相关实验视频
Updated: Sep 19, 2025

09:30
Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
Published on: December 18, 2016
19.7K
基于加速质子共振频率的磁共振温度计,采用优化深度学习方法
Sijie Xu1, Shenyan Zong2, Chang-Sheng Mei3,4
1Biomedical Instrument Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
Medical physics
|May 31, 2025
概括
这项研究增强了利用深度学习进行聚焦超声波 (FUS) 治疗的磁共振 (MR) 温度计. 改进的方法提供了更快,更准确的温度映射,这对于在FUS治疗期间实时监测至关重要.
科学领域:
- 医疗成像医学成像
- 人工智能在医学中的应用
- 治疗性的超声波.
背景情况:
- 基于质子共振频率 (PRF) 的磁共振 (MR) 温度计对于聚焦超声波 (FUS) 热除疗法至关重要.
- 准确和快速的温度反对于确保临床FUS治疗的安全性和有效性至关重要.
研究的目的:
- 使用先进的深度学习方法,在动态MR温度图重建中增强时间分辨率.
- 为了支持有效的FUS治疗的实时监控能力.
主要方法:
- 应用了五种神经网络架构 (级联网,复杂值U-Net,转移窗口变压器,实值U-Net,ResUNet) 来从低采样k空间数据中重建温度图.
- 集成的训练优化:数据增强,知识蒸,以及一个新的振幅相解损失函数.
- 使用幻影,ex vivo组织和临床子宫纤维瘤数据集验证了这一方法.
主要成果:
- 在2×和4×低样本分别获得了1.9和3.7的加速度因子.
- 经过优化后的ResUNet在温度地图重建时,表现出高性能,根平均平方误差 (RMSE) 较低 (例如,在2倍加速时的幻影数据的0.89°C).
- 高子系数 (例如,在2倍加速时为43°C的同热区域0.81) 和有利的布兰德-阿尔特曼分析证实了准确性.
结论:
- 基于深度学习的重建显著提高了FUS治疗的MR温度计准确性和效率.
- 该方法显示了临床适用性,特别是对于子宫纤维瘤治疗.
- 潜在的扩展到其他MRI引导的FUS应用程序,如基本震和前列腺癌治疗.
相关概念视频
Double Resonance Techniques: Overview
310
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...
310
NMR 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
Magnetic Resonance Imaging
7.3K
Magnetic resonance imaging (MRI) is a noninvasive medical imaging technique based on a phenomenon of nuclear physics discovered in the 1930s, in which matter exposed to magnetic fields and radio waves was found to emit radio signals. In 1970, a physician and researcher named Raymond Damadian noticed that malignant (cancerous) tissue gave off different signals than normal body tissue. He applied for a patent for the first MRI scanning device in clinical use by the early 1980s. The early MRI...
7.3K
NMR Spectrometers: Radiofrequency Pulses and Pulse Sequences
935
A pulse is a short burst of radio waves distributed over a range of frequencies that simultaneously excites all the nuclei in the sample. Upon passing a radio frequency pulse along the x-axis, the nuclei absorb energy corresponding to their Larmor frequencies and achieve resonance. This shifts the net magnetization vector from the z-axis toward the transverse plane. This angle of rotation of the magnetization vector, or the flip angle, is proportional to the duration and intensity of the pulse.
935

