Objective: To optimize the accuracy of intraoperative navigation for tumor resection in the
anterior and lateral skull base, we have used the intraoperative imaging (xCAT scanner,
Xoran Technologies, Inc., Ann Arbor, Michigan, USA).
Design: Prospective study.
Material and Methods: Reference markers were fixed into the bone (osteosynthesis screws) in five cases
or attached to a maxillary splint, which was carried during the intraoperative imaging
before the surgery, in six cases. The procedure was carried out isotropically with
a resolution of 0.4 mm with the VectorVision2 system (BrainLAB, Feldkirchen, Germany).
Results: The reference marker was attached at the Mayfield clamp or fixed directly to the
skull. Navigation was checked by using the identification of tumor margins and anatomical
landmarks (transition sphenoid sinus front wall to the nasal septum, on bony prominent
structures in the sphenoid sinus and the temporal bone) and cannot therefore be stated
in exact figures; however, the surgeons pointed out that the accuracy was very good:
the image of the screen to be extended with the pointer anatomical site was always
represented exactly, so that the overall accuracy of the system intraoperatively estimated
total of less than 1 mm.
Conclusion: An intraoperative imaging for navigation device can provide accurate intraoperative
precision and thus can be used as a reliable intraoperative diagnostic tool.
