Peter Uhrík, Lenka Nosáková, Peter Bánovčin, Zdenko Huťka, Rudolf Hyrdel
Endoscopic ultrasound (EUS) is a specific endoscopic examination used to diagnose various types of gastrointestinal tumours. The close contact of the ultrasonographic probe with the gastrointestinal wall allows a detailed description of the tumour and extent of its infiltration. An essential role of the EUS was found in the diagnostics of neuroendocrine tumours of the gastrointestinal tract (GEP NETs). ‘Functional’ GEP NETs can only be a few millimetres large, imaging methods like CT and MRI often fail to localize them, while the EUS can also display such small lesions. In recent years, other modalities have been developed, which in combination with the EUS, improve diagnosis, give a detailed description about the invasion into surrounding structures, and allow prediction of the tumour’s biological behaviour. Such methods include contrast ultrasonography, elastography, and EUS navigated fine needle aspiration. This article aims to introduce the principles of these methods and the possibilities of their use in everyday practice.