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Identification of gaze pattern and blind spots by upper gastrointestinal endoscopy using an eye-tracking technique
Ayoung Lee1,2, Hyunsoo Chung3, Yejin Cho4
1Division of Gastroenterology, Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea.
Background:
The lesion detection rate of esophagogastroduodenoscopy (EGD) varies depending on the degree of experience of the endoscopist and anatomical blind spots. This study aimed to identify gaze patterns and blind spots by analyzing the endoscopist's gaze during real-time EGD.
Methods:
Five endoscopists were enrolled in this study. The endoscopist's eye gaze tracked by an eye tracker was selected from the esophagogastric junction to the second portion of the duodenum without the esophagus during insertion and withdrawal, and then matched with photos. Gaze patterns were visualized as a gaze plot, blind spot detection as a heatmap, observation time (OT), fixation duration (FD), and FD-to-OT ratio.
Results:
The mean OT and FD were 11.10 ± 11.14 min and 8.37 ± 9.95 min, respectively, and the FD-to-OT ratio was 72.5%. A total of 34.3% of the time was spent observing the antrum. When observing the body of the stomach, it took longer to observe the high body in the retroflexion view and the low-to-mid body in the forward view.
Conclusions:
It is necessary to minimize gaze distraction and observe the posterior wall in the retroflexion view. Our results suggest that eye-tracking techniques may be useful for future endoscopic training and education.
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