[The possibilities and limitations of the neuronavigation method in the treatment of intracranial pathology, on the basis of anatomic registering markers and preoperative magnetic resonance imaging].

INTRODUCTION: The evaluation of technical parameters of the system and the evaluation of the influence of changing intraoperative conditions on the accuracy of the indications of the neuronavigational system has the key meaning in the effectiveness on the work ofa neurosurgeon. On the other hand the employment of neuronavigation during an operation on the brain allows to get an insight into the dynamics and directions of the shifts of individual brain structures in regard to themselves and hard integuments.

MATERIAL AND METHODS: In the experimental part of the work an analysis was done of the theoretical and actual accuracy of indications of the neuronavigational system obtained after the registering process in modal and clinical conditions. In the clinical part of the work, during the operations of 69 patients with the use of the neuronavigational system an analysis was done of the dynamics and the direction of shifts of the brain's surface and the boundaries of pathological focus in regard to the placement and volume of the pathological focus, volume of the peritumorous edema and the usage of the escape of the cerebrospinal fluid, as well as resulting from those shifts the divergence in the indications of the neuronavigational system.

RESULTS AND CONCLUSIONS: A smaller accuracy of the neuronavigational system in clinical than in modal conditions was proved. Anatomical registering markers cause the shifts of areas of greatest accuracy to the face area of patients, not including in its range the back sides of the head and there localized 65.4% of pathological focuses. In model and clinical conditions significant differences between computer error of the RMSE registering process and the marker localization error empirically defined were proved. In result of the analysis of the shifts of the cerebral cortex during the operation of tumors: Meta, Astr. II, Astr. III, GBM, vascular and intrachamberal it was proved that the peritumorous edema, the volume of the pathological focus and the escape of the cerebrospinal fluid statistically significantly influence the shifting of the surface of the cerebral cortex in the craniectomy hole. In effect of the analysis of the shifts of the borders of pathological focuses it was found that the direction of the shifts of borders of pathological focus covered the direction of shifts of the surface of the brain after meningeal decompression, though the value of shifts was incomparably smaller.