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Robotic Surgery

A NextGen Free-Standing Perspectives Article

The burgeoning usage of the term "Robotic Surgery" in not just among medical professionals, but also in laymen vernacular indicates an increased popularity of conducting surgeries with the aid of robots. There are over 300 sites in the country that are currently using the 'da Vinci Surgical System', a teleoperative machine designed by the company Intuitive Surgical of Sunnyvale, CA., for areas such as cardiac, urologic, gynecologic and general surgery (1). So far, Intuitive Surgical has dominated this market, including acquiring their primary competitor (Computer Motion) in June of 2003 (2). Though, companies such as Hansen Medical, Intergrated Surgical Systems Inc., and others are also producing innovative technologies for the field of robotic surgery. The use of these computer-aided tools has grown from 1500 cases in the year 2000, to an estimated 20,000 cases in 2004 (3), suggesting that robotic assisted surgery is becoming more widely accepted as a practical application in the medical field. The trend also poses new questions in the advantages of the technology, in the training of medical students and current physicians, in the development of the medical robotics market, and in the future expectations for the field of surgery.

The idea of telesurgery was principally developed by the military with the intentions of allowing surgeons to treat wounded soldiers miles away, all the while being removed from the dangers and uncertainties of the battlefield. While this capability is still theoretically possible, today, the emphasis placed by Intuitive Surgical and the physicians using the technology has shifted. In a more commercial sense, telerobotics is where the surgeon sits in a remote area (distance varies) from the operating table, and assumes control of the robot's motion. The surgeon uses master control handles that receive force feedback, along with a 3D stereoscopic visual display to direct the instruments entering the patient's body. The robot cannot make decisions, nor can it perform any type of movement or maneuver without the surgeon's direct input. Thus, the robot has virtually no level of autonomy.

Dr. Moritz Ziegler, Surgeon-in-Chief at The Children's Hospital in Denver, CO., states that the robot has added advantages, because "mechanically, you can make a device that has more degrees of freedom in the movement of the mechanical arm than the human wrist. Any kind of tremor factor, which all surgeons have to one degree or another, is totally eliminated by the mechanical device so that the precision of placing a stitch, or doing a maneuver in an operation can be better defined." Degrees of freedom refer to the number of independent movements an object or 'entity' can make. Six degrees of freedom are required to reach, position, and orient an instrument at any point in space. The seventh degree of freedom is the function of the operation itself (e.g., grasping or cutting) (4). The da Vinci Surgical System's instruments subsume all seven degrees of freedom; this is in contrast to the human wrist, which is only capable of 4 degrees of freedom while using a laparoscopic instrument. Essentially, these characteristics of the robot, along with the 3D visual display, provide the surgeon with an increased capability that allows him or her to perform minimally invasive surgery more precisely.

Minimally invasive surgery, (also known as MIS, minimal access, keyhole surgery, laparoscopic, or endoscopic surgery), is performed by making 1–3cm incisions, and using pencil-sized instruments that are passed through natural body cavities and incisions. This is in contrast to traditional surgical protocols where surgeons begin with a single, long incision (usually 6–12 inches), and visualize the site of interest by opening wide the body cavities. Laparoscopic surgery takes advantage of endoscopy (the insertion of cameras into the body cavity), to help the surgeon visualize the inside of the body without a need for long incisions. Smaller incisions mean less blood-loss, pain, or likelihood for infections; and further more reduces the recovery time from the surgery, such that MIS can increase the rate of successful surgeries.

It is important to note that minimal access surgery can be performed without the use of robots, and that in certain procedures, these computer-aided tools show no apparent advantage. Dr. Thomas Krummel, Professor and Chair of Surgery at Stanford Medical School, explains that robotic surgery is just "another tool that has specific applications. Patients undergoing an appendectomy show very little differences between the robot and the traditional method—relating to a low need. In contrast, procedures done on the prostate have shown significant outcomes with the robot and would therefore have a high need for this technology." Specifically in prostatectomy cases, robotic technology has allowed surgeons to make a series of smaller incisions instead of one large incision, permitting patients to better avoid post-surgical infections, and to achieve a lower risk of impotency and incontinence.

