A quantitative scale to define endoscopic torque control during natural orifice surgery.

INTRODUCTION

The drive to perform procedures with the least impact on the patient has meant that interest in natural orifice translumenal endoscopic surgery (NOTES) continues to proliferate. However, endoscope control within the extralumenal environment remains a significant challenge. This study aims to define a method to quantitatively assess endoscopic torque control as an indication of performance.

MATERIAL AND METHODS

Fourteen endoscopists performed a ten-target navigational task within a simulated NOTES environment whilst wrist movements were tracked with an optical motion tracker. Patterns of wrist movements were translated to a binary form enabling differentiation of the specified movement from no movement. Three patterns were discernable suggesting the discrimination of purposeful over random manipulations. Three independent assessors scored 140 patterns on a scale of 1 to 3 determined by which pattern was the most appropriate fit.

RESULTS

Mean score for novices was 16 (± 3) and for clinicians 22 (± 7). Inter-rater reliability (kappa statistic function) between the assessors ranged from 0.637 to 0.751 p < 0.001 referred to as a substantial assessment tool. The internal consistency between all variables using Chronbach's alpha function was 0.948 (p < 0.001).

CONCLUSIONS

Pattern of movements extrapolated from the wrist can be used as a method of measuring endoscope torque control during a translumenal navigation task.