[Ultrasonography in the monitoring of internal biliary drainage using an endoscopically inserted prosthesis].

Endoscopic retrograde biliary drainage by means of transtumoral endoprostheses is an effective technique for palliative decompression of malignant biliary obstruction. However, serial follow-up is required for an early detection of eventual long-term complications. In the present study 37 patients with malignant biliary obstruction, treated by endoscopic insertion of one or more biliary stents, were prospectively evaluated by sonography, with serial clinical and US examinations up to 10 months. In our experience, sonography could correctly identify both the endoprostheses and their location in the biliary tract. Most important, sonography has proved to be a sensitive method to detect possible stent dysfunctions, besides providing with information about the progression of the underlying malignancy.