From the Idea to Its Realization: The Evolution of Minimally Invasive Techniques in Neurosurgery

Figure 12

Clarke’s concept of Cartesian localization. Every point is defined as a distance to three perpendicular planes. Horizontal plane defined as inferior orbital plane running through both acoustic meatus. The frontal plane is perpendicular to the horizontal plane and running through both acoustic meatus. Sagittal plane is perpendicular to the two other planes and divides the head in the midline in two equal parts.