Current status of endoscopic ultrasound-guided tissue acquisition and endoscopic ultrasound-guided drainage

Endoscopic ultrasound (EUS) has both diagnostic and therapeutic clinical applications. This review article focuses on recent advances in two commonly performed procedures: EUS-guided tissue acquisition and EUS-guided drainage. There is a shift from acquiring aspirates for cytology to obtaining tissue cores for histological diagnoses and molecular analyses. There is growing interest and research about artificial intelligence in EUS. Artificial intelligence may potentially be useful to guide clinical decision making if biopsy results are non-diagnostic. The range of EUS-guided drainage procedures has expanded. EUS-guided drainage of walled-off pancreatic fluid collections is an accepted first line treatment option. EUS-guided palliative drainage of malignant biliary obstruction after unsuccessful endoscopic retrograde cholangiopancreatography (ERCP) is now an accepted alternative to percutaneous transhepatic biliary drainage. EUS-guided gallbladder drainage for management of acute cholecystitis is now a preferred option over percutaneous cholecystostomy for non-surgical candidates. Other EUS-created gastrointestinal anastomoses such as EUS-guided gastroenterostomy in the context of gastric outlet obstruction, and EUS-directed transgastric ERCP for Roux-en-Y gastric bypass are now technically feasible, but further prospective randomized studies are needed to establish the actual clinical impact.