灰度相关函数应用于HIFU监控的离体研究  

Correlation Coefficient Analysis over Ultrasonography Monitoring of High Intensity Focused Ultrasound on Tissue Ablation in Vitro

作　　者：冯玉洁[1] 李雁[1] 王华[1] 邹建中[1] 钟珊珊[1] 王琦[1] 欧阳挺[1] 

机构地区：[1]重庆医科大学生物医学工程系超声医学工程重庆市市级重点实验室,重庆市400016

出　　处：《中国超声医学杂志》2010年第6期485-488,共4页Chinese Journal of Ultrasound in Medicine

基　　金：国家自然科学基金面上项目(No.30970767)

摘　　要：目的 探讨在高强度聚焦超声（HIFU）辐照过程中,超声图像与HIFU辐照产生凝固性坏死的关系,以提高监控超声对HIFU凝固性坏死的判断灵敏度.方法 在相同声强、辐照时间、辐照深度情况下,HIFU定点辐照离体牛肝,观测靶区辐照前及辐照结束后即刻、1、2、3、4、5 min的声像图变化和灰度值变化,并进行靶区声像图相关函数运算,用支撑矢量机（support vector machine,SVM）筛选参数并得到决策超平面.结果超声图像相关系数可以评价HIFU凝固性坏死情况,其灵敏度高于用灰度评价（χ^2=18.716,P〈0.05）.结论 声像图相关系数判断HIFU辐照的靶组织有无凝固性坏死优于灰度评价.Objective To improve the determination sensitivity of coagulation necrosis caused by high intensity focused ultrasound （HIFU） exposure. Methods The bovine liver in vitro was dot-exposed with HIFU with constant setting of intensity, duration series and depth. The ultrasonographys generated at seven time points were inspected, i. e. prior to the exposure, instantaneous after the exposure and 1-5 minutes after the exposure. The gray values of the graphs were measured, and the correlation of the target area was computed. Based on Support Vector Machine, our method automatically selects the parameters for the determination function. Results The correlation coefficients between ultrasound-image （before and after the exposure） can be used to predict HIFU coagulation necrosis, and its sensitivity was higher than the gray-scale method （χ^2= 18. 716, P〈0.05） . Conclusions Correlation analysis over ultrasonographic data can be used to predict coagulation necrosis of target tissues exposed with HIFU. which is better than traditional gray-scale evaluation method according to this experiment.

关 键 词：高强度聚焦超声 相关函数 支撑矢量机 

分 类 号：R454.3[医药卫生—治疗学]