Fig. 1. A flowchart of the study. A total of 11 patients were enrolled; 9 required no additional endoscopic interventions, and the primary outcome was achieved in 10 patients. VARD, video-assisted retroperitoneal debridement.

Fig. 2. Magnetic resonance imaging (MRI) of pediatric patients with walled-off necrosis (WON). Axial T2-weighted MRI images of four pediatric patients demonstrate large, well-encapsulated WON marked by black asterisks (*). (A) A heterogeneous fluid collection with internal debris located in the pancreatic and peripancreatic region. (B) A predominantly cystic WON located in the lesser sac, exerting mass effect on adjacent structures. (C) A large encapsulated collection with a fluid-debris level occupying most of the upper abdomen, displacing the stomach and bowel loops. (D) A clearly demarcated fluid collection with minimal internal debris located near the pancreatic tail.

Fig. 3. (A, B) Endoscopic images depict lumen-apposing metal stent draining solid necrotic debris (marked with *). (C, D) Endoscopic ultrasound images depict walled-off necrosis (WON) (I depicts the liquid component and II is the necrotic debris) and the endoscopic ultrasonography needle in the WON cavity.

Graphical abstract