Introduction
Over time, endoscopic ultrasound (EUS)-guided therapy has become the preferred modality of treating pancreatic fluid collections (PFCs) and walled off necrosis (WON). Endoscopic retrograde cholangiopancreatography (ERCP) with biliary stent placement is often necessary if biliary obstruction is present. We describe three cases of large PFC/WON resulting in extrinsic biliary obstruction treated successfully with EUS-guided cystogastrostomy (EUS-C) decompression using lumen-apposing self-expanding metal stents (LAMS) without the need for ERCP or biliary drainage.
Cases
Patient 1: 38-year-old female with necrotizing pancreatitis WON causing biliary obstruction. CT imaging revealed an 11x 23x 9cm WON. ERCP was unsuccessful due to variant anatomy thus EUS-C with LAMS was performed with successful decompression of WON and biliary obstruction.
Patient 2: 48-year-old male with necrotizing pancreatitis WON resulting in jaundice. Imaging revealed a 17x 13x 6cm multiloculated WON, the largest obstructing the duodenum and common bile duct (Figure 1). ERCP attempted due to suspected choledocholithiasis but was unsuccessful due to edema. EUS-C however relieved the extrinsic biliary obstruction with subsequent imaging not revealing choledocholithiasis. Necrosectomy sessions led to complete resolution over the next few weeks (Figure 2).
Patient 3: 30-year-old male with a history of cirrhosis who presented with acute on chronic pancreatitis. CT revealed a 12x 4x 34cm multiloculated pancreatic pseudocyst obstructing the common bile duct. EUS-C was performed resulting in complete resolution of symptoms and cyst decompression within a few days.
Discussion
In all three cases of acute extrinsic biliary obstruction, EUS-C with LAMS was successful, with none requiring follow-up ERCP or surgical intervention. With advances in endoscopy and stent technologies, EUS-C is a safer, more efficient, tool to use in a wide variety of settings. In certain cases of biliary obstruction, EUS-C drainage with appropriate surveillance may eliminate the need for further interventions including ERCP or surgical or percutaneous options.

Figure 1: Large pancreatic pseudocyst (blue arrow) compressing bile duct and leading to biliary dilation (yellow arrow).

Figure 2: Post-cystgastrostomy (yellow arrow) decompression of pseudocyst with resulting relief of biliary obstruction

Bhavi Trivedi

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