Tc-99m methoxyisobutylisonitrile parathyroid scintigraphy

Abstract

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. 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. 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. Whole-body imaging in patients with suspected parathyroid adenoma who underwent MIBI scans does not alter patient management in most cases.