Suitability and Limitations of Pointer-Based and Microscope-Based Neuronavigational Systems for Surgical Treatment of Intracerebral Tumours – a Comparative Study of 66 Patients

Summary Frameless neuronavigational systems are a recent novelty for a precise approach to intracerebral tumours in open surgery. In this study 66 patients with a variety of intracranial tumours in various locations underwent surgical resection with neuronavigational guidance. Two different neuronavigational systems ‐ the arm- and pointer-based ISG viewing wand and the miroscope-based MKM system ‐ were compared for four different indications. Neuronavigation was used (a) in multiple tumours, e. g. brain metastases, (b) in solitary cortical or subcortical tumours located in eloquent brain areas, e. g. motor cortex or speech region, (c) in deep-situated brain tumours, including brain stem neoplasms, and (d) in infiltratively growing tumours to define the borders of the lesion. Using taped skin markers (MKM system) and a surface-fit algorithm (viewing wand) for registration, an accuracy of 1 to 2 mm deviation was achieved, which was sufficient for removal of all of the intracranial neoplasms investigated. Both systems proved to be