During endoscopy, the extent of Barrett’s esophagus (BE) is quantified by endoscopists using the widely accepted Prague C&M (circumferential and maximal lengths) criteria. Prague C&M scores can be used to assess the risk of progression but are subjective to endoscopists and their level of experience.
This single-center pilot study evaluated a novel artificial intelligence (AI)-assisted, automatic, 3-dimensional (3D) system for measuring BE depth and length using the Prague C&M classification system. Initially, an advanced deep learning model was developed by mapping 2-dimensional real-world endoscopy images, which were compared to a 3D phantom esophagus derived from CT and endoscopic images. Measurements of C and M lengths taken during endoscopy were then compared to those of the phantom esophagus ground-truth. The AI system was trained on 10,000 simulated images and validated using 2000 images (20%) for approximately 1000 epochs (100 hours).
The automatic quantification of the C and M extent had an accuracy of 97.2% (2.8% relative error) and an average deviation of 0.9 mm from the ground-truth measurements. The root mean square error was 1.2 mm, confirming substantial agreement with the ground-truth (Cohen's kappa [k]=0.72 and Spearman correlation [rs]= 0.99). C and M measurements made by endoscopists during real-time patient endoscopy in 131 patients were compared to the automated measurement system.
This endoscopy patient cohort comprised 3 subgroups: newly diagnosed BE patients (n=68), BE patients undergoing follow-up without endoscopic therapy (n= 24), and patients with comparison of pre-endoscopic and postendoscopic therapy visits (n= 39). For all patients, the overall relative errors (mean difference) were 8% (3.6 mm) and 7% (2.8 mm) for C and M values, respectively. The highest relative errors were experienced in those patients with BE lengths of 0 to 1 cm. Near-perfect interrater reliability was found between the AI system and endoscopists (k=0.84 and rs=0.99 for C; k=0.87 and rs=0.99 for M).
Ali S, Bailey A, Ash S, et al. A pilot study on automatic three-dimensional quantification of Barrett’s esophagus for risk stratification and therapy monitoring. Gastroenterology