Boss Michael A, Mates John A B, Busch Sarah E, SanGiorgio Paul, Russek Stephen E, Buckenmaier Kai, Irwin Kent D, Cho Hsiao-Mei, Hilton Gene C, Clarke John
Electromagnetics Division, National Institute of Standards and Technology, Boulder, Colorado, USA.
Magn Reson Med. 2014 Dec;72(6):1793-800. doi: 10.1002/mrm.25060. Epub 2013 Nov 26.
Prototype phantoms were designed, constructed, and characterized for the purpose of calibrating ultralow field magnetic resonance imaging (ULF MRI) systems. The phantoms were designed to measure spatial resolution and to quantify sensitivity to systematic variation of proton density and relaxation time, T1 .
The phantoms were characterized first with conventional magnetic resonance scanners at 1.5 and 3 T, and subsequently with a prototype ULF MRI scanner between 107 and 128 μT .
The ULF system demonstrated a 2-mm spatial resolution and, using T1 measurements, distinguished aqueous solutions of MnCl2 differing by 20 μM [Mn(2+) ].
The prototype phantoms proved well-matched to ULF MRI applications, and allowed direct comparison of the performance of ULF and clinical systems.
设计、构建并表征原型体模，用于校准超低场磁共振成像（ULF MRI）系统。这些体模旨在测量空间分辨率，并量化对质子密度和弛豫时间T1的系统变化的敏感度。
首先使用1.5 T和3 T的传统磁共振扫描仪对体模进行表征，随后使用一台107至128 μT的原型ULF MRI扫描仪进行表征。
该ULF系统展现出2毫米的空间分辨率，并且通过T1测量，能够区分浓度相差20 μM [Mn(2+)]的MnCl2水溶液。
事实证明，这些原型体模非常适合ULF MRI应用，并且能够直接比较ULF系统与临床系统的性能。
