Single-step fronto-orbital resection and reconstruction with individual resection template and corresponding titanium implant: a new method of computer-aided surgery

In the cranio-maxillofacial field, computer-aided surgery based on computed tomography (CT) data is becoming more and more important. Navigation syste ms, which allow the precise intraoperative orientation of surgical instrume nts, can be used for greater accuracy in determining resection margins of t umours. These techniques support ablative procedures very well, but defect reconstruction still remains a problem. In contrast, computer-aided design (CAD) and computer-aided manufacturing ( CAM) systems allow the construction and fabrication of individual templates for bone resection based on coherent numerical 3-D models. The template de termines the exact pathway of an oscillating sam so that the planned extent of the resection and, if necessary, also the orientation of the cutting pl ane are verified. An individual titanium implant is prefabricated with a ge ometry fitting to that of the template. This implant closes the bone defect so that the contour is reconstructed precisely and individually. This new method was used for the first time for a single-step resection of a meningioma and defect-reconstruction. The tumour which had infiltrated th e frontal bone resulting in a protrusion. Fronto-orbital resection and inse rtion of the titanium implant worked precisely as planned, so that this met hod offers promising new applications in the field of computer-aided surger y.