Objective:To observe the destructive characteristics of the bovine liver induced by focused ultrasound clamp technique.Methods:A focused ultrasound surgical clamp(FUSC) consisted of two transducers fixed on a forceps-like handle.The directions of focused ultrasound beams were opposite

with the same central axes.The thickness of bovine liver in vitro ranged from 4 to 10cm.Ultrasound energy was continuously delivered to ablate the liver with a frequency of 1.6MHz

and spatial peak pulse average acoustic intensity(ISPPA) of 12 000W/cm2.The characteristics of complete coagulation necrosis and exposure time were measured after FUSC exposure

and pathological changes in treated bovine liver tissue were observed.Results:FUSC induced complete coagulation necrosis of predetermined bovine liver targets.The shape of coagulation necrosis was corresponded with focused ultrasound beam

with 2.72～3.20cm in length and 1.44～1.80cm in width.However

under the same exposure energy

exposure time for complete necrosis increased

as the thickness of the liver increased.Conclusion:FUSC can induce complete coagulation necrosis of predetermined bovine liver targets.This study would provide a novel surgical instrument for hepatectomy.