Fig. 4
The standard approach vector superimposed on the 3D brain image of 35-year-old TLE patient. When the standard vector (white arrow) is expressed in the chiasmatico-commissural coordinate, where the horizontal plane is parallel to the sylvian fissure, it was oriented 51.0° posteriorly along the sylvian fissure (left) and 15.5° in inferiorly along the axis perpendicular to the Sylvian fissure (right).