Training and Assessment of Psychomotor Skills for Performing Laparoscopic Surgery Using BEST-IRIS Virtual Reality Training Simulator

Ramesh MAKAM, D.N.B.; CS Rajan, M.S.; Tulip BRENDON, M.S.;
Shreedhar V, D.N.B.; Saleem K, D.N.B.
Bangalore Endoscopic Surgery Training Institute and Research Centre, A V Hospital
Patalamma Temple Street, Basavanagudi, Bangalore, India – 560 004
E-mail: drramesh@hotmail.com

Sangeeta SHRIVASTAVA; R Sudarshan; CRJ Prakash NAIDU Ph.D.
Institute for Robotics and Intelligent Systems/ Centre for Artificial Intelligence and Robotics
Rajbhavan Circle, High Grounds, Bangalore, India – 560 001
E-mail: naidu@cair.res.in

Abstract: In this article, we present the results of a pilot study that examined the performance of people training on a Virtual Reality based BEST-IRIS Laparoscopic Surgery Training Simulator. The performance of experienced surgeons was examined and compared to the performance of residents. The purpose of this study is to validate the BEST-IRIS training simulator. It appeared to be a useful training and assessment tool.

1. Introduction
The advantages offered by Minimal Invasive Surgery (MIS) in terms of decreased morbidity, early return to work and better cosmoses have seen a rapid adaptation of this by surgeons.

Figure 1: BEST-IRIS Laparoscopic Surgery Training Simulator


But the technical difficulties faced in performing these surgeries in terms of 2D vision, paradoxical movements, hand-eye co-ordination and use of new instrumentation and techniques has increased the complications during surgery. Hence there is a need for improved training devices for precise training and assessment of surgical skills in MIS. A virtual reality simulator (Figure 1) was developed by BEST and IRIS to train and evaluate psychomotor skills for laparoscopic surgery.
The different kinds of surgeries performed by Gastro Intestinal surgeons, gynecologists, urologists, pediatric and endocrine surgeons were recorded and the various actions performed during the surgeries were analyzed. The basic actions performed were noted and exercises were designed to mimic these basic actions. Any surgery would be a permutation and combination of these basic exercises. This system is highly user friendly and cost effective. It is a PC based (works on PII) simulator. Highly experienced laparoscopic surgeons have designed the exercises. The tasks in these exercises translate realistically to laparoscopic surgeries. Figure 2 shows an exercise which abstracts ovarian cyst drilling. Different levels of difficulty provided in each exercise cater to training of the surgeon both in basic and advanced laparoscopy.
 

Figure 2: One of the exercises of the simulator	Figure 3: Score graph of an average trainee

2. Method
In this simulator, the trainee is evaluated based on three parameters, viz., economy of distance, economy of time and the negative marks to penalize an incorrect action during the training of a particular exercise. Thirty-eight residents and thirteen experienced surgeons (total 51 subjects) participated in this study. Each subject completed all seven tasks thrice a day for a week. The data was analyzed to evaluate the individual subject’s performance by the scoring system in the simulator. Figure 3 shows the graph of an average trainee. The subjects were also evaluated by using a standard test procedure (paper-cutting test) on a pelvi-trainer in the beginning and at the end of the session.

3. Results
The first prototype of BEST-IRIS Laparoscopic Simulator includes 7 exercises. The user interface component provides a tool to store the trainee information, and the VR simulation system is used for skill training. The VR training environment contains abstract virtual anatomical structures and simulates endoscope, surgical instruments and object behavior. It also records the complete training session and stores the scores during the same.
The scores obtained by surgeons and residents were compared. The surgeons were found to perform significantly better. There was a clear demarcation in the scores noted between the experienced surgeons and the residents. This was proved by a statistical analysis (P<0.05). This was also in agreement with the “paper-cutting test” results. Thirty six out of thirty eight residents improved with practice. With an objective that 90% of residents would improve their skills by practicing on this system, statistical analysis has shown to be significant at a P value of < 0.05.

4. Conclusion
The result validates the BEST-IRIS Virtual Reality training module as a useful tool for training and assessment of psychomotor skills for laparoscopic surgery. The simulator has gone through the different stages of design, development, debugging and clinical trials and is now ready for commercialization.


5. References
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[2] Derossis AM, Fried GM, Abrahamowicz M, Sigman HH, Barkun JS, Meakins JL., “Development of a model for training and evaluation of laparoscopic skills”, Am J Surg 1998 Jun; 175(6):482-7.
[3] Mackay S, Morgan P, Datta V, Chang A, Darzi A., “Practice distribution in procedural skills training: a randomized controlled trial”, Surg Endosc 2002 Jun; 16(6):957-61.