A System for Characterizing Intraoperative Force Distribution During Operative Laryngoscopy

Area of Science:

• Surgical instrumentation
• Biomedical engineering
• Medical device development

Background:

• Trans-oral surgery requires precise control of forces to minimize soft-tissue damage.
• Quantifying forces applied by surgical instruments like laryngoscopes is crucial for patient safety.
• Existing methods for measuring intraoperative forces are limited.

Purpose of the Study:

• To develop and validate an integrated data acquisition system for measuring force distribution.
• To gauge the forces exerted by a laryngoscope on soft tissues during trans-oral surgery.
• To provide real-time intraoperative feedback to surgeons.

Main Methods:

• Integrated 16 piezoresistive force sensors into a laryngoscope and custom maxillary tooth guard.
• Developed a calibration protocol using a motor-controlled linear stage and validated against a digital scale.
• Tested the system on cadaver heads and during intraoperative head and neck tumor resections.

Main Results:

• Achieved mean calibration errors below 150 g for scope sensors and 200 g for maxilla sensors.
• Recorded peak scope forces up to 8.09 kg and maxilla forces up to 7.62 kg in cadaver trials.
• Measured peak intraoperative scope forces of 24.7 kg and maxilla forces of 22.0 kg.

Conclusions:

• The developed data acquisition system successfully recorded intraoperative force distribution.
• Further evaluation is needed in diverse patient anatomies and procedures.
• The system offers a low-cost solution for characterizing retraction forces and informing surgical models.