Diagnosis of Gastrointestinal Subepithelial Lesions Using a Novel Endoscopic Ultrasonography Imaging Technique

Aims Gastrointestinal stromal tumors (GIST) are the most common malignant subepithelial lesions (SELs) in the GI tract. Due to GIST's notable vascularity and deep location, endoscopic ultrasound (EUS) is the first-line diagnostic approach. Color-doppler EUS, power-doppler EUS, and e-FLOW EUS, are useful for real-time vascularity detection; however, they are not effective for fine/slow flow vessel detection. Therefore, contrast enhanced EUS (CE-EUS) is proposed as a first-line approach. To avoid contrastrelated adverse events, a novel diagnostic method, detective flow imaging endoscopic ultrasonography (DFI-EUS) has emerged. We aim to evaluate the utility of DFI-EUS in the diagnosis and differentiation of gastrointestinal SELs (GIST and leiomyomas) in comparison to CE-EUS.