ABSTRACT
<p><b>OBJECTIVE</b>To explore the value of [18F]fluoro-2-deoxy-D-glucose(18 FDG) positron emission tomography and computer tomography (PET/CT) in the qualitative diagnosis and localization of Cushing's disease.</p><p><b>METHODS</b>Totally 12 patients underwent transsphenoidal adenomectomy and were histopathologically proven to be with Cushing's disease. 18FDG PET/CT whole-body and brain scannings were performed preoperatively; meanwhile, magnetic resonance imaging (MRI) and 99mTc-octreotide examination were done in all 12 cases, and inferior petrosal sinus sampling (IPSS) were done in 6 patients.</p><p><b>RESULTS</b>The sensitivity of 18FDG in diagnosing Cushing's disease was 91.6% (11/12), but MRI was 66.7%(8/12). For the 6 patients who performed IPSS, 5 of them was diagnosed to be with Cushing's disease, and only 50% (3/6) were localized correctly in the pituitary gland.</p><p><b>CONCLUSIONS</b>18FDG PET/CT whole-body scan can exclude ectopic adrenocorticotropin-secreting tumors and localize the pituitary lesions with higher accuracy than MRI. Therefore, it is useful for suspected Cushing's disease, especially for patients their MRI and IPSS have negative or paradoxical results.</p>