Hyperhomocysteinemia is a known risk factor for venous thrombosis. It results from low socioeconomic conditions secondary to deficient nutritional status, low plasma folate and vitamin B12 levels, which are associated with an increased risk of CVST in some developing countries.12,13 A small percentage (5.64%) of our patients had BD. The prevalence of BD is 16 in 100,000 people in Iran.14 The frequency of neurological manifestations in Inhibitors,research,lifescience,medical Behcet’s disease ranges from 5% to 30%.15 Borhani−Haghighi et al,16 reported that 22% of patients with Neuro-Behcet’s disease developed

CVST. This might justify the high frequency of the disease as an underlying cause of CVST in Iran. Some patients of this study had primary antiphospholipid antibody syndrome (APLS) and systemic lupus erythematosus (SLE). The role of antiphospholipid antibodies and other lupus anticoagulants in the evolution of CVST has been previously reported.17,18 Thrombophilia conditions including deficiency of proteins Inhibitors,research,lifescience,medical C and S appeared in 6.5% of the patients. One of our patients, who was also reported by Borhani−Haghighi et al,19 had a rare sporadic combined hyperhomocysteinemia and protein C deficiency. The mortality and morbidity rates in our patients were higher than some

previous studies. The mortality rate was 14.51% in the present study, whereas that of patients with Inhibitors,research,lifescience,medical CVST in an international study on cerebral vein and dural sinus ABT-199 in vivo thrombosis (ISCVT) was 8.3%.9 Higher mortality in the present study might be due to the referral nature of our center, which excluded patients with milder course as well as the lack of neuro-intensive care units. Presence of coma or stupor (P=0.001), parenchymal hemorrhage (P=0.005) Inhibitors,research,lifescience,medical at the time of admission, and cancer were common predictors of high mortality rate in this study and other previous studies.3,6,8,20 Increased morbidity in the present study (35.48%) compared to that of ISCVT (26.92%) may be attributed to retrospective nature of our study in a clinic-based Inhibitors,research,lifescience,medical follow-up. Headache, optic atrophy and focal neurological deficits were major sequels, which were similar to those

reported in Azin et al.3 and Hameed et al.21 Extracranial venous thrombosis in our study was approximately two times more than what was reported in a study by Ferro et al.6 (8.06% vs 4.3%). Predisposing Unoprostone factors for recurrent thrombosis were malignancy, postpartum state, OCP, BD, SLE, and APLS. This study sheds new light on the subject, and suggests using important methods including organ mobilization and prophylactic anti-coagulative drugs in patients with cerebral venous-sinus thrombosis. It also emphasizes prompt diagnosis and treatment of thrombophilic conditions to prevent thrombosis formation more than before. Conclusion The findings of the study indicate that the use of OCPs was a main factor associated with CVST.