Spatial and temporal aberrator stability for real-time adaptive imaging
Spatial and temporal aberrator stability for real-time adaptive imaging
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DOI：
10.1109/tuffc.2005.1516023
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发表时间：
2005-09-01
影响因子：
3.6
通讯作者：
Trahey, GE
中科院分区：
文献类型：
--
作者：
Dahl, JJ;Soo, MS;Trahey, GE
报道的实时自适应成像系统使用近场相位校正技术，这是期望的，因为它们的简单的实现和它们与当前的系统架构的兼容性。像差稳定性对于自适应成像是重要的，因为它定义了近场相位估计有效的空间和时间限制。空间像差稳定性确定了像差的所需空间采样，而时间像差稳定性确定了可以使用像差分布的时间长度。在本研究中，报告了乳腺、肝脏和甲状腺组织临床测量像差的空间和时间稳定性。像差估计之间的交叉相关性显示，在80%的相关性下，乳腺、肝脏和甲状腺组织的像差分别具有0.44、0.28和0.20 mm的方位等晕斑尺寸。轴向等晕斑尺寸分别为1.26，0.76，和1.80毫米相同的组织，分别为80%的相关性。确定乳腺和甲状腺组织在80%相关性下的时间稳定性大于1.5秒，肝脏为0.65秒。噪声，运动和目标的不均匀性对像差稳定性的影响，其特征在于模拟和组织模仿体模实验。
Reported real-time adaptive imaging systems use near-field phase correction techniques, which are desired because of their simple implementation and their compatibility with current system architectures. Aberrator stability is important to adaptive imaging because it defines the spatial and temporal limits for which the near-field phase estimates are valid. Spatial aberrator stability determines the required spatial sampling of the aberrator, and temporal aberrator stability determines the length of time for which the aberration profile can be used. In this study, the spatial and temporal stability of clinically measured aberrations is reported for breast, liver, and thyroid tissue. Cross correlations between aberration estimates revealed aberrators to have azimuthal isoplanatic patch sizes of 0.44, 0.28, and 0.20 mm for breast, liver, and thyroid tissue, respectively, at 80% correlation. Axial isoplanatic patch sizes were 1.26, 0.76, and 1.80 mm for the same tissue, respectively, at 80% correlation. Temporal stability at 80% correlation was determined to be greater than 1.5 seconds for breast and thyroid tissue, and 0.65 seconds for the liver. The effects of noise, motion, and target nonuniformity on aberrator stability are characterized by simulations and experiments in tissue mimicking phantoms.