A Change in Scope: Endoscopic Retrograde Cholangiopancreatography via a Gastroscope in Billroth II Gastrojejunostomy.

Previous gastric procedures often make endoscopic interventions challenging. Our case study focuses specifically on performing an endoscopic retrograde cholangiopancreatography (ERCP) through a gastroscope (EVIS EXERA III GIF-HQ190, Olympus, Center Valley, USA) in a patient with a history of Billroth II gastrojejunostomy. Successful ERCP in Billroth II using a gastroscope with traditional ERCP instrumentation has been very rarely reported in case reports in the literature review. This case study provides an alternative method of access to the common bile duct (CBD) and treatment of obstruction to prevent the risk of morbidities from an open CBD exploration. The primary diagnosis for this patient was choledocholithiasis. He initially underwent a standard ERCP with a side-viewing duodenoscope (EVIS EXERA II, TJF-Q190V, Olympus, Center Valley, USA); however, due to the difficult anatomy from his previous Billroth II reconstruction, the CBD was very difficult to access. A gastroscope was then used instead to perform the ERCP, providing an innovative endoscopic therapy. Given the patient's multiple comorbidities, he was at high risk for morbidity and mortality with an open CBD exploration. Hence, this case report provides insight into an innovative endoscopic approach to CBD exploration with difficult anatomy.