An Ex-vivo Demonstration of a Robotic Laser Tissue Soldering System

Background: Fast and reliable incision closing is critical in any surgical intervention, and presents a challenge to the surgeon. Common solutions are sutures, clips or adhesives, but they all present difficulties. These difficulties are especially pronounced in minimally-invasive interventions. Laser soldering provides a promising alternative to suturing by connecting the tissues with heat formed by a laser beam, but it is still not reproducible.

Aims: We present a novel robotic laser tissue soldering system (RLTS), which integrates laser soldering with a robotic system and demonstrates its feasibility on incisions in ex-vivo mice skins.

Methods: The laser was a custom made, Fiber-Coupled, Semiconductor Disc Laser operating at λ=1900 nanometers, and the laser intensity was controlled to a constant temperature of 60^oC with a controller based on temperature feedback. The laser applicator was mounted on the Raven II (Applied Dexterity) surgical robot, which was moved over an incision autonomously over a predefined trajectory. Such automated RLTS holds the potential to result in reproducible bond-strength, avoid tissue damage, and reduce post-operative complications.

Results: We demonstrated RLTS soldering of incisions in mouse skin. We measured the mechanical strength of the resulting bonded tissue by measuring tearing forces. We recorded ~2.5N tearing strength, 73% of the tearing force of an uncut natural mouse skin.

Conclusions and discussion: We demonstrated the feasibility of our RLTS system. In future studies, we will optimize the system towards integration with clinical RAMIS systems and other robotic platforms. This technique has the potential to revolutionize surgical tissue bonding.