Asian cerebral venous thrombosis registry: study protocol.

INTRODUCTION Cerebral venous thrombosis (CVT) is a well known but poorly reported entity. Most of the studies and registries related to CVT are reported from European countries. No large multi-center or multi- national data base or registry has been reported from Asian countries. CVT is not uncommon in Asia especially in south Asian subcontinent including India, Pakistan and Bangladesh. One study reported from India that CVT accounted for half of all strokes in the young and 40% of strokes in women. Review of CVT cases from Asian countries is suggestive of differences in risk factors profile and outcome in these patients as compared with European studies. These findings from multi- center data base in Asian countries will be extremely important in identifying risk factors for CVT in these countries. STUDY DESIGN This is a prospective observational study. We plan to enroll more than 1000 patients from at least ten Asian countries (about 40-50 centers). Patients will be enrolled prospectively and followed for six months. Primary outcome would be death or dependence as assessed by modified Rankin scale (mRS). Data will be collected on a pre-defined data form. There will not be any laboratory test, investigation or treatment specified by the study. Only results of routinely performed studies and treatments will be recorded. Patient (aged 16 or above) will only be included in study if they have diagnosis of CVT proven by magnetic resonance imaging (MRI), magnetic resonance venography (MRV), computed tomography (CT) venography and cerebral venography according to established criteria. Follow up visits will be performed at 6 months, 12 months, and yearly thereafter, preferably by direct interview and observations by the local investigators. OUTCOME Primary outcome is death or dependence (mRS >2) at the end of the follow-up period. Secondary outcomes are death and dependence at 6 months. Patients will be enrolled from January 2009 to June 2010.