Recipient vessels in free-flap breast reconstruction: a study of the internal mammary and thoracodorsal vessels.

The internal mammary vessels as recipient site for free flaps in breast reconstruction were investigated in this paper because of their ideal location for breast reconstruction. Comparisons were made with the thoracodorsal vessels in terms of external vessel diameter, vessel size discrepancy, flap loss and reexploration rates, and ease of flap placement. Eighty-one patients underwent 110 breast free-flap reconstructions (92 TRAM flaps and 18 superior gluteal flaps) between 1988 and 1994. Vessel size measurements were available on 75 flaps. The internal mammary artery diameter (2.36 +/- 0.50 mm, n = 51) was significantly larger than the thoracodorsal artery diameter (1.79 +/- 0.34 mm, n = 23; p < 0.001). There was no significant difference between the diameters of the internal mammary vein 2.6 +/- 0.58 mm, n = 52) and thoracodorsal vein (2.51 +/- 0.50 mm, n = 23; p = 0.93). The right internal mammary artery (2.52 +/- 0.51 mm) was significantly larger than the left internal mammary artery (2.30 +/- 0.55 mm; p = 0.046). The right internal mammary vein (2.89 +/- 0.56 mm) also was significantly larger than the left internal mammary vein (2.31 +/- 0.48 mm; p = 0.002). In terms of vessel size discrepancy, the internal mammary recipient artery tended to be greater in size than the TRAM flap donor artery (p = 0.003), while the thoracodorsal recipient artery tended to be smaller than the TRAM flap donor artery (p = 0.002). Flap failures and flap reexplorations occurred in the group using the thoracodorsal vessels but not in the internal mammary group. Correct flap placement using the internal mammary recipient site was achieved more easily for both unilateral and bilateral reconstructions because of the avoidance of lateral fullness and medial deficiency problems. The internal mammary recipient site is an important and at times superior alternative to the axillary recipient site because of its larger artery, especially when the axilla is scarred. For smaller free flaps such as a hemi-TRAM flap, as in bilateral TRAM flap reconstructions, the internal mammary site is invaluable because this recipient site allows exact placement of a smaller flap in the breast area.