Ultrasound probe for detection of external structures in fluids

The invention relates to an ultrasound probe for determining and / or monitoring and / or size determination of the occurrence of foreign structures in an extracorporeal fluid or an extracorporeal fluid stream, in particular air bubbles. The extracorporeal fluid is passed, for example, through a hose and the probe comprises a housing, an ultrasonic sensor, a sound field, a reflector, a carrier material, a damping body and at least one piezoceramic. a homogeneous sound field is produced in the measurement volume by a suitable construction of the probe. Furthermore, the invention relates to a method for determining and / or monitoring the occurrence and / or size determination of extraneous structures, in particular air bubbles, in an extracorporeal fluid or an extracorporeal fluid flow, with the aid of the ultrasonic probe of the invention and an evaluation means.