Development of a computerized microstereotaxic method for localization and removal of minute CNS lesions under direct 3-D vision

Abstract

✓ The authors describe a novel stereotaxic method for the removal of minute lesions of the central nervous system (CNS). With the development and refinement of computerized tomography (CT), such small lesions can be detected by noninvasive (x-ray) scanning with computer processing of the data. Using a G E 7800 scanner system and a PDP 11/45 computer, data processing of various kinds is possible. Multiple computer programs have been developed to enhance regions of interest on CT scans by magnification, three-dimensional reconstruction, and digital processing. These data are then used to calculate a stereotaxic approach to a CNS lesion. A head fixation system has been devised to enable information transfer from a CT scan to the stereotaxic surgical system. Newly developed instruments are mounted on a micromanipulator for guidance at the operative site. These include stereo endoscopes with xenon arc illumination, a tissue expander for exposing the operative area, a radiation tracer probe, a rotary extractor, and instruments for operating and removal of blood from a small intracerebral hemorrhage. The micromanipulator for guiding the tactical instruments is, in turn, mounted on a stereotaxic guide mechanism which accurately defines all areas of the cranium in three-dimensional coordinates. The combination enables the site of the lesion, the three-dimensional coordinates of which have been located by CT scan, to be accurately approached by the stereotaxic guide/micromanipulator assembly.