Orbital myositis posing as cluster headache

Objective: To describe the case of a patient with recurrent orbital myositis who was thought to have cluster headaches for 6 years. Design and Setting: Case report in an outpatient neuroophthalmology clinic. Patient: A 24-year-old man developed unilateral supraorbital pain, lacrimation, conjunctival hyperemia, nasal congestion, proptosis, and painful eye movements. The pain intensity varied over the course of each day and disappeared after 1 month. He had multiple attacks responsive to prednisone that were separated by months over the ensuing 6 years. Neuroimaging revealed an enlarged extraocular muscle. Conclusions: Overlap in symptoms between recurrent orbital myositis and cluster headache delayed the diagnosis in this patient. Orbital myositis should be considered in patients with atypical cluster headache characterized by proptosis, painful eye movements, and pain that does not completely resolve after 3 hours.