Xu Chen, Yuan Baohong, Zhu Quing
University of Connecticut, Department of Electrical and Computer Engineering, Storrs, Connecticut 06269, USA.
J Biomed Opt. 2008 Jul-Aug;13(4):044002. doi: 10.1117/1.2966703.
Shallow lesions less than 1.5-cm deep are frequently seen in breast patients when they are scanned in reflection geometry. Two boundary conditions are compared for imaging shallow lesions, and a new probe design is introduced. A partial reflection boundary condition is suitable for imaging shallow lesions less than 1.0-cm deep; whereas an absorption boundary condition is desirable for imaging lesions more than 1.5-cm deep. Our new probe design incorporates either a partial reflection boundary or an absorption boundary based on a priori knowledge of lesion depth provided by coregistered real-time ultrasound images. An angled source is introduced to further improve the illumination of the region between 1.0- to 1.5-cm depths. Simulation, phantom, and freshly excised mouse tumor experiments demonstrate that targets located at different depths can be uniformly reconstructed. A clinical example is given to demonstrate the utility of this new approach for optimally probing lesions located at different depths.
当以反射几何结构对乳腺患者进行扫描时，经常会发现深度小于1.5厘米的浅表病变。比较了两种用于浅表病变成像的边界条件，并引入了一种新的探头设计。部分反射边界条件适用于深度小于1.0厘米的浅表病变成像；而吸收边界条件则适用于深度大于1.5厘米的病变成像。我们的新探头设计根据配准的实时超声图像提供的病变深度先验知识，纳入了部分反射边界或吸收边界。引入了一个倾斜源，以进一步改善1.0至1.5厘米深度区域的照明。模拟、体模和新鲜切除的小鼠肿瘤实验表明，位于不同深度的目标可以被均匀重建。给出了一个临床实例，以证明这种新方法在最佳探测不同深度病变方面的实用性。
