IgG4-related Disease of the Head and Neck: CT and MR Imaging Manifestations

Abstract

Immunoglobulin G4 (IgG4)-related disease is a recently established systemic disease that commonly involves the head and neck, including the salivary glands, lacrimal glands, orbits, thyroid gland, lymph nodes, sinonasal cavities, pituitary gland, and larynx. Although the definitive diagnosis of IgG4-related disease requires histopathologic analysis, elevated serum IgG4 levels are helpful in making the diagnosis. Because of the proposed clinical diagnostic criteria for this disease, cross-sectional imaging modalities such as computed tomography (CT) and magnetic resonance (MR) imaging play an important diagnostic role. CT and MR imaging findings of IgG4-related disease are usually nonspecific. At CT, involved organs may demonstrate enlargement or decreased attenuation; at T2-weighted MR imaging, they may have relatively low signal intensity owing to their increased cellularity and amount of fibrosis. Some pathologic entities involving the head and neck are now considered to be part of the IgG4-related disease spectrum, including idiopathic orbital inflammatory syndrome (inflammatory pseudotumor), orbital lymphoid hyperplasia, Mikulicz disease, Küttner tumor, Hashimoto thyroiditis, Riedel thyroiditis, and pituitary hypophysitis. Because involvement of multiple sites is common in IgG4-related disease, radiologists should be familiar with manifestations of this systemic process outside the head and neck, in organs such as the pancreas, bile ducts, gallbladder, kidneys, retroperitoneum, mesentery, lungs, gastrointestinal tract, and blood vessels. Moreover, IgG4-related disease usually demonstrates a dramatic response to corticosteroid therapy, and radiologists should be familiar with its clinical and imaging manifestations to avoid a delay in diagnosis or unnecessary invasive interventions.

Extrasinonasal infiltrative process associated with a sinonasal fungus ball: does it mean invasive fungal sinusitis?

“…Inflammatory pseudotumor is a very diverse group of conditions, characterized by acute and chronic inflammatory cells with a variable fibrous response (26,27). On imaging, the disease may manifest as a mass or infiltrating soft tissue lesion involving the orbit, sinonasal cavity, or skull base, with or without bony destruction (23,(26)(27)(28). CT and MRI show various density and signal intensity with frequent hypointensity on T2-weighted images due to the relative lack of mobile protons within fibrotic lesions (27).…”

Imaging and pathological features of gastric lesion of immunoglobulin G4-related disease: A case report and review of the recent literature

“…Diagnosis of IgG4-RD requires a multidisciplinary approach including various clinical, radiological, and pathological examinations. Radiological findings of major manifestations in various organs, including pancreas, lung, kidney, and aorta/artery, have been published, and radiological examinations and determination of serum IgG4 concentrations are the key steps to achieving the correct diagnosis of IgG4-RD [2,7,[13][14][15][16][17][18]. Although IgG4-RD mainly involves glandular tissues or the vascular system, several case reports have shown that IgG4-RD also involves the gastrointestinal tract with ulcer, polypoid lesions, submucosal mass, and wall thickening.…”

Chronic Sclerosing Sialadenitis of the Submandibular Gland as the Initial Symptom of IgG4-Related Disease: A Case Report

“…In the head and neck region, Mikulicz's disease (affecting the salivary and lacrimal glands), Küttner's tumor (affecting mainly the submandibular glands), Riedel's thyroiditis, Hashimoto's thyroiditis, idiopathic orbital inflammatory syndrome, and pituitary hypophysitis may all be attributable to IgG4-RD (Fujita et al 2012;Stone et al 2012). When such conditions are apparent, it is important to investigate the entire body (not just the head and neck).…”

“…When such conditions are apparent, it is important to investigate the entire body (not just the head and neck). The salivary glands are the organs most frequently involved in IgG4-RD of the head and neck (Fujita et al 2012).…”

“…Affected parts of the body may include the pancreas, biliary duct, central nervous system, lungs, liver, digestive tract, kidneys, prostate, retroperitoneum, aorta, pericardium, lymph nodes, skin, and mammary glands Stone et al 2012). The head and neck can also be affected in IgG4-RD, commonly involving the salivary glands, lacrimal glands, orbits, thyroid gland, lymph nodes, sinonasal cavities, and pituitary stalk, as well as (though less commonly) the larynx, tongue, and palate (Fujita et al 2012;Khurram et al 2013;Andrew et al 2014). Lesions tend to develop in multiple organs simultaneously or metachronously, but are sometimes confined to a single organ.…”