[Endoscopic ultrasonography in the diagnosis and follow-up of gastrointestinal diseases].

Endoscopic ultrasonography provides detailed images of gastrointestinal structures by means of high frequency ultrasound transducers placed within the gastrointestinal tract. In this paper, the authors describe various systems and discuss their clinical potential and indications for use. Endoscopic ultrasonography allows imaging of various small pathological lesions in the visceral wall and adjacent structures, such as the mediastinum, pancreas and distal parts of the bile duct. Experience in endoscopy and ultrasonography is necessary for a proper management of the technique.