Computer-assisted robotic surgery and telesurgery

Table of Contents

The Foundation of Computer-assisted Robotic Surgery
Invasive and Minimally Invasive Surgery

Components of a Surgical System
Surgeon’s Console
Patient-side Cart and Image-Processing and Insufflations Stack

Advantages of Computer-assisted Robotic Surgery
Surgeons Advantages
EndoWrist
Motion Scaling
Three-Dimensional Imaging
Morbidly Obese Patients

Disadvantages of Computer-assisted Robotic Surgery
Institutional
Patient
S urgeon
OR Staff

Telemedicine and Telesurgery

Technical Issues with Telesurgery
Technical Issues Defined

Technical and Legal Issues with Telesurgery
Malpractice and Connectivity
Dealing with Technical Issues

First Telesurgery Procedure

Robot-assisted Cholecystectomy
Patients & Methods
Results
Discussion

Long-Term Follow-up After Robotic Cholecystectomy
Patients & Methods
Results
Discussion

Telesurgery as an Educational Tool
Educating the Student

Recent Advances and Future Applications of Robotics in Health Care
The Penelope
Robotic Rounds

Future Applications of Computer-assisted Robotics in Telesurgery

Conclusion

Figures and Tables

Length of Stay

Pre-Operation Symptoms

Post-Operation Symptoms

Executive Summary

The purpose of this report is to explore and describe the innovation of computer-assisted robotics in minimally invasive surgery and in telesurgery.

The scope of this report includes the following topics: the advantages and disadvantages of computer-assisted surgery, the explanation of telemedicine and telesurgery, the technical issues of telesurgery, the description of the first remote telesurgery procedure, two case studies involving computer-assisted surgery, telesurgery as an educational tool, the applications of remote telesurgery, remote telesurgery limitations, and the future of telemedicine and telesurgery.

Computer-Assisted Robotic Surgery and Telesurgery

Tyson H. Lantz

University of Nebraska at Omaha

The Latin phrase Primum non nocere, which translates to “First, do no harm”, is a common ethical lesson taught to medical students, and it is a fundamental principle to be followed in practicing medicine. The importance of this statement becomes even more emphatic when one considers that the practice of medicine today is becoming continually more reliant on technology to aid in the diagnosis and treatment of diseases and conditions. Technology is an everyday aspect of people’s daily lives, and their lives continue to be improved with computers and technological advancement. For example, the use of technology, specifically computers, has been in use in the medical setting for fifty years, however, within the last twenty years, computers have started to make their way into the operating room at an ever increasing rate. As a result of this increased use in the operating room, computers are becoming highly valuable and crucial members of the surgical team.

By combining clinical decision support systems with patient-specific data, physicians now have the ability to use intelligent devices and technologies to create a perioperative zone of safety for patients. Intuitive Surgical (2012), a computer-assisted robotic surgical system developer and manufacturer, explains that the daVinci Surgical System has the capabilities necessary to “perform delicate and complex operations through a few tiny incisions with increased vision, precision, and dexterity and control”. This translates into decreased blood loss, reduced tissue trauma, reduction in length of stay at the hospital, and increased postoperative recovery for the patient. Furthermore, in situations where the surgeon and patient are physically in different locations, some surgical systems can be used by the surgeon to perform surgery on the patient, using an innovative approach known as telesurgery. This is the future of medicine as people know it, and the following presents an in depth investigation and discussion into what is now becoming a standard of practice in the operative setting.

The Foundation of Computer-assisted Robotic Surgery

Modern surgery has come a long way from bloodletting, the practice of draining a person’s blood to cure an ailment, dating as far back as the fifth century BC (Sharp, 2001). Previous to surgery with robots, years of education and development of surgical practice and technique was needed. As a result of this development of surgical practice and technique, tremendous benefits have been yielded for those people requiring surgery. In short, the realm of surgery has evolved from that which is known as invasive surgery to that which is known as laparscopic surgery, also referred to as minimally invasive surgery. Computer-assisted robotic surgery takes minimally invasive surgery and builds upon the concept.

