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.

Describes an integrated MINERVA system which meets demanding robotic requirements. The system incorporates a CT scanner and has 5 motorized axes equipped with nonreversible gears. The image processing facility operates on a SUN sparc workstation.< >

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. J Image Guid Surg 1:266–272 (1995) © 1996 Wiley-Liss, Inc.

At the 1989 meeting of the World Society for Stereotactic and Functional Neurosurgery in Maebashi, the authors presented the concept and design of a stereotactic neurosurgical robot. The first prototype has now been completed and has entered clinical testing. The characteristics are as follows. The robot is positioned behind the CT scan and operates inside the CT gantry. It is linked to the CT table and moves freely along its longitudinal axis, allowing for intraoperative scanning at any cranial level. The patient's body rests on the CT table, but the stereotactic headframe is fixed to the robot, allowing precise measurements of the head position under stereotactic conditions. During scanning, each CT slice appears immediately on the robotic workstation for selection of target and trajectory. In addition to the tool for automatic penetration of the skin, skull, and meninges, the robot is able to handle two other stereotactic instruments and to perform a complete stereotactic procedure without physical intervention by the physician. So far, depth electrodes and biopsy instruments have been developed for use by the robot. Since all parts of the robot were designed solely for stereotactic neurosurgery, integration of safety aspects was optimized. The first operations using an aspiration biopsy probe were successfully performed on 2 patients with malignant intracerebral cystic lesions on September 4, 1993.

We describe a robot capable of performing all procedures necessary to carry out a complete stereotactic neurosurgical operation under the control and supervision of a surgeon. The operation consists of the introduction of a small probe with diameter 2–3 mm through a hole without trepanation. The robot has been built and is now being tested and evaluated. The accompanying control software as well as various medical probes are either in development or partially tested. The installation will be able to carry out a complete intervention under the surveillance of a computed tomography scanner. In this article we emphasize the design choices required to eliminate gearing backlash in a crucial degree of freedom.

A robotized installation has been designed to perform complete stereotactic neurosurgical operations inside the CT-scan, including processing of the scanner images, positioning of the robot arm aiming at the target point, and manipulation of the different probes. The first prototype of the robot has entered a phase of programming and testing while various stereotactic instruments are being completed. The robot has been described in [1]. The development of specific tools is the main subject of this paper.

Stereotactic neurosurgery consists of the introduction of a small probe with a diameter of 2-3 mm through a hole drilled in the skull, in order to reach 'blindly' a point inside the brain which has previously been located, on scanner sections and marked by means of a reference system on the patient's head. The robot described has been built, partial tests have been carried out on cadavers and validated (positioning, skin incision and bone drilling, etc.. . .). The paper briefly explains the general design. Significant studies are being made concerning safety, reliability and robot-surgeon dialogue. The difficulty of developing a robot for surgery lies in the multidisciplinary aspect: problems in mechanics, electronics, computing, medicine, surgery and sterilization had to be tackled.<>

The design of a robot for functional stereotactic surgery which is under construction in our laboratory is described. The main features include operation inside the computed tomographic (CT) scanner, the possibility of intraoperative CT scanning and complete handling of the stereotactic probes by the robot.