Sled J G, Pike G B
McConnell Brain Imaging Centre, Montréal Neurological Institute, McGill University, Montréal, Québec, Canada.
Magn Reson Med. 2000 Apr;43(4):589-93. doi: 10.1002/(sici)1522-2594(200004)43:4<589::aid-mrm14>3.0.co;2-2.
A new method is described for compensating for the bias introduced by variations in radiofrequency (RF) field strength and main magnetic field strength when making quantitative T(2) measurements using MRI. Field measurements made during the MRI study are used in combination with a signal model for off-resonance and imperfect RF pulses to correct the estimated T(2) value at every voxel. Applicable to both multicomponent and conventional single-component T(2) studies, the method has been validated experimentally using paramagnetic salt solutions in a multicompartment phantom. Studies of the human head are used to demonstrate the method in practice.
本文描述了一种新方法,用于在使用磁共振成像(MRI)进行定量T(2)测量时,补偿由射频(RF)场强和主磁场强度变化所引入的偏差。MRI研究期间进行的场测量与用于失谐和不完美RF脉冲的信号模型相结合,以校正每个体素处估计的T(2)值。该方法适用于多组分和传统的单组分T(2)研究,已在多隔室模型中使用顺磁盐溶液进行了实验验证。对人体头部的研究用于在实际中演示该方法。