Fig. 1

3D Vessel Model. The selection of the start and end points for extraction in the sigmoid sinus and superior sagittal sinus can be seen in a and b, respectively. The resultant 3D VR vessel model with 2 points of interest (labelled 1 and 2) and the skull model, which is used to register the MRV model with fluoro, are pictured in c and d. A sagittal 3D MIP of the venous anatomy with the vessel trace highlighted in green and the start and end points defined can be seen in e