Deep cerebral sinovenous thrombosis precipitated by high-altitude exposure.

Cerebral sinovenous thrombosis (CSVT) is rare and occurs in three to four persons per one million of population per year1. Deep cerebral venous system involvement is present only in 10% of CSVT2. Thrombosis of deep cerebral veins presents with headache, encephalopathy, and variable focal deficits, and is associated with increased risk of death or dependence if not recognized and treated promptly3. Various risk factors have been identified for deep cerebral sinovenous thrombosis (DCSVT), of which oral contraceptive use, pregnancy and puerperium account for two thirds of these cases4. Exposure to high altitude precipitating DCSVT is extremely rare with only one prior case report published in the English literature5. We report a case of a young male who developed DCSVT at high altitude.