Telerobotics in medicine and surgery

Surgical Robots

Information technology and robotics have been integrated into interventional medicine for over 25 years. Their primary aim has always been to provide patient benefits through increased precision, safety, and minimal invasiveness. Nevertheless, robotic devices should allow for sophisticated treatment methods that are not possible by other means. Several hundreds of different surgical robot prototypes have been developed, while only a handful passed clearance procedures, and was released to the market. This is mostly due to the difficulties associated with medical device development and approval, especially in those cases when some form of manipulation and automation is involved. This chapter is intended to present major aspects of surgical robotic prototyping and current trends through the analysis of various international projects. It spans across the phases from system planning, to development, validation, and clearance.

Surgical Robots

Information technology and robotics have been integrated into interventional medicine for over 25 years. Their primary aim has always been to provide patient benefits through increased precision, safety, and minimal invasiveness. Nevertheless, robotic devices should allow for sophisticated treatment methods that are not possible by other means. Several hundreds of different surgical robot prototypes have been developed, while only a handful passed clearance procedures, and was released to the market. This is mostly due to the difficulties associated with medical device development and approval, especially in those cases when some form of manipulation and automation is involved. This chapter is intended to present major aspects of surgical robotic prototyping and current trends through the analysis of various international projects. It spans across the phases from system planning, to development, validation, and clearance.

Telepresence surgery: first experiences with laparoscopic radical prostatectomy

The concept of an intelligent steerable surgical instrument system has been described by various authors. Since 1998, telesurgical minimally invasive procedures have been performed with the da Vinci system, mainly for cardiac bypass surgery. We present our initial experience using the device for robot-assisted laparoscopic radical prostatectomy. The intuitive surgical system consists of two main components: the surgeon's viewing and control console with 3D-imaging, and the surgical arm unit that positions and manoeuvres detachable surgical instruments. These instruments are introduced via two 8 mm trocars and allow movements in all six degrees of freedom (DoF). The surgeon performs the procedure while seated at the console holding specially designed instruments. Highly specialised computer software and mechanics transmit the surgeon's hand movements exactly to the microsurgical movements of the manipulators at the operative site. The system used is a W-shaped five trocar arrangement, with the robot's arms at the lateral trocars (8 mm) and two assistant trocars medially (10 mm). A sixth trocar was used in the right suprapubic area for retraction of the gland (Foley catheter). The left assistant used different instruments, such as bipolar forceps, Ultracision, and Endoclip, wheras the right assistant mainly used the suction–irrigation device. The Intuitive System was attached after trocar placement and exposure of Retzius' space. We treated six patients (two pT2, four pT3, median Gleason score 6). The operating room time averaged 315 (range 242–480) min, including pelvic lymph-node dissection. No intra-operative complications occured, one patient required transfusions. There were no positive margins, median catheter time was 5 days. Three patients were completely continent after 1 month. Telerobotic laparoscopic radical prostatectomy is feasible. There is a learning curve with the device, mainly due to the magnification, 3D image and lack of tactile feedback. However, the experienced surgeon can become familiar with the device after a short time. There is still a need for further development of instruments for urological procedures.

Robotics and telesurgery – an update on their position in laparoscopic radical prostatectomy

Laparoscopy is handicapped by the reduction of the range of motion from six to only four degrees of freedom. In complicated cases (i.e. radical prostatectomy), there is often a crossing of the hands of surgeon and assistant. Finally, standard laparoscopes allow only 2D-vision. This has a major impact on technically difficult reconstructive procedures such as laparoscopic radical prostatectomy. Solutions include the understanding of the geometry of laparoscopy, but also newly developed surgical robots. During the last five years, there has been an increasing development and experience with robotics in urology. This article reviews the actual results focussing on the benefits and problems of robotics in laparoscopic radical prostatectomy. Own experiences with robot-assisted surgery include more than 1200 laparoscopic radical prostatectomies using a voice-controlled camera-arm (AESOP) as well as six telesurgical interventions with the da Vinci-system. Substantial experimental studies have been performed focussing on the geometry of laparoscopy and new training concepts such as perfused pelvitrainers and models for simulation of urethrovesical anastomosis. The recent literature on robotics in urology has been reviewed based on a MEDLINE/PUBMED research. The geometry of laparoscopy includes the angles between the instruments which have to be in a range of 25 degrees to 45 degrees ; the angles between the instrument and the working plane that should not exceed 55 degrees ; and the bi-planar angle between the shaft of the needle holder and the needle which has to be adapted according to the anatomical situation in range of 90 degrees to 110 degrees . 3-D-systems have not yet proved to be effective due to handling problems such as shutter glasses, video helmets or reduced brightness. At the moment, there are only two robotic surgical systems (AESOP, da Vinci) in clinical use, of which only the da Vinci provides stereovision and all six degrees of freedom (DOF). To date, more than 3000 laparoscopic radical prostatectomies have been performed worldwide at 92 centres with this system. The main advantage of the system represents the translation of open surgical skills to laparoscopy. Despite recent development of basic tools (e.g. bipolar forceps) for the da Vinci robot, investment and maintenance costs still represent the major problem of the device. Additionally, the device does not provide any haptic sense (i.e. tactile feedback). Robotic surgery represents a turning point of surgical research. However, broad use of robotic systems is limited mainly because of the high investment and running costs. Interestingly, more than in the field of cardiac surgery, there seems to be a need for telemanipulators in urology, mainly to reduce the learning curve of standard laparoscopy. However, new training concepts used in combination with mono-tasking computerized robots (AESOP) have proved their efficacy associated with a significant cost reduction.

