Figure 1. Pulmonary vein (PV) anatomy assessment with multislice CT (MSCT). Three-dimensional volume-rendered reconstructions of MSCT scans show a dorsal view on the PVs. (A) Normal PV anatomy is shown. Four PVs are present, each with a separate ostium: left inferior pulmonary vein [LIPV], left superior pulmonary vein [LSPV], right inferior pulmonary vein [RIPV], and right superior pulmonary vein [RSPV]. (LA = left atrium.) (B and C) Variations in PV anatomy. (B) An additional right-sided PV is shown (arrow). (C) This image shows an example of a common ostium of the left-sided PVs (double-headed arrow).