Contrast-Enhanced Magnetic Resonance Angiography for Preoperative Imaging in DIEP Flap Breast Reconstruction

The blood supply to the lower abdominal tissue is highly variable. The safety of harvest of free abdominal flaps is dependent on the inclusion of suitable perforators for arterial perfusion, and more importantly adequate venous drainage. Presurgical imaging with contrast-enhanced magnetic resonance angiography (CE-MRA) or computed tomographic angiography (CTA) allows evaluation of the characteristics of the individual perforators in three-dimensions in their resting state, including the perforator location, caliber of the arterial perforator and venae commitantes, intramuscular course of the perforator, and branching pattern of the deep inferior epigastric artery (DIEA). The superficial venous system can also be evaluated, as can the presence and caliber of a superficial inferior epigastric artery. Global evaluation of the abdominal wall can also be appreciated, including the presence of rectus divarication and hernias. Presurgical knowledge of these allows planning of the surgery in advance, anticipation of anatomical variations, and better counselling of the patient as to what reconstructive options may be available. More importantly the use of preoperative imaging reduces operative time, decreases flap and donor site complications due to the selection of the best available vessels, facilitates surgical decision-making, and eases surgeon stress. CE-MRA has the particular advantage over CTA of avoidance of ionizing radiation and iodinated contrast media, as well as better imaging of the venous system. In this chapter we review the use of CE-MRA for preoperative flap imaging in the DIEP flap.