The internal thoracic vein for the breast and thoracic surgical reconstruction: anatomy of the valves.

The internal mammary veins (IMV) are suitable vessels for thoracic wall recon- struction thanks to their relatively predictable anatomy and because they are less a ected by atherosclerosis, injury or scarring of previous surgery and radiotherapy. Their position near to the lateral border of the sternum allows easier access for sur- geon and the possibility of placing the most vascularized part of a ap for breast reconstruction in the medial thoracic region [1]. As the complexity of reconstruction has increased, the use of the caudal portion of IMV has been reported as a conveni- ent option for additional venous drainage. This procedure, requires retrograde blood ow that could be altered by the presence of e cient valves in the IMV. In this study, we evaluated 32 IMVs dissected from 16 fresh cadaver thoracic walls. Retrograde blood ow and the presence of valves were investigated. We observed an e cient ow in 18 IMVs, partial ow in 7 IMVs and no ow in 5 IMVs. In these last, single and/or multiple sacciform swelling and competent valves were macroscopically observed. Histomorphological analysis by Haematoxylin and Eosin and Masson-Goldner Trichrome staining con rmed their presence. In addition, some rudimental valves, not identi ed macroscopically, were found during histomor- phological analysis. Taking together, these data highlight the possible presence of complete or rudi- mental valves in IMV. This aspect should be considered when retrograde ow of IMV as a single venous drainage was performed during surgical breast and thoracic recon- struction.