Kangbuk Samsung Hospital in South Korea Validates Precision of New-Generation Surface-Guided Radiation Therapy System

The research team from the Department of Radiation Oncology at Kangbuk Samsung Hospital in South Korea announced on July 31 that they have completed validation of the geometric accuracy and respiratory tracking performance of a new-generation surface-guided radiation therapy system. The research findings have been published in the latest issue of the international academic journal *Radiation Physics and Chemistry*.

In breast cancer radiotherapy, the deep inspiration breath-hold technique is commonly used in clinical practice to reduce radiation exposure to the heart and lungs. Traditional procedures typically require tattoo marks or drawn guide lines on the patient's skin surface, along with wearing sensors to monitor respiratory motion, which somewhat compromises treatment convenience and patient comfort.

The new-generation surface-guided radiation therapy system validated in this study utilizes 3D stereoscopic cameras and thermal imaging technology to observe the patient's skin surface and its motion in real time. The system enables position tracking and respiratory monitoring without the need for surface markers or additional sensors worn by the patient.

The research team conducted three-phase experiments using phantoms capable of simulating human anatomy and respiratory motion, including verifying the positional repeatability of the 3D surface imaging system, comparing positional accuracy with existing 3D image-guided radiation therapy systems, and evaluating real-time respiratory tracking capability using a four-dimensional dynamic model.

Results showed that the system maintained positional deviations within 0.3 mm, 0.3 mm, and 0.7 mm in the left-right, vertical, and longitudinal directions, respectively; compared with existing image-guided radiation therapy systems, positional errors remained within 1 mm, demonstrating positioning accuracy comparable to traditional methods. Respiratory motion amplitude differences were less than 0.3 mm, and the respiratory signals obtained by the surface-guided system were nearly identical to those from existing sensor-based devices.

The researchers stated that while maintaining the accuracy of existing methods, the system is expected to improve patient treatment experience and enhance the convenience and safety of breast cancer radiotherapy. The team also plans to further explore its application potential in organs requiring respiratory-gated radiotherapy, such as lung cancer and liver cancer.