Studies on Miniaturized Field Gradient Components in Magnetic Resonance Micro-system

核磁共振微系統中微小化磁場梯度元件之研究

鄭信莉(Hsin-Li Cheng)

指導教授 ： 范龍生 ； 齊正中

國立清華大學/理學院/物理學系/博士(2009年)

https://doi.org/10.6843/NTHU.2009.00466

摘要

Nuclear magnetic resonance (NMR) spectroscopy and MR imaging technique are the most powerful methods available for determining molecular structures and non-invasive 3D imaging. However, the current MRI resolutions are limited by the achievable SNR and sensitivity in a given time duration. We demonstrated that the miniaturization of MR Field components (RF and Gradient coils) and integration of associated elements using the mechanical technology can achieve higher sensitivity and less resolution. Chemical identification achieved with micro-coils in Bruker 1H 11.7-Tesla MR spectroscopy. Analytically solved, simulated, and MEMS fabricated the 6.1 miniaturized gradient components were used for a compact 3-Tesla desk-top magnet. Magnet thermal control system for temperatures stabilized within 0.01℃ is demonstrated. In Bruker 4.7-Tesla superconducting magnet, the finger-print x-, y-, and z- micro gradient components’ design achieved using the target field approach and Maxwell 3D simulation. MEMS fabricated coils measured with a Hall Effect Gauss meter were consistent with the simulation. Thus, significant improvements in MR sensitivity and magnetic field gradient by micro-sized RF and gradient components were generated for high-resolution MR imaging.

關鍵字

核磁共振微系統 ； 微小化磁場梯度元件 ； 磁場元件

參考文獻

[1] Jian-Ming Jin, “Electromagnetics in Magnetic Resonance Imaging”, IEEE

“Triaxial Magnetic Field Gradient System for Microcoil Magnetic Resonance

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