Non-specific Orbital Inflammatory Disease

Abstract

The term orbital pseudotumour was first coined in 1905 to describe an idiopathic condition that produced a mass effect and inflammatory features in the orbit, after exclusion of infection and malignancy. It is now increasingly replaced by the terms “orbital inflammatory disease” (OID) or “idiopathic orbital inflammation”, as its wide spectrum of clinical presentation is increasingly recognized. Orbital inflammatory disease can be divided into specific and non-specific orbital inflammations. Specific orbital inflammatory disorders include idiopathic sclerosing inflammation, granulomatous disorders, transitional lesions (e.g. Sjogren’s syndrome, Kimura disease), vasculitic disorders (e.g. granulomatosis with polyangiitis [Wegener’s granulomatosis]), and others. Non-specific inflammatory cases are a diagnosis of exclusion, and can be classified according to their location in the orbit: anterior, diffuse, apical, myositic, and lacrimal.