Tc-99m methoxyisobutylisonitrile parathyroid scintigraphy: the value of adding a whole-body scan.

PURPOSE: The aim of this study was to estimate the frequency of incidental findings on Tc-99m-methoxyisobutylisonitrile (MIBI) scan performed for suspected parathyroid adenoma and to evaluate the benefit of additional whole-body scan. MATERIALS AND METHODS: A total of 109 patients (37 men and 72 women; age range, 16-96 years; mean, 58.42 years) with clinically suspected parathyroid adenoma underwent Tc-99m MIBI whole-body scans and single-photon emission computed tomography of the base of the skull, the neck, and the thorax. Each case with suspected abnormal tracer accumulation was analyzed and correlated with clinical information. RESULTS: MIBI single-photon emission computed tomography of the base of the skull, the neck, and the thorax and whole-body scans of 109 patients were assessed. A total of five incidental findings were detected. The anatomical distribution of the incidental findings was as follows: two (40%) were located in the head and neck areas and three (60%) were in the abdomen and pelvis. Two (40%) were detected in standard acquisition view, which includes the base of the skull, the neck, and the thorax. Three (60%) incidentalomas were detected in whole-body scan. In addition, we found 23 cases of abnormal tracer distribution that were correlated with known clinical history of patients. Three (13%) were located in the head and neck areas, 10 (43.6%) in the thoracic region, six (26%) in the abdomen and pelvis, and four (17.4%) in the extremities. CONCLUSION: Whole-body imaging in patients with suspected parathyroid adenoma who underwent MIBI scans does not alter patient management in most cases.