The aim of our educational exhibit is to illustrate the more common imaging findings ofCentral Nervous System (CNS) manifestations in Immunoglobulin G4-related disease (IgG4-RD), with a special focus on perineural spread.

IgG4-related disease (IgG4-RD) is an immune-mediated chronic relapsing–remitting inflammatory condition, characterized by tumefactive lesions made by a dense lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells, storiform fibrosis, and elevated serum IgG4 concentrations(1). IgG4–RD is now recognised as a multisystemic disorder which can affect virtually any organ(2); as in other fibromatous disease (i.e. sarcoidosis), the histopathological features are consistent among different organs. The organs commonly affected by IgG4-RD are pancreas, bile ducts, salivary and lacrimal glands. The central nervous system is less commonly involved, although a...

MRI demonstrates intermediate to hypointense mass-like or infiltrative lesions on T2-weighted sequences. Diffusion-weighted imaging (DWI) usually shows mild apparent diffusion coefficient (ADC) reduction. Contrast enhancement is always present. CT is mandatory to assess concomitant bone involvement of the skull and the facial bones. MRI is superior to CT for the anatomical evaluation of the optic chiasm, nerve roots, brainstem and skull base involvement(8). We reviewed the imaging findings of 17 IgG4-RD patients with CNS involvement who presented to our Institution. MENINGES The meningeal involvementwas present...

CNS imaging assessment by MRI, including sequences for orbital and sellar regions, should be systematically performed when this disease is suspected.This diagnosis should be considered in the setting of T2-hypointense and enhancing lesions of the branches of cranial nerves (mostly trigeminus). Radiologists should be aware of the described imaging findings to rule out differential “mimics”, especially neoplastic conditions (i.e., lymphoma); furthermore, an early diagnosis of IgG4-RD can lead to a prompt and appropriate medical treatment, reducing disability for patients.

A. Napolitano; Milan/IT - nothing to disclose S. Gerevini; Bergamo/IT - nothing to disclose R. Cao; Milan/IT - nothing to disclose

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