高强度聚焦超声损伤兔肝脏的剂量及二维超声实时监控

Dosage and real time monitoring using two-dimensional ultrasound in extracorporeal damaging rabbit liver with high intensity focused ultrasound

目的探索高强度聚焦超声损伤兔肝脏的剂量和二维超声实时监控的可行性。方法HIFU发射功率、工作频率、辐照深度恒定,以HIFU定点损伤40例兔肝脏,二维超声实时观察损伤靶区的回声及其随时间的变化,测量回声变化的范围,解剖测量损伤靶区凝固性坏死区的大小,留取凝固性坏死组织标本行病理学检查。结果HIFU体外辐照兔肝脏可在靶区形成凝固性坏死,能效因子为9.22±1.57J/mm3,靶区的回声增强,凝固性坏死体积、最大剖面面积与二维超声测量的回声增强区体积、面积呈线性关系。结论HIFU损伤组织的剂量需大量的实验研究,二维超声可实时监控凝固性坏死的出现,并可预测凝固性坏死体积大小。

Objective:To investigate the dosage in damaging rabbit liver with high intensity focused ultrasound (HIFU) and the feasibility of real time monitoring with two-dimensional ultrasound.Methods:With fixed HIFU emission power,working frequency,radiation depth,40 rabbit livers were damaged extracorporeally with a HIFU mode of intermittent fixed-spot irradiation.Echo of target region was measured and its changes with time were observed,the extent of echo enhancing region were also measured.Coagulative necrosis in rabbit livers were measured after dissection and pathological inspection were made.Results:Irradiation of extracorporeal HIFU made a coagulative necrosis region in rabbit liver,energy efficiency factor (EEF) were 9.22±1.57 J/mm 3,elevating echo of target region were observed,necrotic volume and maximum scar of rabbit livers were related linearly with volume and maximum area of elevating echo region measured by two-dimensional ultrasound.Conclusion:For specific tissue,there are a great deal experiments to do to decide a common HIFU dosage,two-dimensional ultrasound can realize real time monitoring of target region necrosis,echoic change in target region can predict coagulative necrotic volume.