Indications for computer-assisted treatment of cranio-maxillofacial tumors.

OBJECTIVE Ablative tumor surgery requires detailed planning using computed tomography (CT) or magnetic resonance imaging (MRI). Reconstruction following tumor resection is dependent on reliable information for choosing the correct type and volume of grafts and predicting the outcome. This study evaluates the benefit of and the indications for computer-assisted surgery in the treatment of cranio-maxillofacial tumors. MATERIALS AND METHODS Based on a CT or MRI data set, the STN Navigation System (Stryker-Leibinger) was used for preoperative planning, intraoperative navigation, and postoperative control of radical tumor resection and primary and secondary reconstruction. Tumor resection was preoperatively planned and intraoperatively navigated. Preoperatively, the required soft and hard tissue were measured using the mirrored data set of the unaffected side of the facial skeleton; the size and location of the graft were chosen virtually. Intraoperatively, contours of transplanted tissues were navigated in accordance with the preoperatively simulated reconstructive result. RESULTS Computer-assisted treatment was successfully completed in all cases of radical tumor resection, and safety margins outlined preoperatively could be precisely controlled during tumor resection. Reconstruction was designed and performed exactly as virtually planned. CONCLUSIONS Image-guided treatment improves preoperative planning by visualization of the individual anatomy and the intended reconstructive outcome, and by objectivation of the effect of adjuvant chemo-/radiotherapy. Intraoperative navigation makes radical tumor surgery more reliable by showing the determined safety margins, preserving vital structures, and guiding reconstruction to preplanned objectives.