Modern Perforator Flap Imaging with High-Resolution Blood Pool MR Angiography

Advances in microsurgical techniques have improved autologous reconstructions by providing new donor site options while decreasing donor site morbidity. Various preoperative imaging modalities have been studied to assess the relevant vascular anatomic structures, with magnetic resonance (MR) angiography traditionally lagging behind computed tomography (CT) with respect to spatial resolution. Blood pool MR angiography with gadofosveset trisodium, a gadolinium-based contrast agent with extended intravascular retention, has allowed longer multiplanar acquisitions with resultant voxel sizes similar to or smaller than those of CT and with improved signal-to-noise ratio and soft-tissue contrast while maintaining the ability to depict flow with time-resolved imaging. The resultant vascular detail enables precise evaluation of the relevant vascular anatomic structures, including the vessel course, size, and branching pattern, as well as the venous arborization pattern. In addition, any architectural distortion, vessel alteration, or injury from prior surgery can be depicted. The reporting radiologist should be aware of pertinent and incidental findings relevant to the planned surgery and the patient's disease so that he or she can assist the microsurgeon in flap design as a member of the multidisciplinary team. Given the lack of ionizing radiation exposure in patients who often have an elevated body mass index, high-spatial-resolution blood pool MR angiography has become the imaging reference standard for the preoperative assessment of perforator flap vascular and soft-tissue morphology in our practice.