Diagnostic dilemmas in orbital inflammatory disease

Orbital inflammatory disease (OID) broadly describes a variety of pathologic processes and clinical presentations. OID may be idiopathic or may be secondary to a systemic inflammatory disease, retained foreign body, or infectious disease. OID includes the spectrum of bacterial or fungal infections, diffuse inflammation of multiple tissues (e.g., sclerosing orbititis or diffuse anterior OID), and preferential involvement of specific orbital structures (e.g., orbital myositis or optic perineuritis). Mimics of OID include congenital orbital mass lesions or orbital neoplastic disease such as lymphoma or rhabdomyosarcoma. The ultimate diagnosis and treatment plan relies on a careful history and detailed clinical examination followed by the judicious use of ancillary diagnostic testing and a comprehensive treatment plan. The purpose of this review is to provide an overview of the spectrum of diseases known as OID, with emphasis on specific diagnostic challenges in the evaluation and management of patients with idiopathic OID.