Abstract
A wide range of diagnostic imaging techniques are used as positional measuring devices for the localization stage of stereotatic neurosurgery. Positional mapping from the image system to the surgical reference frame is achieved using a variety of designs of fiduciary systems. Standard projection radiography, computed tomography, digital radiography and fluoroscopy, and magnetic resonance imaging are used to plan and accurately guide interventional neurosurgical procedures. A general summary of the applications of stereotactic techniques is presented. The techniques involved and the design principles of the fiduciary systems used are discussed, along with the scientific limitations and accuracies of the various systems.