A New Device for the Assessment of Minimally Invasive Surgical Performance – the Validity of Sequitor.

Objective
Several methods are currently used in the assessment of surgical performance. The majority depends on repeated expert review of an observed procedure. Sequitor allows identification of skilled motor behaviour using quantitative objective measures to provide additional performance characteristics, which may be advantageous during the acquisition of minimally invasive surgical skills.

Description and Methods
A customized, novel software solution called Sequitor was developed on request by PAM Systems to obtain motion tracking data characteristics from a 3D Guidance system (TrakStar, Ascension Technologies). Data were retrieved from electromagnetic sensors secured to laparoscopic instruments. 20 novices and 20 expert laparoscopic surgeons performed a series of sequential standardized skills tasks using Sequitor in a laparoscopic simulator. Each participant performed 10 repetitions of 4 validated skills tasks. Data recorded during repetition 1 and repetition 10 included total path length, motion smoothness and grasping frequency.

Results
There was a significant improvement in mean motion tracking data performance characteristics recorded for experts compared to novice surgeons. Mean path length (cm), motion smoothness (cm/s3) and grasping frequency (rads) for novices compared to experts respectively were 798.46, (s.e.m= 75.8) vs. 136.08 (s.e.m= 9.2) (P=<0.001), 6.05 (s.e.m= 0.33) vs. 7.18 (s.e.m= .016) (P=0.003) and 19.67 (s.e.m= 1.17) vs. 8.15 (s.e.m= 0.45) (P= <0.001). Median path length (cm), motion smoothness (cm/s3) and grasping frequency (rads) for novices compared to experts respectively were 451.1 vs 99.1, 4.94 vs. 7.03, 14.62 vs. 6.61.

Conclusion
Sequitor enables acquisition of motion tracking data to objectively quantify performance. The device can distinguish surgeons of variable skill level and demonstrates construct validity in a simulated setting. Further evaluation is required to identify its potential role in monitoring progress of surgical trainees in both simulated and operative settings.