背景:定量磁化率图(QSM)是一种基于对铁和髓鞘含量敏感的磁共振成像的定量测量。这使QSM成为研究和临床实践中用于多发性硬化症(MS)的有希望的非侵入性工具。
目的:我们对QSM在MS中的应用进行了系统评价和荟萃分析。
方法:我们的评论是在PROSPERO(CRD42022309563)上前瞻性注册的。我们在5个数据库中搜索了从开始到2023年4月30日发表的研究。我们确定了83项英国同行评审的研究,这些研究将QSM图像应用于MS队列。纳入的55项研究至少具有以下结果指标之一:MS中的深层灰质QSM值,与健康对照(HC)(k=13)相比或与扩展残疾状态量表(EDSS)的得分相关(k=7),QSM病变特征(k=22)及其临床相关性(k=17),纵向相关(k=11),组织学相关性(k=7),或与其他成像技术相关(k=12)。对深层灰质(DGM)敏感性数据进行了两项荟萃分析,而其余的研究结果只能进行描述性分析。
结果:去除异常值之后,荟萃分析表明,与HC相比,MS的基底神经节易感性(QSM值)显着增加,尾状(k=9,标准化平均差(SDM)=0.54,95%CI=0.39-0.70,I2=46%),壳核(k=9,SDM=0.38,95%CI=0.19-0.57,I2=59%),苍白球(k=9,SDM=0.48,95%CI=0.28-0.67,I2=60%),而丘脑QSM值显着降低(k=12,SDM=-0.39,95%CI=-0.66-0.12,I2=84%);MS的这些易感性差异与年龄无关。Further,壳核QSM值与EDSS呈正相关(k=4,r=0.36,95%CI=0.16~0.53,I2=0%)。关于边缘病变,七项研究中有四项,占所有患者的73%,据报道,边缘病变与更严重的残疾有关。此外,从初始检测到非活动阶段的病变发展与增加平行,趋于稳定(大约两年后),并逐渐降低QSM值,分别。只有一项纵向研究提供了临床结果指标,没有发现相关性。组织学数据表明,铁含量是DGM和边缘病变边缘QSM值的主要来源;此外,当还考虑髓鞘水成像的数据时,髓鞘的减少可能驱动WM病变内QSM值的增加。
结论:与HC相比,我们可以为MS的DGM易感性变化提供荟萃分析证据;基底神经节易感性增加,在壳核中,与残疾有关,而丘脑敏感性降低。除了这些发现,需要进一步的研究来确定QSM在MS研究甚至临床常规中的作用。
BACKGROUND: Quantitative susceptibility mapping (QSM) is a quantitative measure based on magnetic resonance imaging sensitive to iron and myelin content. This makes QSM a promising non-invasive tool for multiple sclerosis (MS) in research and clinical practice.
OBJECTIVE: We performed a systematic
review and meta-analysis on the use of QSM in MS.
METHODS: Our
review was prospectively registered on PROSPERO (CRD42022309563). We searched five databases for studies published between inception and 30th April 2023. We identified 83 English peer-reviewed studies that applied QSM images on MS cohorts. Fifty-five included studies had at least one of the following outcome measures: deep grey matter QSM values in MS, either compared to healthy controls (HC) (k = 13) or correlated with the score on the Expanded Disability Status Scale (EDSS) (k = 7), QSM lesion characteristics (k = 22) and their clinical correlates (k = 17), longitudinal correlates (k = 11), histological correlates (k = 7), or correlates with other imaging techniques (k = 12). Two meta-analyses on deep grey matter (DGM) susceptibility data were performed, while the remaining findings could only be analyzed descriptively.
RESULTS: After outlier removal, meta-analyses demonstrated a significant increase in the basal ganglia susceptibility (QSM values) in MS compared to HC, caudate (k = 9, standardized mean difference (SDM) = 0.54, 95 % CI = 0.39-0.70, I2 = 46 %), putamen (k = 9, SDM = 0.38, 95 % CI = 0.19-0.57, I2 = 59 %), and globus pallidus (k = 9, SDM = 0.48, 95 % CI = 0.28-0.67, I2 = 60 %), whereas thalamic QSM values exhibited a significant reduction (k = 12, SDM = -0.39, 95 % CI = -0.66--0.12, I2 = 84 %); these susceptibility differences in MS were independent of age. Further, putamen QSM values positively correlated with EDSS (k = 4, r = 0.36, 95 % CI = 0.16-0.53, I2 = 0 %). Regarding rim lesions, four out of seven studies, representing 73 % of all patients, reported rim lesions to be associated with more severe disability. Moreover, lesion development from initial detection to the inactive stage is paralleled by increasing, plateauing (after about two years), and gradually decreasing QSM values, respectively. Only one longitudinal study provided clinical outcome measures and found no association. Histological data suggest iron content to be the primary source of QSM values in DGM and at the edges of rim lesions; further, when also considering data from myelin water imaging, the decrease of myelin is likely to drive the increase of QSM values within WM lesions.
CONCLUSIONS: We could provide meta-analytic evidence for DGM susceptibility changes in MS compared to HC; basal ganglia susceptibility is increased and, in the putamen, associated with disability, while thalamic susceptibility is decreased. Beyond these findings, further investigations are necessary to establish the role of QSM in MS for research or even clinical routine.