This paper studies the problem of the temporal features extracted from contrast-enhanced ultrasound video frames in order to find discriminative parameters which will be used later, in conjunction with other feature types, in the development of a computer-aided diagnosis system for focal liver lesions. The created tool will enable safe, cheap, early and largely accessible detection of many hepatic diseases. Our work improves on and broadens previous work in the field in several aspects, e.g. a novel robust fitting procedure and the definition and selection procedure for temporal descriptors.