Endoscopic ultrasound: what is it and when should it be used?

Endoscopic ultrasound (EUS) is an increasingly available diagnostic and therapeutic tool used within the U.K. it has wide applications both in the gastrointestinal tract and mediastinum with its current main uses being in the staging of luminal malignancies and assessment of pancreatic and subepithelial lesions. The emergence of linear EUS has opened up new therapeutic avenues with fine needle aspiration, trucut biopsies, coeliac plexus blocks and transmural pseudocyst drainage all now possible. Future developments include localised brachytherapy/chemotherapy and alcohol ablation of unresectable pancreatic malignancies and EUS-guided endoscopic surgery.