Partial empty sella in a woman with cerebral venous sinus thrombosis: A rare presentation of polycythaemia rubra vera.

We report the case of a 59 year old woman who presented with a six week history of worsening bifrontal headache. On CT brain the only abnormal finding was a partially empty sella potentially indicative of increased intracranial pressure. MRI found a large cerebral venous sinus thrombosis in the superior sagittal sinus. Blood tests and a bone marrow biopsy revealed a diagnosis of JAK2 positive primary polycythaemia rubra vera. The lack of sensitivity and specificity of CT in the diagnosis of CVST should engender a low threshold for MRI in patients with risk factors and/or non-diagnostic abnormalities on initial CT. Management of this dual pathology involves both the immediate treatment of the thrombus with heparin bridging to warfarin and the long treatment for polycythaemia involving repeat venesections and cytoreductive therapy.