福里埃增强高阶总变量 (FeHOT) 代网络用于内部断层扫描
Genwei Ma1, Xing Zhao2, Yining Zhu2
1The Academy for Multidisciplinary Studies, Captial Normal University, Beijing, People's Republic of China.
Physics in medicine and biology
|April 3, 2025
概括
本研究介绍了富里埃增强的HOT (FeHOT) 网络,用于从截断的投影数据中高精度的内部计算机断层扫描 (CT) 重建. FeHOT显著提高了图像质量和细节保存,为医学成像提供了更快,更准确的解决方案.
科学领域:
- 医疗成像医学成像
- 计算成像技术的成像
- 图像重建 图像的重建
背景情况:
- 传统的计算机断层扫描 (CT) 方法,如过后投影 (FBP),在低对比度和细节损失方面扎.
- 对于CT重建的深度学习方法经常面临数据一致性的挑战,并且可能过度平滑图像.
- 从截断的投影数据进行内部断层扫描重建仍然是一个重大挑战,影响图像质量和诊断准确性.
研究的目的:
- 开发一种高精度的内部断层扫描重建方法,使用高阶总变量 (HOT) 正规化和基于富里埃的频率域增强.
- 克服现有方法的局限性,包括缓慢的融合,过度光滑和高频细节的丢失.
- 从截断的投影数据中实现准确的重建,增强对比度和边缘保护.
主要方法:
- 提出了一个福里埃增强的HOT (FeHOT) 网络,使用粗到细的策略.
- 采用基于HOT的未滚动代网络,并使用已学习的初级-双元算法来实现数据一致性和高阶梯度约束.
- 集成了一个富里埃增强的U-Net模块来选择性地处理频率组件,保留过后投影 (FBP) 结果的边缘和纹理细节.
主要成果:
- 在AAPM和临床医疗数据集上,FeHOT表现优于FBP,HOT,AG-Net和PD-Net.
- 实现了高峰信号噪声比 (PSNR) 值 (例如,医疗数据上41.17无噪声,39.24噪声),显著优于现有方法.
- 在边缘保护方面显示出显著的改进 (例如,SSIM从0.9877增加到0.9976) 和在五次代内进行高质量的重建.
结论:
- 通过将经典的HOT理论与深度学习相结合,FeHOT代表了室内断层扫描的重大进步.
- 引入频域运算有效地解决了CT图像中零碎常数假设的局限性.
- FeHOT为高质量的内部断层扫描重建提供了计算效率高,准确的解决方案,适合低剂量成像应用.
相关概念视频
01:11Continuous -time Fourier Transform
249
The Fourier series is instrumental in representing periodic functions, offering a powerful method to decompose such functions into a sum of sinusoids. This technique, however, necessitates modification when applied to nonperiodic functions. Consider a pulse-train waveform consisting of a series of rectangular pulses. When these pulses have a finite period, they can be accurately represented by a Fourier series. Yet, as the period approaches infinity, resulting in a single, isolated pulse, the...
249
01:10Fast Fourier Transform
229
The Fast Fourier Transform (FFT) is a computational algorithm designed to compute the Discrete Fourier Transform (DFT) efficiently. By breaking down the calculations into smaller, manageable sections, the FFT significantly reduces the computational complexity involved. Direct computation of an N-point DFT requires N2 complex multiplications, whereas the FFT algorithm needs only (N/2)log2N multiplications, offering a much faster performance.
The computational efficiency of the FFT becomes...
The computational efficiency of the FFT becomes...
229
01:26Linear Approximation in Frequency Domain
80
Linear systems are characterized by two main properties: superposition and homogeneity. Superposition allows the response to multiple inputs to be the sum of the responses to each individual input. Homogeneity ensures that scaling an input by a scalar results in the response being scaled by the same scalar.
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
80
01:15Discrete Fourier Transform
194
The Discrete Fourier Transform (DFT) is a fundamental tool in signal processing, extending the discrete-time Fourier transform by evaluating discrete signals at uniformly spaced frequency intervals. This transformation converts a finite sequence of time-domain samples into frequency components, each representing complex sinusoids ordered by frequency. The DFT translates these sequences into the frequency domain, effectively indicating the magnitude and phase of each frequency component present...
194
01:10Reconstruction of Signal using Interpolation
151
Signal processing techniques are essential for accurately converting continuous signals to digital formats and vice versa. When a continuous signal is sampled with a period T, the resulting sampled signal exhibits replicas of the original spectrum in the frequency domain, spaced at intervals equal to the sampling frequency. To handle this sampled signal, a zero-order hold method can be applied, which creates a piecewise constant signal by retaining each sample's value until the next...
151
01:10Computed Tomography
4.2K
Tomography refers to imaging by sections. Computed tomography (CT) is a non-invasive imaging technique that uses computers to analyze several cross-sectional X-rays to reveal minute details about structures in the body.
The technique was invented in the 1970s and is based on the principle that as X-rays pass through the body, they are absorbed or reflected at different levels. In the technique, a patient lies on a motorized platform while a computerized axial tomography (CAT) scanner rotates...
The technique was invented in the 1970s and is based on the principle that as X-rays pass through the body, they are absorbed or reflected at different levels. In the technique, a patient lies on a motorized platform while a computerized axial tomography (CAT) scanner rotates...
4.2K