Imaging of the Major Salivary Glands in Rheumatic Disease

The salivary glands may be affected by a variety of rheumatologic diseases, including SS, IgG4-RD, sarcoidosis, ANCA associated vasculitis, and other connective tissue disease and must be distinguished from infection and malignancy. US and MRI are generally preferred for evaluation of the salivary glands. US is a useful, noninvasive, nonionizing, inexpensive imaging modality that can be performed at the bedside in the evaluation of salivary gland involvement in rheumatic disease. MRI is the modality of choice if malignancy is suspected. Conventional sialography and scintigraphy have fallen out of routine use given radiation exposure, lack of specificity, and the invasiveness of the procedure in conventional sialography; MR sialography is a potential alternative. If systemic disease is suspected in other organs in addition to the salivary glands, PET/CT may assist in evaluation. Salivary gland imaging offers valuable objective data, which, when integrated with clinical context and laboratory assessments, aids in identifying and characterizing disease.