Improving thoracoscopic surgery training using eye tracking technology

Associate Professor Jingxi Chen of Tongji University and Dr. Liang Zhao of the Department of Thoracic Surgery at the Cancer Hospital of the Chinese Academy of Medical Sciences have formed an innovative research team dedicated to studying skill transfer in medical contexts. They have improved medical schools’ thoracoscopic surgery training by combining medical expertise with eye tracking. In their latest study, the team used the Tobii Pro Fusion and Tobii Pro Lab to investigate the significance of eye movement metrics as an objective testing standard for thoracic surgery training.

Nowadays, more than 90 percent of all thoracic surgeries are performed under a thoracoscope – a tiny, flexible tube with a camera on end, which allows surgeons to view inside the chest cavity. Thoracoscopic surgery presents new challenges to novice surgeons compared to the traditional open surgical approach. In thoracoscopic surgery, the tactile feedback from a hand or instrument is limited, and only visual feedback captured in a video by a thoracoscopic lens is available. In addition, most surgical skills training is based on the subjective judgment of the teaching surgeon and lacks objective assessment tools. All these factors adversely affect the training of novice thoracic surgeons.

Eye tracking reveals visual strategies in novice and expert surgeons

Eye tracking can effectively capture an individual’s visual attention and various cognitive processes. By recording eye movements in specific scenarios, the data obtained through eye tracking becomes a valuable source of information, shedding light on how an individual perceives their environment, processes information, and applies knowledge and skills. Eye tracking technology stands out as an innovative tool, enabling the training of new doctors through cued video training and offering a possibility for objective, instructional feedback throughout the learning process.

In the present study, the researchers wanted to know whether observing and replicating the expert surgeon’s eye movements in a thoracoscopic surgery video would enhance the learning process of novice surgeons. To address this question, the scientist performed a two-phase eye tracking study. They used the Tobii Pro Fusion eye tracker and Tobii Pro Lab for stimulus presentation, data collection, and analysis.

In the first experiment phase, the researchers tracked expert and novice surgeons’ eye movements while watching a thoracoscopic dissection video. In the analysis, the researchers looked into two main types of eye movement metrics within the specific areas of interest (AOI) and times of interest (TOI):

• Saccade-based metrics, which reflect the areas of cognitive processing and information acquisition.
• Fixation-based metrics, which allow gaining insight into the area of attention allocation, cognitive processing, and learning efficiency.

The study results revealed significant differences in gaze patterns between the two groups while watching the surgical video. While expert doctors focused longer on critical details in the video and paid attention to key anatomical structures, novice doctors tended to deviate their attention from the key regions and spent more time fixating on unrelated areas.

In the study’s second phase, a new cohort of novice surgeons was divided into two groups to watch the original surgical video (control group) and the same video with the expert’s eye movement trajectory attached (experimental group). Post-tests showed that the experimental group better understood the surgical procedure details, significantly improving their learning.

Publication

Ji, Y., Kong, Z., Deng, Y., Chen, J., Liu, Y., & Zhao, L. (2022). The role of eye tracker in teaching video-assisted thoracoscopic surgery: the differences in visual strategies between novice and expert surgeons in thoracoscopic surgery. Annals of Translational Medicine, 10(10), 592–592.