在横向变化的介质中进行分布式偏差校正的声速估计
Rehman Ali1, Trevor M Mitcham1, Melanie Singh2
1Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, USA.
概括
这项研究引入了一种代方法来纠正超声成像中的声速变化,显著改善幻影和体内实验中的图像分辨率和损伤对比度.
科学领域:
- 医疗成像医学成像
- 超声波技术 超声波技术 超声波技术
- 计算物理 计算物理
背景情况:
- 空间声音速度的变化导致医学超声波中的图像偏差.
- 以前的校正方法仅限于分层介质,无法解决横向变化.
- 侧向声音速度的变化显著影响图像质量.
研究的目的:
- 开发一种代的声速估计和偏差校正技术.
- 为了建模和纠正由横向变化的介质引起的误差.
- 改进超声波中偏差校正的实际实施.
主要方法:
- 从地质物理学中调整了一个富里埃分步迁移技术.
- 实现了一种代的声音速度估计和分布式偏差校正.
- 通过模拟,幻影和体内实验验证实了该方法.
主要成果:
- 在幻影实验中,点对象分辨率提高了多达4倍.
- 在幻影实验中,损伤对比度提高到10.0dB.
- 在模拟和in-vivo设置中表现出能力.
结论:
- 代技术有效地纠正来自横向变化的声音速度的误差.
- 这种方法提高了图像质量,超出了以前的限制.
- 为医疗超声波成像提供更好的分辨率和对比度.
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