In-vivo Force Sensing during Laparoscopic Sacrocolpopexy Vaginal Vault Manipulation

Objective: During laparoscopic sacrocolpopexy vaginal vault prolapse is repaired by restoring the anatomical state ofthe vagina with a surgical mesh. A vaginal manipulator is placed inside the vagina to provide proper exposure to the surgeon forfixation of the mesh on the vaginal surface and vault by laparoscopy. Vaginal vault manipulation is done manually by an assistantand long operation times lead to fatigue and inconsistent application of tensioning forces. This work describes a novel force sensordesigned to be integrated in the vaginal manipulator to measure interaction forces between the vaginal vault and the manipulator.Methods: A sterile and biocompatible way to use the sensor has been developed and tested. After receiving ethics committee approvaltwo first-in-woman studies have been conducted. Both the force and pose of the instrument were recorded. Results: In the first case,average forces of 4.41 N were measured with a standard deviation of 2.42 N, the maximal force was 27.48 N. In the second casethe force was 10.87 N (mean), 7.36 N (std) and 47.28 N (max). No vaginal rupture occurred. Conclusions: Different forces coincidedwith a different degree of prolapse which may cause differences in compliance. In order to draw proper conclusions about themeasured data, a total of thirty interventions will be recorded. Clinical Impact: Up to now, no previous research has quantifiedthese interaction forces. Quantifying these forces and providing feedback cues to the assistant is of particular interest, especially asa means to avoid vaginal rupture due to over-tensioning.