Improved detection and characterization of adrenal disease with PET-CT.

Positron emission tomography (PET)-computed tomography (CT) combines complementary modalities, thereby providing useful structural and functional information for the detection and characterization of a variety of conditions affecting the adrenal gland. The coregistered information provided by PET-CT is often superior to that provided by CT or PET owing to a variety of pitfalls inherent in the use of either modality alone. In addition, PET-CT can prove invaluable in the differentiation between benign and malignant adrenal disease. However, this combined modality also has certain limitations. Benign entities such as lipid-poor adenomas may demonstrate increased uptake at 2-[fluorine 18]fluoro-2-deoxy-d-glucose PET while being indeterminate at standard CT. Moreover, the combined information from PET-CT will not always obviate additional studies or biopsy. Nevertheless, radiologists and nuclear physicians should be familiar with the common as well as the atypical manifestations of adrenal disease at PET and CT. They should also be meticulous in the performance and interpretation of PET-CT, which is crucial for optimal diagnosis and treatment. (c) RSNA, 2007.