Pancreatic Walled-Off Necrosis: Cross-Sectional Imaging Depiction of Debris Predicts the Success of Endoscopic Drainage Using Lumen-Apposing Metal Stents.

Introduction: The use of endoscopic ultrasound (EUS)-guided transmural stent placement for pancreatic walled-off necrosis (WON) drainage is widespread. This study retrospectively analyzed imaging parameters predicting the outcomes of WON endoscopic drainage using lumen-apposing metal stents (LAMS).

Methods: This study analyzed the data of 115 patients who underwent EUS-guided debridement using LAMS from 2011 to 2015. Pre-intervention CT or MRI was used to analyze the total volume of WON, percentage of debris, multilocularity, and density. Success measures included technical success, the number of endoscopic sessions, the requirement of percutaneous drainage, long-term success, and recurrence.

Results: The primary cause of pancreatitis was gallstones (50.4%), followed by alcohol (27.8%), hypertriglyceridemia (11.3%), idiopathic (8.7%), and autoimmune (1.7%). The mean WON size was 674 mL. All patients underwent endoscopic necrosectomy, averaging 3.1 sessions. Stent placement was successful in 96.5% of cases. Procedural complications were observed in 13 patients (11.3%) and 6 patients (5.2%) who needed additional percutaneous drainage. No patients reported recurrent WON posttreatment. Univariate analysis indicated a significant correlation between debris percentage and the need for additional drainage and long-term success (p < 0.001). The number of endoscopic sessions correlated significantly with debris percentage (p < 0.001).

Conclusion: Pre-procedural imaging, particularly debris percentage within WON, significantly predicts the number of endoscopic sessions, the need for further percutaneous drainage, and overall long-term success.