Invasive and Minimally Invasive Surgery

Before laparoscopic and computer-assisted robotic surgery, invasive surgery involved a large incision, also referred to as an “open” procedure or laparotomy, where the entire cavity of the patient was exposed for the surgeon. In comparison, the premise behind laparoscopic surgery or minimally invasive surgery is to access the body cavity through multiple tiny incisions, usually no bigger than a half-inch in diameter. Ports, also known as trocars, are placed into these small incisions, producing channels to allow access to the inside of the patient. These channels provide a way for longer instruments to be introduced and used in the body. Additionally, a small camera, known as a laparoscopic camera, is placed through one of the ports. It is used to transmit an image onto a television monitor for the surgeon and assistants to view. In this manner, the laparoscopic camera becomes the surgeon’s eyes because the surgeon is not able to see directly into the patient without the traditional large incision.

Components of a Surgical System

As stated previously, computer-assisted robotic surgery takes laparoscopic or minimally invasive surgery and builds upon the concept. During computer-assisted robotic surgery, the surgeon is able to expand the capabilities within the operative field while doing so in an even less invasive way than traditional laparoscopic surgery. Satava explains the concept of a surgical system by stating that it “is not a machine, it is an information system with arms” (2005). In essence, “by using the robot, the surgeon looks at the video image (the electronic representation of the organs) and moves the handles which send electronic signals (information) to the tips of the instruments – surgery becomes a flow of information” (Satava, 2005). One such robotic surgical system, the daVinci, is composed of three components which are the surgeon’s console, the patient-side cart, and the image-processing and insufflations stack. The following is a brief discussion of each of these components.

Surgeon’s Console

Once again, a surgical system is not a machine, and it is not artificially intelligent, i.e., it does not have a mind of its own. Therefore, a surgical system needs the control of a surgeon to perform any duties; hence, it is a master-slave unit. The surgeon’s console (master unit) is placed within the surgical suite but away from the operating table. A three-dimensional image from the stereoscopic endoscope, which is an instrument inserted into an internal organ of the body cavity to allow viewing of its interior, is projected into the console, magnified at ten times the normal viewing capabilities of the human eye for precise viewing of the operative site (Murphy et al., 2008). The placement of the surgeon’s thumb and forefinger at the telemanipulators (controls) in the surgeon’s console and subsequent movements of the telemanipulators are then transferred to movements of the robotic ‘arms’. The foot controls at the surgeon’s console provide power to a diathermy, which is used to aid in the cutting and cauterization of tissue, as well as to control other energy sources used in surgery.

Patient-side Cart and Image-Processing and Insufflations Stack

The robotic ‘arms’ are located on the patient-side cart (slave unit) which is placed at the operating table. The patient-side cart has the capability of providing up to four robotic ‘arms’, all of which can hold a high-resolution three-dimensional stereoscopic endoscope, instrument or retractor, a device used to separate an incision or wound or to hold tissue in place. The final piece of equipment is the image-processing and insufflations stack which contains the camera-control unit for three-dimensional image processing, an image-recording device, a laparoscopic insufflator used to blow air or gas into a body cavity, and a monitor with two-dimensional viewing for assistants.

Advantages of Computer-assisted Robotic Surgery

Computer-assisted robotic surgery offers multiple benefits over traditional invasive and laparoscopic surgery. These advantages include those specific to the surgeon such as increased wrist dexterity, motion control, and vision. Computer-assisted robotic surgery also allows for the use of sturdier instrumentation better suited to laparoscopic surgery in morbidly obese patients. In addition, the daVinci surgical system has the ability to “import the patient’s holomer and the surgeon can perform preoperative planning, surgical rehearsal or even surgical simulation for training and assessment” (Satava, 2005). Explained by VirtualSoldier.us, “The holomer (HOLO -graphic M -edical E -lectronic R -epresentation) is a three dimensional holographic digital image of a specific person” (2012). Physicians have the ability “to interact with the holomer as if it were the patients themselves” (VirutalSoldier.us, 2012).

