Bimanual Robotic Eye Manipulation Using Adaptive Sclera Force Control: Towards Safe Retinal Vein Cannulation

Area of Science:

• Ophthalmology
• Robotics
• Surgical Technology

Background:

• Retinal vein cannulation (RVC) is a complex microsurgery requiring precise bimanual instrument control.
• Hand tremors pose a significant challenge in freehand RVC due to the small size of retinal vessels.
• Robot-assisted surgery offers enhanced precision and tremor reduction for RVC.

Purpose of the Study:

• To develop and validate a novel bimanual adaptive cooperative (BMAC) control framework for robot-assisted retinal surgery.
• To ensure patient safety by minimizing scleral interaction forces during bimanual robot manipulation.
• To overcome limitations of traditional kinematics-based control and robot registration.

Main Methods:

• Implemented a BMAC control framework with independent robot control.
• Utilized a hybrid adaptive position-force control algorithm for each robot.
• Employed fiber Bragg grating-based force-sensing surgical instruments for precise force monitoring.
• Validated the system through a pilot study with five users on an eye phantom.

Main Results:

• The BMAC framework successfully minimized tool-sclera interaction forces.
• Scleral forces were maintained within a safe threshold, preventing over-stretching.
• The system demonstrated effectiveness in a vessel-following experiment on an eye phantom.
• Pilot study participants successfully performed the task under surgical microscope visualization.

Conclusions:

• The developed BMAC control framework enhances safety in robot-assisted retinal vein cannulation.
• This approach effectively manages scleral interaction forces without traditional RCM constraints or registration.
• The system shows promise for improving precision and safety in challenging ophthalmic microsurgeries.