U.S. Department of Commerce, National Institute of Standards and Technology, 325 Broadway, Boulder, CO, 80305, USA.
MAGMA. 2023 Jul;36(3):477-485. doi: 10.1007/s10334-023-01086-y. Epub 2023 May 20.
Temperature controlled T and T relaxation times are measured on NiCl and MnCl solutions from the ISMRM/NIST system phantom at low magnetic field strengths of 6.5 mT, 64 mT and 550 mT.
The T and T were measured of five samples with increasing concentrations of NiCl and five samples with increasing concentrations of MnCl. All samples were scanned at 6.5 mT, 64 mT and 550 mT, at sample temperatures ranging from 10 °C to 37 °C.
The NiCl solutions showed little change in T and T with magnetic field strength, and both relaxation times decreased with increasing temperature. The MnCl solutions showed an increase in T and a decrease in T with increasing magnetic field strength, and both T and T increased with increasing temperature.
The low field relaxation rates of the NiCl and MnCl arrays in the ISMRM/NIST system phantom are investigated and compared to results from clinical field strengths of 1.5 T and 3.0 T. The measurements can be used as a benchmark for MRI system functionality and stability, especially when MRI systems are taken out of the radiology suite or laboratory and into less traditional environments.
在低磁场强度为 6.5 mT、64 mT 和 550 mT 下，对 ISMRM/NIST 系统模型中的 NiCl 和 MnCl 溶液进行温度控制的 T1 和 T2 弛豫时间测量。
测量了 NiCl 浓度递增的五个样品和 MnCl 浓度递增的五个样品的 T1 和 T2。所有样品均在 6.5 mT、64 mT 和 550 mT 下，在 10°C 至 37°C 的样品温度范围内进行扫描。
NiCl 溶液的 T1 和 T2 随磁场强度变化不大，且两种弛豫时间随温度升高而降低。MnCl 溶液的 T1 和 T2 随磁场强度增加而增加，随温度升高而降低。
研究了 ISMRM/NIST 系统模型中 NiCl 和 MnCl 阵列的低场弛豫率，并与临床 1.5T 和 3.0T 场强的结果进行了比较。这些测量结果可作为 MRI 系统功能和稳定性的基准，特别是当 MRI 系统从放射科或实验室带到不太传统的环境中时。
