The Viewing Wand is particularly useful when constant reference to the preoperative image is necessary. Locating small lesions no longer requires large exposures. After inputting all the diagnostic images into the work station, the wand is simply pointed at the head, the lesion located, the approach an trajectory planned and a minimally invasive approach option chosen. As one proceeds into the brain using the wand the exact present location in terms of the diagnostic image, is displayed on the computer screen. It will be possible to eventually input a host of data like physiological functions, angiograms and so on. Thus one can avoid dangerous areas. There is minimal disruption of normal brain, while approaching the tumor. This technique ensures accuracy and precision is the ability of a device to locate a point in space. Precision is the ability to return to a specific location. Constant checking and rechecking is possible. Like a spacecraft checking its position continuously by the Global Position Satellite, one knows exactly where one is at any point of time.
