Migraine-like headache in cerebral venous sinus thrombosis

A 20-year-old female, university student presented with severe, throbbing, unilateral headache, nausea and vomiting that started 2 days ago. The pain was aggravated with physical activity and she had photophobia. She had been taking contraceptive pills due to polycystic ovary for 3 months. Cranial computed tomography was uninformative and she was considered to have the first attack of migraine. She did not benefit from triptan treatment and as the duration of pain exceeded 72h further imaging was done. Cranial MRI and MR venography revealed a central filling defect and lack of flow in the left sigmoid sinus caused by venous sinus thrombosis. In search for precipitating factors besides the use of contraceptive pills, plasma protein C activity was found to be depressed (42%, normal 70–140%), homocystein was minimally elevated (12.7μmol/L, normal 0–12μmol/L) and anti-cardiolipin IgM antibody was close to the upper limit.