动态聚焦回波超声诊断图像空间分辨力特性的实验研究  

Experimental Study on Spatial Resolution of Ultrasonic Diagnostic Image Using Dynamic Focused Echo

作　　者：邢晋放[1] 曹铁生[1] 段云友[1] 

机构地区：[1]解放军第四军医大学唐都医院超声诊断科,西安市710038

出　　处：《中国超声医学杂志》2004年第8期561-564,共4页Chinese Journal of Ultrasound in Medicine

基　　金：中国博士后科学基金二等资助项目 (No.2 0 0 30 340 55)

摘　　要：目的　分析利用时间延迟动态聚焦方式进行回波成像时 ,超声诊断图像的空间分辨力特性。方法　将两根非吸收缝线平行固定于刻度直尺框架上 ,制成实验模型。超声诊断设备选用具有全数字化显像系统的超声医学成像仪 ,超声换能器选用相控阵探头 (7V3C) ,频率为 7MHz。在保持缝线与探头距离不变的情况下 ,改变发射声束聚焦的焦点位置 ,同时观察图像分辨力变化。结果　当发射声束聚焦的焦点位置 (即焦距 )发生改变时 ,超声诊断图像的侧向分辨力没有产生变化。结论　采用时间延迟动态聚焦方式进行回波超声诊断成像 ,能够克服超声波束宽度的影响 ,对介质中各个空间位置的目标物(回波源 )精确地定位显像。Objective To analyse spatial resolution of ultrasonic diagnostic image using dynamic focused mode with time delay of echo signal.Methods The experimental model,in which two pieces of non-absorbable suture were fixed parallelly on shelves of graduated rule,was made.The ultrasonic imaging instrument was equipped with display system of complete digitized figure.The transducer elected was phased array,with frequency of 7 MHz.On the condition that the distance between suture and transducer was kept invariability,the focus position of ultrasonic wave emitted should be changed,at the same time,the changes of image resolution would be observed.Results When the focus position of ultrasonic wave emitted was changed,the lateral image resolution would not be changed.Conclusions This method can overcome the influence of ultrasonic beam width and can exactly and accurately differentiate positions of the targets(the sources of the echo)located at various spatial postion in medium by dynamic focused echo mode with time delay.

关 键 词：动态聚焦回波 超声诊断图像 空间分辨力 电子聚焦 超声成像 

分 类 号：R445.1[医药卫生—影像医学与核医学]