Orbital inflammatory disease: Pictorial review and differential diagnosis

Orbital inflammatory disease (OID) represents a collection of inflammatory conditions affecting the orbit. OID is a diagnosis of exclusion, with the differential diagnosis including infection, systemic inflammatory conditions, and neoplasms, among other conditions. Inflammatory conditions in OID include dacryoadenitis, myositis, cellulitis, optic perineuritis, periscleritis, orbital apicitis, and a focal mass. Sclerosing orbital inflammation is a rare condition with a chronic, indolent course involving dense fibrosis and lymphocytic infiltrate. Previously thought to be along the spectrum of OID, it is now considered a distinct pathologic entity. Imaging plays an important role in elucidating any underlying etiology behind orbital inflammation and is critical for ruling out other conditions prior to a definitive diagnosis of OID. In this review, we will explore the common sites of involvement by OID and discuss differential diagnosis by site and key imaging findings for each condition.

Optic perineuritis as a rare initial presentation of sarcoidosis

Sarcoidosis is a multisystem granulomatous disorder of unknown aetiology and establishing the correct diagnosis can be challenging. Although dysfunction of the anterior visual pathways is uncommon, it is the most common neuro-ophthalmological manifestation of this condition and given the potential for irreversible, severe visual loss, prompt diagnosis and treatment are essential. We describe a patient with optic perineuritis as a rare initial presentation of sarcoidosis and discuss the underlying pathophysiology and management.