Straub Sina, El-Sanosy Edris, Emmerich Julian, Sandig Frederik L, Ladd Mark E, Schlemmer Heinz-Peter
Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
Faculty of Medicine, Heidelberg University, Heidelberg, Germany.
NMR Biomed. 2023 Mar;36(3):e4847. doi: 10.1002/nbm.4847. Epub 2022 Nov 14.
Substantial cortical gray matter tissue damage, which correlates with clinical disease severity, has been revealed in multiple sclerosis (MS) using advanced magnetic resonance imaging (MRI) methods at 3 T and the use of ultra-high field, as well as in histopathology studies. While clinical assessment mainly focuses on lesions using - and -weighted MRI, quantitative MRI (qMRI) methods are capable of uncovering subtle microstructural changes. The aim of this ultra-high field study is to extract possible future MR biomarkers for the quantitative evaluation of regional cortical pathology. Because of their sensitivity to iron, myelin, and in part specifically to cortical demyelination, , , , and susceptibility mapping were performed including two novel susceptibility markers; in addition, cortical thickness as well as the volumes of 34 cortical regions were computed. Data were acquired in 20 patients and 16 age- and sex-matched healthy controls. In 18 cortical regions, large to very large effect sizes (Cohen's d ≥ 1) and statistically significant differences in qMRI values between patients and controls were revealed compared with only four regions when using more standard MR measures, namely, volume and cortical thickness. Moreover, a decrease in all susceptibility contrasts ( , , and values indicates that the role of cortical demyelination might outweigh inflammatory processes in the form of iron accumulation in cortical MS pathology, and might also indicate iron loss. A significant association between susceptibility contrasts as well as of the caudal middle frontal gyrus and disease duration was found (adjusted R : 0.602, p = 0.0011). Quantitative MRI parameters might be more sensitive towards regional cortical pathology compared with the use of conventional markers only and therefore may play a role in early detection of tissue damage in MS in the future.
使用3T先进磁共振成像（MRI）方法、超高场以及组织病理学研究，已揭示出多发性硬化症（MS）存在大量与临床疾病严重程度相关的皮质灰质组织损伤。虽然临床评估主要通过T1加权和T2加权MRI关注病变，但定量MRI（qMRI）方法能够发现细微的微观结构变化。这项超高场研究的目的是提取未来可能用于定量评估局部皮质病变的磁共振生物标志物。由于其对铁、髓磷脂的敏感性，部分还对皮质脱髓鞘具有特异性，因此进行了相位成像、定量磁敏感成像、T2加权成像和磁敏感图谱分析，包括两种新型磁敏感标志物；此外，还计算了皮质厚度以及34个皮质区域的体积。对20例患者和16名年龄及性别匹配的健康对照者进行了数据采集。与仅使用更标准的磁共振测量方法（即体积和皮质厚度）时只有四个区域显示差异相比，在18个皮质区域发现患者与对照者之间qMRI值存在大到非常大的效应量（科恩d值≥1）且具有统计学显著差异。此外，所有磁敏感对比度（相位成像、定量磁敏感成像、T2加权成像和磁敏感图谱值）均降低，这表明在皮质MS病变中，皮质脱髓鞘的作用可能超过铁积累形式的炎症过程，也可能表明铁丢失。发现尾侧额中回的磁敏感对比度以及T2*加权成像与疾病持续时间之间存在显著关联（调整后的R²：0.602，p = 0.0011）。与仅使用传统标志物相比，定量MRI参数可能对局部皮质病变更敏感，因此未来可能在MS组织损伤的早期检测中发挥作用。
