The first internet-based remote-controlled surgical robot was demonstrated in South Korea last month. Professor Kim Yoon-hyuk from Kyung Hee University's College of Advanced Technology and Professors Rha Koon-ho and Hyung Woo-jin from Yonsei University College of Medicine's Robot Surgery Center built the robot, called Kyung Hee SR1.
The robot was built with a grant of US$167,000 from the Korea Food and Drug Administration. The system consists of two robotic arms that measure 90 centimeters across and weigh 70 kilograms. The machine can be connected to the Internet and receive instructions from any doctor in the entire world.
The demonstration on October 10 involved Professor Rah operating remotely on pig intestines that were placed in a mannequin. The robot precisely followed his every move.
"Currently a US-made robotic surgical system called da Vinci is dominating the Korean market and the global market. But Kyung Hee SR1 is on par with da Vinci in terms of precision movement," said Prof. Rah.
There is one improvement over the da Vinci system. The Kyung Hee SR1 provides touch feedback so that the operator can feel the force of the robot's grip.
"The Korean robotic surgical system can be commercialized within three years when devices attached to it to help the surgery, such as the endoscope, are developed and clinically tested," Prof. Kim said. "The home-grown system costs from one fifth to one third the price of da Vinci, which amounts to about 2.5 billion won [US$2.8 million]. Hopefully the domestic system will relieve the cost burden from patients."
Surgical robots are a hot research topic all over the world these days. For instance, Italian researchers are testing a robot that can perform liver and kidney surgeries with a very minimal amount of blood loss.
Achille Lucio Gaspari of Rome's Tor Vergata University said the robot, called Altair, uses low-frequency electrical current to raise the temperature in the organs so that blood solidifies, allowing surgeons to make incisions without breaking blood vessels, the Italian news agency ANSA recently reported.
"The machine is like a comb whose teeth are like tiny needles, spreading heat and coagulating the blood," Gaspari told the news service. The robot has been successfully used on 14 liver patients so far.
The leader in robotics surgery, however, is still the da Vinci Surgical System. With already over 210 devices in use throughout the United States, Europe, and Japan, Intuitive Surgical is the leading company in the field of digital surgery.
Approved in July 2000 to perform advanced surgical techniques such as cutting and suturing, this system is the first operative surgical robotic system to be cleared by the FDA, giving it a firstmover advantage over its competitors. Though Intuitive Surgical has had to overcome many obstacles in order to dominate the digital surgery field, it is now a multimillion- dollar business that continues to grow.
Making a one-centimeter keyhole incision to perform the operation, the surgeon is able to engage in minimally invasive surgery through this system. According to Ben Gong, Intuitive Surgical's vice president of finance, da Vinci reduces the average 2-3% infection probability to nearly zero. There are four main components to da Vinci: the surgeon console, patient-side cart, EndoWrist Instruments, and Insite Vision System with high resolution 3D Endoscope and Image Processing Equipment.
The surgeon is situated at a console several feet away from the patient operating table. The surgeon has his head tilted forward and his hands inside the system's master interface. The surgeon sits viewing a magnified three- dimensional image of the surgical field with a real-time progression of the instruments as he operates. The instrument controls enable the surgeon to move within a one cubic foot area of workspace.
The patient-side cart contains the robotic arms that directly contact the patient. It consists of two or three instrument arms and one endoscope arm. The feedback as of today is limited to sensing tool-on-tool collision, so the surgeon needs to rely almost solely on the visual field when suturing or contacting soft tissue. As of 2003, Intuitive launched a fourth arm, costing US$175,000, as a part of a new system installation or as an upgrade to an existing unit. It provides the advantages of being able to manipulate another instrument for complex procedures and removes the need for one operating room nurse.
Detachable instruments allow the robotic arms to maneuver in ways that simulate fine human movements. Each instrument has its own function from suturing to clamping, and is switched from one to the other using quick-release levers on each robotic arm. The device memorizes the position of the robotic arm before the instrument is replaced so that the second one can be reset to the exact same position as the first. The instruments' abilities to rotate in full circles provide an advantage over non-robotic arms. The seven degrees of freedom (meaning the number of independent movements the robot can perform) offers considerable choice in rotation and pivoting.
Moreover, the surgeon is also able to control the amount of force applied, which varies from a fraction of an ounce to several pounds. The Intuitive Masters technology also has the ability to filter out hand tremors and scale movements. As a result, the surgeon's large hand movements can be translated into smaller ones by the robotic device. Carbon dioxide is usually pumped into the body cavity to make more room for the robotic arms to maneuver.
The camera unit or endoscope arm provides enhanced three-dimensional images. This high-resolution real-time magnification showing the inside the patient allows the surgeon to have a considerable advantage over regular surgery. The system provides over a thousand frames of the instrument position per second and filters each image through a video processor that eliminates background noise. The endoscope is programmed to regulate the temperature of the endoscope tip automatically to prevent fogging during the operation3. Unlike The Navigator Control, it also enables the surgeon to quickly switch views through the use of a simple foot pedal.
Robotics advantages and disadvantages
The da Vinci Surgical System reduces hospital stays by about half, reducing hospital cost by about 33%. These fewer days in the intensive care unit are a result of less pain and quicker recovery. Though the size of the device is still not small enough for heart procedures in children, the minimally invasive nature of da Vinci does not leave a large surgical scar and still has some limited applications in children for the time being. Moreover, according to Intuitive Surgical, only 80,000 out of 230,000 new cases of prostate cancer undergo surgery because of the high risk invasive surgery carries, implying that more people may undergo surgery with this evolving technology.
The main drawbacks to this technology are the steep learning curve and high cost of the device. Though Intuitive Surgical does provide a training program, it took surgeons about 12-18 patients before they felt comfortable performing the procedure. One of the greatest challenges facing surgeons who were training on this device was that they felt hindered by the loss of tactile, or haptic, sensation. The large floor-mounted patient-side cart limits the assistant surgeon's access to the patient. However, there are also many who are unable to access the da Vinci based on the steep price. In a paper published by The American Journal of Surgery, 75% of surgeons claimed that they felt financially limited by any system that cost more than US$500,000. As of now, surgery with the da Vinci Surgical System takes 40-50 minutes longer, but the FDA considered this a learning curve variable and expects time to improve with more use of the system.