Tolosa-Hunt syndrome presenting with features of a trigeminal autonomic cephalalgias and pituitary enlargement.

Tolosa-Hunt syndrome is understood as a steroid-responsive, relapsing-remitting, unilateral headache disorder associated with ipsilateral cranial neuropathies, of a probable granulomatous aetiology. The diagnosis is made clinically from the history and examination, supported by appropriate imaging. Here the authors report a case of Tolosa-Hunt syndrome with a headache phenotype mimicking a trigeminal autonomic cephalalgias (hemicrania continua), and serial MRI studies showing a stable enlarged pituitary. Due to her initial lack of clinical signs, she was diagnosed with chronic migraine, revised to hemicrania continua based on indomethacin response, then revised back to chronic migraine. Her final diagnosis was achieved after she developed a left cavernous sinus syndrome 4 years into her disease course. This case shows that Tolosa-Hunt syndrome may present with a non-side-locked headache and delayed development of clinical signs. Clinicians should also maintain a high degree of suspicion when faced with incidental MRI findings.