McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada.
Magn Reson Med. 2010 Mar;63(3):633-40. doi: 10.1002/mrm.22244.
Quantitative magnetization transfer imaging provides in vivo estimates of liquid and semisolid constituents of tissue, while estimates of the liquid subpopulations, including myelin water, can be obtained from multicomponent T(2) analysis. Both methods have been suggested to provide improved myelin specificity compared to conventional MRI. The goal of this study was to investigate the sensitivity of each technique to the progression of acute, gadolinium-enhancing regions of multiple sclerosis. Magnetization transfer and T(2) relaxometry data were acquired longitudinally over the course of 1 year in five relapsing-remitting multiple sclerosis patients and in five healthy controls. Parametric maps were analyzed in enhancing lesions and normal-appearing white matter regions. Quantitative magnetization transfer parameters in lesions were most abnormal at the time of enhancement and followed a pattern of recovery over subsequent months. Lesion myelin water fraction was abnormal but did not show a significant trend over time. Quantitative magnetization transfer was able to track the degree and timing of the partial recovery in enhancing multiple sclerosis lesions in a small group of patients, while the recovery was not detected in myelin water estimates, possibly due to their large variability. Our data suggest the recovery is characterized by quick resolution of inflammation and a slower remyelination process.
定量磁化转移成像是一种能够提供组织液性和半固态成分的活体估计方法，而对包括髓磷脂水在内的液性亚群的估计则可以通过多成分 T2 分析获得。这两种方法都被认为比传统 MRI 具有更高的髓鞘特异性。本研究的目的是研究每种技术对急性、钆增强多发性硬化症的进展的敏感性。在 5 例复发缓解型多发性硬化症患者和 5 例健康对照者中，在 1 年的时间内进行了纵向磁化转移和 T2 弛豫测量数据采集。在增强病变和正常表现的白质区域中分析了参数图。病变中的定量磁化转移参数在增强时最异常，并在随后的几个月中呈现出恢复的模式。病灶髓磷脂水分数异常，但随时间无明显变化趋势。定量磁化转移能够在一小部分患者的增强多发性硬化症病变中跟踪其部分恢复的程度和时间，而髓磷脂水估计则未检测到恢复，这可能是由于其变异性较大。我们的数据表明，恢复的特点是炎症迅速消退和脱髓鞘过程较慢。
