Scimitar syndrome versus meandering pulmonary vein: evaluation with three-dimensional computed tomography.

We report two cases of abnormal configuration of the pulmonary venous system of the right lung evaluated with the use of three-dimensional spiral computed tomography (3D-CT). In the first case, an unusual form of scimitar syndrome was detected, consisting of two scimitar veins uniting into a common trunk immediately before their confluence into the inferior vena cava (IVC). The second case concerns a meandering pulmonary vein that followed a circuitous course through the right lung and came in close proximity to the IVC, before draining the entire right lung to the left atrium. In both cases, 3D-CT enabled a non-invasive, detailed anatomic evaluation of the right pulmonary vascular bed.