The benefits of robotic surgery, however, can carry a hefty price tag. The initial cost of each da Vinci Surgical System is 1.5 million dollars, with annual upkeeps costing approximately $100,000. On average, the use of robotic technology increases the surgical costs in increments of thousands of dollars, where the increase in cost is relative to both the complexity of the procedure and risk associated with that surgery. However, many would argue that the need for less medication and a shorter hospital stay offsets the total expenditure for the patient. This is why robotic technology is looking for an application rather then a need. Dr. Ziegler believes that due to high expenses associated with the procedures using these computer-aided tools, health institutions must clearly demonstrate the advantage of this technology on the outcomes of the procedures. Individuals and insurance companies will be less likely to pay for procedures using the robotic system if they can be performed just as well through alternative methods.

Patients are not the only ones who may benefit from robotic technology, surgeons benefit as well. Dr. Sanjeev Dutta, Director of Stanford's Surgical Skills Curriculum, believes that the robot is "an enabling technology. This is important because, as robotic technologies improve and become more user-friendly, more surgeons are likely to attempt minimal access operations that they otherwise would not have tried because of their lack of laparoscopic skill." For an experienced surgeon, it would be a matter of months to become completely competent in robotic surgery. A doctor's overall understanding of operation procedures and the ability of their surgical team contribute to the rate at which they may become proficient in robotic assisted surgery.

For medical students, robotic surgery and other new technologies are unlikely to affect their training in their first four years. The technologies will, however, influence postgraduate surgical training. After individuals finish their general surgical residency, they will be able to participate in a fellowship in advanced laparoscopic surgery that lasts approximately two years. The robotic surgery training in residency begins with manuals, observation of robotic surgeries, and simulators at a training center. After the novice surgeons have had extensive background information, they begin training with the robot itself through a progressive stage of exercises. Initial training requires the students to suture a piece of foam or rubber. Once proficiency is established at each stage, the trainees will be presented with more demanding tasks such as "operating" on cadavers. After continually refining their knowledge and technique the trainees will graduate from the fellowship as skillful surgeons in the art of robotic surgery.

There are many different opinions regarding the future of this technology, though one thing remains certain, and that is robotic surgery is here to stay. Dr. Dutta speculates that in the next 15–20 years the robot "will look entirely different and will reduce in size and become more user-friendly, probably more modular." We can expect to discover more useful applications of the technology. Eventually, these computer-aided tools will become the norm for specific applications, especially those requiring very small incisions on small organs. Medical students and surgical trainees may not have to choose to study robotic surgery—it may someday be a standard technique.

Along with its rise in popularity, it will be pertinent to watch for the possibility of abuse, ultimately translating to issues of patient safety. Some may attempt to use the technology to attract business while neglecting to properly train in the use of surgical robots. Strict regulation of the sale and use of these devices will be required to ensure patient safety.

Robotic assisted surgery is an exciting new field. At the end of the day, however, one must understand that these surgical systems are just tools. They are instruments that enable the surgeon to perform minimally invasive surgery easier and are applied to specific applications where the patient's outcome is benefited. The key is to assess the situation to allow the right surgeon to use the right tools on the right patients. 

Matt Guidarelli is a contributing writer for the Next Generation and a member of the Colorado State University Class of 2008.

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Cited Works

1. Intuitive Surgical. Company Page, 2005. Accessed March 5, 2006. <http://www.intuitivesurgical.com/ corporate/index.aspx> (Text)
2. Intuitive Surgical. Da Vinci Surgical System FAQ, 2005. Accessed April 19, 2006. <http://www. intuitivesurgical.com/corporate/newsroom/mediakit/index.aspx> (Text)
3. Cropper, Carol Marie. "The Robot is in — and Ready to Operate." Business Week. March 14, 2005. (Text)
4. Intuitive Surgical. Glossary, 2005. Accessed March 5, 2006. <http://www. intuitivesurgical.com/patientresources/glossary/index.aspx> (Text)

Physicians Interviewed

1. Dutta, Dr. Sanjeev. "Re: Answers to your questions." Email to the author. March 26, 2006
2. Krummel, Dr. Thomas. Phone interview. March 24, 2006
3. Ziegler, Dr. Moritz. Personal interview. February 17, 2006

Multimedia Used
Images of surgery and MIS surgery provided and copyright 2006 by Intuitive Surgical.

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