Uniformed Services University of the Health Sciences
Department of Surgery
4301 Jones Bridge Road
Bethesda, Maryland 20814
Phone: (301) 295-3155
Fax: (301) 295-3627
Eric A. Elster, MD
CAPT, MC, USN
Patricia L. McKay, MD
CAPT, MC, USN
The rapid advancement of today's computer technology has introduced a growing trend in training, particularly in the medical field. In addition to the university's unique military curriculum, simulation technology providing advanced training in several of USU's departments.
The SRI Telepresence Surgery System (TeSS) has quickly gained recognition as an exciting technological training tool at USU. The remote surgery lab, recently relocated to the Department of Laboratory Animal Medicine, is the newest in the group of advanced training tools.
Lt. Col. Christoph R. Kaufmann, MC, USA, Chief of USU's Division of Trauma and Combat Surgery, and Lt. Col. David Burris, MC, USA, an assistant professor in the Department of Surgery, both USU Class of 1982 graduates, have been working with the system since July 1997, when it arrived at the university. Kaufmann and Burris frequently instruct students and outside observers in the use of the system.
The remote surgery laboratory occupies two rooms at the university. One room houses the operator module, which consists of a color monitor, a liquid crystal shutter, used in conjunction with polarized glasses for stereo graphic viewing, a mirror to create a virtual work space beneath the hand-operated master controller, stereo speakers, and surgical instrument handles. The other room is occupied by the remote, or surgical manipulator. The unit is comprised of two color CCD video cameras, approximately 12 cm. apart, the same interocular vision that we experience with a visual field 40 cm. in front of us, a force reflecting manipulator, and two microphones. This set-up allows for interaction between the instructor and the students, and between the surgeon and the patient.
The arms are controlled by small motors attached to each axis by gears, timing belts, and cables. The ends of the arms are equipped with interchangeable surgical instrument tips, providing force feedback which can be adjusted accordingly to represent the sensitivity of particular cases.
Flight simulators, which have been in use for training for more than seven decades, provide a role model for surgical simulators. Due to their advancement over the years, a great deal of research and development have gone into identifying requirements for realistic, reliable training in a simulation environment. With its finite and quantifiable timeline, and procedural dependence, surgery is especially suited for simulation training.
As in flight simulator training, surgical simulation technology will allow for proficiency testing in individuals. With the requirement for high levels of realism and sophisticated visual, audio and motion-based systems, the simulators can be used to rehearse, train and develop new procedures.
The TeSS has two clear uses, patient care, both local and remote, and surgical education. Several current techniques, including laparoscopy and endoscopy, already place the physician at a distance from the operative area, using scopes, catheters, and video monitors for remote manipulation of surgical instruments. This paves the way for an easier transition from traditional methods to the simulation environment.
The use of the remote system in local procedures removes some of the natural anatomical barriers traditionally experienced by surgeons. In the future, specific anatomic features will be able to be rendered electronically 'off limits," decreasing the risk to the patient. Certain motions, such as a heartbeat, can appear to cease with synchronization of instrument motion, and microsurgery can be facilitated.
Remote use of the system introduces greater limitations. Although the system is intended for future use in remote locations and battlefield scenarios, the high information flow rate required to properly operate the Pentium-based system across distances makes it impractical for battlefield use today. To perform real-time surgery, the system requires a huge transmission band width, even more than the Tl access USU has to the internet.
Currently, the system is being used primarily for surgical education at USU. Some third-year medical students are introduced to the system as part of the surgical skills course curriculum. The students perform as a surgical team in a "remote' environment. USU students are now receiving training in several simulation labs. Third-year students work with the remote surgery system during surgical skills rotations, the anesthesia patient simulator during their anesthesia rotations, and all fourth-year students now receive training in telemedicine at Operation Bushmaster, the field training exercise held at Camp Bullis, Texas.
In both the remote surgery and the anesthesia simulator, USU is acting as a test bed. The primary operators determine the positive and negative aspects of the system, record procedural problems and deficiencies and report them to the manufacturer. Results of various procedures, real-time measurements, and tool functionality are being plotted, and stored for subsequent analysis. Feedback from the users working with the prototype equipment will allow for improvement of future models. Simulation training provides a safe environment where students can rehearse and train in unique scenarios, without endangering themselves or patients. It also provides an alternative to ethical issues commonly involved in training.
The remote surgery project is attracting outside interest, as well as providing USU students another aspect of advanced training not available at other medical schools. The laboratory has received an overwhelming amount of media interest, on a regional, national and international level.
Kaufmann compares TeSS to the Wright Brothers first plane. Although it isn't ideally functional, it works well, and has great potential. With the rapid advancement in computer sciences, the advanced capabilities required to operate in a remote location are highly feasible. Although it may be 10 to 20 years before we see the use of remote surgery on the battlefield, we can expect to see its impact in the operating room very soon.