Cord sign: cortical venous thrombosis evolving to a ring enhancing lesion.

Cortical venous thrombosis can present with non-specific findings including headaches and seizures. Subsequent cortical infarction has a variety of radiological appearances. The authors describe the diagnostic challenge of a case of cortical venous thrombosis presenting with focal motor seizures where imaging showed a ring enhancing lesion and the 'cord sign' and underwent a stereotactic brain biopsy.