1 Clinical Correspondence Cerebral Sinus Venous Thrombosis Mimicking Probable Paroxysmal Hemicrania: A Case Report Dev G. Mehta, DO; Jerry W. Swanson, MD, MHPE Key words: cerebral sinus venous thrombosis, paroxysmal hemicrania, trigeminal autonomic cephalalgia Abbreviation: PH paroxysmal hemicrania (Headache 2020;0:1-2) Cerebral sinus venous thromboses have been im- plicated in mimicking many of the primary headache disorders. We present the first case report of a cerebral sinus venous thrombosis presenting with symptoms suggestive of probable paroxysmal hemicrania (PH). A 77-year-old man with a past medical history of glaucoma and mixed, bilateral, conductive and senso- rineural hearing loss developed right-sided headaches. Four months prior to his consultation, the patient developed a constant, low grade holocranial head- ache. Over the next few days, the headache localized to the right side. The patient described the pain as constant with pressure with severe, superimposed stabbing. The ictal stabbing pain occurred in the ret- ro-orbital region. It was a constant stabbing sensation and occurred 5-6 times per day. Each episode lasted about 10-15 minutes. Interictally, he complained of a low-moderate grade right sided headache. Ipsilateral conjunctival injection, lacrimation, and aural fullness accompanied each episode of stabbing pain. The stab- bing pain was associated with restlessness and agita- tion. After development of the headache syndrome, alcohol ingestion would trigger an acute attack. This pattern continued for 2.5 months until it stopped. A month and a half later, the patient presented to our clinic for a consultation. At that time, he was com- pletely headache free and was able to drink alcohol without provoking severe, right-sided, and stabbing pain. His neurological exam was normal. Specifically, there was no papilledema or focal neurologic find- ings. Serologic work up including CBC, CMP, ESR, and thrombophilia labs were unremarkable. CT of the chest, abdomen, and pelvis were negative for malig- nancy. MRI and MR venogram of the brain revealed a thrombosis within the right transverse sinus which extended through the sigmoid sinus into the jugular vein (Fig. 1). Given the resolution of his headaches, a trial of indomethacin was not undertaken at the time. At the most recent follow-up, the patient has not had any recurrence of his symptoms and has been placed on anticoagulation for the thrombosis. Headache doi: 10.1111/head.13781 © 2020 American Headache Society Published by Wiley Periodicals, Inc. ISSN 0017-8748 Conflict of Interest: None Funding: None From the Department of Neurology, Mayo Clinic, Rochester, MN, USA (D.G. Mehta and J.W. Swanson). Address all correspondence to D.G. Mehta, Department of Neurology, Mayo Clinic, Rochester, MN, USA, email: dgmehta89@gmail.com Accepted for publication February 6, 2020.