Endosonographic imaging with catheter probes

Most endoscopic ultrasound (EUS) evaluations involve an echoendoscope. However, small catheter ultrasound probes have been developed and expand the armamentarium for EUS imaging within the gastrointestinal tract, pancreas, or biliary tree. These miniprobes or catheter EUS probes (C-EUS) can be passed through the accessory channel of a standard endoscope. They provide excellent high-resolution images of the gastrointestinal tract (GIT) wall, ampulla, bile duct, and pancreatic duct because of generally higher sonographic frequencies. They are readily available, easy to use, require minimal technical manuevering, and add little to procedure time. This review discusses the available and soon-to-be-available probes, technique, clinical applications, advantages and disadvantages of C-EUS, and future technical developments.