Review Article CURRENT ROLE OF ROBOTICS IN UROLOGY Ashish Sabharwal*, Suvajit Pradhan** and Anant Kumar*** *Registrar,** Senior Registrar ,*** Senior Consultant, Department of Urology and Renal Transplantation, Indraprastha Apollo Hospitals, Sarita Vihar, New Delhi 110 076, India. Correspondence to: Dr. Anant Kumar, Senior Consultant, Department of Urology and Renal Transplantation, Indraprastha Apollo Hospitals, Sarita Vihar, New Delhi 110 076, India. e-mail: [email protected] The most commonly used robotic device in Urology is the Da Vinci® system. This robot consists of three or four arms, one of which is used to hold and manipulate the laparoscopic camera while the others are used to manipulate specialized laparoscopic instruments with Endowrist® technology that allows 7 degrees of freedom. Robot is currently used primarily for radical prostatectomies where complex dissection and reconstruction can be performed in less than 2 hours with excellent outcomes. There is a progressive increase in the number of surgeries being performed by this device, which allows laparoscopy naive surgeons to offer the benefits of minimally invasive surgery to their patients. The other surgeries where this device has been used to benefit are pyeloplasty, cystectomy with urinary diversion, nephrectomy and ureteric re-implant. The principal drawbacks of the device are the steep cost of machine and disposables. However, the benefits achieved in terms of improved surgical precision, magnified 3 dimensional vision, scaling of movements, remote telerobotic surgery and as a teaching tool will help the robot establish a definitive place in the urologic armamentarium. Key words: Robotic Surgery, Da Vinci ®, Urology, Telerobotic. HISTORY OF ROBOTICS Automated endoscope system for optimal positioning (AESOP) from computer motion (Goleta, CA) was the first THE term robot is derived from a Czech word robota surgical robot to get food and drug administration (FDA) meaning ‘forced labor.’ The concept of robot can be traced approval for clinical use in 1993. The AESOP system is six back to 3000 b.c. The famous renaissance artist Leonardo degrees of freedom (DOF) of movements’ robotic arm that Da Vinci was said to have a mechanical lion that walked and mimics form and function of human arm to position an roared [1]. endoscope. The arm can be controlled either by a foot pedal; or by hand control; or voice command. Robots as we know them today were developed after World War II due to increased need of automation in Stanford Research Institute (SRI, Stanford, CA) automobile. General motors were the first major companies developed a tele-presence surgical system for open surgical to ever use a robot in 1961. procedures [3]. This system combined advances in remote manipulations with basic force feedback, stereoscopic Orthopedics and neurosurgery were the first specialties imaging, multimodal sensory feedback, and ergonomic to test the concept that the robots may be more precise than design. humans. An orthopedic system RobotDoc (Integrated Surgical Systems, Sacramento, CA) was used during Intuitive SurgicalTM (Mountain View, CA) was total hip replacement surgery [2]. In early 1980s with founded in 1995. They licensed technology and hired introduction of good optics, video equipment, and appro- engineers from SRI, MIT, and IBM. The first prototype was priate instrumentation general surgeons started exploring built in 1996 for animal trials. Second prototype was tested new vistas of laparoscopic surgery in an attempt to minimize on humans in Belgium in 1997. The alpha prototype of the trauma associated with their surgical procedures. daVinci SystemTM was used for cardiac procedures in However, limitations of traditional laparoscopy such as two- Paris (France) and Leipzig (Germany). DaVinciTM dimensional vision, limited movement of instruments, Surgical System got FDA approval for laparoscopic use in complex reconstruction and difficult suturing and also 2000 and for thoracoscopic use in 2001. Presently, there are surgeon fatigue prompted the introduction and rapid over 220 robotic systems installed worldwide including 12 assimilation of robotic systems. in Asia and 3 in India. 