Orbital IgG4 Disease: Imaging Findings on 68Ga-DOTANOC PET/CT

Immunoglobulin G4 (IgG4)–related diseases are a spectrum of systemic inflammatory conditions of unknown etiology, which are characterized by infiltration of tissues by IgG4 plasma cells and sclerosing inflammation (Cheuk and Chan Adv Anat Pathol 17:303–32, 2010). Although this condition was initially described in relation to autoimmune pancreatitis, now it has been reported in almost every organ system of body (Zen and Nakanuma Am J Surg Pathol...