Force-based Safe Vein Cannulation in Robot-assisted Retinal Surgery: A Preliminary Study.

Area of Science:

• Ophthalmology
• Robotics
• Surgical Technology

Background:

• Retinal vein cannulation (RVC) is a promising treatment for retinal vein occlusion (RVO).
• Manual RVC faces challenges due to small anatomical structures, delicate instruments, and surgeon hand tremor.
• Physiological movements like heartbeat can introduce unpredictable forces during retinal surgery.

Purpose of the Study:

• To develop and evaluate a force-based control strategy for robot-assisted RVC.
• To automatically compensate for retinal and corneal motion during the procedure.
• To maintain controlled tip and sclera forces within safe, predetermined limits.

Main Methods:

• A dual force-sensing tool was developed to monitor tip force, sclera force, and insertion depth.
• A modified admittance controller derived desired robot joint velocities based on sensor feedback.
• The control strategy was quantitatively tested and validated through experiments and a surgeon user study.

Main Results:

• The proposed force-based control strategy effectively compensated for retinal movement.
• The system successfully maintained tip and sclera forces within a narrow, safe range.
• User study demonstrated the advantages of the automatic compensation approach for retinal surgeons.

Conclusions:

• Robot-assisted retinal surgery with force-based motion compensation offers enhanced precision and safety for RVC.
• This technology has the potential to overcome limitations of manual RVC and improve outcomes for RVO patients.
• The developed control strategy represents a significant advancement in automated microsurgical procedures.