Robotic Surgery: Urologic Implications

Current medical robots have nothing in common with the anthropomorphic robots in science fiction classics. They are in fact, manipulators, working on a master-slave principle. Robots can be defined as "automatically controlled multitask manipulators, which are freely programmable in three or more spaces." The success of robots in surgery is based on their precision, lack of fatigue, and speed of action. This review describes the theory, advantages, disadvantages, and clinical utilization of mechanical and robotic arm systems to replace the second assistant and provide camera direction and stability during laparoscopic surgery. The Robotrac system (Aesculap, Burlingame, CA), the First Assistant (Leonard Medical Inc, Huntingdon Valley, PA), AESOP (Computer Motion, Goleta, CA), ZEUS (Computer Motion), and the da Vinci (Intuitive Surgical, Mountain View, CA) system are reviewed, as are simple mechanical-assist systems such as Omnitract (Minnesota Scientific, St. Paul, MN), Iron Intern (Automated Medical Products Corp., New York, NY), the Bookwalter retraction system (Codman , Somerville, NJ), the Surgassistant trade mark (Solos Endoscopy, Irvine, CA), the Trocar Sleeve Stabilizer (Richard Wolf Medical Instruments Corp., Rosemont, IL), and the Endoholder (Codman, Somerville, NJ).

Robotic and telesurgery: will they change our future?

In urology, at the end of the last millennium, there was an increasing use of computerized technology, extracorporeal shock wave lithotripsy, microwave therapy and high-energy focused ultrasound. However, experience with manipulating robots in urological surgery is still very limited. Laparoscopic surgery is handicapped by a reduction of the range of motion because of the fixed trocar position. The da Vinci system is the first surgical system to address all these problems adequately. The system consists of two main components: the surgeon's viewing and control console with three-dimensional imaging and the surgical arm unit that positions and manoeuvres detachable surgical instruments. The surgeon performs the procedure seated at the console holding specially designed instruments. Telerobotic laparoscopic radical prostatectomy provides advantages such as stereovision, dexterity and tremor filtering, but there is a learning curve with the device, mainly because of the magnification, the three-dimensional image and the lack of tactile feedback. However, after only a short period of time, the experienced surgeon is able to become familiar with the device. The impact of robotics in urological surgery is therefore very promising, and we are convinced that it will totally change the future of urological surgery.

Advances in ultrasound: from microscanning to telerobotics

This paper is in memory of W V Mayneord (1902-1988). Experiments conducted in Mayneord's laboratory were amongst the first to show that ultrasound had diagnostic potential. Now, one in every four imaging studies uses ultrasound. Amongst numerous contemporary advances, microscanning is concerned with imaging subcentimetre size volumes of tissue in three dimensions with 10-100 microns resolution. The traditional approach is by pulse echo imaging, with a focused ultrasonic beam in the frequency range 20-100 MHz. This approach may be complemented by ultrasonic CT (to correct for attenuation and speed variations), reflex transmission imaging (to provide attenuation data) and synthetic aperture scanning (to decrease imaging time). Harmonic microscanning may reduce artefacts, and elasticity imaging may also be possible. Microscanning is likely to have applications in pathology and in the operating room, for trackless microintervention, in molecular biology and drug studies, and in experimental imaging of small mammals including, in particular, the mouse. Robotics is the engineering science concerned with devices that are able to execute tasks usually performed by humans. Two procedures, ultrasonically guided biopsy and ultrasonic laparoscopy, are being used to demonstrate the feasibility of telerobotics. The approach is that of telepresence, as distinct from supervisory control or virtual reality. Problems associated with image compression and communications latency are identified. Although incremental developments in medical ultrasound have resulted from clinical pull, major advances have, in general, been due to technical push.