Role of radionuclide imaging in osteoid osteoma.

Radiophosphate bone scans readily disclosed osteoid osteomas in 20 symptomatic patients, including nine patients whose radiographic findings had been negative. In five of the nine patients adjuvant radiogallium imaging was performed, and four showed a disproportionately low uptake relative to radiophosphate. When this occurs, osteoid osteoma can be distinguished from subacute osteomyelitis, which is particularly helpful if the radiograph is equivocal. Radiophosphate bone imaging's generally accepted excellent sensitivity in disclosing obscure symptom-producing focal bone disorders makes it the screening procedure of choice, especially if osteoid osteoma is considered in the differential diagnosis. Only abnormal areas need to be radiographed to add specificity and more precise delineation.