Cluster headache presenting with orbital inflammation.

Acute, noninfectious orbital inflammations often defy a specific diagnosis despite a thorough medical evaluation and are grouped in the nonspecific diagnostic category of idiopathic inflammation of the orbit (pseudotumor). An atypical case of cluster headache presenting with intermittent migratory facial swelling and orbital inflammation, and 3 mm of exophthalmos simulating idiopathic orbital inflammation is presented. Although periobital pain is a frequent finding in patients suffering from cluster headaches, to the authors' knowledge this is the first reported case of orbital inflammation with cluster headache. After unsuccessful treatment directed at potential infectious and inflammatory causes, the patient responded well to methysergide, an established treatment for cluster headaches. A review of the known mechanism for this disorder, peripheral and central nervous system mechanisms of pain, and migratory angioedema reveals overlapping pathophysiology, clinical findings, and associated symptoms.