Abstract: Objective　To describe and classify the anatomic variations of pulmonary veins by multi-slice spiral CT (MSCT), so as to provide anatomic basis for radio-frequency ablation of atrial fibrillation and cardio-thoracic surgery.　Methods　Two hundred and fifty patients underwent coronary CT angiography with MSCT were respectively analyzed. The anatomical structure of pulmonary veins was observed by post-processing techniques such as multi-plane reconstruction (MPR), maximum density imaging (MIP) and volume reconstruction (VR). The frequency of each type was classified and counted.　Results　The incidence of common vein and accessory pulmonary veins was 38.8% and 15.2%, respectively, with no gender difference. The left atrium and pulmonary vein connection could be divided into 4 types: 130 cases in standard type (52%), 83 cases in common vein type, which was the most common variation type(33.2%), 23 cases in additional vein type ( 9.2%), and 14 cases in mixed type ( 5.6%). The variation rate of bilateral pulmonary vein drainage patterns was 54%, 26.8% on right side, 42% on left side, with no gender difference.　Conclusions　Pulmonary veins has great variability. MSCT can display pulmonary vein in detail, which is an effective tool to study its anatomical structure.    

Key words: Pulmonary vein, 　Left atrium, 　Multi-slice spiral computed tomography, 　Anatomy