INTERACTIVE IMAGE GUIDANCE IN SKULL BASE SURGERY USING AN OPTOELECTRONIC DEVICE

The applicability of an image guidance frameless system based on an op to-electronic sensor device in skull base surgery was explored in this study. Five embalmed heads with external fiducial markers placed in n oncoplanar points were scanned (CT scan) and different skull base appr oaches were reproduced in these specimens. The opto-electronic system is comprised of an infrared cameral a local rigid body, and a 24-light -emitting diode probe attached to different surgical instruments. DOS- based calibration and transformation software and Unix-based surgical planning software were also used. The anatomic landmarks identified du ring the dissection were matched with the corresponding points derived from computed tomographic (CT) scans. This information allowed the su rgeon to develop a three dimensional representation of the surgical fi eld and to anticipate the next anatomic structure encountered during t he dissection. This infrared device operated in real time, is not affe cted by external factors with regard to its accuracy, and does not int erfere with standard neurosurgical techniques. This frameless system i s helpful in minimizing the risk of morbidity and provides an accurate guide during the approach, as well as unobstructed access to the surg ical field.