Endoscope-assisted far-lateral transcondylar approach to the skull base.

The far-lateral transcondylar approach was used in this cadaveric study in an attempt to evaluate the usefulness of endoscope-assisted microsurgery in this region of the skull base. The study was carried out using 4 latex-injected, formalin-fixed cadaver heads. After initial examination of intradural structures under an operating microscope, a zero degree 4 mm diameter solid-rod endoscope lens was introduced and guided into position under the direction of the operating microscope. Photographs of the regional anatomy were taken through this lens and through a 30 degree angled lens and compared to photographs of the anatomy taken through the microscope. Clear close-up views of the dural portals and intradural course of the cranial nerves were obtained using the endoscope. The endoscope was introduced through three corridors enclosed with cranial nerves, providing the surgeon with panoramic views of the vertebrobasilar arteries and anterior brainstem surface. The endoscope can be guided through narrow corridors and placed immediately adjacent to a region of interest at the skull base. It enables the surgeon to look around blind corners and work behind structures that are hidden from microscopic view.