MR angiography of lower extremities at 3 T: presurgical planning of fibular free flap transfer for facial reconstruction

OBJECTIVE. The purpose of our study was to evaluate the use of preoperative MR angiography of the lower extremities at 3 T in candidates for fibular free flap harvesting, identifying atherosclerotic occlusive disease and congenital anomalies in this population. Our intention was to document the influence of the imaging findings on the surgical approach used. MATERIALS AND METHODS. Twenty-nine consecutive adult patients with facial ab. normalities necessitating mandibular resection with subsequent osteocutaneous mandibular. reconstruction who underwent preoperative MR angiography at 3 T were retrospectively reviewed. Images were evaluated by two observers with regard to image quality and visualization of arterial segments; severity of stenosis; and presence of noise, artifact, or venous contamination. The popliteal artery branching pattern present was also classified. The facial and reconstructive surgeon involved indicated whether the MR angiographic appearances influenced the decision regarding the side or location from which the flap was harvested or the flap design. RESULTS. Arterial segments were visualized with good or excellent image quality in 722 of 725 segments for observer I and 721 segments for observer 2. The kappa coefficient indicated good interobserver agreement (kappa = 0.78) with regard to quality of arterial segment depiction and scoring of stenoocclusive disease (K = 0.64). No segments had venous contamination, noise, or artifact of a degree sufficient to compromise diagnostic interpretation. Imaging influenced the surgical approach in 16 (55.2%) of 29 patients. CONCLUSION. Trifurcation vessel imaging should be a prerequisite to fibular free flap harvesting. High-spatial-resolution MR angiography at 3 T represents a desirable alternative to other invasive or cross-sectional imaging techniques in this regard.