein caused by compression of the left brachiocephalic vein while supine during moderate tidal volume ventilation: case report, evaluation by colour coded duplex sonography and review of literature].

This report describes a 67-year-old healthy woman with retrograde flow in the left jugular vein in the supine position during moderate tidal ventilation detected by colour coded duplexsonography. In the upright position, an alternating flow could be found with antegrade direction during inspiration and retrograde flow during expiration. CT scan showed no abnormality in the mediastinum. CT-angiography in full inspiration demonstrated a normal contrast-enhanced left brachiocephalic vein. This finding suggests respiration-dependent compression of the left brachiocephalic vein between the aortic arch and the sternum in the supine position. The clinical relevance for patients with morning headaches is discussed. In cases of this phenomenon it is not advisable to use veins of the left arm for contrast media injection in CT- or MR-angiography.