Robotic three-dimensional positioning of a stimulation electrode in the brain.

Functional stereotactic cerebral operations are currently performed with straight electrodes. After physiological exploration, correction of the initial target is frequently necessary and requires multiple penetrations of the brain. This paper describes a robotic three-dimensional electrode probe that can reach targets located within a cylindrical volume from a single approach trajectory. It has been mounted on the neurosurgical robot Minerva, and includes a string electrode, which can protrude out of the side window of a straight cannula and offers a high intrinsic accuracy of 0.25 mm. A simple man-machine interface allows the surgeon to select reference and target points and to activate the probe from a graphics workstation. This paper also analyzes the accuracy of the probe as well as of the whole operating system, food gelatin being used to simulate brain matter.

Neurosurgical robot Minerva: first results and current developments.

We describe the development and approach to clinical application of the neurosurgical robot Minerva, including the mechanical structure of the robot and the software developed to perform intracranial neurosurgical operations with accuracy, smoothness, and safety. The first eight operations have been undertaken on patients requiring stereotactic brain biopsy. We describe the ongoing developments, including improved sterilization features, force sensors, nonlinear electrostimulation probe, and implantation of living encapsulated cells, all of which have entered a test phase. The goals are increased safety and capability to perform simple three-dimensional operations. This research should ease the way for new complex operations that are difficult to perform manually today.