Purpose: To introduce a novel microstereotactic frame, called the Microtable, consisting of a tabletop that mounts on bone-implanted spherical markers. The microtable is customized for individual patient anatomy to guide a surgical instrument to a specified target.
Methods: Fiducial markers are bone-implanted, and CT scanning is performed. A microtable is custom-designed for the location of the markers and the desired surgical trajectory and is constructed using a computer-numerical-control machine. Validation studies were performed on phantoms with geometry similar to that for cochlear implant surgery. Two designs were tested with two different types of fiducial markers.
Results: Mean targeting error of the microtables for the two designs were 0.37 +/- 0.18 and 0.60 +/- 0.21 mm (n = 5). Construction of each microtable required approximately 6 min.
Conclusions: The new frame achieves both high accuracy and rapid fabrication. We are currently using the microtable for clinical testing of the concept of percutaneous cochlear implant surgery.