365 Apollo Medicine, Vol. 3, No. 4, December 2006 Review Article Computer Motion introduced its prototype Zeus computer to control and countercheck the performance of Telepresence Surgery System in 1996. This system also the machine. consisted of a camera-positioning arm and two instrument arms operating laparoscopic instruments; similar to Robotic arms (Fig.2), two surgical manipulators and conventional rigid instruments .Currently, computer motion one camera arm. The surgical manipulators drive the is conducting FDA approved clinical trials in laparoscopic, instruments and camera arm holds and moves the telescope thoracoscopic, and cardiac applications. and camera unit. The arms may be mounted on a cart (daVinci) or on the operating table (Zeus). The camera arm THE MAINSTREAM SURGICAL ROBOTS of Zeus is essentially an AESOP robot voice controlled by the surgeon. Two surgical robots are currently available for clinical applications the daVinciTM Surgical System (Intuitive Auxiliary or vision cart, containing light sources, Surgicals, Sunnyvale, CA) and ZeusTM Robotic Surgical camera control units, camera signal synchronizers, and System (Computer Motion, Altlanta, GA). Both the systems monitors for patient side assistants. have some similarities in their designs. They consist of following three basic parts. These systems have incorporated mechanisms to overcome the difficulties encountered by the minimally Surgeon’s console (Fig. 1) is the user interface of invasive surgeons. these robots. It consists of (1) Display system–a 2D or Stereoscopic display system; (2) Master arms or surgeons HAND-EYE COORDINATION handles - the surgeon moves the masters, the movements are In daVinci, the display system projects the image in the translated in real time into movements of instrument tips, direction of the surgeon’s hands via a mirror overlay optical the slaves. The masters also provide a force feedback to the system restoring hand eye coordination. Zeus system has a operating surgeon’s hands. In daVinci the masters can be high definition monitor at the eye level in front of the made to control camera movements by pressing a foot surgeon. paddle. Zeus system incorporates a HermesTM voice control system for camera movements; (3) Control panel–permits DEPTH PERCEPTION surgeon to choose and adjust various display and control options; and (4) CPU or the controller–high capacity DaVinci system has two separate optical channels. The telescope is a combination two 5 mm scopes enclosed side by side in an 11 mm sheath, one scope for each eye’s vision. The camera mounted atop these this telescope has two independent three chip CCDs that delivers pictures with 800 lines of resolution. These images are displayed on two cathode ray tube monitors, each displaying slightly different image to each eye giving a 3D vision with a wide stereo separation. The initial models of Zeus were shipped with 2D display but recent model is 3D capable. Fig. 1. The console Fig. 2. The arms Apollo Medicine, Vol. 3, No. 4, December 2006 366 Review Article INTUITIVE MOVEMENTS The CPU or the controller translates the movements of masters by surgeon in an intuitive way, i.e., movement of master to right is translated to movement of the slave instrument to the right. All the time this is happening, the movements and positions of slaves and masters are being checked and correlated in x, y and z -axis at more than 1000 times per second. The immense processing power of the controller also bring the visual and robotic frame of reference into precise registration giving surgeon a sense of immersion in the work. The force feedback lets surgeon feel large contact interactions and indicates robots workspace limits. The controller also permits the advanced features like clutching (indexing) between masters and slaves, smooth control at workspace limits, and gravity compensation. PRECISION Tremor eliminating algorithms are incorporated in both surgical robots. They filter out the natural hand tremors of the surgeon. The movements can be scaled down from 1 : 1 to 3 : 1, i.e., three-inch movement at the master is translated into one-inch movement at the instrument tip. Tremor filtering and scaling down of movements, coupled with the 12-15 magnification offered by the display systems bring unprecedented precision at the minimally invasive surgeon’s hand. SEVEN DEGREE OF FREEDOM MOVEMENTS DaVinci system’s slave arms with articulated instrument tips (EndowristTM) (Fig. 3) provide seven DOF movements Fig. 3. EndowristTM like human wrist. The slave arms provide outer pitch, outer yaw, roll, and insertion movements, while the articulated However, at least for the time-being, the costs of the device tips provide inner pitch, inner yaw, and grip. The initial Zeus preclude this from being a major reason for its use. systems had nonarticulating tip instruments (micro- assistTM). The recent models have instruments with DISADVANTAGES articulating tips (micro-jointTM). Cost ERGONOMIC DESIGN The device itself costs upwards of INR 5,00,00,000 and The surgeon consoles in both the systems are then requires annual maintenance and disposable ergonomically designed. Operating surgeon does not scrub instruments. This has probably been the biggest hindrance and performs whole surgery while sitting comfortably on to its widespread use but, as with other new technologies,