A case of extensive acute cerebral venous thrombosis. The child subsequently developed seizures on anticoagulation therapy. Excepting for the uncomplicated maxillary antral and ethmoid appearance, no other source of thrombosis could be found. The lumbar puncture confirmed the absence of any meningitis or encephalitis, and the prothrombotic workup was negative. All other possibilities were excluded and eventually, idiopathic cerebral venous thrombosis was considered as the most likely cause.

The dural venous sinuses and left cerebellar including cortical veins are markedly hyperdense and one can be fooled into thinking of acute subarachnoid hemorrhage and/or contrast administration based on the CT brain appearance. The trauma history is negative, and the CT brain study is a non-contrast study noted by the absence of any contrast within the intracerebral arteries and additionally the absence of any paranasal sinus 'enhancement'.