Aneurysm of the internal jugular vein manifesting after prolonged positive pressure ventilation.

True internal jugular vein aneurysms are exceedingly rare anomalies. To date very few case reports have appeared regarding this entity. We present a case of a congenital internal jugular venous aneurysm which manifested itself after abdominal surgery and prolonged positive pressure ventilation. A theory regarding its manifestation is presented. We believe this case to be unique in its presentation.