A 55-year-old woman is scheduled to undergo bipedicled TRAM flap reconstruction of the right breast. Vascular circulation to the umbilicus in this patient will depend primarily on which of the following structures?

(A) Deep inferior epigastric arteries
(B) Lateral umbilical ligament
(C) Ligamentum teres
(D) Subcutaneous fat
(E) Subdermal plexus

The correct response is Option C.

Vascular circulation to the umbilicus in this patient will depend primarily on small vessels of the ligamentum teres. The potential for umbilical necrosis after bilateral TRAM flap reconstruction has significant implications regarding morbidity and recovery from reconstructive surgery. During elevation of a bilateral TRAM flap, the dominant blood supply to the umbilicus is disrupted, and the survival of the umbilical skin becomes dependent on blood flow from lesser sources. Taking care to preserve these sources of blood flow during elevation of the umbilical flap should help to ensure survival of the umbilical skin.

In addition to some contributions from other sources, the umbilicus receives arterial inflow by means of three distinct deep sources: perforating vessels from the deep inferior epigastric arteries, small vessels of the ligamentum teres hepaticum, and the medial umbilical ligament. During unilateral TRAM flap elevation, umbilical blood flow generally remains robust because of a dominance of direct vessels from the contralateral deep epigastric circulation. However, during bilateral TRAM flap elevation, the circulation must depend on the small vessels of the ligamentum teres and medial umbilical ligament because the deep inferior epigastric artery is ligated bilaterally.

The subcutaneous fat contributes little, if any, blood flow to the umbilical skin.

The skin of the umbilicus also receives flow from the subdermal plexus. However, this source of blood to the umbilicus is completely disrupted when the umbilicus is surgically islanded during TRAM flap elevation.

References
1. Itoh Y, Arai K. The deep inferior epigastric artery free skin flap: anatomic study and clinical application. Plast Reconstr Surg. 1993;91:853-856.
2. Stokes RB, Whetzel TP, Sommerhaug E, et al. Arterial vascular anatomy of the umbilicus. Plast Reconstr Surg. 1998;102:761-764.