OBJECTIVETo investigate the distribution of the internal mammary artery and its branches by the multi-slice spiral CT angiography, and to explore the feasibility of transferring pedicled transverse rectus abdomials myocataneous (TRAM) flap for breast reconstruction through resection of inferior costicartilages.

METHODS30 female patients received abdominal CT angiography. (1) The distance between internal mammary artery and the sternum midline were recorded; (2) The position and the numbers of branches from bilateral internal mammary arteries at the level of 5th, 6th, 7th rib was observed; (3) The points where the superior epigastric artery gets through the rectus abdominis muscle were located.

RESULTS( The average distance between left internal mammary artery to the sternum midline is from 1. 66 cm (0. 62-2. 39 cm ) to 2.34 cm (0.69-3.36 cm) at the level from 4th to 6th intercostal space. The average distance between right internal mammary artery to the sternum midline is from 1.55 cm(0. 66-2. 29 cm) to 2.29 cm(0. 73-3. 67 cm) at the level from 4th to 6th intercostal space; ) The number of branches is the most at the level of 6th intercostal space; (3) There are 235 branches in the superior epigastric artery.

CONCLUSIONSThis imaging study of internal mammary artery explores the feasibility of transferring pedicled transverse rectus abdominals myocataneous flap for breast reconstruction. It has important significance in the breast reconstruction using TRAM flap with lengthened pedicle.