Analysis of the variation pattern in right upper pulmonary veins and establishment of simplified vein models for anatomical segmentectomy

Thoracic surgeons must be erudite pulmonary vein variation when performing anatomical segmentectomy. We used three-dimensional CT (3DCT) to accumulate variations of the pulmonary veins of the right upper lobe (RUL) and created a simplified RUL vein model. We reviewed anatomical variations of the RUL pulmonary veins of 338 patients using 3DCT images, and classified them by position related with bronchus. Of the "anterior" and "central" RUL veins, all could be classified into 4 types: 2 Anterior with Central types (Iab and Ib), 1 Anterior type, and 1 Central type. The Anterior with Central type was observed in 273 patients (81 %), and was further classified into two types according to the origin of the anterior vein. In the Iab type, the anterior vein originated from V1a to V1b (54 %) whereas, in the Ib type, the anterior vein originated from only V1b (26 %). The Central type, which had no anterior vein, was evident in 23 cases (7 %). These three types could be further divided into three subcategories by reference to the branching pattern of the central vein. The Anterior type, which had no central vein, was evident in 42 cases (12 %), and this type could be further categorized into two types, depending on the branching pattern of the anterior vein. We created a simplified RUL vein model to facilitate anatomical segmentectomy. Our models should find wide application, especially when thoracic surgery requiring anatomical RUL segmentectomy is planned.