The present invention relates to a catheter (20) adapted for open-loop irrigated ablation, such as RF ablation, of a tissue (40). Said catheter has a distal tip (22) with an ablation entity (15) adapted for performing ablation of the tissue, an irrigation hole (21) and an ultrasound transducer (5) adapted for transmitting and/or receiving ultrasonic waves. The ultrasound transducer is disposed behind or in the irrigation hole of the catheter, so as to allow an irrigation fluid to flow out of the irrigation hole, and so as to allow transmitting and/or receiving the ultrasonic waves through the irrigation hole. The invention also relates to an imaging system and to a corresponding method for operating a catheter.
