Endoscopic add-on stiffness probe for real-time soft surface characterisation in MIS

Area of Science:

• Biomedical Engineering
• Surgical Technology
• Medical Devices

Background:

• Minimally invasive surgery (MIS) requires advanced tools for tissue characterization.
• Accurate assessment of tissue stiffness is crucial for differentiating diseased from healthy tissue, particularly in tumor localization.
• Existing methods for intraoperative stiffness assessment can be complex or invasive.

Purpose of the Study:

• To develop and validate a novel, purely mechanical stiffness sensor for laparoscopic cameras.
• To enable real-time stiffness computation during minimally invasive procedures.
• To enhance tumor detection and characterization in soft tissues.

Main Methods:

• A novel stiffness sensor integrated with a laparoscopic camera was designed.
• The sensor utilizes two pairs of spheres connected to springs with known constants.
• Visual analysis of sphere tracker movement and diameter changes within the camera's field of view was employed.
• A mathematical model related visual data to surface stiffness.

Main Results:

• The sensor successfully computed stiffness when interacting with soft surfaces.
• Tests using silicon phantoms demonstrated the system's capability to differentiate varying stiffness levels.
• Sensing accuracy improved with increased tissue softness.

Conclusions:

• The developed stiffness sensor is a promising tool for minimally invasive surgery.
• Real-time stiffness measurement via visual analysis offers a non-invasive method for tissue characterization.
• This technology can potentially improve tumor localization and surgical outcomes.