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.