Interactive image guided surgery using frameless stereotactic system

Interactive image guided surgery using frameless stereotactic system has been introduced in the neurosurgery for stereotactic localization without a standard frame. Viewing Wand system, one of clinically available frameless stereotactic system has been applied in 107 patients with various neurosurgical diseases in authors' hospital. To improve accuracy of this navigating system, we established the guideline of registration on the experimental basis of the phantom model. Though spatial accuracy of Viewing Wand system was acceptable in the clinical points of view, better accuracy can be expected when we use combined registration of external markers and random surface points as many as possible. Ninety-three percents of all cases were benefited by using the frameless stereotactic system. Especially the lesions located at eloquent area, subcortical, deep seated and intraventricular area can be approached safely by intraoperative navigation and real time feed back without damage of critical structures. Conclusively, image guided surgery using frameless stereotactic system is an useful tool in performing minimally invasive neurosurgery and locating anatomical structures and lesions to be removed.