CLINICAL EFFECTIVENESS OF TC-99M-DIPHOSPHONATE SCINTIGRAPHY OF REVASCULARIZED ILIAC CREST FLAPS

Clinical assessment of the perfusion of the musculocutaneous portion o f composite iliac crest free flaps was compared to Tc-99m-diphosphonat e (HDP) uptake in 14 patients who underwent primary oromandibular reco nstruction after ablative cancer surgery. Bone scanning was performed on average at the 9-10th postoperative day (range 4-48) 3 h after intr avenous injection of 550 MBq Tc-99m-HDP. Eleven patients showed comple te concordance between Tc-99m-HDP uptake and soft-tissue status. Two p atients showed uptake and viable muscle in spite of necrotic skin. One patient had a viable musculocutaneous flap but a photopenic defect in the bone graft; 6 months later, a small corresponding part of the bon e was sequestrated. In this study, bone scanning and clinical assessme nt of muscle perfusion were 100% accurate in predicting viability of b one grafts. Skin viability was a less reliable parameter. It is conclu ded that bone scanning is not indicated as a routine investigation for revascularized iliac crest flaps and that clinical assessment of musc le perfusion is a reliable monitor of the early function of such flaps .