This case demonstrates extensive dural venous sinus thrombosis and its appearance on CT and MRI. Note that even in such an 'obvious' example there are pitfalls: CTV must be windowed correctly and adequate venous opacification obtained to distinguish hyperdense clot form contrast. Familiarity with normal appearance of slow flow / thrombus on various sequences is required; knowledge of the venous anatomy is needed to interpret phase contrast MRV.