Comments and illustrations of the WFUMB CEUS liver guidelines: Rare focal liver lesions - non-infectious, non-neoplastic.

In this series of papers on comments and illustrations of the World Federation for Medicine and Biology (WFUMB) guidelines on contrast enhanced ultrasound (CEUS) the topics of non-infectious and non-neoplastic focal liver lesions (FLL) are discussed. Improved detection and characterization of common FLL are the main topics of these guidelines but detailed and illustrating information is missing. The focus in this paper is on non-infectious and non-neoplastic FLL and their appearance on B-mode, Doppler ultrasound and CEUS features. Knowledge of these data should help to raise awareness of these rarer findings, to think of these clinical pictures in the corresponding clinical situation, to interpret the ultrasound images correctly and thus to initiate the appropriate diagnostic and therapeutic steps in time.