Figure 10b. Supernumerary (accessory) pulmonary veins. VR images (epicardial view) from gated (a, c) and nongated (b) multi-detector row CT performed in three different patients show an accessory right middle lobe pulmonary vein (RM in a), a superior segment right lower lobe (ssRLL) pulmonary vein (b), and a lingula pulmonary vein (c). Accessory veins contribute to the complexity of normal pulmonary venous anatomy and may drain a pulmonary lobe or lobe segment.