Multiple Training Systems Under Study at the University of Nebraska

by John Otrompke

Follow-up research is underway to validate a surgical training module used in-house at the University of Nebraska. The training method has already demonstrated improvements in speed and smoothness of movement, according to a paper recently published in the International Journal of Medical Robotics and Computer-Assisted Surgery.

Following the most recent publication, researchers are validating the results with a larger trial.  “Right now we’re in the middle of about 25 subjects, and hopefully we’ll get about 50 students students and fellows,” said Dr. Joseph Ka-Chun Siu, PhD, assistant professor in the College of Public Health. The current study will look at retention of skills six months following training, he said.

The training program, which is in its fifth year, has trained about 30 individuals in da Vinci surgery, using an interface provided by Intuitive and a custom LabView program manufactured by National Instruments out of Concord, Massachusetts.

The training program uses a technique called Augman video feedback, in which participants can either watch their performance in real time or obtain quantitative measures of fast they perform surgical procedures such as suturing, Siu said. The institution purchased the commercial LabView software about ten years ago for about $1,000, according to Siu, and subsequently customized the software, because “the robot has no direct communication back to the surgeon, saying how well you do in this procedure,” Siu explained.

        Improvement in Some Measures, While Others Remain Enigmatic

   In the training program, 15 medical students with no prior robotic surgery experience went through a four-day training program followed by a retention test a day later, according to the article (“,Training program for fundamental surgical skill in robotic laparoscopic surgery,” Suh, Mukherjee, Oleynikov and Siu). 

Prior to the retention test, the average score measured by the Objective standardized assessment of technical skills (OSATS) criteria was 43.1%, but it increased to 66.4% after the training, and 74.1% at the time the retention test was administered, the paper said. 

The students averaged 25 years; 12 were male,  and three female. Researchers also examined the activities of the flexor carpi radialis and extensor digitorum, two muscles in the forearm that have been associated with surgical fatigue, and found that fatigue was reduced following the training program.

“We’re not going to strengthen the muscles, but rather to see how much muscle effort they use in order to complete the task,” explained Siu, who noted that the paper reported about a 30% reduction in fatigue following the training program.

Researchers found the simulator improved a measure called ‘movement curvature,’ a measure of “whether you move the robot in a smooth fashion,” according to Siu.

All students were right-handed. There were no significant differences in terms of the total distance traveled in performing the surgical procedures studied, the paper said. A prior randomized study of ten volunteers (“A Virtual Reality Training Program for Improvement of Robotic Surgical Skills,” Mukherjee, Siu, et al, Studies in Health Technology and Informatics, 2009), found that improvements in total distance traveled enjoyed by students who used a virtual reality simulator disappeared when students used their non-dominant arm. However, that study involved a virtual reality program, not the LabView module, according to Siu.

                         Bountiful Training Modules

Another early study from 2008 (“Validated robotic laparoscopic surgical training in a virtual-reality environment,” Katsavelis, Siu, et al, Surgical Endoscopy, 2008), noted the desirability of increasing the complexity of the virtual reality training environment.

“To increase the complexity of the tasks, we are increasing the steps for the participant to complete. That first report involved very simple tasks like bimanual carrying and needle passing, but right now we use the mesh alignment task, a procedure that people commonly use to repair a hernia, which requires multiple steps in order to complete,” Siu explained.

Another change from the earlier papers is that the virtual reality training program now uses a program called Vizart, manufactured by Worldviz, instead of the Webots program used initially.

“Worldlviz gives us more degrees of freedom, because the virtual object is written in a simple language, so that we can write it by ourself. Provide syntax so we can modify it with drop-down menus,” Siu said.

Regarding the module used in the training program, which incorporates the Labview product, but not the virtual reality simulator, Siu said the institution has not yet sold the product to anybody, although the studies have shown that 80 to 90% of participants improve their surgical skills. “We just use that one as our in-house training program. We did not have a good communication with the company” regarding commercialization, because Intuitive still has ownership of the platform, he explained.

Accordingly, the institution is also developing its own training simulator, which does not use the LabView product, he said.