Haptics has proven to be highly beneficial in surgical robotics, bringing enhanced safety and precision by complementing the surgeon’s visual channel. However, most of the research body in this context is dedicated to applications involving traditional “cold steel” surgical instruments. This research investigates new ways to bring the benefits of haptics to contactless surgeries.

Considering the case of robot-assisted laser microsurgery, we have developed a novel method to create a fictitious force feedback that allows the user to sense the surgical area haptically while controlling a non-contact surgical laser.

Our method is based stereoscopic visualization and 3D reconstruction. The high-quality haptic feedback produced is shown to significantly improve system usability and the accuracy of laser incisions.

The results of this research are applicable to different kinds of contactless focused energy surgery, such as radiation therapy and high-intensity focused ultrasound (HIFU) in addition to lasers. This is exciting because it allows the exploitation of active constraints and guidance techniques in many kinds of contactless surgeries, which can contribute to enhance surgical accuracy both in static and dynamic environments.

System components

The Haptic Laser Scalpel system is based on the following devices:

• Stereo camera for real-time 3D imaging of the surgical site
• 3D visualization device (3D display)
• Haptics stylus device
• Robotic laser micromanipulator system

These devices are interconnected by the system’s processing framework, as summarized by the following block diagram.

Block diagram of the HLS system.

System control

The control of the Haptic Laser Scalpel system is based on different coordinate system transformations linking the system devices. These enable positioning the laser spot on the real surgical site to precisely match the corresponding point touched by the user on the virtual haptic surface. In addition, the mappings allow the inclusion of a 3D graphical representation of the laser scalpel on the visual feedback provided to the user. This representation, called 3DHLS, precisely matches the position and orientation of the haptic stylus device and is consistent with the laser beam projection on the target surface.

The experimental results demonstrated the HLS contributed to significantly improving the laser control performance both in static and dynamic environments. This demonstrates that the artificial haptic feedback provided by the system can have a real impact on the performance of such contactless surgical procedures.

In addition, the results showed that enriching the haptic feedback provided to surgeons with augmented reality (AR) has the potential to further improve the usability and performance of the proposed technology. This was observed when providing an AR tool object to control the laser, which improved the user experience with the haptic device by making its positioning and orientation in space more intuitive, and thus leading to a proper use of this device to sense and act on the surgical scene.

Related publications

1. Olivieri, E., Barresi, G., Caldwell, D., Mattos, L., “Haptic Feedback for Control and Active Constraints in Contactless Laser Surgery: Concept, Implementation and Evaluation” IEEE Transactions on Haptics, vol. 11, issue 2, pp. 241-254, ISSN 1939-1412, 2018
2. Acemoglu, A., Fichera, L., Kepiro, I., Caldwell, D., Mattos, L., “Laser Incision Depth Control in Robot-Assisted Soft Tissue Microsurgery” Journal of Medical Robotics Research, Vol. 02, No. 03, September 2017
3. Mattos, L., Deshpande, N., Barresi, G., Guastini, L., Peretti, G., “A Novel Computerized Surgeon–Machine Interface for Robot-Assisted Laser Phonomicrosurgery” The Laryngoscope, vol. 124, pp. 1887–1894, 2014
4. Olivieri, E., Mattos, L., “Comparative Study of Haptic Libraries Performances for Deforming Objects” 5^th Joint Workshop on New Technologies for Computer/Robot Assisted Surgery (CRAS 2015), Brussels, Belgium, September, 2015
5. Olivieri, E., Mattos, L., “A New ROS Interfaced Haptic Library with an Example of Application” 4th Joint Workshop on New Technologies for Computer/Robot Assisted Surgery (CRAS 2014), Genoa, Italy, October, 2014
6. Deshpande, N., Ortiz, J., Caldwell, D., Mattos, L., “Enhanced Computer-Assisted Laser Microsurgeries with a ‘Virtual Microscope’ Based Surgical System” Proceedings of the 2014 IEEE International Conference on Robotics and Automation (ICRA 2014), pp. 4194 – 4199, Hong Kong, China, June 2014
7. Mattos, L., Dagnino, G., Becattini, G., Dellepiane, M., Caldwell, D., “A virtual scalpel system for computer-assisted laser microsurgery” Proceedings of the IEEE International Conference on Intelligent Robots and Systems, IROS 2011, 2011