An anatomic study of the internal mammary veins: Clinical implications for free-tissue-transfer breast reconstruction

The anatomy of the internal mammary vessels is poorly understood and thought to be unreliable clinically for use as a recipient vein in free- tissue-transfer breast reconstruction. This study of 10 fresh cadaver thoracic cavities demonstrated by anatomic and dye resection studies that the internal mammary veins become smaller (≤2 mm) distally (fourth rib) and bifurcate [left (90 percent) > right (40 percent)], becoming unsuitable for consistent venous anastomoses at or below the fourth interspace. Furthermore, this study suggests that the most consistent interval is the third rib, which offers an appropriate recipient vein (40 percent ≤ 3 mm on the left and 70 percent ≤ 3 mm on the right). However, at the fourth interspace, 20 percent of the cadaver specimens had a vein on one side that was 1 mm or less and therefore unsuitable as a recipient. This enhanced understanding of the anatomy (size, location, and consistency) of the internal mammary recipient veins offers our patients another recipient option to enhance the safety and technical case of microvascular breast reconstruction.