Objective
To standardize introduction to transoral robotic surgery (TORS), we designed a training program based on the da Vinci Mimic Virtual Reality Simulator and tested the feasibility of training robotic surgery naïve subjects using the simulator.
Study Design
Cross-sectional prospective study

Setting
Academic tertiary referral center

Subject and Methods
Sixteen medical students with no robotic surgery experience, were trained with the simulation program on the da Vinci Surgeon Console. Participants had unlimited console time and attempts to perform 12 exercises relevant to TORS until competent. Competence was achieving an overall score ≥91% for each exercise, calculated by preprogrammed simulator exercise metrics. Total training time (TTT) required to achieve competence was recorded, along with values for all metrics. Each participant was randomly assigned to follow-up 1, 3, 5, or 7 weeks post-training (n=4 per group) and repeated the exercises until regaining competence. Participants had no exposure to the console or simulation between initial training and follow-up. Follow-up total time (FTT) to re-achieve competence was recorded.
Results
All participants successfully completed training, becoming competent. Average TTT was 3.27 ± 1.22 hours. TTT distribution was bimodal rather than a normal distribution (Figure 1A), dividing the subjects into Short Training Time (STT)(n=10, 62.5%), and Long Training Time (LTT)(n=6, 37.5%) groups. TTT was 2.44 ± 0.56 hours for the STT group and 4.66 ± 0.46 hours for the LTT group(p = 0.0003). Difference in average time for the exercises was insignificant between STT and LTT (p = 0.635), but the total number of exercise attempts needed to complete training was significantly different (p = 0.003) with a mean 54.7 ± 14.8 and 100.2 ± 16.2 attempts respectively. STT and LTT differences in final score was insignificant (p = 0.635). All participants were able to re-achieve competence. Average follow-up total time (FTT) was 44 ± 5 min, 63 ± 3 min, 59 ± 23 min, and 82 ± 21 min for 1-, 3-, 5-, and 7-weeks groups respectively; all significantly shorter than TTT (p = 0.014, 0.014, 0.029, 0.014 respectively). The larger standard deviations at 5- and 7-weeks compared to 1- and 3-weeks were due to divergence between STT and LTT subjects (Figure 1B). While there was no significant difference between STT and LTT in average FTT for follow-up at 1 and 3 weeks, (p = 0.786) there were significant differences in FTT at 5 and 7 weeks (p = 0.036). There were no differences between STT and LTT in follow-up final score (p=0.118).

Conclusion
Physicians in training are able to acquire and retain robotic surgery competency using the simulator but exhibit declines in skill over time during a hiatus from training. STT subjects, had a slower decline in robotic skills. Upon retraining all subjects were able to regain equivalent competence. This information can establish a simulator training program for residents prior to clinical introduction to TORS. It also provides a benchmark for determining necessary TORS surgical volume or simulator training, to maintain competency.