Anatomy of the vascular pedicle of the internal mammary artery perforator (IMAP) flap as applied for head and neck reconstruction.

Introduction: The vascular pedicle of the internal mammary artery perforator (IMAP) flap and its enhancement by inclusion of the internal mammary vessels up to the level of the first rib have not been systematically assessed anatomically, to date. This study assesses these features of this pedicle in light of the flap's application in head and neck reconstruction.

Material And Methods: The length of the dominant perforator and the enhanced vascular pedicle of the IMAP flap were measured in 27 fresh cadaveric hemi-thoraxes.

Results: In 18 out of 27 cadaveric cases (0.67) the second perforator was dominant. The mean length of the 27 dominant perforators was 47 mm (range: 30-66 mm). By enhancement up to the level of the first rib, the mean length of the vascular pedicle could be doubled to 92 mm when based on the second perforator (0.67). In the five cases (0.19), where the third perforator was dominant, the mean length of the enhanced pedicle was 104 mm, whereas it was 61 mm in the four cases (0.15) where the first perforator was dominant.

Conclusion: This is the first study that assessed the enhanced length of the vascular pedicle of the IMAP flap. Our results show that the mean length of the dominant second perforator may be doubled by such enhancement and that the arc of rotation to the head and neck region may, then, be doubled again. Hereby, even high-located defects in the head and neck region can be reached. This provides a better understanding of the feasibility of the pedicled IMAP flap in head and neck reconstruction.