Guidewire-assisted technique for gastroscope insertion through stricture of Zenkerʼs diverticulum for esophageal endoscopic submucosal dissection - Kasuga, Kengo; Abe, Seiichiro; Oda, Ichiro; Yoshinaga, Shigetaka; Suzuki, Haruhisa; Uraoka, Toshio; Saito, Yutaka (Endoscopy, 2021)