A rare case of secondary paroxysmal hemicrania caused by a T1 nerve root schwannoma.

Introduction: Paroxysmal hemicrania (PH) is a rare headache disorder of severe intensity, which is classified within the group of trigeminal autonomic cephalalgias and is renowned for its prompt response to indomethacin. Objectives: Since its first description in 1974, only few cases of secondary PH have been published and even fewer with distinct lesions and a clear pathophysiological association. Methods: We here present a unique case of long-standing secondary PH, which resolved permanently after resection of a schwannoma of the T1 nerve root, which carries sympathetic projections to the periorbital region. Results: The current case stresses the importance of sympathetic/parasympathetic dysregulation in the pathophysiological origination of PH, which is far beyond purely central mechanisms. It is the first case ever published, which shows a quite remote peripheral pathology causing a trigeminal autonomic headache disorder. Conclusion: This case has important implications on a better understanding of the pathophysiology and future diagnostic workup of PH, which should ideally include imaging not only of the brain but also of the spine down to the thoracic level.