Surgeon’s Advantages

EndoWrist.

Computer-assisted robotic surgery has numerous advantages over traditional laparoscopic surgery. During computer-assisted robotic surgery, the surgeon is able to expand the capabilities within the operative field while doing so in a less invasive way than traditional laparoscopic surgery. Traditional laparoscopic instruments only offer surgeons four degrees of freedom, while the EndoWrist, which is available on the daVinci computer-assisted robotic surgical system, offers seven degrees of freedom (Murphy, Hall, Rong, Goel, Costello, 2008; Intuitive Surgical, 2012). EndoWrist instruments offer the surgeon natural dexterity, along with providing even greater range of motion that is naturally exhibited by human wrist articulations much like open surgery (Intuitive Surgical, 2012). Unlike traditional laparoscopic instruments, Intuitive Surgical explains that the internal cables of EndoWrist instruments offer maximum responsiveness, allowing rapid and precise suturing, dissection and tissue manipulation (2012). Traditional laparoscopic instruments have a ‘fulcrum’ effect, which occurs when the tip of the instrument’s movements are opposite the direction of the surgeon’s hand movements. The ‘intuitive’ nature of computer-assisted robotic surgery cancels this effect, allowing the instruments to move in the precise direction of the surgeon’s hand movements in the surgeon’s console (Murphy et al., 2008).

Motion Scaling.

Dr. Ayal M. Kaynan explains, “In standard laparoscopy, distance of the tissue structure from the port site on the abdomen causes amplification of motion at the instrument tip” (2009). The slightest motion outside of the patient can translate into a relatively large motion inside the operative field. Motions can be scaled up to a five to one ratio by filtering and de-amplifying the surgeon’s hand movements at the console. In doing so, the surgeon must move the manipulators at the console five inches for the tip of the instrument to move one inch. As stated by Dr. Ayal M. Kaynan, “This eliminates natural hand tremor entirely, allows the surgeon to target tissues with much greater ease, and gives the surgeon a certain finesse that surpasses human capabilities in both the open and standard laparoscopic realms” (2009). In addition, the daVinci Surgical System uses a motion filter to isolate the frequency at which hand tremors occur, “eliminating unintended movements caused by human tremor” (Hirano, Ishikawa, Watanabe, 2010).

Three-Dimensional Imaging.

With conventional laparoscopes, the image viewed by the surgeon and assistants are limited to two-dimensional vision. The daVinci robotic laparoscope is actually comprised of two separate lenses that are used in conjunction to give the perspective of a three-dimensional image which mimics natural vision and gives true precision depth (Kaynan, 2009; Intuitive Surgical, 2012). The high-resolution three-dimensional stereoscopic vision allows the surgeon to target tissues properly by not having to make inferences about spatial relations, which typically happens with the traditional two-dimensional image provided by a standard laparoscope. Many times a surgeon will make small test movements to either confirm or refute the inferences made about spatial relationships; the daVinci robot all but eliminates the need to make test movements.

Morbidly Obese Patients

In the morbidly obese, traditional laparoscopic instruments tend to bend. This problem is due to the increased pressure loads that must be exerted on the instruments by the surgeon. Precise operative technique becomes even more difficult with patients of a body mass index (BMI) greater than 60 kg/m^2 because of the added torque that must be exerted on the instruments (Jacobsen, Berger, Horgan, 2003). This dilemma is alleviated by the use of instrumentation which is more rigid and created for such situations. As explained by Jacobsen et al., “the stiffer instrumentation eliminates bending of the instruments, and the mechanical power provided by the robot eliminates surgeon fatigue and allows a coordinated, precise manipulation of tissues” (2003).

Disadvantages of Computer-assisted Surgery

As previously described, computer-assisted robotic surgery offers a multitude of benefits over traditional invasive and laparoscopic surgery. However, it does not come without some disadvantages or drawbacks. These include those specific to the institution, patient, and surgeon as well as the operating room staff. Among these are cost, possible suture failure, physician learning curve, and setup time in preparing the robot for surgery. While none of these are potentially life-threatening, they all pose areas of concern which can be weighed as possible drawbacks of computer-assisted robotic surgery.

