SPECT gallium scintigraphy in malignant external otitis: initial staging and follow-up. Case reports.

Malignant external otitis (MEO) is a recognized entity characterized by a stubborn Pseudomonas external otitis; it has been most frequently observed in elderly diabetic patients. Early diagnosis is necessary for successful treatment but, despite a widespread inflammatory response, routine plain x-ray studies and computed tomography (CT) scanning show no abnormalities in its early stage. In this report, the clinical value of gallium 67 (Ga 67) single photon emission CT (SPECT) is studied in three patients suspected of having MEO, and the results are compared with findings on CT scan and laboratory tests. These results confirm that the high sensitivity of GA 67 SPECT in the initial recognition of MEO provides a more adequate technique than CT scan. Furthermore, Ga 67 scintigraphy appears to be highly accurate for follow-up evaluation of these patients.