用压缩传感和低等级的汉克尔矩阵完成方法评估样本不足的31P-MRS数据的重建准确性
Jossian A García1, Michael D Noseworthy2, Alejandro Santos-Díaz1
1Tecnologico de Monterrey, School of Engineering and Sciences, Mexico City, Mexico.
Frontiers in endocrinology
|July 2, 2025
概括
压缩传感通过低采样数据加速磁共振光谱 (P-MRS). 重建的准确性取决于特定的采样模式和噪声,而不仅仅是加速因子.
科学领域:
- 生物物理学的生物物理.
- 医疗成像医学成像
- 代谢学 代谢学 代谢学
背景情况:
- 通过测量组织中的关键代谢物,P-MRS/MRSI可以在体内评估能量代谢.
- P-MRS/MRSI的临床应用受到长时间的数据采集时间的限制.
- 压缩传感 (CS) 是MRI和MRS的新兴加速技术,需要不连贯的下面样本来准确地重建信号.
研究的目的:
- 为了评估低采样模式对P-MRS信号重建质量的影响.
- 调查噪声和采样密度对使用低级汉克尔矩阵完成重建准确性的影响.
主要方法:
- 使用各种伪随机低样本模式对P-MRS数据进行实验性评估.
- 低级汉克尔矩阵完成的应用,用于信号重建.
- 分析重建准确性与低采样因子,噪声水平和采样时间密度相关的分析.
主要成果:
- 重建的准确性受到采样点的特定选择的显著影响,而不仅仅是低采样因素.
- 获取信号中的噪声水平增加导致重建质量更明显的恶化.
- 在早期时间点收集的样本密度更高与改进的重建准确性有正相关.
结论:
- 在31P-MRS.中,选择低样本模式对于成功的压缩传感至关重要.
- 减少噪音的策略和优化采样时间表,专注于早期时间点,对于提高重建准确度至关重要.
- 在某些场景中,可能可以省略以后的时间样本,而不会对某些场景的重建错误产生统计学上显著的影响.
相关概念视频
01:18Aliasing
238
Accurate signal sampling and reconstruction are crucial in various signal-processing applications. A time-domain signal's spectrum can be revealed using its Fourier transform. When this signal is sampled at a specific frequency, it results in multiple scaled replicas of the original spectrum in the frequency domain. The spacing of these replicas is determined by the sampling frequency.
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original...
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original...
238
01:10Reconstruction of Signal using Interpolation
353
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...
353
01:10Computed Tomography
6.3K
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...
6.3K
01:14NMR Spectrometers: Resolution and Error Correction
784
When magnetic nuclei in a sample achieve resonance and undergo relaxation, the signal detected in NMR is an approximately exponential free induction decay. Fourier transform of an exponential decay yields a Lorentzian peak in the frequency domain. Lorentzian peaks in an NMR spectrum are defined by their amplitude, full width at half maximum, and position, where the peak width is governed by the spin-spin relaxation time alone. In real experiments, however, the applied magnetic field is rendered...
784
01:22Upsampling
322
Managing signal sampling rates is essential in digital signal processing to maintain signal integrity. A decimated signal, characterized by a reduced frequency range due to its lower sampling rate, can be upsampled by inserting zeros between each sample. This upsampling process expands the original spectrum and introduces repeated spectral replicas at intervals dictated by the new Nyquist frequency. To refine this zero-inserted sequence, it is passed through a lowpass filter with a cutoff...
322
01:162D NMR: Overview of Homonuclear Correlation Techniques
300
Homonuclear correlation spectroscopy (COSY) is a powerful technique used in Nuclear Magnetic Resonance (NMR) spectroscopy to study the correlations between nuclei of the same type within a molecule. It provides information about scalar couplings between adjacent nuclei, which helps determine connectivity and structural information. There are several COSY variants, each with its unique strengths and experimental parameters.
COSY90 is the standard two-dimensional (2D) COSY experiment that...
COSY90 is the standard two-dimensional (2D) COSY experiment that...
300