Institutional

Even though computer-assisted robotic surgery offers numerous benefits, there are some drawbacks that are related to the physical system as well as disadvantages encountered during operation. Hospitals can easily be deterred by the implementation, operating, maintenance and training costs associated with computer-assisted robotic surgery. While many health care facilities are not equipped financially to incur the large costs associated with the use of computer-assisted robotic surgery, there are over 1,840 daVinci Systems installed in over 1,450 hospitals worldwide (Intuitive Surgical, 2012). Data put together by Diana Gehardus show that initial costs for the daVinci Surgical System are in the neighborhood of one million dollars, with an annual maintenance cost of one-hundred thousand dollars and physician training running a quarter of a million (as cited in Computer Motion, Inc., 2002; Intuitive Surgical, Inc., 2002; Value and Feasibility, 2002). Gehardus also states each surgical instrument for the daVinci must be replaced after ten cases (procedures), at a price of two thousand dollars per instrument (as cited in Stark, 2002).

Patient

In addition to the costs associated with the daVinci System, another drawback is in the area of possible suture failure. When transitioning from open surgery, as well as laparoscopic surgery to computer-assisted robotic surgery, the biggest difference that a surgeon will incur is no tactile feedback to movement of the telemanipulators. Evidence suggests, as reported by Hirano et al., “Some studies have shown that the higher risk of breaking sutures when using the robot can be attributed to the absence of tactile feedback in the robotic system” (2010). If the surgeon does not break the suture, lack of tactile feedback could also lead to the stressing of the tensile strength of the suture, potentially leading to premature failure. Thus, surgeons are even more reliant on the three-dimensional picture provided by the high definition camera when suturing. It has also been noticed that if proper care is not taken to monitor the position and tension of retraction devices that are held in a fixed position by the robot, the potential for unintended tissue trauma can occur (Newlin, Maikami, Melvin, 2004). It should be noted that although daVinci Surgical Systems at this time does not offer tactile feedback with their system, Surgeon’s Operating Force-feedback Interface Eindhoven, or Sofie and NeuroArm provide tactile feedback on their computer-assisted robotic surgical systems (Coxworth, 2010; Hawaleshka, 2002).

Surgeon

As stated previously, costs incurred by a health care facility to train physicians to use the da Vinci System totaled a quarter of a million dollars, however, training also presents other challenges in addition to the financial challenge. As one might expect, there is a learning curve associated with adjusting to the surgeon console, which includes the three-dimensional screens for viewing, telemanipulators and foot controls. Training centers are located throughout different locations within the United States, where training involves picking up objects with robotic arms by maneuvering the telemanipulators, as well as operating on human and animal cadavers among other exercises (Gehardus, 2003). Rigorous training of up to and over forty hours is required for the physician to even be considered familiar with the operation of the computer-assisted robot. Gehardus also states that “the surgeon may need to operate on 12 to 18 patients using the technology before he or she can feel comfortable and can perform the operation within standard times” (as cited in Meadows 2002).

Operating Room Staff

With the addition of new and unfamiliar technology into the operating room, sterile surgical team members as well as non-sterile surgical team members initially incur lengthy setup times associated with preparing the robot for a procedure. For example, at the University of Illinois, initial setup time on the daVinci robot for a Roux-en-Y gastric bypass procedure was thirty-five minutes (Jacobsen et al., 2003). However, Joacobsen et al., went on to say that after two hundred cases with the daVinci Surgical System, team members became so proficient at preparing the robot, seven minutes became the average time added onto each case (2003). Also, at the New York Medical College, surgeons reported similar times associated with the setup of the robot, with a six to eight minute window becoming the average setup time (Jacobsen et al., 2003). Nevertheless, the learning curve associated with the operating staff to become efficient in preparing the robot for a procedure is definitely a disadvantage of computer-assisted robotic surgery.