Three-dimensional microwave breast imaging: dispersive dielectric properties estimation using patient-specific basis functions.
Three-dimensional microwave breast imaging: dispersive dielectric properties estimation using patient-specific basis functions.
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DOI：
10.1109/tmi.2008.2008959
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发表时间：
2009-07
影响因子：
10.6
通讯作者：
Hagness SC
中科院分区：
文献类型：
--
作者：
Winters DW;Shea JD;Kosmas P;Van Veen BD;Hagness SC
通过微波断层扫描的乳房成像涉及在离散网格上估计患者乳房内的介电特性的分布。对于三维成像，离散网格中的未知数的数量可能非常大，这导致计算挑战。我们提出了一种新的方法，其中离散网格被替换为相对较少的光滑基函数。通过估计基函数的系数，而不是在离散网格中的每个元素的介电特性，降低了层析成像问题的维数。使用乳房表面的位置的知识来构造基函数。基中使用的函数的数量可以变化以平衡分辨率和计算复杂度。降维的反问题，使应用程序的计算效率，多频逆散射算法在3-D。所提出的方法的有效性进行了验证，使用两个3-D解剖逼真的数字乳房幻影。它示出的情况下，单频微波层析成像的成像精度是当使用原始离散网格时获得的，尽管逆问题的维数的减少。结果也显示了多频算法，它是计算上的挑战，使用原来的离散网格。
Breast imaging via microwave tomography involves estimating the distribution of dielectric properties within the patient's breast on a discrete mesh. The number of unknowns in the discrete mesh can be very large for three-dimensional imaging, and this results in computational challenges. We propose a new approach where the discrete mesh is replaced with a relatively small number of smooth basis functions. The dimension of the tomography problem is reduced by estimating the coefficients of the basis functions instead of the dielectric properties at each element in the discrete mesh. The basis functions are constructed using knowledge of the location of the breast surface. The number of functions used in the basis can be varied to balance resolution and computational complexity. The reduced dimension of the inverse problem enables application of a computationally efficient, multiple-frequency inverse scattering algorithm in 3-D. The efficacy of the proposed approach is verified using two 3-D anatomically realistic numerical breast phantoms. It is shown for the case of single-frequency microwave tomography that the imaging accuracy is comparable to that obtained when the original discrete mesh is used, despite the reduction of the dimension of the inverse problem. Results are also shown for a multiple-frequency algorithm where it is computationally challenging to use the original discrete mesh.