Mangia Silvia, Carpenter Adam F, Tyan Andy E, Eberly Lynn E, Garwood Michael, Michaeli Shalom
Center for Magnetic Resonance Research (CMRR), Department of Radiology, University of Minnesota, USA
Department of Neurology, University of Minnesota, USA Brain Sciences Center, VA Medical Center, USA.
Mult Scler. 2014 Jul;20(8):1066-73. doi: 10.1177/1352458513515084. Epub 2013 Dec 12.
Diffuse abnormalities are known to occur within the brain tissue of multiple sclerosis (MS) patients that is "normal appearing" on T1-weighted and T2-weighted magnetic resonance images.
With the goal of exploring the sensitivity of novel MRI parameters to detect such abnormalities, we implemented an inversion-prepared magnetization transfer (MT) protocol and adiabatic T1ρ and T2ρ rotating frame relaxation methods.
Nine relapsing-remitting MS patients and seven healthy controls were recruited. Relaxation parameters were measured in a single slice just above the lateral ventricles and approximately parallel to the AC-PC line.
The MT ratio of regions encompassing the normal-appearing white matter (NAWM) was different in MS patients as compared with controls (p = 0.043); however, the T1 measured during off-resonance irradiation (T1sat) was substantially more sensitive than the MT ratio for detecting differences between groups (p = 0.0006). Adiabatic T1ρ was significantly prolonged in the NAWM of MS patents as compared to controls (by 6%, p = 0.026), while no differences were found among groups for T2ρ. No differences among groups were observed in the cortical gray matter for any relaxation parameter.
The results suggest degenerative processes occurring in the NAWM of MS, likely not accompanied by significant abnormalities in iron content.
已知在多发性硬化症（MS）患者的脑组织中会出现弥漫性异常，这些异常在T1加权和T2加权磁共振图像上表现为“正常”。
为了探索新型MRI参数检测此类异常的敏感性，我们实施了反转准备的磁化传递（MT）方案以及绝热T1ρ和T2ρ旋转框架弛豫方法。
招募了9名复发缓解型MS患者和7名健康对照者。在侧脑室上方且大致平行于AC-PC线的单个层面测量弛豫参数。
与对照组相比，MS患者中包含正常外观白质（NAWM）区域的MT比率有所不同（p = 0.043）；然而，在失谐照射期间测量的T1（T1sat）在检测组间差异方面比MT比率更敏感（p = 0.0006）。与对照组相比，MS患者NAWM中的绝热T1ρ显著延长（延长6%，p = 0.026），而T2ρ在组间未发现差异。在任何弛豫参数方面，皮质灰质在组间均未观察到差异。
结果表明MS的NAWM中存在退行性过程，可能未伴有铁含量的显著异常。
