Endoscopic ultrasound in clinical practice.

Endoscopic ultrasonography (EUS) is an accurate technique for the diagnosis and staging of benign and malignant lesions in the gastrointestinal tract and the mediastinum. EUS overcomes the limitations of other imaging diagnostic methods and gives the possibility to obtain tissue for histologic diagnosis (EUS guided FNA). The most useful indications of EUS are differentiation of submucosal tumors, staging for neoplasia, examination of the pancreato-biliary system and therapeutics. EUS can distinguish extrinsic compressions from intramural lesions and defines their nature (solid, cystic or vascular) and origin. EUS is useful for local staging of esophageal, gastric, duodenal, and rectal cancer using the TNM (tumor, node, metastases) system, as well as for diagnosing and staging of pancreatic lesions. The addition of EUS-guided FNA has improved the ability to detect malignant lymph node invasion. EUS is also highly sensitive for the diagnosis of choledocholithiasis, avoiding unnecessary danger of diagnostic ERCP. New therapeutic indications of EUS include drainage of pancreatic pseudocysts and abscesses and celiac plexus block and neurolysis. EUS has become an indispensable diagnostic method in gastroenterological everyday practice and should be part of most endoscopy units.