The study on biological focal region of high intensity focused ultrasound under ultrasonography monitoring

Objective To explore accuracy and reliability of ultrasonography monitoring used for high intensity focused ultrasound(HIFU) therapy.Methods Calf liver tissues were exposed to HIFU with different intensity and duration series. The ultrasonography prior to and posterior to exposure were inspected, the gray values were measured,and the area of ultrasound imaging (S USI ) and biological focal region (S BFR ) were compared.Results A bright hyperechoic spot was resulted and gray values were increased at the focal region after exposure. S USI was almost equal to S BFR after one minute duration(t= 0.308 ,P 0.05 ).Conclusions The gray value could be used to determine the therapeutic dosage and the effectiveness.