INDIUM 111-LABELED LEUKOCYTE SCINTIGRAPHY IN EVALUATING HEAD AND NECK INFECTIONS

This retrospective study looked at the role of indium 111-labeled white blood cell (In-111 WBC) scintigraphy in head and neck infections. The efficacy of In-111 WBCs was compared to gallium 67 citrate (Ga-67( and technetium Tc-99m methylene diphosphonate (Tc-99m MDP) scintigraphy in detecting and monitoring the resolution of infection. For 22 active infections, the sensitivities for In-111 WBC, Ga-67, and Tc-99m MDP scintigraphy were 94%, 56%, and 86%, respectively, and the specificities for In-111 WBC, Ga-67, and Tc-99m MDP scintigraphy were 100%, 43%, and 0%, respectively. For 8 successfully treated infections, all seven In-111 WBC studies became negative after therapy, in as short an interval as 1 month. In contrast, all seven Tc-99m MDP images remained positive for as long as 6 months after therapy. The seven Ga-67 studies had variable results, with four (57%) remaining positive, including two (28%) positive at 6 months after therapy. These results suggest that In-111 WBC scintigraphy should be the initial radionuclide imaging tool in detecting active head and neck infections because of its greater accuracy, and its ability to revert to normal much sooner than Ga-67 or Tc-99m MDP scintigraphs when applied to a subset of patients with resolved infections.