Radiological signs on orbital imaging of immunoglobulin G4-related disease

Immunoglobulin G4 (IgG4)-related disease has strong organ predilections, and orbital involvement is not rare. Eyelid puffiness with erythema, extraocular movement deficit with proptosis are common presentations, which could sometimes mimic thyroid-associated orbitopathy. With a better understanding on orbital radiology, these “hot eyes” could be managed better.