Internal mammary veins: classification and surgical use in free-tissue transfer.

The internal mammary artery has been well-investigated due to its frequent use in cardiac surgery. However, in reconstructive microsurgery in the thoracic region, the internal mammary vessels have been used rarely as recipient vessels, due to difficulties and lack of knowledge about the internal mammary veins. This study was designed to investigate the anatomy and topography of the veins. Its goal was to gain sufficient information about their availability in free-tissue transfer. Dissection of the vessels was performed in 86 cadavers bilaterally to the sternum. At the level of the fourth rib, which is the most desired access for microvascular anastomosis in reconstructive breast surgery with free flaps, the veins were found to be adequately large (range 0.64 to 4.45 mm). Results were in close agreement with 100 bilateral measurements obtained by color Doppler sonography in 16 patients preoperatively, and additionally in 34 healthy volunteers. Preoperative detection of vessels with the aid of sonography facilitated planning of surgical procedures. According to these findings, the internal mammary veins may be used as suitable recipient veins for free microvascular tissue transfer, especially for established autologous breast reconstruction with the free transverse rectus abdominis myocutaneous flap, or for reconstruction of complex thoracic-wall defects.