Cerebral venous sinus thrombosis: a late sequel of invasive fibrous thyroiditis

Riedel's invasive fibrous thyroiditis (IFT) is a rare disease of unknown etiology characterized by a dense fibrosis involving the thyroid gland and its surrounding tissues. Clinically, patients present with a stony hard goiter frequently associated with compressive symptoms. Involvement of the surrounding neck structures by IFT can lead to various clinical sequelae. We report the case of a 55-year-old woman with known IFT who developed thrombosis in the right internal jugular vein that progressed to the right sigmoid, transverse, and superior sagittal sinuses. IFT could have predisposed to cerebral venous sinus thrombosis by causing venous stasis, vascular damage and possibly a hypercoagulable state. To our knowledge, this is the first report of cerebral venous sinus thrombosis that developed as a complication of IFT.