Surgery: more accuracy and safety through smart laser technology

Researchers at the University of Basel have developed a smart laser that could be used to cut bone in surgery. The laser simultaneously cuts and analyzes tissue and measures the cutting depth. It could open new applications for laser surgery in the future and make it much safer for the patient while causing less damage to surrounding soft tissue.

In this interview with MEDICA-tradefair.com, Dr. Ferda Canbaz explains the current state of research and the areas in which the laser can be used.

Dr. Canbaz, could you start by explaining how this system differs from traditional surgical methods?

Dr. Ferda Canbaz: Unlike traditional methods where surgeons rely on intuition to feel and visualize tissue types, our system uses additional optical systems like spectroscopy (LIBS) and optical coherence tomography (OCT). The LIBS system decides the tissue type to cut, and the OCT system allows for precise visualization of cutting shapes, setting profiles, and tissue depth. This is particularly valuable in delicate procedures especially at the borders of hard tissues while minimizing damage to surrounding soft tissues.

Can you give an example of how the laser works?

Canbaz: The process begins by scanning a specific area, to identify the soft and hard tissues. This is achieved by applying only two slightly invasive laser pulses and create a tissue map on the surface. Then the optical system continues cutting the bone area while preventing the laser from reaching to soft tissue. This safety feature ensures the system recognizes where soft tissue is located unless it is deactivated. Once the laser starts cutting bone tissue, it continuously monitors its position. Upon reaching soft tissue, the laser automatically stops to prevent damage.

This is crucial because soft tissues, due to their high water content and high absorption, can be damaged by the ablation laser. Hard tissue like bone is denser and is not ablated as quickly.

The system undergoes rigorous testing with bone samples to ensure these aspects. It incorporates features to prevent inadvertent damage to soft tissues, such as scanning and identifying soft tissue areas before initiating laser ablation.

Canbaz: Protecting soft tissues is a priority in our process. While we continue to enhance accuracy and performance of the ablation process, we are cautious about the risks of directing the ablative laser at soft tissue because we also include nerves and muscles as soft tissues in our experiments. As in the current system, we do not only have a single safety feature, but we also always have a secondary measurement supporting it.

Utilizing lasers significantly enhances the safety of bone-cutting procedures, with the added benefit of considerably lower thermal load compared to conventional tools. This not only safeguards the soft tissue in the surrounding area but also protects the adjacent bone tissue along the cutting line.

When the tissue differentiation laser hits soft tissue, it causes tiny explosions. These explosions result in small particles adhering to the bone, leading to the misidentification of these areas as soft tissue. To address this, we employ a nearest neighbor approximation analysis. This method involves examining the four closest neighboring points of the tissue. If all four indicate either soft or hard tissue, we proceed with the ablation.

Our decision to apply the laser is not based solely on the immediate point of analysis, but also on the surrounding context. If there is any uncertainty about the tissue type, we refrain from using the laser.

Looking to the future, how do you envision the development and application of this technology?

Canbaz: We are part of the MIRACLE Project, aiming to evolve this smart laser system into a compact, endoscopic device. The development in this project was part of the PhD thesis of Dr. Arsham Hamidi. In addition, we appreciate all the contribution from all our team members.

Our team is working on engineering components that fit into smaller endoscopic devices while maintaining high ablation rates and precise energy delivery. We see vast potential for this technology in various medical applications beyond bone cutting.

Can you elaborate on the advantages this system offers over traditional surgical methods?

Canbaz: Our system eliminates the thermal load associated with metal devices, providing a contactless, highly accurate, and visually comparable tool for surgeons. With a laser beam size as small as half a millimeter and resolution comparable to human eyes, it transcends limitations of traditional methods, offering unparalleled advantages in surgical precision and tissue handling.

Finally, what does the future hold for the smart laser system in terms of clinical trials and optimization?

Canbaz: We are continuously optimizing the system and exploring potential for clinical trials. The smart laser system represents a monumental leap forward in surgical technology, with the potential to enhance precision, minimize tissue damage, and revolutionize endoscopic procedures. It is a testament to the relentless pursuit of safer and more effective medical treatments.