Ultrasound diagnosis is the globally predominant single radiological modality in terms of its utilisation rate. Its relative simplicity in use, and its speed, reliability, low cost, and lack of risk, are all factors associated with its increasingly widespread use. The possibility of monitoring processes in real time opens up new approaches to ultrasound-assisted tumour treatment, biopsy, and blood flow and perfusion studies. The development of an ultrasound-specific contrast medium removed the last obstacle to functional ultrasonography and its use in the evaluation of tumour treatment.