Fig. 4

An example of an oligodendroglioma with a transformed region. The transformed region is demonstrated by the enhancement on the navigation T1 with contrast MRI (movement artefact of the patient) (a) and the corresponding hyperechogenic area on the i3DUS image (b). On these images, the navigation tool is represented by the blue line and its tip by the yellow circle. The projected tip extension is shown as a continuation of this line