Endoscopic Ultrasonography

Endoscopic ultrasonography (EUS) is a versatile tool that can be used to perform a variety of diagnostic and therapeutic procedures in the upper or lower gastrointestinal tract. The proximity of the echoendoscope to the pancreas, liver, and other thoracic and abdominal organs allows detailed examination or minimally invasive intervention that would not be feasible by surgical or percutaneous approaches. EUS is available with radial or linear scanning arrays and is capable of guiding fine-needle aspiration to acquire tissue for cytologic analysis. This review covers the role of EUS in chronic pancreatitis; pancreatic cysts; submucosal tumors; suspected choledocholithiasis; fecal incontinence; staging of malignancy in esophageal, pancreatic, gastric, and rectal cancer; celiac plexus block/neurolysis; fiducial placement; pseudocyst drainage and cystogastrostomy/cystoduodenostomy; endoscopic necrosectomy; and biliary drainage. Figures show peripancreatic cysts, gastrointestinal stromal tumor, common bile duct stone, esophageal adenocarcinoma, pancreatic head mass causing biliary obstruction and invading portal confluence, fine-needle aspiration of a pancreatic head mass, rectal adenocarcinoma, abdominal aorta with celiac artery and superior mesenteric artery, celiac plexus neurolysis, necrosectomy, and EUS-guided choledochoduodenostomy for failed endoscopic retrograde cholangiopancreatography. Tables list the Rosemont criteria for chronic pancreatitis and pancreatic cystic lesions.   Key words: bile duct stone, biliary drainage, echoendoscope, endoscopic ultrasonography, fine-needle aspiration, pancreatic cyst   This review contains 12 highly rendered figures, 2 tables, and 62 references.