A REPRODUCIBILITY STUDY OF TC-99M MACROAGGREGATED ALBUMIN FOOT PERFUSION IMAGING IN PATIENTS WITH DIABETES-MELLITUS

The reproducibility of Technetium-99m macroaggregated albumin (Tc-99m- MAA) foot perfusion imaging was assessed in 14 diabetic patients with foot ulcers. Bilateral femoral intra-arterial injections of Tc-99m-MAA were administered and the feet imaged with a gamma camera. Patients r eturned 1 week later for a repeat study. The scans of 10 patients incl uding one unilateral amputee were evaluated. Of these 19 limbs there w ere 4 failed injections (21 %). The remaining 15 completed repeat stud ies were analysed both subjectively and semiquantitatively by 2 differ ent observers who were blind to the patient's name and scan date. Subj ectively the images of each individual were similar with reports highl ighting the same abnormalities. Semiquantitatively areas of increased uptake on both images were significantly correlated for each individua l (Pearson's Rho correlation coefficient = 0.96, r(2) = 0.92, p<0.0001 ) as were areas of poor uptake reported, reflecting decreased tissue p erfusion (Pearson's Rho = 0.93, r(2) = 0.86, p<0.0001). There were no side-effects. Tc-99m-MAA has proven to be a safe, generally acceptable , and reproducible technique for assessing tissue perfusion in the ext remities which provides an accurate means of differentiating viable fr om non-viable tissue in patients with foot ulcers.