Homonymous Superior Quadrantanopia due to Erdheim-Chester Disease with Asymptomatic Pituitary Involvement.

Polyostotic sclerosing histiocytosis, also known as Erdheim-Chester disease (ECD), is a rare form of non-Langerhans histiocytosis. ECD has wide clinical spectrums which mainly affect skeletal, neurological, dermatological, retroperitoneal, cardiac, and pulmonary manifestations. Here we describe a case of ECD in a 45-year-old female who presented initially with bilateral knee pain and homonymous superior quadrantanopia progressed to ophthalmoplegia and complete visual loss of the left eye over a period of one year.