Robotics and telemanipulation technologies for endoscopic surgery. A review of the ARTEMIS project. Advanced Robotic Telemanipulator for Minimally Invasive Surgery.

In endoscopic surgery, the ability to guide the instrument is significantly decreased compared with open surgery. Rigid laparoscopic instruments offer only four of the six degrees of freedom required for the free handling of objects in space. Robotics technology can be used to restore full mobility of the endoscopic instrument. Therefore, we designed a master-slave manipulator system (ARTEMIS) for laparoscopic surgery as a prototype. The system consists of two robotic arms holding two steerable laparoscopic instruments. These two work units are controlled from a console equipped with two master arms operated by the surgeon. The systems and its components were evaluated experimentally. Laparoscopic manipulations were feasible with the ARTEMIS system. The placement of ligatures and sutures and the handling of catheters were possible in phantom models. The surgical practicability of the system was demonstrated in animal experiments. We conclude that robotic manipulators are feasible for experimental endoscopic surgery. Their clinical application requires further technical development.

The medical engineering program of Forschungszentrum Karlsruhe.

The research activities of the Forschungszentrum Karlsruhe on minimally-invasive surgery (MIS) have for several years improved techniques and instrumentation for different types of MIS. Many types of instruments and robotic devices have been developed and new techniques implemented. In this paper we present the most recent results from our different projects, such as endoscopic heart surgery, tracking systems, a camera guidance device, telemanipulator systems, minimally-invasive breast biopsy in closed-bore MRI, endoscopic training simulators and developments using smart materials (e.g. Nitinol).

Robotics and allied technologies in endoscopic surgery.

The human hand-arm system provides seven degrees of freedom for the manipulation of objects in space. In open surgery these motion axes can be used fully when guiding the surgical instrument. In endoscopic procedures the surgical instrument is fixed to the point of trocar insertion, resulting in only four degrees of freedom. This leads to a loss of instrumental functionality in endoscopic procedures. Robotics and telemanipulator technology can be used to restore the full spatial mobility of the endoscopic instrument. A functional model of an endoscopic master-slave manipulator system has been developed and is under experimental surgical evaluation. Allied technologies include new tactile sensor and vision systems that can enhance the application of robotic systems in surgery for the future.

Experimental telemanipulation in endoscopic surgery.

Today's rigid endoscopic instruments limit the intracorporeal mobility of the surgical tool and are a severe impediment for the further spread of endoscopic techniques in operative medicine. Since 1992 flexible, steerable instruments with additional links for pivoting and rotating the tip have been developed and experimentally evaluated. The latest versions of this series of instruments are equipped with electromotors for better handling. The next aim in this development is a fully mobile telemanipulator with six motion axes dedicated to use in endoscopic surgery. Its first tests are planned for 1995. For successful operation of an electric telemanipulator, the man-machine interface (MMI) is of cardinal importance. For the definition of surgical requirements for the MMI, a conventional master-slave manipulator designed for technical application was modified for use in guiding a laparoscopic instrument. Master and slave sites of the system were 1.3 km apart and linked by means of a fiber-optic cable. Using this modified telepresence system, remote laparoscopic cholecystectomy was feasible in a phantom model. In a standardized test series using a test parcours, different parameters of the control system were modified, and their influence on the execution time of the parcours tasks was recorded. Well-suited parameter configurations were found and allowed experimental verification and completion of the important aspects of our concepts for development of an endoscopic manipulator MMI.

[Laparoscopic technique--which developments are possible?]. / Laparoskopische Technik--welche Entwicklungen sind möglich?

The progress of laparoscopy is influenced by both the medical and technical aspects. The development of endoscopes and various rigid instruments has increased the indication options. Nevertheless, several drawbacks remain, e.g. the limited spatial view, the missing sense of touch, and reduced mobility in the operation area. New 3D visual systems now introduce spatial view. Flexible instruments are being developed that allow thorough examination of organs. While these enhancements are now becoming available, research and development are making progress and preparing the next steps. One vision is the development of a telepresence and telemanipulation system. With it, at the patient's side we will have an endoscope guidance system and several instrument guidance systems, which will be telemanipulated from a control station. At the control station, a 3D picture from the operation scene, together with virtual reality simulation pictures will be available. Force reflection as well as palpatory sensing information will be readily available to the telesurgeon. These new developments will improve the quality of the surgery for the benefit of both the patient and surgeon. Furthermore, the training of new surgeons will be eased by the use of sophisticated simulators using virtual reality techniques. These and further technical developments will not only lead to an improvement in current laparoscopy procedures, but it can be expected that additional procedures will be developed that are not yet possible and accessible to laparoscopy.

Intelligent surgical instrument system ISIS. Concept and preliminary experimental application of components and prototypes.

The recent progress in endoscopic surgery, which is highlighted by the complexity of fundoplication, stomach surgery and colorectal surgery, has revealed major restrictions with difficult surgical manipulations. Mobilisation, dissection and suturing techniques are hampered mainly by the limited degrees of freedom of the conventional rigid instruments (translation along and rotation around the longitudinal axis and the limited play in the access channel). The frequent interchange of instruments such as coagulation forceps, scissors and suction-irrigation probe is time-consuming. We have established an interdisciplinary development model with the aim of improving surgical technology, instrument systems, the operation theatre and its environment. Concepts of electronic instrument control and sensoric feedback, and the features of the surgical man-machine-interface are described. The first prototypes of an intelligent steerable instrument system, ISIS, and its optional effectors, e.g. semiautomatic sewing device and multifunctional coagulation instrument, were tested in phantom and animal experiments. System analysis will lead to specially designed operating theatres (minimal invasive surgical operating system MINOS).